JP4086765B2 - Robot equipment - Google Patents

Description

  The present invention relates to a multi-axis drive system mechanical device such as a robot, a general-purpose assembly device, a robot / hand device, and other multi-axis control devices, and in particular, a position control composed of a proportional gain of phase compensation and a phase compensation element. The present invention relates to a robot apparatus in which each joint part is constituted by a servo controller of an actuator constituting the system.

  More particularly, the present invention relates to a bipedal robot apparatus in which each axis link is controlled by high gain PD control, and in particular, characteristics of the actuator itself and actuators during various operations such as robot walking. The present invention relates to a robot apparatus that realizes a stable and highly efficient operation by dynamically or statically controlling the characteristics of the controller.

  In addition, the present invention provides stable and highly efficient operation by dynamically or statically controlling the characteristics of the actuator itself and the characteristics of the servo controller of the actuator during the execution of various operations such as raising and lowering stairs. The present invention relates to a legged mobile robot that realizes the above.

  The present invention also enables stable and highly efficient operation by dynamically or statically controlling the characteristics of the actuator itself and the characteristics of the actuator controller when performing various operations such as turning the aircraft. The present invention relates to a robot apparatus to be realized.

  A mechanical device that uses an electrical or magnetic action to perform a movement resembling human movement is called a “robot”. It is said that the word “robot” comes from the Slavic word “ROBOTA (slave machine)”. In Japan, robots started to spread from the end of the 1960s, but many of them are industrial robots such as manipulators and transfer robots for the purpose of automating and unmanned production operations in factories. Met.

  A stationary type robot such as an arm type robot that is implanted and used in a specific place operates only in a fixed / local work space such as an assembly / sorting operation of parts. In contrast, a mobile robot has a non-restricted working space, and can freely move on a predetermined route or a non-route to perform a predetermined or arbitrary human work, or a human or dog. Alternatively, a wide variety of services can be provided to replace other life forms. In particular, legged mobile robots are more unstable than crawler and tire type robots, making posture control and walking control difficult, but it is difficult to move up and down stairs and ladders, get over obstacles, and distinguish between leveling and rough terrain. It is excellent in that it can realize flexible walking / running operation regardless of the type.

  Recently, the model is based on the body mechanism and movement of a four-legged animal such as a dog or a cat, or a pet-type robot that mimics its movement, or a human-like animal that walks upright on two legs. Research and development related to legged mobile robots such as the “humanoid” or “humanoid” robots have been progressed, and expectations for practical use are also increasing.

  This type of legged mobile robot generally has a large number of joint degrees of freedom, and the movement of the joint is realized by an actuator motor. Further, by extracting the rotation position and rotation amount of each motor and performing servo control, a desired operation pattern is reproduced and posture control is performed.

  In a multi-axis drive system mechanical device, it is necessary to stably detect the rotational position of each axis with high accuracy and operate it accurately according to a position command. In particular, in a biped upright legged mobile robot such as a humanoid robot, the robot autonomously confirms its posture position immediately after turning on the power supply, and sets each axis to a stable posture position. Must be moved. Therefore, in the servo actuator that gives the degree of freedom of rotation of each joint, higher-precision and higher-speed positioning control and higher torque output must be performed with lower power consumption.

  Basically, legged mobile robots have multiple “limbs” composed of rotating joints, but they are closed links to the outside world and work objects such as stable bipedal walking and stable bi-arm work. The switching operation between the state and the open link state is required to be performed at high speed.

  For example, by alternately repeating the single-leg support period and the both-leg support period with the left and right movable legs, it is possible to perform walking, raising and lowering stairs, turning the body, and various other legged operations. Here, when a legged mobile robot transitions from an open link mechanism to a closed link mechanism with a floor surface or a wall surface, as in the case of transition from single leg support to both leg support, for example, In the past, there is often a gap between the predicted value for control and the actually measured value.

  Due to the gap between the prediction and the actual measurement, “peeling” that has not yet reached the floor when the foot is predicted to land, or conversely, it is earlier than the time when the foot is predicted to land. A phenomenon such as "collision" that reaches the floor surface is invited. These separation and collision with the floor surface have a great influence on the posture stability control of the legged mobile robot, such as the aircraft falling.

  Conventionally, the switching operation from the open link state to the closed link state is performed at high speed by feedback control by software using the force sensor information arranged at the tip of the limb or the torque information from the actuator that drives the joint. It has been tried. However, the realization of stable operation by this method is extremely difficult technically because it requires a high-speed feedback cycle, high joint drive resolution, high joint drive speed, and acceleration to the extent that it is impractical.

  Also, in multi-axis robots such as bipedal walking (human type), each joint link is controlled by high gain PD control in each joint part viewed from the motion control theory, and they operate with constant characteristics It is common to do.

  However, as can be seen from the results of human movement research, in order to achieve stable and highly efficient movement, it is necessary to increase or decrease the force locally or increase or decrease the compliance (mechanical passivity) of each joint part. We believe this is important.

  When capturing the movement of each joint axis as a position control system, it is better to use a servo controller with high gain and high bandwidth to control the control deviation to be small. Considering the effects of energy and kinetic energy, it is preferable to simultaneously reduce the gain or raise or lower the frequency band for which phase compensation is performed.

  However, in order to realize such control on the robot body, it is necessary to have a function to dynamically and statically control the characteristics of the actuator itself and the characteristics of the actuator controller.

  For example, proposals have been made regarding walking control devices for legged mobile robots that can stably walk on known or unknown walking surfaces. In other words, when the bipedal legged mobile robot has a human body-like structure with arms on the upper body, when the frictional force decreases on the walking road surface and the stability decreases, the state is driven and stabilized. Can be secured or recovered (see, for example, Patent Document 1). However, this is realized by controlling the feed-forward gain, and there is no mention of joint viscosity and frequency characteristics, and there is no concept of compliance.

  In addition, a proposal has been made regarding a control device for a mobile robot that can move up and down at a high speed while being able to move up and down in a stable manner while having a simple configuration. This mobile robot controller detects the error between the target landing position and the actual landing position only at a certain time when walking, for example, when the support leg leaves the floor, when moving in an environment where the landing position is restricted, such as stairs. (For example, refer to Patent Document 2). However, this is to generate the next one-step gait based on the position information of the landing point when raising or lowering the stairs, and does not refer to the characteristics of each joint part when raising or lowering the stairs.

  Further, a legged mobile robot has been proposed that expresses a predetermined action sequence using a basic motion unit composed of time-series motions of each joint and a decoding motion unit composed of a combination of basic motions. In this case, the motion modes including walking of the robot are classified into motion units as motion units, and one or more motion units can be combined to realize complex and diverse body motions (see, for example, Patent Document 3). thing). However, there is no particular mention regarding the characteristics that should be exhibited by the joint actuator and its servo controller when the aircraft is turning.

JP-A-7-205069 JP-A-6-63876 JP 2002-210680 A

  The object of the present invention is to perform stable and highly efficient operation by dynamically or statically controlling the characteristics of the actuator itself and the characteristics of the actuator controller when performing various operations such as walking of the robot. It is an object of the present invention to provide an excellent robot apparatus that can realize the above.

  A further object of the present invention is to realize stable and highly efficient operation by dynamically or statically controlling the characteristics of the actuator itself and the characteristics of the servo controller of the actuator at the time of performing the raising / lowering operation of the staircase. An object of the present invention is to provide an excellent biped walking robot device.

  The object of the present invention is to realize a stable and highly efficient operation by dynamically or statically controlling the characteristics of the actuator itself and the characteristics of the controller of the actuator when performing the turning motion of the aircraft. It is to provide an excellent robot apparatus that can.

The present invention has been made in consideration of the above problems, and is a robot apparatus including a plurality of movable parts,
An actuator for operating the movable part;
Actuator characteristic control means for controlling at least one of gain of servo controller, phase compensation control, and viscous resistance in the actuator;
A robot apparatus comprising: The robot device referred to here is an articulated robot device such as a legged mobile robot, and the actuator corresponds to an actuator for joint drive.

  According to the present invention, in the servo controller of the actuator that constitutes each joint part of the legged mobile robot, by adjusting the proportional gain and the phase compensation element, the positioning accuracy required for each part of the joint of the robot, mechanical passive (Compliance) and operation speed can be set arbitrarily.

  In addition, when the coil of the actuator / motor is not energized, the coil is intermittently switched to a short circuit state or an open state, thereby adjusting the viscous resistance of the motor and changing the robustness against disturbances such as vibration.

  Furthermore, by combining the gain and phase compensation control in the servo controller of these actuators with the control of the viscous resistance of the actuator and motor, the frequency characteristics of the actuator that can be applied to the parts where positioning accuracy is important, or high-speed response Thus, it is possible to obtain the frequency characteristics of the actuator that can be applied to a portion where compliance is important.

  Here, the actuator characteristic control means sets the actuator characteristics to “large low-frequency gain”, “small phase advance amount in high-frequency region”, and “large joint viscous resistance”. Accurate positioning control is possible, and posture stability is increased. In addition, the actuator characteristic control means can set the characteristics of the actuator to “low gain in the low band”, “increase the phase advance amount”, and “decrease the viscous resistance of the joint”, so that the mechanical passivity is fast. Since responsiveness can be provided, high-band follow-up control can be performed while reducing the impact force at the moment of landing.

  For example, by applying such actuator characteristics to the free leg, it is possible to impart mechanical passivity to the leg. Therefore, when the leg is swung up during the walking movement, the potential energy is moved down to assist the movement. It becomes easy to use as energy. As a result, energy consumption is reduced, and consumption of the battery for driving the aircraft can be suppressed.

  The actuator characteristic control means includes a first actuator characteristic that increases the low-frequency gain, decreases the phase advance amount, and increases the joint viscous resistance at each stage of the legged movement operation. Alternatively, the low-pass gain may be decreased, the phase advance amount may be increased, and the second actuator characteristic may be switched to decrease the joint viscous resistance.

  For example, in the stage of starting the walking motion, the actuator characteristic control means includes a knee joint pitch axis, an ankle roll axis and a pitch axis, a trunk roll axis, a pitch axis and a yaw axis, a hip joint roll axis and a pitch axis, and a neck pitch axis. The actuator characteristics of each joint part are set to increase the low-frequency gain, reduce the phase advance amount in the high-frequency region, and increase the joint viscous resistance, and control each joint part with high accuracy. To improve posture stability. In addition, with regard to the characteristics of the joint actuators of the shoulder pitch axis and elbow pitch axis, the low-frequency gain is set small, the phase advance amount is set large, and the viscous resistance of the joint is set small. Try to have sex.

  Further, the actuator characteristic control means is configured such that when the free leg is lifted and the floor reaction force received by the sole becomes zero, the knee joint pitch axis on the free leg side, the ankle roll axis, and the actuator of the pitch axis are controlled. By setting the low-frequency gain, increasing the phase advance amount, and reducing the joint's viscous resistance to the characteristics, mechanical passiveness and quick response are provided, and the impact force at the moment of landing is reduced. It is possible to perform high-band follow-up control while relaxing.

  Further, the actuator characteristic control means may be configured such that when the walking motion of the free leg progresses and the free leg is landed and the floor reaction force received by the sole becomes substantially the same as that during the both-leg support period, For the characteristics of each actuator of the knee joint pitch axis and ankle roll axis and pitch axis on the side, by setting the gain in the low range, decreasing the phase advance amount in the high frequency range, and increasing the viscous resistance of the joint, Enables high-precision positioning control of the free leg when landing.

  In addition, by applying such actuator characteristics to the shoulder to the free leg, it is possible to impart mechanical passivity to the leg, so that the potential energy when the leg is swung up during the walking movement is lowered during the next movement. It becomes easy to use as energy for operation assistance. As a result, energy consumption is reduced, and consumption of the battery for driving the aircraft can be suppressed.

  Here, the actuator characteristic control means sets the actuator characteristics to “large low-frequency gain”, “small phase advance amount in high-frequency region”, and “large joint viscous resistance”. Accurate positioning control is possible, and posture stability is increased. Therefore, in each stage of the walking motion, the first actuator that increases the low-frequency gain, the phase advance amount, and the joint viscous resistance increases the characteristics of the actuator for driving each joint for which positioning accuracy is prioritized. It is good to set to the characteristic.

  In addition, the actuator characteristic control means can set the characteristics of the actuator to “low gain in the low band”, “increase the phase advance amount”, and “decrease the viscous resistance of the joint”, so that the mechanical passivity is fast. Since responsiveness can be provided, high-band follow-up control can be performed while reducing the impact force at the moment of landing. Therefore, at each stage of walking motion, the characteristics of the actuator for driving each joint where mechanical passiveness or high-speed response is prioritized, the low-frequency gain is reduced, the phase advance amount is increased, and the joint viscous resistance is increased. It is preferable to set the second actuator characteristic to be reduced.

  The airframe of the legged mobile robot is composed of a multi-link structure in which a plurality of joint axes having substantially parallel joint degrees of freedom are connected in the length direction. During the walking operation, the link state formed by the landing site of the multi-link structure and the floor surface is switched several times between the open link state and the closed link state. In each stage where the link state is switched in this way, the characteristics prioritized by the actuator for driving each joint are switched among positioning accuracy, mechanical passivity or high-speed response, and accordingly, the first Switching between the actuator characteristic and the second actuator characteristic may be performed.

  Further, the actuator characteristic control means has a large low-frequency gain and a phase in a high frequency region with respect to the characteristics of the actuators of all joint parts at the stage of supporting both legs before ascending or descending the stairs in the stair ascending / descending operation. A setting is made to decrease the advance amount and increase the viscous resistance of the joint.

  Next, at the stage where the first step is taken to ascend or descend the stairs, the low range gain is reduced and the phase advance amount is reduced with respect to the characteristics of the knee joint pitch axis on the free leg side and the ankle roll axis and pitch axis actuators. To increase the joint viscosity resistance.

  Next, at the stage where the foot of the first step is landed one step above or below the stairs, the low-frequency gain is increased and the phase advance amount is reduced in the high-frequency region with respect to the characteristics of the actuators of all joint parts. Set to increase viscous resistance.

  Next, the foot that is landing one step above or below becomes the support leg, and at the stage where the second step, which was the support leg, is pulled up, for the characteristics of each actuator of the ankle roll axis and pitch axis on the free leg side, A setting is made to reduce the low-frequency gain, increase the phase advance amount, and reduce the joint viscous resistance.

  Next, the foot that is landing one step above or below becomes the support leg, and at the stage where the second step, which was the support leg, is pulled up, for the characteristics of each actuator of the ankle roll axis and pitch axis on the free leg side, A setting is made to reduce the low-frequency gain, increase the phase advance amount, and reduce the joint viscous resistance.

  Here, the actuator characteristic control means sets the actuator characteristics to “large low-frequency gain”, “small phase advance amount in high-frequency region”, and “large joint viscous resistance”. Accurate positioning control is possible, and posture stability is increased. Therefore, in each stage of the stair ascending / descending operation, the characteristics of the actuator for driving each joint where positioning accuracy is given priority are as follows: the low-frequency gain is increased, the phase advance amount is decreased, and the joint viscous resistance is increased. Set to actuator characteristics.

  In addition, the actuator characteristic control means can set the characteristics of the actuator to “low gain in the low band”, “increase the phase advance amount”, and “decrease the viscous resistance of the joint”, so that the mechanical passivity is fast. Since responsiveness can be provided, high-band follow-up control can be performed while reducing the impact force at the moment of landing. Therefore, at each stage of the stair climbing operation, the characteristics of the actuator for driving each joint where mechanical passiveness or high-speed response is prioritized, the low-frequency gain is small, the phase advance amount is large, the joint viscous resistance is It is good to set to the 2nd actuator characteristic which makes small.

  The airframe of the legged mobile robot is composed of a multi-link structure in which a plurality of joint axes having substantially parallel joint degrees of freedom are connected in the length direction. In the course of the stair ascending / descending operation, the link state formed by the landing part of the multi-link structure and the floor surface is switched several times between the open link state and the closed link state. In each stage where the link state is switched in this way, the characteristics prioritized by the actuator for driving each joint are switched among positioning accuracy, mechanical passivity or high-speed response, and accordingly, the first Switching between the actuator characteristic and the second actuator characteristic may be performed.

  Further, the actuator characteristic control means, at the stage of starting the turning motion of the aircraft, increases the low-frequency gain with respect to the characteristics of the actuators of all joint parts constituting the aircraft, and reduces the phase advance amount in the high-frequency region, A setting is made to increase the viscous resistance of the joints, and each of these joint parts can be positioned with high accuracy, and posture stability is increased.

  Further, the actuator characteristic control means is configured such that when the free leg is lifted and the floor reaction force received by the sole becomes zero, the knee joint pitch axis on the free leg side, the ankle roll axis, and the actuator of the pitch axis are controlled. By setting the low-frequency gain, increasing the phase advance amount, and reducing the joint's viscous resistance to the characteristics, mechanical passiveness and quick response are provided, and the impact force at the moment of landing is reduced. It is possible to perform high-band follow-up control while relaxing.

  In addition, the actuator characteristic control means may be configured such that when the swinging motion proceeds and the free leg is landed and the floor reaction force received by the sole becomes substantially the same as that during the both-leg support period, At the time of landing, the joint pitch axis and ankle roll axis and pitch axis actuator characteristics are set by increasing the gain in the low range, decreasing the phase advance amount in the high frequency range, and increasing the viscous resistance of the joint. Enables high-precision positioning control of the free leg.

  In addition, by applying such actuator characteristics to the free leg, it is possible to give mechanical leg to the leg, so that it assists the operation when the potential energy when the leg is swung up during the swiveling motion is swung down next time. It becomes easy to use as energy. As a result, energy consumption is reduced, and consumption of the battery for driving the aircraft can be suppressed.

  Here, the actuator characteristic control means sets the actuator characteristics to “large low-frequency gain”, “small phase advance amount in high-frequency region”, and “large joint viscous resistance”. Accurate positioning control is possible, and posture stability is increased. Therefore, at each stage of the turning operation, the characteristics of the actuator for driving each joint where positioning accuracy is given priority are the first actuator that increases the low-frequency gain, decreases the phase advance amount, and increases the joint viscous resistance. It is good to set to the characteristic.

  In addition, the actuator characteristic control means can set the characteristics of the actuator to “low gain in the low band”, “increase the phase advance amount”, and “decrease the viscous resistance of the joint”, so that the mechanical passivity is fast. Since responsiveness can be provided, high-band follow-up control can be performed while reducing the impact force at the moment of landing. Therefore, at each stage of the turning motion, the characteristics of the actuator for driving each joint where mechanical passiveness or high-speed response is prioritized, the low-frequency gain is reduced, the phase advance amount is increased, and the joint viscous resistance is increased. It is preferable to set the second actuator characteristic to be reduced.

  The airframe of the legged mobile robot is composed of a multi-link structure in which a plurality of joint axes having substantially parallel joint degrees of freedom are connected in the length direction. In the course of the turning operation, the link state formed by the landing part of the multi-link structure and the floor surface is switched several times between the open link state and the closed link state. In each stage where the link state is switched in this way, the characteristics prioritized by the actuator for driving each joint are switched among positioning accuracy, mechanical passivity or high-speed response, and accordingly, the first Switching between the actuator characteristic and the second actuator characteristic may be performed.

  According to the present invention, stable and highly efficient operation can be achieved by dynamically or statically controlling the characteristics of the actuator itself and the characteristics of the actuator controller when performing various operations such as walking of the robot. An excellent robot apparatus that can be realized can be provided.

  According to the present invention, in each stage of the robot's walking motion, the actuator of each joint part has a first actuator characteristic that increases the low-frequency gain, decreases the phase advance amount, and increases the joint viscous resistance; By dynamically switching between the second actuator characteristics that reduce the low-frequency gain, increase the phase advance amount, and decrease the viscous resistance of the joint, the potential energy when the leg is swung up during the walking motion is It becomes easy to use as energy for assisting operation during the swing-down operation. As a result, energy consumption is reduced, and the consumption of the battery as the power source for driving the body is also reduced.

  According to the present invention, in each stage of the stair ascending / descending operation, the actuator of each joint part has a first actuator characteristic that increases the low-frequency gain, decreases the phase advance amount, and increases the joint viscous resistance; By dynamically switching between the second actuator characteristics that reduce the low-frequency gain, increase the phase advance amount, and decrease the viscous resistance of the joint, the potential energy when the leg is swung up during the lifting operation is It becomes easy to use as energy for assisting operation during the swing-down operation. As a result, energy consumption is reduced, and consumption of the battery for driving the aircraft can be suppressed.

  Further, according to the present invention, at each stage of the turning motion of the airframe, the first actuator characteristics for increasing the low-frequency gain, decreasing the phase advance amount, and increasing the joint viscous resistance, By dynamically switching between the second actuator characteristics that reduce the low-frequency gain, increase the phase advance amount, and decrease the viscous resistance of the joint, the potential energy when the leg is swung up during the turning motion is It becomes easy to use as energy for assisting operation during the swing-down operation. As a result, energy consumption is reduced, and the consumption of the battery as the power source for driving the body is also reduced.

  Other objects, features, and advantages of the present invention will become apparent from more detailed description based on embodiments of the present invention described later and the accompanying drawings.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

A. From the front and rear of each how the legged mobile robot is upright is subjected to an "humanoid" or "human-type" of the present invention the mechanical configuration diagram 1 and 2 of the legged mobile robot It shows a view. As shown in the figure, the legged mobile robot includes a torso, a head, left and right upper limbs, and left and right lower limbs that perform legged movement. For example, a control unit ( (Not shown) is designed to control the overall operation of the aircraft.

  Each of the left and right lower limbs is composed of a thigh, a knee joint, a shin, an ankle, and a foot, and is connected by a hip joint at the substantially lower end of the trunk. The left and right upper limbs are composed of an upper arm, an elbow joint, and a forearm, and are connected to the left and right side edges above the trunk by shoulder joints. The head is connected to the substantially uppermost center of the trunk by a neck joint.

  The control unit is equipped with a controller (main control unit) that processes the external inputs from each joint actuator and sensors (described later) that constitute this legged mobile robot, and a power supply circuit and other peripheral devices. It is a housing. In addition, the control unit may include a communication interface and a communication device for remote operation. The drive control of the joint actuator mentioned here includes control of the servo gain of the actuator and viscosity control in addition to the angular position control, angular velocity control, and angular acceleration of the joint angle.

  The legged mobile robot configured as described above can realize bipedal walking by whole body cooperative operation control by the control unit. Such biped walking is generally performed by repeating a walking cycle divided into the following operation periods. That is,

(1) Single leg support period with left leg lifted right leg (2) Both leg support period with right leg grounded (3) Single leg support period with right leg lifted with left leg (4) Both legs with left leg grounded Support period

  The walking control in the legged mobile robot is realized by planning the target trajectory of the lower limb in advance and correcting the planned trajectory in each of the above periods. That is, in the both-leg support period, the correction of the lower limb trajectory is stopped, and the waist height is corrected at a constant value using the total correction amount with respect to the planned trajectory. In the single leg support period, a corrected trajectory is generated so that the relative positional relationship between the corrected ankle and waist of the leg is returned to the planned trajectory.

  In general, ZMP is used as a norm for determining the stability of walking for posture stability control of the aircraft, including correction of walking motion trajectory. That is, the calculation is performed by interpolation calculation using a fifth-order polynomial so that the position, velocity, and acceleration for reducing the deviation from ZMP are continuous. The standard for discriminating the stability by ZMP is the principle of d'Alembert that gravity and inertia force from the walking system to the road surface, and these moments balance with the floor reaction force and the floor reaction force moment as a reaction from the road surface to the walking system. based on. As a result of dynamic reasoning, there is a point where the pitch axis and roll axis moments become zero, that is, ZMP (Zero Moment Point) inside the support polygon formed by the sole contact point and the road surface.

  FIG. 3 schematically shows an example of the configuration of the joint degrees of freedom that the legged mobile robot has. As shown in the figure, a legged mobile robot is a body that connects an upper limb including two arms and a head 1, a lower limb comprising two legs that realize a moving operation, and an upper limb and a lower limb. It is a structure provided with a plurality of limbs composed of a trunk.

  The neck joint (Neck) that supports the head has four degrees of freedom: a neck joint yaw axis 1, first and second neck joint pitch axes 2 </ b> A and 2 </ b> B, and a neck joint roll axis 3.

  Each arm portion has a degree of freedom as a shoulder joint pitch axis 4 at the shoulder, a shoulder joint roll axis 5, an upper arm yaw axis 6, an elbow joint pitch axis 7 at the elbow, and a wrist ( Wrist) is composed of a wrist joint yaw axis 8 and a hand portion. The hand part is actually a multi-joint / multi-degree-of-freedom structure including a plurality of fingers.

  The trunk (Trunk) has two degrees of freedom: a trunk pitch axis 9 and a trunk roll axis 10.

  In addition, each leg constituting the lower limb includes a hip joint yaw axis 11 at the hip joint (Hip), a hip joint pitch axis 12, a hip joint roll axis 13, a knee joint pitch axis 14 at the knee (Knee), and an ankle (Ankle). ), An ankle joint pitch axis 15, an ankle joint roll axis 16, and a foot.

  A portion near the waist corresponding to the pelvis that connects the left and right hip joints is called a “base”. Since the mass operation amount is large, the base body is an important control target point in the posture stability control of the legged mobile robot.

B. Control System Configuration of Legged Mobile Robot FIG. 4 schematically shows a control system configuration of the legged mobile robot 100. As shown in the figure, the legged mobile robot 100 includes each of the mechanism units 30, 40, 50R / L, 60R / L representing human limbs, and adaptive control for realizing a cooperative operation between the mechanism units. (Where R and L are suffixes indicating right and left, respectively, and so on).

  The entire operation of the legged mobile robot 100 is controlled by the control unit 80 in an integrated manner. The control unit 80 exchanges data and commands between a main control unit 81 configured by main circuit components (not shown) such as a CPU (Central Processing Unit) and a memory, and each component of the power supply circuit and the robot 100. The peripheral circuit 82 includes an interface (none of which is shown).

  In realizing the present invention, the installation location of the control unit 80 is not particularly limited. In the example shown in FIG. 4, it is mounted on the trunk unit 40, but may be mounted on the head unit 30. Alternatively, the control unit 80 may be provided outside the legged mobile robot 100 so as to communicate with the body of the legged mobile robot 100 by wire or wirelessly.

Each joint degree of freedom in the legged mobile robot 100 shown in FIG. 3 is realized by a motor or other type of actuator corresponding thereto. That is, the head unit 30 includes a neck joint yaw axis actuator A ₁ representing the neck joint yaw axis 1, the first and second neck joint pitch axes 2 A and 2 B, and the neck joint roll axis 3. Second neck joint pitch axis actuators A _2A and A _2B and neck joint roll axis actuators A ₃ are respectively disposed.

The trunk unit 40 is provided with a trunk pitch axis actuator A ₉ and a trunk roll axis actuator A ₁₀ that represent the trunk pitch axis 9 and the trunk roll axis 10, respectively.

Further, the arm unit 50R / L is subdivided into an upper arm unit 51R / L, an elbow joint unit 52R / L, and a forearm unit 53R / L, but a shoulder joint pitch axis 4, a shoulder joint roll axis 5, an upper arm Shoulder joint pitch axis actuator A ₄ , shoulder joint roll axis actuator A ₅ , upper arm yaw axis actuator A ₆ , elbow joint pitch axis expressing the degrees of freedom of yaw axis 6, elbow joint pitch axis 7, and wrist joint yaw axis 8 An actuator A ₇ and a wrist joint yaw axis actuator A ₈ are provided.

The leg unit 60R / L is subdivided into a thigh unit 61R / L, a knee unit 62R / L, and a shin unit 63R / L, but the hip joint yaw axis 11, hip joint pitch axis 12, hip joint Hip joint yaw axis actuator A ₁₁ expressing the degree of freedom of each of the roll axis 13, knee joint pitch axis 14, ankle joint pitch axis 15, and ankle joint roll axis 16, hip joint pitch axis actuator A ₁₂ , hip roll axis actuator A ₁₃ , A knee joint pitch axis actuator A ₁₄ , an ankle joint pitch axis actuator A ₁₅ , and an ankle joint roll axis actuator A ₁₆ are provided.

The actuators A ₁ , A ₂ , A ₃ ... Used for each joint are more preferably composed of small AC servo actuators of a gear direct connection type and a servo control system mounted on a motor unit in a single chip. can do. This type of AC servo actuator is disclosed in, for example, Japanese Patent Application Laid-Open No. 2000-299970 (Japanese Patent Application No. 11-33386) already assigned to the present applicant.

  For each mechanism unit such as the head unit 30, trunk unit 40, arm unit 50, and leg unit 60, sub-control units 35, 45, 55, and 65 for actuator drive control are disposed.

  An acceleration sensor 95 and a posture sensor 96 are disposed on the trunk 40 of the body. The acceleration sensor 95 is disposed in the X, Y, and Z axial directions. By locating the acceleration sensor 95 on the waist of the airframe, setting the waist, that is, the base body, which is a part with a large amount of mass operation as the control target point, directly measuring the posture and acceleration at that position, the posture based on ZMP Stable control can be performed.

  In addition, ground check sensors 91 and 92 and acceleration sensors 93 and 94 are disposed on the legs 60R and 60L, respectively. The ground contact confirmation sensors 91 and 92 are configured by, for example, mounting a pressure sensor on the sole, and can detect whether the sole has landed based on the presence or absence of a floor reaction force. The acceleration sensors 93 and 94 are arranged at least in the X and Y axial directions. By disposing the acceleration sensors 93 and 94 on the left and right feet, the ZMP equation can be directly assembled with the feet closest to the ZMP position.

  When the acceleration sensor is placed only on the waist where the mass manipulated variable is large, only the waist, that is, the base, is the direct control target point, and the foot state is relative based on the calculation result of this control target point. Therefore, the following condition must be satisfied between the foot and the road surface.

(1) The road surface does not move no matter what force or torque is applied.
(2) The friction coefficient with respect to translation on the road surface is sufficiently large, and no slip occurs.

  On the other hand, in the present embodiment, a reaction force sensor system (such as a floor reaction force sensor) that directly applies a force to the ZMP is provided on a foot that is a contact portion with the road surface, and local coordinates used for control and the coordinates thereof An acceleration sensor for directly measuring is provided. As a result, the ZMP balance equation can be directly assembled with the foot portion closest to the ZMP position, and more rigorous posture stabilization control can be realized at high speed without depending on the preconditions described above. As a result, the fuselage can be used on gravel where the road surface moves when force or torque is applied, on carpets with long bristle feet, or in residential tiles where sliding friction cannot be secured sufficiently. Can guarantee stable walking (movement).

  The main control unit 80 can dynamically correct the control target in response to the outputs of the sensors 91 to 96. More specifically, whole body motion in which each of the sub-control units 35, 45, 55, and 65 is adaptively controlled and the upper limbs, trunk, and lower limbs of the legged mobile robot 100 are cooperatively driven. Realize the pattern.

The whole body movement on the body of the robot 100 sets the foot movement, the ZMP trajectory, the trunk movement, the upper limb movement, the waist height, and the like, and commands for instructing the movement in accordance with these setting contents. Forward to the units 35, 45, 55, 65. Then, in each of the sub-control section 35, 45 ... interprets the command received from the main control unit 81 outputs a drive control signal to the actuators _{A 1, A 2, A 3} .... ZMP is a point on the floor where the moment due to the floor reaction force during walking is zero, and the “ZMP trajectory” mentioned here means a trajectory in which the ZMP moves during the walking motion period of the robot 100, for example. .

C. Control of actuator characteristics
C-1. Actuation speed of the actuator, mechanically passive legged mobile robot body can be regarded as a multi-link structure in which a plurality of joint axes having approximately parallel joint degrees of freedom are connected in the length direction. In the course of each leg type motion such as walking motion, falling motion, and rising motion from the floor posture, the link state between the landing part and the floor surface of this multi-link structure is between the open link state and the closed link state. To switch several times.

  Japanese Patent Application No. 2001-233691 already assigned to the present applicant discloses a legged mobile robot that performs high-speed repetitive operations between a closed link state and an open link state with respect to the outside world and work objects. Yes. That is, in a robot having limbs composed of one or more rotary joints (which may have two or more degrees of freedom per joint), the minimum number of passive degrees of freedom necessary to remove the dynamic closure error for each limb. (Decelerator backlash, etc.) and manage the range of movement of each limb appropriately. Even if the actuator that drives the joint does not have a means for acquiring torque information, a high-speed switching operation between the closed link state and the open link state is stably realized. Such a high-speed switching operation between the closed link state and the open link state is performed by placing a geared motor with a small backlash amount in a part close to the waist reference coordinates in a biped walking robot, and back in a part close to the hand / tip. This can be realized by arranging geared motors with a large amount of rush and obtaining optimum characteristics, so that the robot design can be optimized.

  In addition, as a second method for optimizing the robot with respect to the switching of the link state during the operation period, the position error deviation amount can be adjusted by arbitrarily adjusting the open loop gain of the position servo compensator in each joint axis actuator. To control. In other words, when the backlash amount is uniform, the servo deviation due to the servo gain is considered as the backlash amount, and by controlling it, a passive degree of freedom for removing the dynamic closing error can be obtained. .

  In the present embodiment, the latter optimization method is further expanded to adjust not only the proportional gain of the servo controller but also the phase compensation element at each joint part.

  FIG. 5 shows the configuration of the servo controller of the actuator. As shown in the figure, the servo controller has two control elements, a proportional gain K for series compensation and a phase compensation element C (s), and adjusts not only the proportional gain but also the phase compensation element at each joint part. FIG. 6 shows the frequency characteristics of the gain and phase of the transfer function expression model for the motor and reducer shown in FIG.

Here, the phase compensation element is expressed by the following equation. However, n and m are arbitrary natural numbers, and a _i and b _i are arbitrary real numbers. When state variables are expressed, they correspond to feedback gains. S is a Laplace operator.

  Moreover, the transfer function expression model G (s) of the motor and the speed reducer is expressed by the following expression. Where K is the motor gain, J is the moment of inertia of the motor, and D is the viscous resistance coefficient of the motor.

  First, in the servo controller shown in FIG. 5, as an example of designing the phase compensation type control, the phase compensation band is arbitrarily selected (the phase compensation amount is constant and the frequency band is arbitrarily selected) with reference to FIG. While explaining. In the figure,

(1) C (s) -1: A gain amplification of about +5.6 dB and a phase advance of about +18 deg are given in a band of 1.0 to 100 Hz.
(2) C (s) -2: A gain amplification of about +5.6 dB and a phase advance of about +18 deg are given in a band of 0.1 to 10 Hz.
(3) C (s) -3: gain amplification of about +5.6 dB and phase advance of about +18 deg in a band of 10 to 1 kHz.

  As described above, the frequency characteristics of the actuator can be freely set by arbitrarily selecting the frequency band to which the phase compensation is performed. Therefore, the joint axis of the robot constituted by such an actuator can dynamically adjust the frequency characteristics according to the posture of the airframe and the situation of the operation.

  In the example shown in FIG. 7, an example of phase lead compensation is shown. However, in the case of phase delay compensation, any phase delay amount can be set in any frequency band.

  Next, in the servo controller shown in FIG. 5, as an example of designing the phase compensation type control, the amount of phase compensation is arbitrarily selected (the frequency compensation is constant and the phase compensation amount is arbitrarily selected). The description will be given with reference. In the figure,

(4) C (s) -4: Gain amplification of about +3.5 dB and a phase advance of about +12 deg in a band of 4.0 to 70 Hz.
(5) C (s) -5: A gain amplification of about +5.6 dB and a phase advance of about +18 deg are given in the band of 2.0 to 70 Hz.
(6) C (s) -6: A gain amplification of about +6.5 dB and a phase advance of about +21 deg are given in the band of 1.0 to 70 Hz.

  Thus, the frequency characteristic of the actuator can be freely set by arbitrarily selecting the amount of phase compensation. Therefore, the joint axis of the robot constituted by such an actuator can dynamically adjust the frequency characteristics according to the posture of the airframe and the situation of the operation.

  In the example shown in FIG. 8, an example of phase lead compensation is shown. However, in the case of phase delay compensation, any phase delay amount can be set in any frequency band.

  Next, a design example of a controller that changes the magnitude of the series compensation gain indicated by K in the servo controller shown in FIG. 5 will be described with reference to FIG. This figure corresponds to the fact that K is raised and lowered by ± 3 dB in FIG. As shown in the figure, the magnitude of the series compensation gain can be arbitrarily set.

  In order to apply the contents shown in FIGS. 7 to 9 to the actuator for driving the joint axis of the robot, a communication protocol for dynamically or statically changing the parameters constituting these controllers is implemented. Thereby, various characteristics can be given to each joint axis of the robot.

  Next, the characteristics of the actuator when the servo controller for the actuator having these characteristics is mounted will be described.

  FIG. 10 shows an open loop characteristic when the servo controller of the actuator is mounted so as to arbitrarily select the frequency band with a constant phase compensation amount as shown in FIG.

(1) C (s) -1: Gives a gain amplification of about +5.6 dB and a phase advance of about +18 deg in a band of 1.0 to 100 Hz. As a result, the gain is increased overall, so that positioning accuracy and followability are improved, but energy loss is likely to occur. Moreover, it may become unstable when the load increases.
(2) C (s) -2: Gain amplification of about +5.6 dB and phase advance of about +18 deg in a band of 0.1 to 10 Hz. In this case, it has an intermediate characteristic between C (s) -1 and C (s) -2.
(3) C (s) -3: Gives a gain amplification of about +5.6 dB and a phase advance of about +18 deg in a band of 10 to 1 kHz. In this case, phase lead compensation is performed only in the high frequency range, so that the effect is not so much seen during slow operation, but it is effective for fast operation such as running, flying, and dancing.

  As described above, the frequency characteristics of the actuator can be freely set by arbitrarily selecting the frequency band to which the phase compensation is performed. Therefore, the joint axis of the robot constituted by such an actuator can dynamically adjust the frequency characteristics according to the posture of the airframe and the situation of the operation.

  Further, FIG. 11 shows a state in which the control of the series compensation gain is further adopted in Example C (s) -3 in which the phase lead compensation is performed only in the high frequency region shown in FIG. In this case, as in the example shown in FIG. 5, the gain increases and decreases in the same phase.

  In the example shown in FIG. 10, the phase compensation example C (s) -3 is not very effective during a slow operation, but as shown in FIG. 11, by increasing the gain in the low frequency band, The control deviation can be reduced. As a result, it is possible to respond to the command value with a small delay even during slow operation.

  To summarize these, first, with respect to the open-loop characteristics of the actuator position control system, as shown in FIG. 12, by setting the characteristics so as to increase the overall gain and reduce the phase advance amount in the high range, It is possible to harden the parts and joints that require positional accuracy, such as support legs, and eliminate compliance.

In contrast, with respect to the open loop characteristic of the position control system of the actuator, as shown in FIG. 13, by setting the characteristics as in the low range and low gain, increases the amount of phase lead in the mid-high range, Yu It is possible to obtain a joint part that requires a restraint response rather than the position accuracy of the leg or the like, or a characteristic that is suitable when the joint requires compliance.

  As described above, the mechanism for adjusting not only the proportional gain of the servo controller but also the phase compensation element in each part of the joint in the servo controller of the actuator has been described. Thus, in order to realize a stable and highly efficient operation, it is possible to increase or decrease the force locally and increase or decrease the compliance (mechanical passivity) of each joint part.

  For example, when capturing the motion of each joint axis as a position control system, it is better to use a high gain and high bandwidth servo controller to control the control deviation to be small, but when capturing as a dynamic model In consideration of the action of potential energy and kinetic energy, it is preferable to lower the gain or raise and lower the frequency band for phase compensation.

C-2. Viscous resistance of actuator / motor In addition to the characteristics of actuator operating speed and mechanical passivity during operation as described in the above section C-1, a method of variably controlling the viscous resistance of the actuator can be adopted. .

  For example, a motor of a type that generates rotational torque by controlling a current supplied to a coil to form a predetermined magnetic flux distribution generally includes a first transistor switch group that connects a coil terminal to a power supply voltage, and a coil A switching operation circuit composed of a second transistor / switch group that grounds a terminal is driven by PWM control, thereby controlling a coil current to obtain a desired torque, rotational position, rotational speed, or the like.

  Here, at the timing when the motor coil is in the open state during the non-energized period, the current (strictly charge) energized to the motor coil is lost, resulting in a torque loss. Further, it is easily affected by torque unevenness due to cogging.

  In such a case, even when the motor / coil is not energized, the current (electrically charged) energized to the motor / coil cannot be removed by forming a short-circuit state in which the coil is not open. Can be. At this time, a counter electromotive force is generated in the motor coil due to the magnetic flux density from the permanent magnet side. Since the counter electromotive force causes a force in the direction opposite to the rotation direction of the motor, a viscous resistance against rotation by an external force can be created, and an effect similar to a brake can be obtained. By such viscous resistance to the motor, there is no torque loss and the influence of torque unevenness due to cogging is reduced.

  On the other hand, when a short circuit state of such a coil is formed when the motor is de-energized, as described above, a kind of viscous resistance can be given to the motor, but when such a motor is used for a robot, Due to the influence of the brake due to the coil short, there is a problem that compliance (mechanical passivity) is lost.

  Therefore, by adjusting the ratio of the coil open state and short-circuit state period when the motor coil is not energized according to the desired mechanical characteristics, the motor coil at the timing when the motor coil is opened Compliance (mechanically passive) due to torque loss due to loss of energized current (strictly charge), torque unevenness due to cogging, and brake effect due to coil short when motor / coil is not energized The problem of disappearing) can be solved together.

  Here, the ratio of energization and de-energization of the motor / coil can be realized by PWM control, but the ratio of the open / short-circuit period of the coil in the de-energization of the motor / coil is also the same. It can be realized using PWM control.

  FIG. 14 shows a configuration example of an equivalent circuit of a current control circuit for supplying coil current in a DC motor to which a coil current control mechanism is applied.

The current control circuit shown in the figure has a full-bridge configuration, and a circuit in which a pnp transistor A ′ and an npn transistor A are connected in a forward direction, and a pnp transistor B ′ and an npn transistor B are sequentially connected. The direction-connected circuits are connected in parallel between the power supply voltage _Vcc and the ground GND, and the intermediate points of the transistors A ′ and A and the intermediate points of the transistors B ′ and B are connected by a single-phase coil of the stator.

  When the transistors A ′ and B are turned on and the transistors A and B ′ are turned off, the current Im flows in the motor coil in the direction indicated by the arrow. Further, by turning off the transistors A ′ and B, the coil is opened and the current Im does not flow. Further, by turning off the transistors A ′ and B and turning on the transistors A ′ and B ′, the motor coil is short-circuited.

  The PWM control logic circuit generates a current command to the coil based on a current axis current command (or torque command) from a central control unit (not shown), and performs switching control of each transistor by the PWM method based on the current command. . That is, the energizing period in which the transistors A ′ and B are turned on and the transistors A and B ′ are turned off to flow the coil current Im and the non-energizing period in which the transistors A ′ and B are turned off and the coil is de-energized are alternated. To generate.

  In the present embodiment, an additional logic circuit is provided for switching the control signals for controlling the on / off operations of the transistors A and A ′ and the arrangements B and B ′ output from the PWM control logic circuit using the additional logic.

The additional logic circuit controls the on / off operation of the signals A ₀ and A ₀ ′ and B ₀ and B ₀ ′ output from the PWM control logic circuit based on the BRAKE_PWM control signal output from the PWM control logic circuit. The control logic is switched by additional logic. Thus, the switching operation between the open state and the short-circuit state of the coil in the non-energized state of the motor / coil is performed. FIG. 15 shows a specific circuit configuration of the additional logic circuit.

A transistor A 'signal A ₀ for control' from PWM control logic and the logical product of the transistor B 'signal B ₀ for control', signal A ₀ of the control transistor A and the transistor B control signal B ₀ of An exclusive OR is taken, and the logical product of these logical operation values is inverted and logically ORed with the inverted signal of the BRAKE_PWM control signal. A logical product of the result of the logical sum with the original transistor control signals is the final transistor control signal.

Additional logic circuit, when a high level is input to the BRAKE_PWM control signal switches the transistor control signal so as to short the coil when the coil is de-energized. When the coil is not normally energized, the PWM control logic circuit outputs a transistor control signal that makes the control signals A ₀ ′ and B ₀ ′ high and A ₀ and B ₀ low. On the other hand, when a high level BRAKE_PWM control signal is input, the additional logic circuit turns A ₁ ′ and B ₁ ′ in the high state to low to form a short circuit state of the coil.

  On the other hand, when the BRAKE_PWM control signal is in the low state, the additional logic circuit outputs the transistor control signal from the PWM control logic circuit as it is when the coil is not energized, so that the coil is in the open state when deenergized.

  FIG. 16 shows the output characteristics of each transistor control signal of the additional logic circuit together with the coil current waveform characteristics and torque output characteristics when a BRAKE_PWM control signal having a predetermined duty ratio is input by PWM control. Yes.

  When the coil is short-circuited when the coil is not energized, the time until the coil current returns to zero becomes longer due to the transient response, but when the coil is opened, the time becomes shorter. The transient response characteristics when the coil is not energized are a mixture of these characteristics according to the duty ratio of the BRAKE_PWM control signal.

  Therefore, as shown in the figure, when the switching operation of coil energization and coil short circuit is repeated, the next energization is started before the coil current returns to zero when the coil is not energized. At this time, the maximum current of the coil gradually increases every time the coil is energized and de-energized, and the increasing tendency is almost proportional to the duty ratio, that is, the ratio at which the BRAKE_PWM control signal becomes high level. Similarly, the effective value of the coil current gradually increases as shown in the figure, but the increasing tendency is substantially proportional to the duty ratio, that is, the ratio at which the BRAKE_PWM control signal becomes high level.

Further, the output torque T of the motor, since a value obtained by multiplying the torque constant K _t of the motor coil current _{(T = K t · I)} , as can be seen from the figure, repeated coil energization and non-energization When the coil current increases, the effective value of the motor torque increases. Therefore, when the motor coil is not energized, a short-circuit state occurs, so that the current (strictly charge) energized to the motor coil is not lost and torque loss is eliminated. Further, it is less susceptible to torque unevenness due to cogging.

  The upward trend when the coil energization and the non-energization are repeated is substantially proportional to the duty ratio of the BRAKE_PWM control signal, that is, the ratio at which the control signal becomes high level. The characteristic that the output of the motor torque increases corresponds to the viscosity coefficient of the motor.

  When such a short circuit state of the coil is formed when the motor is not energized, as described above, a kind of viscous resistance can be given to the motor. On the other hand, when such a motor is used for a robot, there is a problem that compliance (mechanical passivity) is lost due to the influence of a brake caused by a coil short circuit.

  Therefore, the PWM control logic circuit controls the ratio of the period between the open state of the coil and the short-circuit state in the non-energized state of the motor coil by performing PWM control on the BRAKE_PWM control signal input to the additional logic circuit.

  When PWM control is performed for the open and shorted periods of the coil when the motor / coil is not energized, the coil current characteristics are the transient response characteristics of the coil current and the coil when the coil is opened when the coil is not energized. The characteristics of the transient response characteristics of the coil current when the is short-circuited are mixed according to the duty ratio.

  FIG. 17 shows the output characteristics of each transistor control signal of the additional logic circuit together with the coil current waveform characteristics and torque output characteristics when a BRAKE_PWM control signal having a predetermined duty ratio is input by PWM control. .

  When the coil is short-circuited when the coil is not energized, the time until the coil current returns to zero becomes longer due to the transient response, but when the coil is opened, the time becomes shorter. The transient response characteristics when the coil is not energized are a mixture of these characteristics according to the duty ratio of the BRAKE_PWM control signal.

  Therefore, as shown in the figure, when the switching operation of coil energization and coil short circuit is repeated, the next energization is started before the coil current returns to zero when the coil is not energized. At this time, the maximum current of the coil gradually increases every time the coil is energized and de-energized, and the increasing tendency is almost proportional to the duty ratio, that is, the ratio at which the BRAKE_PWM control signal becomes high level. Similarly, the effective value of the coil current gradually increases as shown in the figure, but the increasing tendency is substantially proportional to the duty ratio, that is, the ratio at which the BRAKE_PWM control signal becomes high level.

Further, the output torque T of the motor, since a value obtained by multiplying the torque constant Kt of the motor coil current _{(T = K t · I)} , as can be seen from the figure, when repeated coil energization and non-energization As the coil current increases, the effective value of the motor torque increases. The upward tendency at this time is substantially proportional to the duty ratio of the BRAKE_PWM control signal, that is, the ratio at which the control signal becomes high level. The characteristic that the output of the motor torque increases corresponds to the viscosity coefficient of the motor. In other words, the viscous resistance of the motor can be dynamically controlled by the duty ratio of the BRAKE_PWM control signal.

  In this way, the duty ratio of the BRAKE_PWM control signal supplied from the PWM control logic circuit to the additional logic circuit is PWM controlled, so that the ratio of the open state and the shorted state of the coil when the motor / coil is not energized can be set to a desired value. It can be adjusted according to the mechanical properties.

  Therefore, there is a problem of torque loss due to loss of current (electrically, electric charge) applied to the motor coil at the timing when the motor coil is in an open state, torque unevenness due to cogging, and deenergization of the motor coil. The problem of loss of compliance (mechanical passivity) due to the effect of braking due to a coil short at the time can be solved together.

  Further, as described above, the viscous resistance of the motor can be dynamically controlled by the duty ratio of the BRAKE_PWM control signal. The control relationship is shown in FIG. In the figure, the viscous resistance is represented by the product of the viscosity coefficient [mN−m · s / rad] and the rotational angular velocity [rad / s] during operation.

  The area indicated by A in FIG. 18 corresponds to the maximum viscosity coefficient in the motor characteristics, and is 0.9 mN-m · s / rad in the illustrated example. When the actuator characteristics are set in this region, the joint viscosity increases. As a result, although compliance cannot be obtained, it is possible to realize control characteristics that are robust against disturbances such as external vibrations.

  On the other hand, a region indicated by B in FIG. 18 corresponds to a viscosity coefficient that is 1/3 or less of the maximum value on the motor characteristics, and is 0.15 mN-m · s / rad in the illustrated example. When the actuator characteristics are set in this region, the joint viscosity becomes small. As a result, it becomes weak against disturbance, but mechanical passivity (compliance) can be obtained.

  The region B for obtaining the compliance may basically be equal to or less than the maximum value on the motor characteristics, but as shown in the drawing, the inclination around 0.3 to 0.8 mN-m · s / rad is Steep portions are easily affected by environmental changes such as temperature, making control difficult. For this reason, as described above, it is considered appropriate to set the region where the inclination is gentle at a third or less of the maximum value on the motor characteristics as the mechanical passive region. Has been proved by experiments.

  In the above description, a DC motor has been described as an example, but the same applies to a three-phase motor and other types of motors that generate rotational torque by forming a predetermined magnetic flux distribution by controlling the current supplied to other coils. In addition, a desired viscous resistance of the motor can be obtained by intermittently switching the motor coil during non-energization between an open state and a short-circuit state.

D. Application to Legged Mobile Robot Next, a bipedal legged mobile robot in which the characteristics control mechanism of the actuator servo controller and the actuator characteristic control mechanism according to this embodiment is applied to each joint part will be described.

  As described above, in the servo controller of the actuator, by adjusting the proportional gain and the phase compensation element, the positioning accuracy, mechanical passivity (compliance), and operation speed required for each part of the robot joint are arbitrarily set. be able to. In addition, when the coil of the actuator / motor is not energized, the coil is intermittently switched to a short circuit state or an open state, thereby adjusting the viscous resistance of the motor and changing the robustness against disturbances such as vibration.

  Furthermore, by combining the gain and phase compensation control in the servo controller of these actuators with the control of the viscous resistance of the actuator and motor, the frequency characteristics of the actuator that can be applied to the parts where positioning accuracy is important, or high-speed response Thus, it is possible to obtain the frequency characteristics of the actuator that can be applied to a portion where compliance is important.

  The frequency characteristics of the actuator that can be applied to a portion where positioning accuracy is important are as shown in FIG. In this case, the proportional gain of the servo controller is increased to increase the gain of the entire system so that the gain can be obtained up to the low frequency band. Further, as shown in the figure, the frequency characteristic is such that the amount of phase advance is reduced in the high frequency range, so that stability is ensured although it does not contribute much to high-speed response. In addition, the viscous resistance of the motor is increased so that it is robust against disturbances such as vibration. In short, the characteristics shown in the figure are robust to disturbances such as vibrations with priority given to positioning accuracy.

  Further, the frequency characteristics of the actuator that can be applied to a portion where high-speed response and compliance are important are as shown in FIG. In this case, by reducing the proportional gain and reducing the gain of the entire system, the gain in the low frequency band is reduced, and mechanical passivity (compliance) is easily obtained. Further, as shown in the figure, the frequency characteristic is set so that the phase advance amount becomes large in the middle and high range so as to obtain high-speed response. In addition, the viscous resistance of the motor is reduced to facilitate obtaining mechanical passivity (compliance). In short, the characteristics shown in the figure are characteristics giving priority to mechanical passivity (compliance) and high-speed response.

  The joint degrees of freedom of the legged mobile robot shown in FIGS. 1 to 3 are realized by an actuator including the servo controller described above. That is, the robot is a humanoid robot having two legs and two arms. This robot has limbs attached to the body, a head composed of four degrees of freedom: a neck roll axis, first and second neck pitch axes, and a neck yaw axis, a shoulder joint pitch axis, a shoulder joint roll axis, and a shoulder joint. Left and right arm parts having at least four degrees of freedom, ie, yaw axis and elbow joint pitch axis, trunk part having two degrees of freedom, trunk roll axis and trunk pitch axis, hip joint yaw axis, hip roll axis, hip joint pitch axis The left and right leg portions having at least six degrees of freedom, that is, a knee pitch axis, an ankle pitch axis, and an ankle roll axis.

  Each of these joint degrees of freedom is realized by an actuator including the servo controller described above. An example of controlling the gain / phase compensation characteristics of the actuator used in each joint part will be described in detail below.

(1) Characteristics of the actuator applied to the neck portion In the neck portion, the proportional gain is set high in order to prioritize positioning accuracy. Further, the phase advance amount is set to be small so as not to impair the stability of the increased proportional gain while maintaining the operation speed. Further, in order to obtain robustness against vibration disturbance generated during the operation of the portion below the body, the joint viscous resistance is set large.

(2) Characteristics of the actuator applied to the shoulder and elbow parts When performing continuous motions such as walking and dancing, the actuator is given characteristics that make it more mechanically passive than the positioning characteristics. To make the motion passive, reduce the viscous resistance of the joint. In addition, the proportional gain is set low in order to make the operation passive and reduce energy consumption. In order to increase the operation speed, the phase advance amount is set large in the middle and high range. Some operations only reciprocate like a pendulum. In that case, the mechanical resistance (compliance) is obtained by minimizing the viscous resistance and the proportional gain of the joint, and the mechanical energy is easily used for the operation.

  On the other hand, when an operation using force such as pushing or pulling an object is performed, control is performed so that the positioning accuracy priority characteristic and the mechanical passive characteristic are dynamically switched according to the load torque value. To generate more force with respect to the load torque value, increase the proportional gain and increase the joint viscous resistance. In addition, when performing an operation that makes the load torque value follow a constant load, in addition to the adjustment by the position command value from the upper level, a proportional gain according to the load torque detected by the actuator internal torque sensor To reduce the viscous resistance of the joints to obtain mechanical passivity (compliance).

(3) Characteristics of the actuator applied to the trunk part In order to obtain robustness against vibration disturbance due to own movement, the viscous resistance of the joint is increased. Alternatively, the proportional gain is set high in order to prioritize positioning accuracy. Alternatively, the phase advance amount is set to be small so as not to impair the stability of increasing the proportional gain while maintaining the operation speed.

(4) Characteristics of the actuator applied to the hip joint portion In order to obtain robustness against vibration disturbance due to its own movement, the viscous resistance of the joint is increased. Alternatively, the proportional gain is set high in order to prioritize positioning accuracy. Alternatively, the phase advance amount is set to be small so as not to impair the stability of increasing the proportional gain while maintaining the operation speed.

(5) Characteristics of the actuator applied to the knee portion Control is made so that the mechanical passivity is higher than the positioning accuracy at the time of the free leg and at the moment of landing. To make the motion passive, reduce the viscous resistance of the joint. In addition, the proportional gain is set low in order to make the operation passive and reduce energy consumption. In order to increase the operation speed, the phase advance amount is set large in the middle and high range.

  On the other hand, at the time of the support leg, control is performed so that the positioning accuracy is higher than the mechanical passivity. In order to obtain robustness against vibration disturbance caused by one's own movement, the viscous resistance of the joint is increased. Alternatively, the proportional gain is set high in order to prioritize positioning accuracy. Alternatively, the phase advance amount is set to be small so as not to impair the stability of increasing the proportional gain while maintaining the operation speed.

(6) Characteristics of the actuator applied to the ankle portion Control is made so that the mechanical passivity is higher than the positioning accuracy at the time of the free leg and at the moment of landing. In order to mitigate the impact caused by the landing of the ankle part, the joint viscosity should be set small to obtain mechanical passivity (compliance). In addition, in order to mitigate the impact caused by the landing of the ankle part, the proportional gain is set low to obtain mechanical passivity (compliance). In order to increase the operation speed, the phase advance amount is set large in the middle and high range.

  On the other hand, at the time of the supporting leg, the joint resistance resistance is increased in order to increase the torque generated at the ankle portion and to obtain robustness against vibration disturbance caused by the movement of itself. Further, in order to improve the positioning accuracy of the ankle portion, the proportional gain is set high. Further, the phase advance amount is set to be small so as not to impair the stability of the increased proportional gain while maintaining the operation speed.

E. Example of arrangement of actuator characteristics of each part of the joint of the robot during walking motion As described above, by controlling the characteristics of the servo controller of each joint actuator and the characteristics of the actuator itself, the following results are obtained. be able to.

  That is, as in the actuator characteristics shown in FIG. 12, “increase the low frequency gain” and “decrease the phase advance amount in the high frequency region”, and “increase the joint viscous resistance” as shown in FIG. 18A. By performing the setting, high-accuracy positioning control is possible, and the stability of the posture is increased. On the other hand, the actuator characteristics shown in FIG. 13 are set to “lower the low-frequency gain” and “increase the phase advance amount” and “to reduce the joint viscous resistance” as shown in FIG. 18B. As a result, it is possible to provide mechanical passivity and quick responsiveness, so that high-band follow-up control can be performed while relaxing the impact force at the moment of landing.

  For example, by applying the actuator characteristics shown in FIG. 13 to the free leg, it is possible to impart mechanical passivity to the leg. It becomes easy to use as auxiliary energy. As a result, energy consumption is reduced, and consumption of the battery for driving the aircraft can be suppressed.

  Here, the arrangement of the characteristics of the actuator controller and the actuator itself in each joint part when the robot performs a walking motion will be described with reference to FIG.

  When the robot performs a walking motion, the neck pitch axis, trunk roll axis, trunk pitch axis, trunk yaw axis, hip roll and pitch axis, knee pitch axis on the support leg side, ankle roll and pitch axis High positioning accuracy is required at each joint site.

  Accordingly, in the actuators at these joint sites, the proportional gain of the servo controller is increased to increase the gain of the entire system so that the gain can be obtained up to the low frequency band. As shown in FIG. 12, the frequency characteristic is such that the amount of phase advance is reduced at a high frequency, so that stability is ensured although it does not contribute much to high-speed response. Further, as shown in FIG. 18A, the viscous resistance of the motor is increased so as to be robust against disturbances such as vibration.

  On the other hand, high-speed responsiveness and compliance are important in each joint part of the shoulder pitch axis, the elbow pitch axis, and the knee pitch axis, the ankle roll, and the pitch axis on the swing leg side during walking motion.

  Therefore, by reducing the proportional gain and reducing the gain of the entire system in the actuators at these joint parts, the gain in the low frequency band is reduced, and mechanical passivity (compliance) is easily obtained. Further, as shown in FIG. 13, the frequency characteristic (phase compensation characteristic) is set so that the phase advance amount becomes large in the middle and high range so as to obtain high-speed response. In addition, as shown in FIG. 18B, the viscous resistance of the motor is reduced to facilitate obtaining mechanical passivity (compliance).

  By applying the characteristics of the controller of the actuator as shown in FIG. 13 and the characteristics of the actuator itself to the shoulder to the free leg, mechanical passivity (compliance) can be obtained for the arms and legs. As a result, the potential energy when the leg is swung up during the walking motion can be easily used as motion assist energy during the next swinging motion. As a result, energy consumption is reduced, and the consumption of the battery as the power source for driving the body is also reduced.

  FIG. 20 shows a processing procedure for switching the actuator characteristics of each joint part when the robot performs a walking motion in the form of a flowchart.

  First, with respect to the actuators of the joint parts constituting the joint parts of the knee pitch axis, the ankle roll and the pitch axis, as shown in FIG. 12, the low-frequency gain is large, the phase advance amount is small in the high-frequency region, and As shown in FIG. 18A, setting is made to increase the viscous resistance of the joint. Further, by reducing the proportional gain and reducing the overall gain of the system as shown in FIG. 13 for the actuators of the joint parts constituting the joint parts of the shoulder pitch axis and the elbow pitch axis, the low frequency The gain of the band is reduced, and mechanical passivity (compliance) is easily obtained. FIG. 12 shows the actuators of the joint parts constituting the joint parts of the trunk roll axis, the trunk pitch axis, the trunk yaw axis, the hip joint roll and the pitch axis, and the first neck pitch axis. As shown in FIG. 18A, the low-frequency gain is increased, the phase advance amount is decreased in the high-frequency region, and the joint viscous resistance is increased as shown in FIG. 18A. (Step S1).

  Next, an operation of lifting one leg is executed (step S2).

  Here, when the floor reaction force received at the sole of the leg to be lifted becomes zero (step S3), the support leg supports the free leg and performs a walking motion (step S4).

  Further, on the free leg side, the low-frequency gain is small and the phase advance amount is large as shown in FIG. 13 with respect to the knee joint pitch axis and the ankle roll axis and pitch axis actuators on the free leg side. As shown in 18B, a setting is made to reduce the viscous resistance of the joint (step S5).

  Next, a walking action as a free leg is executed (step S6), and further, the landing action is executed (step S7).

  Here, when the value of the floor reaction force detected at the sole becomes close to the value of the both-leg support period (step S8), the landing operation of the free leg is completed (step S9).

  Then, with respect to the knee joint pitch axis on the free leg side and the ankle roll axis and pitch axis actuators, as shown in FIG. 12, the low-frequency gain is large, the phase advance amount is small in the high-frequency region, and FIG. As shown in FIG. 8, the setting is made to increase the viscous resistance of the joint (step S10).

  When the walking motion is continued as it is (step S11), the free leg is switched to the support leg and the support leg is switched to the free leg (step S12), the process returns to step S2, and the same processing as described above is repeatedly executed.

  On the other hand, when the walking motion is finished (step S11), the entire processing routine is finished.

  The body of a legged mobile robot is composed of a multi-link structure in which a plurality of joint axes having approximately parallel joint degrees of freedom are connected in the length direction. The link state formed by the floor portion and the floor surface is switched between the open link state and the closed link state. FIG. 21 shows a state in which a closed link system is constituted by both legs and the floor surface by supporting both legs in the standing posture. FIG. 22 shows a state in which an open link is constituted by both legs and the floor surface by supporting a single leg in a standing posture.

In this embodiment, at each stage of the walking motion, according to the switching of the link state, the characteristic of the corresponding joint actuator is appropriately switched to a hard joint characteristic, a soft joint characteristic, and an intermediate joint characteristic, thereby being adaptive. Achieves a falling motion. Here, a hard joint characteristics, as well as reduce the amount of phase lead in and high range servo characteristics of the actuator motor with high gain over the entire band, as shown in FIG. 12, a motor characteristic indicating the viscosity of the motor in FIG. 18A It is defined as setting to the maximum value of. Further, the joint characteristics of the intermediate indicates the servo characteristics of the actuator motor with a larger amount of phase lead in and middle high frequency with low gain in the low range, as shown in FIG. 13, the viscosity of the motor in FIG. 18A motor It is defined as setting to the maximum value of the characteristic. As shown in FIG. 13, the soft joint characteristics are such that the servo characteristics of the actuator and the motor are low gain, low gain, and the phase advance amount is high in the middle and high ranges, and the motor viscosity is shown in FIG. 18B. It is defined as setting to 1/3 of the maximum value.

  23 to 28 show how the robot performs a walking motion. In the example shown in each figure, an operation state can be grasped by dividing into 6 stages of A to F.

(A) Both-legs support period In the both-legs support state, the lower limbs and the floor form a closed link system (see FIG. 23). By using own joint angle information, sole force sensor (or contact sensor), and posture sensor, it is possible to confirm both-leg support from its own posture, ground contact state, and motion state (speed / acceleration of each axis).

  At this time, the actuators of all the joint parts of the left and right legs are set to the intermediate joint characteristics, that is, the servo characteristics of the actuator / motor, as shown in FIG. While increasing the viscosity, the motor viscosity is set to the maximum value of the motor characteristics shown in FIG. 18A. As a result, the left and right support legs are capable of high-speed response, and obtain a compliance that is higher than hard characteristics and lower than soft characteristics.

  Also, the left and right shoulder pitches, elbow pitches, and other joint parts have hard joint characteristics, that is, the servo characteristics of the actuator and motor, as shown in FIG. While decreasing, the viscosity of the motor is set to the maximum value of the motor characteristics shown in FIG. 18A. As a result, the positioning accuracy is prioritized over the compliance, and it is robust against disturbances such as vibration.

(B) Moment of getting off For example, following the support of both legs with the left foot stepping forward, the right leg kicks up the ground with the right rear foot, and the right leg starts to leave the floor. By using own joint angle information, plantar force sensor (or contact sensor), and posture sensor, it is possible to confirm the moment of getting out of bed from its own posture, ground contact state, and motion state (speed / acceleration of each axis). In this state, the airframe (leg, trunk, arm) and the floor form an open link system (see FIG. 24).

  At this time, the actuators of all the joint parts of the left and right legs are set to the intermediate joint characteristics, that is, the servo characteristics of the actuator / motor, as shown in FIG. While increasing the viscosity, the motor viscosity is set to the maximum value of the motor characteristics shown in FIG. 18A. As a result, the support legs can respond at a high speed, and obtain a compliance that is higher than hard characteristics and lower than soft characteristics.

  Also, the left and right shoulder pitches, elbow pitches, and other joint parts have hard joint characteristics, that is, the servo characteristics of the actuator and motor, as shown in FIG. While decreasing, the viscosity of the motor is set to the maximum value of the motor characteristics shown in FIG. 18A. As a result, the positioning accuracy is prioritized over the compliance, and it is robust against disturbances such as vibration.

(C) Single leg support period (when lifting)
Following the removal of the rear leg, the first half of the single leg support period of lifting it is performed. Using the joint angle information, sole force sensor (or contact sensor), and posture sensor, the posture, ground contact state, and motion state (speed / acceleration of each axis), and the transition to the single leg support period Can be confirmed. In this state, the airframe (leg, trunk, arm) and the floor form an open link system (see FIG. 25).

  As shown in FIG. 12, the hard joint characteristics of all joint actuators of the left leg, which is the support leg, that is, the servo characteristics of the actuator and motor are high gain in all bands and the phase advance amount in high bands is reduced. The viscosity of the motor is set to the maximum value of the motor characteristics shown in FIG. 18A. As a result, the positioning accuracy is prioritized and it is robust against disturbances such as vibrations, and the airframe can be supported.

  Also, the thigh roll and thigh pitch of the right leg, which is the free leg, are made to have a hard actuator characteristic, and the lifting operation of the free leg can be executed.

  Further, each joint actuator of the upper limbs such as the left and right shoulder pitches and elbow pitches has soft actuator characteristics, that is, soft joint characteristics, that is, the servo characteristics of the actuator / motor as shown in FIG. In addition to increasing the phase advance amount in the mid-high range, the motor viscosity is set to one third of the maximum value of the motor characteristics shown in FIG. 18B to provide compliance and increase high-speed response to stabilize posture. While enabling the cooperative operation, the position energy and the kinetic energy are easily used during the arm swinging operation.

  In addition, the ankle roll and ankle pitch actuators of the right leg, which is a free leg, also have soft actuator characteristics to prepare for impact when landing.

  In addition, the other joint parts are set to have hard joint characteristics, and positioning accuracy is given priority over compliance, and robustness against disturbances such as vibration is also made.

(D) Single leg support period (when swinging down)
Following the first period of single leg support for lifting the rear leg, the latter part of the single leg support period is performed by swinging the lifted leg forward and swinging it down. Transition to the second half of single-leg support using own joint angle information, plantar force sensor (or contact sensor), posture sensor with own posture, ground contact state and motion state (speed / acceleration of each axis) Can be confirmed. In this state, the airframe (leg, trunk, arm) and the floor form an open link system (see FIG. 26).

  Maintain all the joint actuators of the left leg, which is the support leg, with hard actuator characteristics, and the servo characteristics of the actuator / motor with high gain in all bands and a small phase advance amount in the high band as shown in FIG. The viscosity of the motor is set to the maximum value of the motor characteristics shown in FIG. 18A. As a result, the positioning accuracy is prioritized and it is robust against disturbances such as vibrations, and the airframe can be supported.

  In addition, the thigh roll and thigh pitch of the right leg, which is the free leg, also have a hard actuator characteristic, and the swing-down operation of the free leg can be executed.

  In addition, the joint actuators related to landing such as knee pitch, ankle roll, and ankle pitch of the right leg as a free leg are set to soft actuator characteristics. That is, the soft joint characteristics, that is, the servo characteristics of the actuator / motor, as shown in FIG. 13, the low gain is low and the phase advance amount in the middle / high range is increased, and the motor viscosity is shown in FIG. 18B. Set to one-third of the maximum value of to give compliance and prepare for impact when landing.

  Further, each joint actuator of the upper limbs such as the left and right shoulder pitches and elbow pitches has soft actuator characteristics, that is, soft joint characteristics, that is, the servo characteristics of the actuator / motor as shown in FIG. In addition to increasing the phase advance amount in the mid-high range, the motor viscosity is set to one third of the maximum value of the motor characteristics shown in FIG. 18B to provide compliance and increase high-speed response to stabilize posture. While enabling the cooperative operation, the position energy and the kinetic energy are easily used during the arm swinging operation.

  In addition, the other joint parts are set to have hard joint characteristics, and positioning accuracy is given priority over compliance, and robustness against disturbances such as vibration is also made.

(E) Immediate landing Following support for a single leg, the swinging swinging leg will land on the floor. You can check the moment of landing using your own joint angle information, plantar force sensor (or contact sensor), and posture sensor based on your posture, ground contact and motion (speed / acceleration of each axis). . The lower limb constitutes a closed link system with respect to the floor (see FIG. 27).

  All joint actuators of the left leg, which is the support leg, are maintained in the hard actuator characteristics, and the servo characteristics of the actuator / motor are high in all bands as shown in FIG. The viscosity of the motor is set to the maximum value of the motor characteristics shown in FIG. 18A. As a result, the positioning accuracy is prioritized and it is robust against disturbances such as vibrations, and the airframe can be supported.

  In addition, the thigh roll and thigh pitch of the right leg, which is the free leg, are also set to have a hard actuator characteristic, so that the landing action of the free leg can be executed.

  In addition, the joint actuators related to landing such as knee pitch, ankle roll, and ankle pitch of the right leg as a free leg are set to soft actuator characteristics. That is, the soft joint characteristics, that is, the servo characteristics of the actuator / motor, as shown in FIG. 13, the low gain is low and the phase advance amount in the middle / high range is increased, and the motor viscosity is shown in FIG. 18B. Set to one third of the maximum value of, giving compliance and absorbing impact when landing.

  Further, each joint actuator of the upper limbs such as the left and right shoulder pitches and elbow pitches has soft actuator characteristics, that is, soft joint characteristics, that is, the servo characteristics of the actuator / motor as shown in FIG. In addition to increasing the phase advance amount in the mid-high range, the motor viscosity is set to one third of the maximum value of the motor characteristics shown in FIG. 18B to provide compliance and increase high-speed response to stabilize posture. While enabling the cooperative operation, the position energy and the kinetic energy are easily used during the arm swinging operation.

  In addition, the other joint parts are set to have hard joint characteristics, and positioning accuracy is given priority over compliance, and robustness against disturbances such as vibration is also made.

(F) Support for both legs When the free leg is landed, it returns to the support period for both legs with the left and right legs interchanged. In this state, a closed link system is constituted by the lower limbs and the floor (see FIG. 28). By using own joint angle information, sole force sensor (or contact sensor), and posture sensor, it is possible to confirm both-leg support from its own posture, ground contact state, and motion state (speed / acceleration of each axis).

  At this time, the actuators of all the joint parts of the left and right legs are set to the intermediate joint characteristics, that is, the servo characteristics of the actuator / motor, as shown in FIG. While increasing the viscosity, the motor viscosity is set to the maximum value of the motor characteristics shown in FIG. 18A. As a result, the support legs can respond at a high speed, and obtain a compliance that is higher than hard characteristics and lower than soft characteristics.

  Also, the left and right shoulder pitches, elbow pitches, and other joint parts have hard joint characteristics, that is, the servo characteristics of the actuator and motor, as shown in FIG. While decreasing, the viscosity of the motor is set to the maximum value of the motor characteristics shown in FIG. 18A. As a result, the positioning accuracy is prioritized over the compliance, and it is robust against disturbances such as vibration.

  When the walking motion is continued, the postures (A) to (F) are repeatedly executed.

F. Example of Arrangement of Actuator Characteristic of Each Part of Robot Joint at Stair Ascending / Lowering In this section, a method for controlling the actuator characteristic of each joint part of robot at the time of stair ascending / descending will be described.

  The body of the legged mobile robot is composed of a multi-link structure in which a plurality of joint axes having approximately parallel joint degrees of freedom are connected in the length direction. The link state between the landing site and the floor surface is switched between the open link state and the closed link state.

  In this embodiment, for each stage of the stair climbing operation, according to the switching of the link state, the actuator for driving each joint is appropriately switched to a hard joint characteristic, a soft joint characteristic, and an intermediate joint characteristic, Realizes adaptive tipping action.

F-1. Operation climb stairs First, the arrangement of the controller and the actuator itself characteristics of the actuator at each joint portion when performing an operation of the robot climbing stairs, will be described with reference to FIGS. 29 to 34. In the example shown in each figure, an operation state can be grasped by dividing into 6 stages of A to F.

(A) Both-leg support period In the both-leg support state, the lower limb and the floor form a closed link system (see FIG. 29). By using own joint angle information, sole force sensor (or contact sensor), and posture sensor, it is possible to confirm both-leg support from its own posture, ground contact state, and motion state (speed / acceleration of each axis).

  At this time, the actuators of all the joint parts of the left and right legs are set to the intermediate joint characteristics, that is, the servo characteristics of the actuator / motor, as shown in FIG. While increasing the viscosity, the motor viscosity is set to the maximum value of the motor characteristics shown in FIG. 18A. As a result, the left and right support legs are capable of high-speed response, and obtain a compliance that is higher than hard characteristics and lower than soft characteristics.

  The other joint parts have hard joint characteristics, that is, the servo characteristics of the actuator / motor, as shown in FIG. The maximum value of the motor characteristic shown in FIG. 18A is set. As a result, the positioning accuracy is prioritized over the compliance, and it is robust against disturbances such as vibration.

(B) The moment of getting off For example, following the support of both legs with the right foot stepped up one step, the rear left leg starts getting out of the step from one step below. By using own joint angle information, plantar force sensor (or contact sensor), and posture sensor, it is possible to confirm the moment of getting out of bed from its own posture, ground contact state, and motion state (speed / acceleration of each axis). In this state, the entire airframe moves from the closed link system to the open link system, and the airframe (leg, trunk, and arm) and the floor surface constitute the open link system (see FIG. 30).

  At this time, the actuators of all the joint parts of the left and right legs are set to the intermediate joint characteristics, that is, the servo characteristics of the actuator / motor, as shown in FIG. While increasing the viscosity, the motor viscosity is set to the maximum value of the motor characteristics shown in FIG. 18A. As a result, the left and right support legs are capable of high-speed response, and obtain a compliance that is higher than hard characteristics and lower than soft characteristics.

  The other joint parts have hard joint characteristics, that is, the servo characteristics of the actuator / motor, as shown in FIG. The maximum value of the motor characteristic shown in FIG. 18A is set. As a result, the positioning accuracy is prioritized over the compliance, and it is robust against disturbances such as vibration.

(C) Single leg support period (when lifting)
Following the flooring of the rear left leg, the first half of the single leg support period is lifted. Using the joint angle information, sole force sensor (or contact sensor), and posture sensor, the posture, ground contact state, and motion state (speed / acceleration of each axis), and the transition to the single leg support period Can be confirmed. In this state, the airframe (leg, trunk, arm) and the floor form an open link system (see FIG. 31).

  As shown in FIG. 12, all the joint actuators of the right leg that is the support leg and the thigh roll of the left leg that is the free leg are hard actuator characteristics, that is, the servo characteristics of the actuator motor are high gain and high in all bands. The phase advance amount in the region is reduced, and the viscosity of the motor is set to the maximum value of the motor characteristics shown in FIG. 18A. As a result, the positioning accuracy is prioritized and it is robust against disturbances such as vibrations, and the airframe can be supported.

  Further, the thigh pitch and knee pitch of the left leg, which is the free leg, are maintained at intermediate actuator characteristics, and the free leg lifting operation can be executed.

  In addition, each of the left leg ankle roll and ankle pitch actuator, which is a free leg, has soft actuator characteristics, that is, the servo characteristics of the actuator motor, as shown in FIG. While increasing the amount, the viscosity of the motor is set to one third of the maximum value of the motor characteristics shown in FIG. 18B to provide compliance and increase high-speed response to prepare for impact at landing.

  In addition, the other joint parts are set to have hard joint characteristics, and positioning accuracy is given priority over compliance, and robustness against disturbances such as vibration is also made.

(D) Single leg support period (when swinging down)
Following the first half of the single leg support that lifts the rear left leg, the second leg operation of the single leg support stage is performed in which the lifted left foot is swung out and lowered one step further. Transition to the second half of single-leg support using own joint angle information, plantar force sensor (or contact sensor), posture sensor with own posture, ground contact state and motion state (speed / acceleration of each axis) Can be confirmed. In this state, the open link system is composed of the aircraft (legs, trunk, arms) and the floor, and the fuselage (legs, trunk, arms) and the floor (Fig. 32).

  All joint actuators of the right leg that is the support leg and the thigh roll of the left leg that is the free leg are hard actuator characteristics, that is, the servo characteristics of the actuator motor are high gain and medium high in all bands as shown in FIG. The phase advance amount in the region is small, and the viscosity of the motor is maintained at the maximum value of the motor characteristics shown in FIG. 18A. As a result, the positioning accuracy is prioritized and it is robust against disturbances such as vibrations, and the airframe can be supported.

  Further, the thigh pitch of the left leg as a free leg is maintained at an intermediate actuator characteristic, and the swing-down operation of the free leg can be executed.

  Further, the actuators of the knee leg, ankle roll, and ankle pitch of the left leg, which is a free leg, have soft actuator characteristics, that is, the servo characteristics of the actuator / motor, as shown in FIG. In addition to increasing the amount of phase advance in the motor, the motor viscosity is set to one third of the maximum value of the motor characteristics shown in FIG. 18B to provide compliance and increase high-speed response to prepare for impact at landing. .

  In addition, the other joint parts are set to have hard joint characteristics, and positioning accuracy is given priority over compliance, and robustness against disturbances such as vibration is also made.

(E) Immediate landing Following the support of a single leg, the swinging-down free leg lands on the upper floor. You can check the moment of landing using your own joint angle information, plantar force sensor (or contact sensor), and posture sensor based on your posture, ground contact and motion (speed / acceleration of each axis). . The lower limb constitutes a closed link system with respect to the floor (see FIG. 33).

  As shown in FIG. 12, all the joint actuators of the right leg as the support leg have hard actuator characteristics, that is, the servo characteristics of the actuator and motor. As shown in FIG. The viscosity is maintained at the maximum value of the motor characteristics shown in FIG. 18A. As a result, the positioning accuracy is prioritized and it is robust against disturbances such as vibrations, and the airframe can be supported.

  Further, the thigh roll and thigh pitch of the left leg, which is the free leg, are maintained at intermediate actuator characteristics, and the swing-down operation of the free leg can be executed.

  Further, the actuators of the knee leg, ankle roll, and ankle pitch of the left leg, which is a free leg, have soft actuator characteristics, that is, the servo characteristics of the actuator / motor, as shown in FIG. The phase advance amount is increased, the motor viscosity is maintained at one-third of the maximum value of the motor characteristics shown in FIG. 18B, compliance is given, high-speed response is increased, and impact during landing is absorbed.

  In addition, the other joint parts are set to have hard joint characteristics, and positioning accuracy is given priority over compliance, and robustness against disturbances such as vibration is also made.

(F) Support for both legs When the free leg is landed, it returns to the support period for both legs with the left and right legs interchanged. In this state, a closed link system is configured by the lower limbs and the floor (see FIG. 34). By using own joint angle information, sole force sensor (or contact sensor), and posture sensor, it is possible to confirm both-leg support from its own posture, ground contact state, and motion state (speed / acceleration of each axis).

  At this time, the actuators of all the joint parts of the left and right legs are set to the intermediate joint characteristics, that is, the servo characteristics of the actuator / motor, as shown in FIG. While increasing the viscosity, the motor viscosity is set to the maximum value of the motor characteristics shown in FIG. 18A. As a result, the support leg can respond at high speed and obtain compliance. In addition, the viscosity of the motor increases.

  The other joint parts have hard joint characteristics, that is, the servo characteristics of the actuator / motor, as shown in FIG. The maximum value of the motor characteristic shown in FIG. 18A is set. As a result, the positioning accuracy is prioritized over the compliance, and it is robust against disturbances such as vibration.

  When continuing the operation of ascending the stairs, the postures (A) to (F) are repeatedly executed.

  FIG. 35 shows a processing procedure for switching the actuator characteristics of each joint part of the robot when going up the stairs in the form of a flowchart.

  First, with respect to the actuators of all joint parts constituting the airframe, the low gain as shown in FIG. 12 is increased, the phase advance amount is reduced in the high frequency region, and the joint viscosity is shown as shown in FIG. 18A. Setting is made to increase the resistance (step S21).

  Next, an operation of lifting one leg is executed (step S22).

  Here, when the floor reaction force received at the sole of the leg to be lifted becomes zero (step S23), the support leg performs an operation of supporting the free leg (step S24).

  On the free leg side, the low-frequency gain is small and the phase advance amount in the mid-high frequency is large, as shown in FIG. 13, for the knee joint pitch axis and the ankle roll axis and pitch axis actuators on the free leg side. At the same time, as shown in FIG. 18B, a setting is made to reduce the viscous resistance of the joint (step S25).

  Next, an operation of advancing the free leg to the floor of the stairs one step above is executed (step S26), and further, the landing operation is executed (step S27).

  Here, when the value and direction of the floor reaction force detected at the sole of the foot are in the vicinity of the value of the both-leg support period (step S28), the landing operation of the free leg is completed (step S29). Then, with respect to the knee joint pitch axis on the free leg side and the actuators of the ankle roll axis and the pitch axis, as shown in FIG. 12, the low-frequency gain is increased and the phase advance amount is decreased in the high-frequency region. As shown in 18A, a setting is made to increase the viscous resistance of the joint (step S30).

  When the operation of climbing the stairs is continued as it is (step S31), the free leg is switched to the support leg, the support leg is switched to the free leg (step S32), the process returns to step S22, and the same processing as described above is repeatedly executed.

  On the other hand, when the operation of ascending the stairs is completed (step S31), the foot that was the support leg becomes a free leg and is advanced to the stepped floor surface (step S33). At this time, for each of the leg ankle roll axis and pitch axis actuators that were free legs, as shown in FIG. 12, the low-frequency gain is increased, the phase advance amount is decreased in the high-frequency region, and FIG. As shown, the joint is set to increase the viscous resistance. And the leg which was a free leg turns into a support leg, and the operation | movement which supports a free leg is performed.

  Next, the landing operation of the free leg is executed (step S34). At this time, the support leg performs an operation of instructing the free leg.

  Next, when the value and direction of the floor reaction force detected at the sole of the free leg is close to the value of the both-leg support period (step S35), the landing operation of the free leg is completed (step S36). At this time, for each of the knee joint pitch axis and the ankle roll axis and the pitch axis actuator on the free leg side, as shown in FIG. 12, the low-frequency gain is increased, and the phase advance amount is decreased in the high-frequency region, As shown in FIG. 18A, setting is made to increase the viscous resistance of the joint. As a result, both legs are aligned, both legs are supported, and the stairs climbing operation can be completed.

F-2. And operating subsequently down the stairs, the robot the arrangement characteristics of the controller and the actuator itself actuator has at each joint portion when descending the stairs will be described with reference to FIGS. 36 41. In the example shown in each figure, an operation state can be grasped by dividing into 6 stages of A to F.

(A) Both-leg support period In the both-leg support state, the lower limb and the floor form a closed link system (see FIG. 36). By using own joint angle information, sole force sensor (or contact sensor), and posture sensor, it is possible to confirm both-leg support from its own posture, ground contact state, and motion state (speed / acceleration of each axis).

  At this time, the actuators of all the joint parts of the left and right legs are set to the intermediate joint characteristics, that is, the servo characteristics of the actuator / motor, as shown in FIG. While increasing the viscosity, the motor viscosity is set to the maximum value of the motor characteristics shown in FIG. 18A. As a result, the left and right support legs are capable of high-speed response, and obtain a compliance that is higher than hard characteristics and lower than soft characteristics.

  The other joint parts have hard joint characteristics, that is, the servo characteristics of the actuator / motor, as shown in FIG. The maximum value of the motor characteristic shown in FIG. 18A is set. As a result, the positioning accuracy is prioritized over the compliance, and it is robust against disturbances such as vibration.

(B) The moment of getting off For example, following the support of both legs with the left foot stepped down one step, the right rear leg starts to leave the step from the top. By using own joint angle information, plantar force sensor (or contact sensor), and posture sensor, it is possible to confirm the moment of getting out of bed from its own posture, ground contact state, and motion state (speed / acceleration of each axis). In this state, the entire airframe shifts from the closed link system to the open link system, and the airframe (leg, trunk, arm) and the floor surface constitute the open link system (see FIG. 37).

  At this time, the actuators of all the joint parts of the left and right legs are set to the intermediate joint characteristics, that is, the servo characteristics of the actuator / motor, as shown in FIG. While increasing the viscosity, the motor viscosity is set to the maximum value of the motor characteristics shown in FIG. 18A. As a result, the left and right support legs are capable of high-speed response, and obtain a compliance that is higher than hard characteristics and lower than soft characteristics.

  The other joint parts have hard joint characteristics, that is, the servo characteristics of the actuator / motor, as shown in FIG. The maximum value of the motor characteristic shown in FIG. 18A is set. As a result, the positioning accuracy is prioritized over the compliance, and it is robust against disturbances such as vibration.

(C) Single leg support period (when lifting)
Following the flooring of the right rear leg, the first half of the single leg support period is lifted. Using the joint angle information, sole force sensor (or contact sensor), and posture sensor, the posture, ground contact state, and motion state (speed / acceleration of each axis), and the transition to the single leg support period Can be confirmed. In this state, the airframe (legs, trunk, arms) and the floor form an open link system (see FIG. 38).

  As shown in FIG. 12, the hard joint characteristics of all joint actuators of the left leg, which is the support leg, that is, the servo characteristics of the actuator and motor are high gain in all bands and the phase advance amount in high bands is reduced. The viscosity of the motor is set to the maximum value of the motor characteristics shown in FIG. 18A. As a result, the positioning accuracy is prioritized and it is robust against disturbances such as vibrations, and the airframe can be supported.

  Also, the thigh roll and thigh pitch of the right leg, which is the free leg, are made to have a hard actuator characteristic, and the lifting operation of the free leg can be executed. In addition, the knee pitch of the right leg is maintained at an intermediate actuator characteristic.

  In addition, each of the ankle roll and ankle pitch actuators of the right leg, which is a free leg, has soft actuator characteristics, that is, the servo characteristics of the actuator motor, as shown in FIG. While increasing the amount, the viscosity of the motor is set to one third of the maximum value of the motor characteristics shown in FIG. 18B to provide compliance and increase high-speed response to prepare for impact at landing.

  In addition, the other joint parts are set to have hard joint characteristics, and positioning accuracy is given priority over compliance, and robustness against disturbances such as vibration is also made.

(D) Single leg support period (when swinging down)
Following the first half of the single leg support for lifting the rear right leg, the latter half of the single leg support stage is performed in which the right leg is further lowered. Transition to the second half of single-leg support using own joint angle information, plantar force sensor (or contact sensor), posture sensor with own posture, ground contact state and motion state (speed / acceleration of each axis) Can be confirmed. In this state, the airframe (leg, trunk, arm) and the floor form an open link system (see FIG. 39).

  As shown in FIG. 12, all the joint actuators of the left leg, which is the support leg, have hard actuator characteristics, that is, the servo characteristics of the actuator and the motor, as shown in FIG. The viscosity is maintained at the maximum value of the motor characteristics shown in FIG. 18A. As a result, the positioning accuracy is prioritized and it is robust against disturbances such as vibrations, and the airframe can be supported.

  In addition, the thigh roll and thigh pitch of the right leg, which is the free leg, also have a hard actuator characteristic, and the swing-down operation of the free leg can be executed.

  Further, the knee pitch, ankle roll, and ankle pitch actuators of the right leg, which is a free leg, have soft actuator characteristics, that is, the servo characteristics of the actuator motor are low in the low range and low in gain as shown in FIG. In addition to increasing the amount of phase advance in the motor, the motor viscosity is set to one third of the maximum value of the motor characteristics shown in FIG. 18B to provide compliance and increase high-speed response to prepare for impact at landing. .

  In addition, the other joint parts are set to have hard joint characteristics, and positioning accuracy is given priority over compliance, and robustness against disturbances such as vibration is also made.

(E) Immediate landing Following support for a single leg, the swinging swinging leg will land on the floor surface one step below. You can check the moment of landing using your own joint angle information, plantar force sensor (or contact sensor), and posture sensor based on your posture, ground contact and motion (speed / acceleration of each axis). . The lower limb constitutes a closed link system with respect to the floor surface (see FIG. 40).

  As shown in FIG. 12, all the joint actuators of the left leg, which is the support leg, have hard actuator characteristics, that is, the servo characteristics of the actuator and the motor, as shown in FIG. The viscosity is maintained at the maximum value of the motor characteristics shown in FIG. 18A. As a result, the positioning accuracy is prioritized and it is robust against disturbances such as vibrations, and the airframe can be supported.

  In addition, the thigh roll and thigh pitch of the right leg, which is the free leg, are also set to have a hard actuator characteristic, so that the landing action of the free leg can be executed.

  Further, the knee pitch, ankle roll, and ankle pitch actuators of the right leg, which is a free leg, have soft actuator characteristics, that is, the servo characteristics of the actuator motor are low in the low range and low in gain as shown in FIG. The phase advance amount is increased, the motor viscosity is maintained at one-third of the maximum value of the motor characteristics shown in FIG. 18B, compliance is given, high-speed response is increased, and impact during landing is absorbed.

  In addition, the other joint parts are set to have hard joint characteristics, and positioning accuracy is given priority over compliance, and robustness against disturbances such as vibration is also made.

(F) Support for both legs When the free leg is landed, it returns to the support period for both legs with the left and right legs interchanged. In this state, a closed link system is configured by the lower limbs and the floor (see FIG. 41). By using own joint angle information, sole force sensor (or contact sensor), and posture sensor, it is possible to confirm both-leg support from its own posture, ground contact state, and motion state (speed / acceleration of each axis).

  At this time, the actuators of all the joint parts of the left and right legs are set to the intermediate joint characteristics, that is, the servo characteristics of the actuator / motor, as shown in FIG. While increasing the viscosity, the motor viscosity is set to the maximum value of the motor characteristics shown in FIG. 18A. As a result, the support legs can respond at a high speed, and obtain a compliance that is higher than hard characteristics and lower than soft characteristics.

  The other joint parts have hard joint characteristics, that is, the servo characteristics of the actuator / motor, as shown in FIG. The maximum value of the motor characteristic shown in FIG. 18A is set. As a result, the positioning accuracy is prioritized over the compliance, and it is robust against disturbances such as vibration.

  When continuing the operation of going down the stairs, the postures (A) to (F) are repeatedly executed.

  FIG. 42 shows a processing procedure for switching the actuator characteristics of each joint part of the robot when climbing the stairs in the form of a flowchart.

  First, with respect to the actuators of all joint parts constituting the airframe, the low gain as shown in FIG. 12 is increased, the phase advance amount is reduced in the high frequency region, and the joint viscosity is shown as shown in FIG. 18A. Setting to increase the resistance is performed (step S41).

  Next, an operation of lifting one leg is executed (step S42).

  Here, when the floor reaction force received at the sole of the leg to be lifted becomes zero (step S43), the support leg performs an operation of supporting the free leg (step S44).

  On the free leg side, the low-frequency gain is small and the phase advance amount is large in the mid-high range, as shown in FIG. 13, for the knee joint pitch axis and the ankle roll axis and pitch axis actuators on the free leg side. At the same time, as shown in FIG. 18B, a setting is made to reduce the viscous resistance of the joint (step S45).

  Next, an operation of advancing the swing leg to the floor of the stairs one step below is executed (step S46), and further, the landing operation is executed (step S47).

  Here, when the value and direction of the floor reaction force detected at the sole becomes close to the value of the both-leg support period (step S48), the landing operation of the free leg is completed (step S49). Then, with respect to the knee joint pitch axis on the free leg side and the actuators of the ankle roll axis and the pitch axis, as shown in FIG. 12, the low-frequency gain is increased and the phase advance amount is decreased in the high-frequency region. As shown in 18A, a setting is made to increase the viscous resistance of the joint (step S50).

  When the operation of going down the stairs is continued as it is (step S51), the free leg is switched to the support leg, the support leg is switched to the free leg (step S52), the process returns to step S42, and the same processing as described above is repeatedly executed.

  On the other hand, when the operation of descending the stairs is completed (step S51), the foot that was the support leg becomes a free leg and is advanced to the upper stair floor (step S53). At this time, for each of the leg ankle roll axis and pitch axis actuators that were free legs, as shown in FIG. 12, the low-frequency gain is increased, the phase advance amount is decreased in the high-frequency region, and FIG. As shown, the joint is set to increase the viscous resistance. And the leg which was a free leg turns into a support leg, and the operation | movement which supports a free leg is performed.

  Next, the landing operation of the free leg is executed (step S54). At this time, the support leg performs an operation of instructing the free leg.

  Next, when the value and direction of the floor reaction force detected at the sole of the free leg is close to the value of the both-leg support period (step S55), the landing operation of the free leg is completed (step S56). At this time, for the knee joint pitch axis on the free leg side and the actuators of the ankle roll axis and the pitch axis, as shown in FIG. 12, the low-frequency gain is increased and the phase advance amount is decreased in the high-frequency region, As shown in FIG. 18A, setting is made to increase the viscous resistance of the joint. As a result, both legs are aligned and both legs are supported, and the stairs descending operation can be completed.

G. Example of Arrangement of Actuator Characteristics of Each Joint Part of Robot During Turning In this section, a method for controlling the actuator characteristics of each joint part of the robot during turning of the airframe will be described.

  The body of the legged mobile robot is composed of a multi-link structure in which a plurality of joint axes having approximately parallel joint degrees of freedom are connected in the length direction. The link state between the landing site and the floor surface is switched between the open link state and the closed link state.

  In this embodiment, the actuator for driving each joint is appropriately switched to a hard joint characteristic, a soft joint characteristic, and an intermediate joint characteristic in accordance with the switching of the link state at each stage of the turning motion of the aircraft. Realize adaptive tipping motion.

  Here, the arrangement of the characteristics of the controller and the actuator of the actuator in each joint part of the robot when the machine turns will be described with reference to FIG.

  When the aircraft turns, neck pitch axis, shoulder pitch axis, elbow pitch axis, trunk roll axis, trunk pitch axis, trunk yaw axis, hip roll and pitch axis, and knee pitch axis on the support leg side High positioning accuracy is required at each joint portion of the ankle roll and the pitch axis.

  Accordingly, in the actuators at these joint sites, the proportional gain of the servo controller is increased to increase the gain of the entire system so that the gain can be obtained up to the low frequency band. As shown in FIG. 12, the frequency characteristic is such that the amount of phase advance is reduced at a high frequency, so that stability is ensured although it does not contribute much to high-speed response. Further, as shown in FIG. 18A, the viscous resistance of the motor is increased so as to be robust against disturbances such as vibration.

  On the other hand, at the time of turning of the airframe, high speed responsiveness and compliance are important in each joint part of the knee pitch axis, the ankle roll and the pitch axis on the free leg side.

  Therefore, by reducing the proportional gain and reducing the gain of the entire system in the actuators at these joint sites, the gain in the low frequency band is reduced, and mechanical passivity (compliance) is easily obtained. Further, as shown in FIG. 13, the frequency characteristic (phase compensation characteristic) is set so that the phase advance amount becomes large in the middle and high range so as to obtain high-speed response. In addition, as shown in FIG. 18B, the viscous resistance of the motor is reduced to facilitate obtaining mechanical passivity (compliance).

  By applying the characteristics of the actuator controller as shown in FIG. 13 and the characteristics of the actuator itself to the free leg, mechanical passivity (compliance) can be obtained for the arms and legs. Accordingly, it becomes easy to use the potential energy when the leg is swung up during the turning operation as energy for assisting the operation in the next operation of swinging down. As a result, energy consumption is reduced, and the consumption of the battery as the power source for driving the body is also reduced.

  Subsequently, the arrangement of the characteristics of the controller and the actuator itself of the actuator in each joint part when the robot performs a turning motion will be described with reference to FIGS. 44 to 51. In the example shown in each figure, an operation state can be grasped in eight stages A to H.

(A) Both-leg support period In the both-leg support state, the lower limb and the floor form a closed link system (see FIG. 44). By using own joint angle information, sole force sensor (or contact sensor), and posture sensor, it is possible to confirm both-leg support from its own posture, ground contact state, and motion state (speed / acceleration of each axis).

  At this time, the actuators of all the joint parts of the left and right legs are set to the intermediate joint characteristics, that is, the servo characteristics of the actuator / motor, as shown in FIG. While increasing the viscosity, the motor viscosity is set to the maximum value of the motor characteristics shown in FIG. 18A. As a result, the left and right support legs are capable of high-speed response, and obtain a compliance that is higher than hard characteristics and lower than soft characteristics.

  The other joint parts have hard joint characteristics, that is, the servo characteristics of the actuator / motor, as shown in FIG. The maximum value of the motor characteristic shown in FIG. 18A is set. As a result, the positioning accuracy is prioritized over the compliance, and it is robust against disturbances such as vibration.

(B) Single leg support period (when lifting)
Perform the first half of the single leg support period by lifting the right leg. Using the joint angle information, sole force sensor (or contact sensor), and posture sensor, the posture, ground contact state, and motion state (speed / acceleration of each axis), and the transition to the single leg support period Can be confirmed. In this state, the airframe (leg, trunk, and arm) and the floor form an open link system (see FIG. 45).

  As shown in FIG. 12, all the joint actuators of the left leg, which is the support leg, have hard actuator characteristics, that is, the servo characteristics of the actuator and the motor, as shown in FIG. The viscosity is set to the maximum value of the motor characteristic shown in FIG. 18A. As a result, the left leg as the support leg gives priority to positioning accuracy, and is robust against disturbances such as vibration, and can support the aircraft as a rotating shaft during turning.

  In addition, the right leg thigh yaw, thigh roll, and thigh pitch, which are free legs, are also set to have a hard actuator characteristic so that the lifting action of the free leg can be executed.

In addition, each of the ankle roll and ankle pitch actuators of the right leg, which is a free leg, has soft actuator characteristics, that is, the servo characteristics of the actuator motor, as shown in FIG. While increasing the amount, the motor viscosity is set to one third of the maximum value of the motor characteristics shown in FIG. 18B to give compliance, and to obtain compliance that is higher than hard characteristics and lower than soft characteristics.

  In addition, the other joint parts are set to have hard joint characteristics, and positioning accuracy is given priority over compliance, and robustness against disturbances such as vibration is also made.

(C) Single leg support period Following the first period of the single leg support in which the right leg is lifted, an operation in the latter half of the single leg support period is performed in which the lifted right leg is turned with the left leg, which is the support leg, as the rotation axis. Transition to the second half of single-leg support using own joint angle information, plantar force sensor (or contact sensor), posture sensor with own posture, ground contact state and motion state (speed / acceleration of each axis) Can be confirmed. In this state, the airframe (leg, trunk, arm) and the floor form an open link system (see FIG. 46).

  As shown in FIG. 12, all the joint actuators of the left leg, which is the support leg, have hard actuator characteristics, that is, the servo characteristics of the actuator and the motor, as shown in FIG. The viscosity is maintained at the maximum value of the motor characteristics shown in FIG. 18A. As a result, priority is given to the positioning accuracy of the left leg as the rotation axis during turning, and it is robust against disturbances such as vibrations, and the airframe can be supported.

  Also, the right leg thigh yaw, thigh roll, and thigh pitch, which are free legs, are set to have a hard actuator characteristic, and the swing movement of the free leg with the left leg as the rotation axis can be executed.

  Further, the knee pitch, ankle roll and ankle pitch actuators of the right leg, which is a free leg, have soft actuator characteristics, that is, the servo characteristics of the actuator motor are low in the low range and low in gain as shown in FIG. In addition to increasing the phase advance amount at, the motor viscosity is set to one third of the maximum value of the motor characteristics shown in FIG.

  In addition, the other joint parts are set to have hard joint characteristics, and positioning accuracy is given priority over compliance, and robustness against disturbances such as vibration is also made.

(D) Supporting both legs When the right leg as the free leg is landed after the turning motion is finished, the left and right legs are interchanged, and the both leg support period is resumed. In this state, a closed link system is configured by the lower limbs and the floor (see FIG. 47). By using own joint angle information, sole force sensor (or contact sensor), and posture sensor, it is possible to confirm both-leg support from its own posture, ground contact state, and motion state (speed / acceleration of each axis).

  At this time, the actuators of all the joint parts of the left and right legs are set to the intermediate joint characteristics, that is, the servo characteristics of the actuator / motor, as shown in FIG. While increasing the viscosity, the motor viscosity is set to the maximum value of the motor characteristics shown in FIG. 18A. As a result, the left and right support legs are capable of high-speed response, and obtain a compliance that is higher than hard characteristics and lower than soft characteristics.

  The other joint parts have hard joint characteristics, that is, the servo characteristics of the actuator / motor, as shown in FIG. The maximum value of the motor characteristic shown in FIG. 18A is set. As a result, the positioning accuracy is prioritized over the compliance, and it is robust against disturbances such as vibration.

(E) Single leg support period (when lifting)
This time, the first half of the single leg support period is performed by lifting the left leg. Using the joint angle information, sole force sensor (or contact sensor), and posture sensor, the posture, ground contact state, and motion state (speed / acceleration of each axis), and the transition to the single leg support period Can be confirmed. In this state, the airframe (legs, trunk, arms) and the floor form an open link system (see FIG. 48).

  As shown in FIG. 12, all the joint actuators of the right leg, which is the support leg, have hard actuator characteristics, that is, the servo characteristics of the actuator and the motor, as shown in FIG. The viscosity is set to the maximum value of the motor characteristic shown in FIG. 18A. As a result, the right leg as the support leg gives priority to positioning accuracy, is robust against disturbances such as vibration, and can support the airframe as a rotating shaft during turning.

  In addition, the left leg thigh yaw, thigh roll and thigh pitch, which are free legs, are also set to have a hard actuator characteristic so that the free leg can be lifted.

Further, the soft actuator characteristics of each actuator of the left leg ankle roll and ankle pitch is free leg, i.e., the phase in the low gain and high and high band servo characteristics of the actuator motor in the low range, as shown in FIG. 13 While increasing the advance amount, the viscosity of the motor is set to one third of the maximum value of the motor characteristics shown in FIG. 18B to give compliance and increase high-speed response to adapt to the turning motion around the right leg. .

  In addition, the other joint parts are set to have hard joint characteristics, and positioning accuracy is given priority over compliance, and robustness against disturbances such as vibration is also made.

(F) Single leg support period Following the first period of single leg support in which the left leg is lifted, the lifted left leg is turned with the right leg, which is the support leg, as the rotation axis. Transition to the second half of single-leg support using own joint angle information, plantar force sensor (or contact sensor), posture sensor with own posture, ground contact state and motion state (speed / acceleration of each axis) Can be confirmed. In this state, the airframe (leg, trunk, arm) and the floor form an open link system (see FIG. 49).

  As shown in FIG. 12, all the joint actuators of the right leg as the support leg have hard actuator characteristics, that is, the servo characteristics of the actuator and motor. As shown in FIG. The viscosity is maintained at the maximum value of the motor characteristics shown in FIG. 18A. As a result, priority is given to the positioning accuracy of the right leg as the rotation axis during turning, and it is robust against disturbances such as vibrations, and the airframe can be supported.

  Further, the left leg thigh yaw, thigh roll and thigh pitch, which are free legs, are also set to have a hard actuator characteristic so that the swing movement of the free leg with the right leg as the rotation axis can be executed.

  In addition, each of the left leg ankle roll and ankle pitch actuator, which is a free leg, has soft actuator characteristics, that is, the servo characteristics of the actuator motor, as shown in FIG. While increasing the amount, the motor viscosity is set to one third of the maximum value of the motor characteristics shown in FIG. 18B to give compliance, and to obtain compliance that is higher than hard characteristics and lower than soft characteristics.

  In addition, the other joint parts are set to have hard joint characteristics, and positioning accuracy is given priority over compliance, and robustness against disturbances such as vibration is also made.

(G) Single leg support period The operation of turning the left leg lifted with the right leg, which is the support leg as the rotation axis, is continued to perform the latter half of the single leg support period. Transition to the second half of single-leg support using own joint angle information, plantar force sensor (or contact sensor), posture sensor with own posture, ground contact state and motion state (speed / acceleration of each axis) Can be confirmed. In this state, the airframe (legs, trunk, arms) and the floor form an open link system (see FIG. 50).

  As shown in FIG. 12, all the joint actuators of the right leg as the support leg have hard actuator characteristics, that is, the servo characteristics of the actuator and motor. As shown in FIG. The viscosity is maintained at the maximum value of the motor characteristics shown in FIG. 18A. As a result, priority is given to the positioning accuracy of the right leg as the rotation axis during turning, and it is robust against disturbances such as vibrations, and the airframe can be supported.

  In addition, the left leg thigh yaw, thigh roll and thigh pitch, which are free legs, are also set to have a hard actuator characteristic so that the swing movement of the free leg with the right leg as the rotation axis can be continued.

  In addition, the left leg ankle roll and ankle pitch actuators, which have soft actuator characteristics, that is, the servo characteristics of the actuator / motor, as shown in FIG. While increasing the amount, the viscosity of the motor is set to one-third of the maximum value of the motor characteristics shown in FIG.

  In addition, the other joint parts are set to have hard joint characteristics, and positioning accuracy is given priority over compliance, and robustness against disturbances such as vibration is also made.

(H) Support for both legs When the swinging motion is finished and the right leg as a free leg is landed, the both leg support period is resumed. In this state, a closed link system is configured by the lower limbs and the floor (see FIG. 51). By using own joint angle information, sole force sensor (or contact sensor), and posture sensor, it is possible to confirm both-leg support from its own posture, ground contact state, and motion state (speed / acceleration of each axis).

  At this time, the actuators of all the joint parts of the left and right legs are set to the intermediate joint characteristics, that is, the servo characteristics of the actuator / motor, as shown in FIG. While increasing the viscosity, the motor viscosity is set to the maximum value of the motor characteristics shown in FIG. 18A. As a result, the left and right support legs are capable of high-speed response, and obtain a compliance that is higher than hard characteristics and lower than soft characteristics.

  The other joint parts have hard joint characteristics, that is, the servo characteristics of the actuator / motor, as shown in FIG. The maximum value of the motor characteristic shown in FIG. 18A is set. As a result, the positioning accuracy is prioritized over the compliance, and it is robust against disturbances such as vibration.

  FIG. 52 shows a processing procedure for switching the actuator characteristics of each joint portion of the robot when the airframe turns in the form of a flowchart.

  First, as shown in FIG. 12, the low-frequency gain is large, the phase advance amount is small in the high-frequency region, and the joint viscous resistance as shown in FIG. Set to increase. (Step S61).

  Next, an operation of lifting one leg is executed (step S62).

  Here, when the floor reaction force received at the sole of the leg to be lifted becomes zero (step S63), the support leg supports the free leg and performs the turning motion of the body (step S64).

  On the free leg side, as shown in FIG. 13, with respect to the knee joint pitch axis and the ankle roll axis and pitch axis actuators on the free leg side, the low gain is reduced and the phase advance amount is increased in the middle and high ranges. In addition, as shown in FIG. 18B, a setting is made to reduce the viscous resistance of the joint (step S65).

  Next, a swing operation as a free leg is executed (step S66), and the landing operation is further executed (step S67).

  Here, when the value of the floor reaction force detected by the sole becomes close to the value of the both-leg support period (step S68), the landing operation of the free leg is completed (step S69).

  Then, for the knee joint pitch axis on the free leg side and the actuators of the ankle roll axis and the pitch axis, as shown in FIG. 12, the low gain is increased, the phase advance amount is decreased in the high frequency range, and As shown in 18A, a setting is made to increase the viscous resistance of the joint (step S70).

  When the turning operation is continued as it is (step S71), the free leg is switched to the support leg and the support leg is switched to the free leg (step S72), the process returns to step S62, and the same processing as described above is repeatedly executed.

  On the other hand, when the turning operation is finished (step S71), the entire processing routine is finished.

  The present invention has been described in detail above with reference to specific embodiments. However, it is obvious that those skilled in the art can make modifications and substitutions of the embodiments without departing from the gist of the present invention.

  The gist of the present invention is not necessarily limited to a product called a “robot”. That is, as long as it is a mechanical device that performs an exercise resembling human movement using an electrical or magnetic action, the present invention can be applied to products belonging to other industrial fields such as toys. Can be applied.

  In the present specification, the description has been made centering on the motor / actuator as the actuator for driving the joint of the robot, but the gist of the present invention is not limited to this. In addition to motors and actuators that have a rotation axis that directly drives the joint angle, servo gain control is also applied to actuators that drive joints by expanding and contracting the distance of links that connect joints like muscles. In addition, the effects of the present invention can be suitably achieved by controlling the viscosity. Examples of the latter joint drive actuator include a shape memory alloy actuator, a fluid actuator, and a polymer actuator.

  Further, in this specification, a circuit example configured by using a switching element made of a bipolar transistor for switching control of a coil current to a coil of a motor / actuator has been described. However, a MOS-FET or other semiconductor element is used. Those skilled in the art will appreciate that this type of control circuit can be implemented using.

  In short, the present invention has been disclosed in the form of exemplification, and the description of the present specification should not be interpreted in a limited manner. In order to determine the gist of the present invention, the claims section described at the beginning should be considered.

FIG. 1 is a view showing a state in which a legged mobile robot used for carrying out the present invention is viewed from the front. FIG. 2 is a view showing a state in which a legged mobile robot used for carrying out the present invention is viewed from the rear. FIG. 3 is a diagram schematically illustrating a joint degree-of-freedom configuration included in the legged mobile robot. FIG. 4 is a diagram schematically showing a control system configuration of the legged mobile robot 100. FIG. 5 is a diagram showing the configuration of the servo controller of the actuator. FIG. 6 is a diagram showing the frequency characteristics of the transfer function expression model gain and phase of the motor and the speed reducer shown in FIG. FIG. 7 is a diagram for explaining an example in which a phase compensation band is arbitrarily selected as a design example of phase compensation control in the servo controller shown in FIG. FIG. 8 is a diagram for explaining an example in which the amount of phase compensation is arbitrarily selected as a design example of the phase compensation control in the servo controller shown in FIG. FIG. 9 is a diagram for explaining a design example of a controller that changes the magnitude of the series compensation gain indicated by K in the servo controller shown in FIG. FIG. 10 is a diagram showing open loop characteristics when the servo controller of the actuator is mounted so as to arbitrarily select the frequency band with a constant phase compensation amount as shown in FIG. FIG. 11 is a diagram showing a state in which control of the series compensation gain is further adopted in Example C (s) -3 in which the phase lead compensation is performed only in the high frequency region shown in FIG. FIG. 12 is a diagram showing an example in which the gain is set to be high as a whole with respect to the open loop characteristic of the actuator position control system, and the characteristic is set so as to reduce the phase advance amount in a high range. 13, with respect to open-loop characteristic of the position control system of the actuator, a view in the low range and low gain, showing an example of setting the characteristic such as to increase the amount of phase lead in the mid-high range. FIG. 14 is a diagram illustrating a configuration example of an equivalent circuit of a current control circuit for supplying a coil current of a DC motor to which a coil current control mechanism is applied. FIG. 15 is a diagram showing a specific circuit configuration of the additional logic circuit. FIG. 16 is a diagram showing the output characteristics of each transistor control signal of the additional logic circuit when the high-level BRAKE_PWM control signal is input, together with the coil current waveform characteristics and the torque output characteristics. FIG. 17 is a diagram showing the output characteristics of each transistor control signal of the additional logic circuit together with the coil current waveform characteristics and torque output characteristics when a BRAKE_PWM control signal having a predetermined duty ratio is input by PWM control. . FIG. 18 is a diagram showing the relationship of control areas in which the viscous resistance of the motor is dynamically controlled by the duty ratio of the BRAKE_PWM control signal. FIG. 19 is a diagram for explaining the arrangement of the characteristics of the actuator controller and the actuator itself at each joint site when the robot performs a walking motion. FIG. 20 is a flowchart showing a processing procedure for switching the actuator characteristics of each joint part when the robot performs a walking motion. FIG. 22 is a diagram illustrating a state in which a closed link system is configured by both legs and the floor surface by supporting both legs in the standing posture. FIG. 22 is a diagram showing a state in which an open link is configured by both legs and the floor surface by supporting a single leg in a standing posture. FIG. 23 is a diagram illustrating a process in which the robot performs a walking motion. FIG. 24 is a diagram illustrating a process in which the robot performs a walking motion. FIG. 25 is a diagram illustrating a process in which the robot performs a walking motion. FIG. 26 is a diagram illustrating a process in which the robot performs a walking motion. FIG. 27 is a diagram illustrating a process in which the robot performs a walking motion. FIG. 28 is a diagram illustrating a process in which the robot performs a walking motion. FIG. 29 is a diagram illustrating a process in which the robot performs an operation of ascending the stairs. FIG. 30 is a diagram illustrating a process in which the robot performs an operation of ascending the stairs. FIG. 31 is a diagram illustrating a process in which the robot performs an operation of ascending the stairs. FIG. 32 is a diagram illustrating a process in which the robot performs an operation of ascending the stairs. FIG. 33 is a diagram illustrating a process in which the robot performs an operation of ascending the stairs. FIG. 34 is a diagram illustrating a process in which the robot performs an operation of ascending the stairs. FIG. 35 is a flowchart showing a processing procedure for switching the actuator characteristics of each joint part of the robot when going up the stairs. FIG. 36 is a diagram illustrating a process in which the robot performs an operation to go down the stairs. FIG. 37 is a diagram illustrating a process in which the robot performs an operation to go down the stairs. FIG. 38 is a diagram illustrating a process in which the robot performs an operation to go down the stairs. FIG. 39 is a diagram illustrating a process in which the robot performs an operation to go down the stairs. FIG. 40 is a diagram illustrating a process in which the robot performs an operation to go down the stairs. FIG. 41 is a diagram illustrating a process in which the robot performs an operation to go down the stairs. FIG. 42 is a flowchart showing a processing procedure for switching the actuator characteristics of each joint portion of the robot when going down the stairs. FIG. 43 is a diagram for explaining the arrangement of the characteristics of the controller and the actuator of the actuator in each joint part of the robot when the airframe turns. FIG. 44 is a diagram illustrating a process in which the robot performs a turning operation. FIG. 45 is a diagram illustrating a process in which the robot performs a turning motion. FIG. 46 is a diagram illustrating a process in which the robot performs a turning motion. FIG. 47 is a diagram illustrating a process in which the robot performs a turning motion. FIG. 48 is a diagram illustrating a process in which the robot performs a turning motion. FIG. 49 is a diagram illustrating a process in which the robot performs a turning motion. FIG. 50 is a diagram illustrating a process in which the robot performs a turning motion. FIG. 51 is a diagram illustrating a process in which the robot performs a turning motion. FIG. 52 is a flowchart showing a processing procedure for switching the actuator characteristics of each joint portion of the robot when the aircraft turns.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Neck joint yaw axis 2A ... 1st neck joint pitch axis 2B ... 2nd neck joint (head) pitch axis 3 ... Neck joint roll axis 4 ... Shoulder joint pitch axis 5 ... Shoulder joint roll axis 6 ... Upper arm yaw axis 7 ... Elbow joint pitch axis 8 ... Wrist joint yaw axis 9 ... Trunk pitch axis 10 ... Trunk roll axis 11 ... Hip joint yaw axis 12 ... Hip joint pitch axis 13 ... Hip joint roll axis 14 ... Knee joint pitch axis 15 ... Ankle joint pitch Axis 16 ... Ankle joint roll axis 30 ... Head unit, 40 ... Trunk unit 50 ... Arm unit, 51 ... Upper arm unit 52 ... Elbow joint unit, 53 ... Forearm unit 60 ... Leg unit, 61 ... Thigh unit 62 ... knee joint unit, 63 ... shin unit 80 ... control unit, 81 ... main control unit 82 ... peripheral circuit 91, 92 ... grounding confirmation sensor 93, 94 ... acceleration sensor 95 ... posture sensor 9 ... acceleration sensor 100 ... legged mobile robot

Claims (17)

In a robot apparatus including at least a torso, an arm, and two or more movable legs and including a plurality of joints,
The movable leg includes at least a thigh, a knee pitch, and an ankle pitch joint, and the arm includes a shoulder and an elbow joint,
The servo controller for the position control system of the actuator that drives each joint has a low gain in the low range and a large phase advance amount in the middle and high range, and a high gain in the entire range and a small phase advance amount in the high range. The actuator motor has a state where the viscous resistance is small and a state where it is large,
The robot apparatus is:
Actuator characteristic control means for combining the gain and phase compensation control of the servo controller of the actuator position control system for driving each joint and the control of the viscous resistance of the actuator motor;
A walking motion control means for controlling the airframe motion during walking using the movable legs,
The actuator characteristic control means is a servo control of an actuator for driving each joint of the support leg when two or more movable legs become support legs during walking to form a closed link system with the support legs and the floor surface. Increase the amount of phase advance in the low range, low gain and mid-high range, and increase the viscous resistance of the actuator and motor to increase the viscous resistance of the joint.
A robot apparatus characterized by that. In a robot apparatus including at least a torso, an arm, and two or more movable legs and including a plurality of joints,
The movable leg includes at least a thigh, a knee pitch, and an ankle pitch joint, and the arm includes a shoulder and an elbow joint,
The servo controller for the position control system of the actuator that drives each joint has a low gain in the low range and a large phase advance amount in the middle and high range, and a high gain in the entire range and a small phase advance amount in the high range. The actuator motor has a state where the viscous resistance is small and a state where it is large,
The robot apparatus is:
Actuator characteristic control means for combining the gain and phase compensation control of the servo controller of the actuator position control system for driving each joint and the control of the viscous resistance of the actuator motor;
A walking motion control means for controlling the airframe motion during walking using the movable legs,
The actuator characteristic control means swings the arm between the two or more supporting legs after leaving the rear leg, lifting the swinging leg forward, swinging it down, and swinging it down on the floor. The servo controller of the actuator that drives each joint of the arm performing low-frequency, low-gain, large phase advance amount in the middle-high range, and lowering the viscous resistance of the actuator and motor, the viscous resistance of the joint Make it smaller,
A robot apparatus characterized by that. In a robot apparatus including at least a torso, an arm, and two or more movable legs and including a plurality of joints,
The movable leg includes at least a thigh, a knee pitch, and an ankle pitch joint, and the arm includes a shoulder and an elbow joint,
The servo controller for the position control system of the actuator that drives each joint has a low gain in the low range and a large phase advance amount in the middle and high range, and a high gain in the entire range and a small phase advance amount in the high range. The actuator motor has a state where the viscous resistance is small and a state where it is large,
The robot apparatus is:
Actuator characteristic control means for combining the gain and phase compensation control of the servo controller of the actuator position control system for driving each joint and the control of the viscous resistance of the actuator motor;
A walking motion control means for controlling the airframe motion during walking using the movable legs,
The actuator characteristic control means, after leaving the rear leg of the two or more support legs, lifting the swing leg forward, swinging it forward, swinging it down, and landing on the floor surface. The servo controller of the actuator that drives each joint of the above has a high gain in all bands and a small phase advance amount in the high band, and increases the viscous resistance of the actuator and motor, thereby increasing the viscous resistance of the joint.
A robot apparatus characterized by that. In a robot apparatus including at least a torso, an arm, and two or more movable legs and including a plurality of joints,
The movable leg includes at least a thigh, a knee pitch, and an ankle pitch joint, and the arm includes a shoulder and an elbow joint,
The servo controller for the position control system of the actuator that drives each joint has a low gain in the low range and a large phase advance amount in the middle and high range, and a high gain in the entire range and a small phase advance amount in the high range. The actuator motor has a state where the viscous resistance is small and a state where it is large,
The robot apparatus is:
Actuator characteristic control means for combining the gain and phase compensation control of the servo controller of the actuator position control system for driving each joint and the control of the viscous resistance of the actuator motor;
A walking motion control means for controlling the airframe motion during walking using the movable legs,
The actuator characteristic control means includes the step of lifting the free leg, swinging it forward, swinging it down and landing on the floor after leaving the rear leg of the two or more support legs. The servo controller of the actuator that drives the thigh joint has high gain in all bands and the phase advance amount in the high range is reduced, and the viscous resistance of the actuator motor is increased to increase the viscous resistance of the joint.
A robot apparatus characterized by that. In a robot apparatus including at least a torso, an arm, and two or more movable legs and including a plurality of joints,
The movable leg includes at least a thigh, a knee pitch, and an ankle pitch joint, and the arm includes a shoulder and an elbow joint,
The servo controller for the position control system of the actuator that drives each joint has a low gain in the low range and a large phase advance amount in the middle and high range, and a high gain in the entire range and a small phase advance amount in the high range. The actuator motor has a state where the viscous resistance is small and a state where it is large,
The robot apparatus is:
Actuator characteristic control means for combining the gain and phase compensation control of the servo controller of the actuator position control system for driving each joint and the control of the viscous resistance of the actuator motor;
A walking motion control means for controlling the airframe motion during walking using the movable legs,
The actuator characteristic control means is a low-frequency and low-gain servo controller for the actuator that drives the ankle joint of the free leg while the rear leg of the two or more support legs is lifted after leaving the floor. And while increasing the amount of phase advance in the mid-high range , the viscous resistance of the joint is reduced by reducing the viscous resistance of the actuator motor .
A robot apparatus characterized by that. In a robot apparatus including at least a torso, an arm, and two or more movable legs and including a plurality of joints,
The movable leg includes at least a thigh, a knee pitch, and an ankle pitch joint, and the arm includes a shoulder and an elbow joint,
The servo controller for the position control system of the actuator that drives each joint has a low gain in the low range and a large phase advance amount in the middle and high range, and a high gain in the entire range and a small phase advance amount in the high range. The actuator motor has a state where the viscous resistance is small and a state where it is large,
The robot apparatus is:
Actuator characteristic control means for combining the gain and phase compensation control of the servo controller of the actuator position control system for driving each joint and the control of the viscous resistance of the actuator motor;
A walking motion control means for controlling the airframe motion during walking using the movable legs,
The actuator characteristic control means is an actuator that drives the knee and ankle joint of the swing leg until the swing leg lifted behind the support leg is swung forward and then swung down to land on the floor. The servo controller of the low-frequency and low-gain and the phase advance amount in the middle-high range is increased, and the viscous resistance of the actuator motor is reduced to reduce the viscous resistance of the joint.
A robot apparatus characterized by that. In a robot apparatus including at least a torso and two or more movable legs and including a plurality of joints,
The movable leg comprises at least a thigh, a knee pitch and an ankle pitch joint;
The servo controller for the position control system of the actuator that drives each joint has a low gain in the low range and a large phase advance amount in the middle and high range, and a high gain in the entire range and a small phase advance amount in the high range. The actuator motor has a state where the viscous resistance is small and a state where it is large,
The robot apparatus is:
Actuator characteristic control means for combining the gain and phase compensation control of the servo controller of the actuator position control system for driving each joint and the control of the viscous resistance of the actuator motor;
Stair ascending / descending operation control means for controlling the airframe operation during stairs ascending / descending using the movable legs,
The actuator characteristic control means is a servo of an actuator for driving each joint of the support legs when two or more movable legs become support legs when the stairs are moved up and down to form a closed link system with the support legs and the floor surface. Increase the controller 's viscous resistance by increasing the phase advance amount in the low / low gain and medium / high range, and increasing the viscous resistance of the actuator / motor ,
A robot apparatus characterized by that. In a robot apparatus including at least a torso and two or more movable legs and including a plurality of joints,
The movable leg comprises at least a thigh, a knee pitch and an ankle pitch joint;
The servo controller for the position control system of the actuator that drives each joint has a low gain in the low range and a large phase advance amount in the middle and high range, and a high gain in the entire range and a small phase advance amount in the high range. The actuator motor has a state where the viscous resistance is small and a state where it is large,
The robot apparatus is:
Actuator characteristic control means for combining the gain and phase compensation control of the servo controller of the actuator position control system for driving each joint and the control of the viscous resistance of the actuator motor;
Stair ascending / descending operation control means for controlling airframe operation at the time of ascending / descending using the movable legs,
The actuator characteristic control means, after leaving the rear leg of the two or more support legs, lifting the swing leg forward, swinging it forward, swinging it down, and landing on the floor surface. The servo controller of the actuator that drives each joint of the above has a high gain in all bands and a small phase advance amount in the high band, and increases the viscous resistance of the actuator and motor, thereby increasing the viscous resistance of the joint.
A robot apparatus characterized by that. The actuator characteristic control means is a servo for an actuator that drives a thigh roll joint of the support leg while lifting the free leg by lifting the rear leg of the two or more support legs when climbing the stairs. The controller has a high gain in the entire band and a small phase advance amount in the high band, and also increases the viscous resistance of the joint by increasing the viscous resistance of the actuator and motor, and the thigh pitch and knee of the free leg. The servo controller of the actuator that drives the joint increases the phase advance amount in the low range and the low gain and in the middle and high range, increases the viscous resistance of the joint, and drives the servo of the actuator that drives the ankle joint of the free leg the controller as well as increasing the amount of phase lead in and mid-high range at low gain in the low range, to reduce the viscosity resistance of the actuator motor To reduce the viscosity resistance of the joint,
The robot apparatus according to claim 8. When the ascending stairs, the actuator characteristic control means sets the servo controller of the actuator that drives the joint of the thigh roll of the swinging leg in the entire band during the period from swinging the lifted swinging leg forward to swinging it down. High gain and small phase advance amount in the high range, increase the viscous resistance of the joint and increase the servo controller of the actuator that drives the joint of the thigh pitch of the free leg in the low range and the low gain and the mid-high range In addition to increasing the phase advance amount at the same time, the viscous resistance of the joint is increased, and the servo controller of the actuator that drives the knee and ankle joint of the free leg has a low gain in the low range and the phase advance amount in the mid-high range. While increasing the size , the viscosity resistance of the joint is reduced by decreasing the viscosity resistance of the actuator / motor .
The robot apparatus according to claim 9. It said actuator characteristic control means, when climbing stairs, at the moment when the swing-down was the free leg is landed, and a mid-high range at low gain servo controller of the actuator in the low range for driving the thigh joints of該遊Ashi In addition to increasing the phase advance amount and increasing the viscous resistance of the actuator and motor, the viscous resistance of the joint is increased, and the servo controller of the actuator that drives the knee and ankle joint of the free leg is reduced in the low range. Increase the phase advance amount in the middle and high range with gain, and reduce the viscous resistance of the joint by reducing the viscous resistance of the actuator motor .
The robot apparatus according to claim 10. When the actuator characteristic control means goes down the stairs, after leaving the rear leg of the two or more support legs, lift up the swing leg, swing it forward, and swing it down until the moment of landing on the floor. In the meantime, the servo controller of the actuator that drives the joint of the thigh of the swing leg has a high gain in all bands and a small amount of phase advance in the high band, and also increases the viscous resistance of the actuator and motor to increase the joint resistance Increase the viscous resistance of the
The robot apparatus according to claim 8. The actuator characteristic control means lowers the servo controller of the actuator that drives the knee and ankle joint of the free leg at the moment of landing on the floor after swinging down the free leg when going down the stairs. In addition to increasing the phase advance amount in the middle and high range with low gain, and reducing the viscous resistance of the actuator and motor, the viscous resistance of the joint is reduced.
The robot apparatus according to claim 12, wherein: In a robot apparatus including at least a torso and two or more movable legs and including a plurality of joints,
The movable leg comprises at least a thigh, a knee pitch and an ankle pitch joint;
The servo controller for the position control system of the actuator that drives each joint has a low gain in the low range and a large phase advance amount in the middle and high range, and a high gain in the entire range and a small phase advance amount in the high range. The actuator motor has a state where the viscous resistance is small and a state where it is large,
The robot apparatus is:
Actuator characteristic control means for combining the gain and phase compensation control of the servo controller of the actuator position control system for driving each joint and the control of the viscous resistance of the actuator motor;
A turning motion control means for controlling the airframe motion during the turning motion using the movable leg,
The actuator characteristic control means is a servo of an actuator for driving each joint of the support leg when two or more movable legs become a support leg during a turning operation and the support leg and the floor surface constitute a closed link system. Increase the controller 's viscous resistance by increasing the phase resistance in the low range, low gain and medium / high range, and increasing the viscous resistance of the actuator / motor ,
A robot apparatus characterized by that. In a robot apparatus including at least a torso and two or more movable legs and including a plurality of joints,
The movable leg comprises at least a thigh, a knee pitch and an ankle pitch joint;
The servo controller for the position control system of the actuator that drives each joint has a low gain in the low range and a large phase advance amount in the middle and high range, and a high gain in the entire range and a small phase advance amount in the high range. The actuator motor has a state where the viscous resistance is small and a state where it is large,
The robot apparatus is:
Actuator characteristic control means for combining the gain and phase compensation control of the servo controller of the actuator position control system for driving each joint and the control of the viscous resistance of the actuator motor;
A turning motion control means for controlling the airframe motion during the turning motion using the movable leg,
The actuator characteristic control means, after leaving one of the two or more support legs, lifting the swing leg, swinging it out, swinging it down, and landing on the floor surface. The servo controller of the actuator that drives each joint has high gain in all bands and the phase advance amount in the high range is reduced, and the viscous resistance of the actuator motor is increased to increase the viscous resistance of the joint.
A robot apparatus characterized by that. The actuator characteristic control means, after leaving one of the two or more supporting legs, lifting the swinging leg, swinging it out, swinging it down, and landing on the floor surface. The servo controller of the actuator that drives the thigh joint has high gain in all bands and the phase advance amount in the high range is reduced, and the viscous resistance of the actuator motor is increased to increase the viscous resistance of the joint.
The robot apparatus according to claim 15. The actuator characteristic control means, after leaving one of the two or more supporting legs, lifting the swinging leg, swinging it out, swinging it down, and landing on the floor surface. The servo controller of the actuator that drives the ankle joint has a low gain in the low range and a large phase advance amount in the middle and high range, and the viscous resistance of the joint is reduced by reducing the viscous resistance of the actuator motor .
The robot apparatus according to claim 15.

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