JP4996042B2 - Robot apparatus and control method thereof, and basic attitude setting method of robot apparatus - Google Patents

Description

  The present invention relates to a robot apparatus having a plurality of movable joints, a control method therefor, and a basic attitude setting method for the robot apparatus, and more particularly, a robot apparatus that controls the movement of each movable joint and controls the attitude of the entire apparatus. The present invention relates to a control method and a basic posture setting method of a robot apparatus.

  More particularly, the present invention relates to a robot apparatus that performs posture control using a predetermined control model, a control method thereof, and a basic attitude setting method of the robot apparatus, and more particularly, an ideal having sufficient rigidity and active characteristics. The present invention relates to a robot apparatus that performs posture control while adapting an actual machine model having passive characteristics to a control model, a control method thereof, and a basic posture setting method of the robot apparatus.

  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.

  Currently, research on legged mobile robots, including biped upright walking, is being actively conducted. This is because the legged mobile robot can cope with uneven walking surfaces such as rough terrain and obstacles and discontinuous walking surfaces such as up and down stairs and ladders. It depends on the reason that it can be realized. On the other hand, since this type of robot is unstable in posture and difficult to control walking, walking control that maintains the stability of the posture is positioned as one of the most important technical issues. Stable “walking” as used herein is defined as “moving with legs without falling down”.

  In many cases, ZMP (Zero Moment Point) is used as a norm for determining the stability of walking for posture stability control of a legged mobile robot. 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 mechanical reasoning, there is a point where the pitch axis and roll axis moments become zero inside the support polygon formed by the sole contact point and the road surface, that is, ZMP (for example, see Non-Patent Document 1). ).

  Target ZMP control has been successful on a real machine by planning the motion to be in dynamic balance at every moment. The biped walking pattern generation based on the ZMP norm has advantages such that a foot landing point can be set in advance and it is easy to consider the kinematic constraint conditions of the foot according to the road surface shape. In addition, using ZMP as a stability determination criterion means that a trajectory is treated as a target value in motion control instead of force, and thus technically feasible.

  Here, the motion control of the robot is basically realized by driving a joint actuator that joins links regarded as substantially rigid bodies. Then, the joint angle at each part is detected by a position sensor arranged in the joint actuator, and control is performed so as to approach the target value.

  For example, in a basic posture having an important meaning in machine control, such as the start point, branch point, and end point of an operation, joint initialization, that is, origin search of a sensor is performed (for example, refer to Patent Document 1). Thereafter, attitude control based on the ZMP trajectory plan or motion control based on other standards is performed.

  In order to realize highly accurate posture stable control, it is preferable that the control model of the robot apparatus has sufficient rigidity, that is, active characteristics. However, the actual machine model has passive characteristics due to backlash in the motor speed reducer, deformation of the frame, and the like. The closer the model used for control is to the characteristics of the actual robot, the more precise control is possible. However, the more complex the model used for control, the more computational complexity increases exponentially.

  For this reason, even if the ideal joint angle on the control model is set as the origin or the reference position for posture control, a deviation occurs between the ideal joint angle and the ideal joint angle due to passive characteristics on the machine model. End up. This deviation causes a situation in which sufficient posture stability control cannot be realized.

  The present inventors consider that an ideal joint angle on the control model in the basic posture of the robot apparatus needs to be calibrated according to the passive characteristics of the mechanical model.

JP 2003-266338 A "Migir Vokobratovic" "LEGGED LOCATION ROBOTS" (Ichiro Kato's "Walking Robot and Artificial Feet" (Nikkan Kogyo Shimbun))

  An object of the present invention is to provide an excellent robot apparatus, a control method therefor, and a basic attitude setting method for the robot apparatus that can control the posture of the entire apparatus by driving and controlling each movable joint.

  A further object of the present invention is to provide an excellent robot apparatus capable of performing posture control while adapting an actual machine model having passive characteristics to an ideal control model having sufficient rigidity and active characteristics, and its control. The present invention provides a method and a basic posture setting method for a robot apparatus.

  A further object of the present invention is to provide an excellent robot apparatus capable of calibrating the ideal origin on the control model of each joint angle in the basic posture of the robot apparatus in accordance with the passive characteristics of the machine model and its control. The present invention provides a method and a basic posture setting method for a robot apparatus.

The present invention has been made in view of the above problems, and in a robot apparatus having a plurality of movable joints,
Driving means for driving each of the movable joints;
Drive control means for controlling the joint position or torque in the movable joint;
Joint position acquisition means for acquiring a joint position in the movable joint;
Torque acquisition means for acquiring drive torque in the movable joint;
A basic posture management means for managing a basic posture of the robot apparatus configured by the movable joint being a predetermined joint position;
The basic posture management means reproduces the joint position of the basic posture on the control model of the robot apparatus on the machine model, and sets the basic posture from which passive characteristic components appearing on the machine model are removed.
It is a robot apparatus characterized by this.

  The control model of the robot apparatus preferably has sufficient rigidity, that is, active characteristics. That is, it is considered desirable in the motion control that the drive unit of the robot apparatus does not have passive characteristics such as backlash. In particular, in order to realize a smooth dynamic motion (dynamic walking), it is considered that it is an essential condition that the drive unit of the robot apparatus to be controlled does not have passive characteristics.

  However, the actual machine model has passive characteristics due to backlash in the motor speed reducer, deformation of the frame, and the like.

  Therefore, in the present invention, the joint position of the basic posture on the control model of the robot apparatus is reproduced on the machine model, and the basic posture is set by removing the passive characteristic component appearing on the machine model. As a result, for example, even if the movable joint has passive characteristics, such as a backlash in the actuator / motor for driving the joint, or a backlash in the speed reducer, the basic posture that is the origin position, Alternatively, the origin position in the basic posture can be suitably set. Of course, the present invention can be applied to the case where the passive characteristic of the movable joint portion changes with time, and automatic origin adjustment using ground contact information can be performed in a legged robot apparatus.

  Therefore, according to the present invention, it is possible to realize a smooth dynamic motion even when the movable joint of the robot apparatus has a passive characteristic or the passive characteristic changes with time. Significant cost reduction is possible.

Here, the basic attitude management means is
Basic posture forming means for driving and controlling the drive means so that the movable joint is at a joint position forming the basic posture;
Basic posture driving torque acquisition means for acquiring the driving torque of the movable joint when the basic posture is formed;
A basic posture fixing device for fixing the robot device to an ideal basic posture on a control model;
Drive torque generation means for generating the drive torque acquired in the basic posture in the movable joint in a state where the robot device is fixed to the basic posture fixing device;
An ideal joint position that sets the current joint position of the movable joint when the driving torque is generated in a state where the robot apparatus is fixed to the basic posture fixing apparatus to an ideal joint position constituting an ideal basic posture Setting means;
The joint position of the movable joint as the actual posture on the machine model when the robot device is released from the basic posture fixing device in a state where the drive torque acquired in the basic posture is generated in the movable joint. A real basic posture acquisition means for acquiring;
Can be configured. Then, an ideal basic posture in which an error from the actual basic posture is a predetermined allowable value or less may be set as the basic posture of the robot apparatus.

  According to the ideal joint position setting means, the ideal joint position can be set by removing passive characteristic components such as backlash of the movable joint by applying torque.

  The robot apparatus can be configured by one or more control target points, a control target point setting link for setting a control target point, a local coordinate origin, and a local coordinate origin setting link for setting a local coordinate origin. In such a case, the basic posture fixing device fixes the control target point setting link and the local coordinate origin setting link so that the robot device is in an ideal basic posture, and the actual basic posture acquisition unit includes: You may make it acquire the attitude | position of the said control object point and the said local coordinate origin when the said robot apparatus is cancelled | released from the said basic attitude fixing apparatus.

  The robot apparatus can be configured as a legged mobile robot having at least a waist, a foot, an arm, and a head. In such a case, the basic posture fixing device fixes the waist, the foot, the arm, and the head so that the robot device is in an ideal basic posture, and the actual basic posture acquisition means is The posture of the waist, the foot, the arm, and the head when the robot device is released from the basic posture fixing device may be acquired.

  Further, in a legged mobile robot, in a basic standing posture, in a joint that requires neutrality such as a hip joint yaw axis, the driving torque is substantially zero at an ideal joint position. In such a case, when the driving torque of the movable joint at the ideal joint position is close to zero, the ideal joint position setting unit is an approximate joint position when the driving torque is shaken by a predetermined value in each direction ±. The midpoint (that is, the midpoint when the gears are moved in the positive and negative directions) may be set as the ideal joint position.

The basic attitude management means includes
Basic posture drive control means for driving and controlling the movable joint so as to fix the robot apparatus to an ideal basic posture on a control model;
Ideal joint position setting means for setting a current joint position of the movable joint in a state in which the robot apparatus is fixed to an ideal basic posture by the basic posture drive control means to an ideal joint position constituting an ideal basic posture; ,
Real basic posture acquisition means for acquiring the joint position of the movable joint that has been drive-controlled to be in a basic posture as an actual posture on a machine model in a state in which the drive control by the basic posture drive control means is cancelled;
The ideal basic posture in which an error from the actual basic posture is equal to or less than a predetermined allowable value may be set as the basic posture of the robot apparatus.

  In the basic posture management means described above, the basic posture fixing device forms an ideal basic posture by mechanically holding the robot device. On the other hand, the basic posture drive control means drives the movable joint so as to have an ideal basic posture on the control model, thereby forming the robot apparatus in the basic posture.

  More specifically, it comprises a measuring means such as a sensor for measuring the positional relationship of the parts of the robot apparatus, and by driving and controlling the movable joint so that the measurement result by the measuring means becomes constant, Fix a specific posture. For example, by installing a distance measuring sensor that measures the distance from the floor surface at the hand or other part, and driving the movable joint so that the output of the distance measuring sensor is constant, the robot apparatus can be in a specific posture. Fixed to.

  According to such a method, a fixing device for mechanically fixing the robot apparatus is not required, and the setting of the origin basic posture and the automatic adjustment work are simplified.

  According to the present invention, an excellent robot apparatus capable of performing posture control while adapting an actual machine model having passive characteristics to an ideal control model having sufficient rigidity and active characteristics, and its control method In addition, a basic posture setting method for the robot apparatus can be provided.

  Further, according to the present invention, an excellent robot apparatus capable of calibrating the ideal origin on the control model of each joint angle in the basic posture of the robot apparatus according to the passive characteristics of the machine model, and its A control method and a basic posture setting method for a robot apparatus can be provided.

  According to the present invention, the joint position of the basic posture on the control model of the robot apparatus can be reproduced on the machine model, and the basic posture can be set with the passive characteristic component appearing on the machine model removed. As a result, even if the movable joint has passive characteristics such as rattling in the actuator / motor for driving the joint, backlash in the speed reducer, etc., the basic posture or basic The origin position in the posture can be suitably set. Of course, the present invention can be applied to the case where the passive characteristic of the movable joint portion changes with time, and automatic origin adjustment using ground contact information can be performed in a legged robot apparatus.

  Therefore, according to the present invention, it is possible to realize a smooth dynamic motion even when the movable joint of the robot apparatus has a passive characteristic or the passive characteristic changes with time. Significant cost reduction is possible.

  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. Robot Configuration FIGS. 1 and 2 show a state in which the “humanoid” or “humanoid” robot device 100 used for carrying out the present invention is viewed from the front and rear, respectively. Yes. As shown in the figure, the robot apparatus 100 includes a trunk, a waist, a head, left and right upper limbs, and left and right lower limbs that perform legged movement, and is built in, for example, the trunk. The operation of the robot apparatus is comprehensively controlled by a control unit (not shown).

  Each of the left and right lower limbs is composed of a thigh, a knee joint, a shin part, an ankle, and a foot, and is connected to the lowermost part of the waist by a hip joint. 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 waist by a neck joint.

  The robot apparatus 100 configured as described above can realize bipedal walking by whole body cooperative operation control by a control unit (not shown in FIGS. 1 and 2). 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 control unit includes a controller (main control unit) that processes external inputs from the joint actuators and sensors (described later) constituting the robot device 100, a power circuit, and other peripheral devices. Is the body. In addition, the control unit may include a communication interface and a communication device for remote operation.

  The walking control in the robot apparatus 100 is realized by planning a target trajectory of the lower limb in advance and correcting the planned trajectory in each of the above periods. For example, 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.

  ZMP is used as a norm for determining the stability of walking for posture stability control of the robot apparatus including correction of walking motion trajectory. For this reason, interpolation calculation using a fifth-order polynomial is performed so that the position, speed, 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 the dynamic reasoning of the principle, there is a point where the pitch axis and roll axis moments become zero, that is, ZMP, inside the support polygon (that is, the ZMP stable region) formed by the sole contact point and the road surface.

  FIG. 3 schematically shows the joint degree-of-freedom configuration of the robot apparatus 100. As shown in the figure, the robot apparatus 100 includes an upper limb that includes two arms and a head 1, a lower limb that includes two legs that realize a moving operation, and a trunk that connects the upper limb and the lower limb. And a structure having a plurality of limbs composed of the waist.

  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 a and 2 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.

  Further, each leg part 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.

  However, the robot apparatus 100 does not have to be equipped with all the above-described degrees of freedom or is not limited to this. It goes without saying that the degree of freedom, that is, the number of joints, can be increased or decreased as appropriate in accordance with design / manufacturing constraints and required specifications.

  Each degree of freedom of the robot apparatus 100 as described above is actually mounted using a rotary actuator, and motion control is performed based on these rotational position controls. These joint actuators must be small and light because of the need to eliminate extra bulges in appearance and approximate human body shape, and to perform posture control on unstable structures such as biped walking. Is preferred.

  In this embodiment, a small AC servo actuator of a gear direct connection type and a servo control system of a single chip built in a motor unit is mounted. This type of AC servo actuator is disclosed in, for example, Japanese Patent Laid-Open No. 2000-299970 already assigned to the present applicant. Each joint actuator is provided with a torque sensor for detecting motor torque and an angle / position sensor for detecting a rotational position or a joint position.

  Further, in this embodiment, by adopting a reduced speed gear as the direct connection gear of the actuator / motor, the passive characteristic of the drive system required for the robot 100 of the type that places importance on physical interaction with humans is obtained. ing.

  FIG. 4 schematically shows a control system configuration of the robot apparatus 100. As shown in the figure, the robot apparatus 100 is adapted to each mechanism unit 30, 40, 41, 50R / L, 60R / L expressing 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 overall operation of the robot apparatus 100 is comprehensively controlled by the control unit 80. The control unit 80 exchanges data and commands with a main control unit 81 including 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).

  The peripheral circuit 82 referred to here is an interface for connecting external peripheral devices, charging stations (not shown), and other peripheral devices connected through cables and radio, in addition to peripheral devices mounted on the robot apparatus.・ Include connectors.

  In realizing the present invention, the installation location of the control unit 80 is not particularly limited. Although it is mounted on the trunk unit 40 in FIG. 4, it may be mounted on the head unit 30. Alternatively, a control unit 80 may be provided outside the robot apparatus 100 to communicate with the robot apparatus 100 main body by wire or wirelessly.

Each degree of freedom of joint in the robot apparatus 100 shown in FIG. 3 is realized by a corresponding actuator. That is, the head unit 30 includes a neck joint yaw axis actuator M ₁ , neck joint pitch axis actuator M ₂ , neck joint roll representing the neck joint yaw axis 1, neck joint pitch axis 2, and neck joint roll axis 3. axis actuator M ₃ is disposed.

The trunk unit 40 is provided with a trunk pitch axis actuator M ₉ and a trunk roll axis actuator M 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 M ₄ , shoulder joint roll axis actuator M ₅ , upper arm yaw axis actuator M ₆ , elbow joint pitch axis actuator M ₇ representing each of yaw axis 6, elbow joint pitch axis 7, and wrist joint yaw axis 8. , wrist joint yaw axis actuator M ₈ is arranged.

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

The actuators M ₁ , M ₂ , M ₃ ... Used for each joint are more preferably a small AC servo actuator of the type directly mounted on a gear and mounted in a motor unit with a servo control system integrated into a single chip. ).

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

  A posture sensor 95 and an acceleration sensor 96 are disposed on the trunk 40. The acceleration sensor 96 is arranged in each XYZ axial direction. Further, by providing an acceleration sensor 96 on the waist 41, the waist 41, which is a part with a large mass operation amount, is set as a control target point, and the posture and acceleration at that position are directly measured, and the posture based on ZMP Stable control can be performed. The attitude sensor 95 and the acceleration sensor 96 are configured as an acceleration sensor A1 and a gyro sensor G1, respectively, in FIG.

  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. In FIG. 3, sensors A2 and A3 for measuring acceleration at the foot and gyro sensors G2 and G3 for measuring the posture of the foot are arranged on the left and right ankles, respectively. In addition, force sensors F1 to F4 and F5 to F8 for measuring ground contact and floor reaction force are disposed at the four corners of the left and right soles.

  Here, when the acceleration sensor is arranged only on the waist 41 that is a part where the mass operation amount is large, only the waist 41 is set as the control target point, and the state of the foot is relative to the calculation result of the 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 are used. An acceleration sensor for directly measuring is provided. As a result, the ZMP balance equation can be assembled directly at the foot closest to the ZMP position. Therefore, more rigorous posture stabilization control can be realized at high speed. As a result, even on a gravel where the road surface moves when force or torque is applied, on a carpet with long bristle feet, or on a residential tile that cannot easily secure a sufficient translational friction coefficient, it can easily slide. The stable walking (motion) of the device can be guaranteed.

  The main control unit 80 can dynamically correct the control target in response to the outputs of the sensors A1 to A3, G1 to G3, and F1 to F8. More specifically, adaptive control is performed on each of the sub-control units 35, 45, 55, and 65 to realize a whole body movement pattern in which the upper limbs, trunk, and lower limbs of the robot apparatus 100 are driven in cooperation. To do.

The whole body movement of the robot apparatus 100 sets foot movements, ZMP trajectories, trunk movements, upper limb movements, waist heights, etc., and commands for instructing movements according to these setting contents to the sub-control units 35, Forward to 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 each actuator _{M 1, M 2, M 3} .... Here, “ZMP” refers to a point on the floor where the moment due to floor reaction force during walking is zero, and “ZMP trajectory” refers to, for example, ZMP during the walking motion period of the robot 100. It means the trajectory that moves.

  The legged mobile robot can use ZMP as a norm for determining the stability of walking. The stability criterion for ZMP is that the system forms an appropriate ZMP space, and if there is ZMP inside the support polygon, the system does not generate rotational or translational motion, and solves the equations of motion related to rotation and translation. There is no need. On the other hand, when there is no ZMP inside the support polygon or when there is no support action point for the outside world, it is necessary to solve the equation of motion instead of the ZMP equation. For example, since a support polygon does not exist at the time of getting off, such as when jumping or jumping off a hill, the equation of motion may be solved instead of the ZMP equation.

The ZMP equation describes the balance relationship of each moment on the target ZMP. Represents robotic device in a number of mass points m _i, when the these control target points to determine the trajectory of the respective control points the sum becomes zero moment in all of the controlled object point on the target ZMP generated in m _i Formula Is the ZMP balance equation.

  The ZMP balance equation described in the world coordinate system (O-XYZ) and the ZMP balance equation described in the local coordinate system (O-X′Y′Z ′) of the robot apparatus are as follows.

Each of the above equations represents the sum of moments around the ZMP (radius r _i −P _zmp ) generated by the acceleration component applied at each mass point (or control target point) m _i and the applied j-th external force moment. the sum of M _j, describes that the sum of the moments of ZMP around produced by an external force F _k (a point of action of k-th external force F _k and S _k) is balanced.

  This ZMP balance equation includes a floor reaction force moment (moment error component) T in the target ZMP. By suppressing this moment error to zero or within a predetermined allowable range, the posture stability of the robot apparatus is maintained. In other words, correcting the movement (such as the foot movement and the trajectory of each part of the upper body) so that the moment error is zero or less than the allowable value is the essence of posture stabilization control using ZMP as a stability criterion. It is.

  As described above, when the acceleration sensor is provided on the foot sole that is the contact portion with the road surface, the local coordinate system of the real robot with respect to the world coordinate system is set, and the foot sole as the origin is set. And the ZMP balance equation can be derived directly. Furthermore, by arranging an acceleration sensor at a control target point having a large mass manipulated variable including the waist 41, the moment amount around the ZMP for each control target point can be directly derived using the acceleration sensor output value. Can do.

  Here, since a real robot as a control target is a mobile device, it is difficult to obtain a position vector on the world coordinates at each control target point. As an alternative, the position vector of the control target point on the local coordinates is obtained by a relatively easy calculation method such as inverse kinematics calculation. Therefore, the actual posture stabilization process may be performed using the latter ZMP balance equation described in the local coordinate system (O-X′Y′Z ′) of the robot apparatus. (Since it is difficult to accurately measure the ZMP trajectory in the world coordinate system with the state detector mounted on the robot, an external measuring instrument fixed to the world coordinate system is generally required. On the other hand, the ZMP trajectory can be obtained accurately and directly in local coordinates by measuring the ZMP trajectory by placing the load sensors F1 to F8 on the ground contact portion. In addition, in the present embodiment, in the local coordinate system, it is possible to directly measure information that is dominant in high-speed motion by arranging an acceleration sensor near the local coordinate origin. ZMP balance equation is used.)

  Note that the robot apparatus 100 according to the present embodiment has a center of gravity set at the waist position, is an important control target point for posture stability control, and constitutes a “base” of the apparatus.

B. The setting of the basic posture of the robot device and the adjustment of the basic posture The control model of the robot device preferably has sufficient rigidity, that is, active characteristics. That is, it is considered desirable in the motion control that the drive unit of the robot apparatus does not have passive characteristics such as backlash. In particular, in order to realize a smooth dynamic motion (dynamic walking), it is considered that it is an essential condition that the drive unit of the robot apparatus to be controlled does not have passive characteristics.

  However, the actual machine model has passive characteristics due to backlash in the motor speed reducer, deformation of the frame, and the like.

  Further, the closer the model used for control is to the characteristics of the actual robot, the more precise control becomes possible. However, the more complicated the model used for control, the more computational complexity increases.

  Considering the current digital computer technology that is not good at interference and non-linear operations, for robot systems where high real-time controllability is desired, the model used for control is a simple model with no interference and high linearity (that is, A rigid body model that does not deform even when a force is applied is practical.

  The higher the rigidity of the target robot and the higher the vibration damping property, the more active control is possible up to a higher frequency range. For this purpose, it is necessary to increase the control cycle, and a certain cycle (for example, 4 mm). Since general-purpose parts can no longer be used from about a second), the cost increases rapidly. Therefore, the cost can be reduced if the control period is limited to about 4 milliseconds. Strictly speaking, a control cycle of 0.1 milliseconds or more is desired for the control of a legged mobile robot with a high-speed switching operation of an open / close link or a collision operation on an unknown walking road surface.

  From the above consideration, the robot system according to the present embodiment employs an active / passive control system. In particular,

(1) The model used for the control is a rigid body model or a mass system model, and secures real-time performance in a cheaper computer system.
(2) Due to the cost of the entire control system, the active control period is limited to about 4 milliseconds.
(3) For a band in which a control period of 4 milliseconds or more is desired, passive control based on the ZMP behavior space arrangement (for example, see Japanese Patent Application Laid-Open No. 2003-157696 already assigned to the present applicant). Do.

  However, in an attitude where the control ratio of passive control and active control is largely switched as it is, a large error is likely to occur discontinuously between the model used for control and the actual robot state, thereby making the robot operation unstable. . Therefore, in such an attitude (referred to as “basic attitude” in this specification), matching with the control model used is strictly taken by the origin setting method described below. As a result, stable control can be realized at low cost without requiring an unrealistic control cycle.

  In the present embodiment, the joint position of the basic posture on the control model of the robot apparatus is reproduced on the machine model, and the basic posture is set by removing the passive characteristic component appearing on the machine model. As a result, for example, even if the movable joint has passive characteristics, such as a backlash in the actuator / motor for driving the joint, or a backlash in the speed reducer, the basic posture that is the origin position, Alternatively, the origin position in the basic posture can be suitably set. Of course, the present invention can be applied to the case where the passive characteristic of the movable joint portion changes with time, and automatic origin adjustment using ground contact information can be performed in a legged robot apparatus. The origin position referred to here corresponds to, for example, the origin position of the optical origin sensor attached to the actuator / motor. The basic posture corresponds to the basic posture at the time of origin search.

  The robot apparatus according to the present embodiment has a plurality of joint degrees of freedom as already described with reference to FIG. Each movable joint has a reference position. In this specification, the reference position of the joint is referred to as the origin, and a series of operations for determining the reference position is referred to as “origin investigation”. The origin investigation can be roughly classified as follows for each part. The joint reference position mentioned here corresponds to an indirect home position (effectively 0 degrees).

(1) Origin survey of trunk, legs, and arms (2) Origin survey of head (3) Origin survey of wrist

  The following description will focus on (1) investigation of the origin of the trunk, legs, and arms.

B-1. Thought of origin investigation Origin origin investigation is to determine the reference position of each joint, and is roughly divided into the following two determination methods.

(1) Method of determining an absolute angle for each joint (2) Method of fixing the root and end and determining the angle relatively

  FIG. 5 illustrates an example of a method for determining an absolute angle for each joint. In this case, the reference position is represented by the joint position (θ1, θ3) possessed by the link joined by the joint and the angle θ2 formed by the two links joined by the same joint.

  According to this method, the angle of each joint can be accurately determined, but there are various errors in the actual robot apparatus, and the link length may be different. In this case, even if the two robot devices have the same angle, the end of the link comes to a different position. That is, the angles of the joints corresponding to each other between the robot apparatuses are the same, but the end positions are different due to the difference in the link length (see FIG. 6).

FIG. 7 illustrates an example of a method of fixing the root and end and relatively determining the angle. In this method, when the robot takes a certain posture, its end is forcibly fixed at a place where it should theoretically come, and the angle of the joint at that time is regarded as a theoretical angle. Thus, if the link length is different from the theoretical value, the resulting criterion is different from the true angle (see FIG. 8). However, in any robotic device, end all come to the same position, advantage states that your Oh when the took the same attitude. That is, the true angles of the corresponding joints differ between the robot apparatuses, but the ends are at the same position.

  In this embodiment, the latter origin investigation method is adopted from the viewpoint of placing the highest priority on the basic posture that is the starting point of the motion. By the way, the basic posture of the trunk and legs is the posture that becomes the base point of walking motion, and the arm is the posture of camera calibration.

B-2. Principle of Origin Investigation As shown in FIG. 7, a link mechanism comprising left and right end joints, links joined to these end joints, and a central joint joining the other ends of these links is taken as an example. The angles formed by the links with respect to the respective ends are θ1 and θ3, and the angle formed by the links via the central joint is θ2. In this case, among the three joints, by fixing the joints at both ends, θ1 to θ3 are automatically determined based on the triangular congruence condition that the three sides are equal.

  By applying this principle, for example, the origin of the leg of the robot apparatus can be investigated. As shown in FIG. 3, the leg includes a hip joint (yaw axis, pitch axis, roll axis), a thigh link, a knee joint (pitch axis), a shin frame, and an ankle joint (pitch axis). , Roll shaft), and the same link mechanism as that shown in FIG. Here, as shown in FIG. 9, the foot of the foot is fixed by the foot panel on the floor, the hip joint is supported by the base frame, and the base frame and the foot panel are relatively positioned. By doing so, the root and the end of the link mechanism are fixed, and the angles θ1 to θ3 are relatively determined.

  However, as a modified example of FIG. 9, instead of using the base frame, a distance sensor that measures the height from the floor surface to the hip joint with a foot placed on the foot panel is used. By controlling the posture so as to keep constant, it is possible to obtain the same effect as when the base frame is used.

  An example is shown in FIG. In the example shown in the figure, two distance measuring sensors are mounted on the waist part 41, the distance to the floor surface is measured in each, and the height of the waist part 41 and the posture of the waist part 41 are calculated. The posture of the leg can be fixed by making these values constant.

  In the example shown in FIG. 22, a distance measuring sensor and an angle measuring sensor are mounted at two locations of the waist 41. One distance measurement sensor and angle measurement sensor measure the distance to the floor and the inclination. The other distance measuring sensor and angle measuring sensor measure a distance and an inclination with respect to a target attached to another part such as an arm. Based on these measurement results and inverse kinematics calculation, the height of the waist 41 and the posture of the waist 41 are calculated, and the posture of the leg can be fixed by making these values constant. .

  FIG. 10 shows a configuration example of the fixing device of the robot apparatus that is used to fix the base and end of each link mechanism constituting the robot apparatus and relatively determine the angle.

  The illustrated fixing device is configured to be able to perform the origin investigation of the trunk, leg, and arm based on the principle of determining the joint angle relatively by fixing the base and end of the link mechanism. .

  On the pedestal, a foot panel that fixes the foot of the foot and a base frame that regulates the relative position of the pedestal or the foot panel at the hip joint are arranged. The hip joint (yaw axis, pitch axis, roll axis) ), Thigh link, knee joint (pitch axis), shin frame, hip joint corresponding to the root of the link mechanism consisting of ankle joint (pitch axis, roll axis) and ankle joint corresponding to the end This makes it possible to investigate the origin at the relevant part.

  Further, the shoulder frame and the wrist frame are guided by two guide rails disposed on the pedestal and having parallel movement directions, and can advance or retract in the front-rear direction. Therefore, in the trunk link mechanism composed of the shoulder joint, trunk joint, and hip joint, the hip joint is fixed to the base frame, and the shoulder frame is further advanced to the robot apparatus side to secure the shoulder. The hip joint corresponding to the root and the shoulder joint corresponding to the end can be fixed, and the origin of the part can be investigated.

  The arm part of the robot device is a link mechanism composed of a shoulder joint, an upper arm link, an elbow joint, a forearm link, a wrist, and a back of a hand. By fixing the wrist to the frame, the shoulder joint corresponding to the base of the link mechanism and the wrist joint corresponding to the end can be fixed, and the origin can be investigated at the site.

  Here, an actuator / motor is used to realize the drive of the movable joint, but in order to obtain a higher output torque, a reduction gear is generally provided at the output end of the motor. For example, a planetary gear mechanism is applied to the speed reducer. The planetary gear mechanism is a gear structure composed of a sun gear as a star, a planetary gear as a planet, and an internal gear that defines the revolution orbit of the planetary gear. In addition, the planetary gear mechanism connects the axis centers of the planetary gears. Has a planetary carrier. According to the speed reducer using the planetary gear mechanism, it is possible to reduce the speed on the same axis as the drive shaft, so that a strong reduction ratio can be obtained by connecting multiple stages.

  Regardless of the speed reducer structure, the motor-side gear and the output-side gear are modeled, and torque is transmitted by their meshing relationship (see FIG. 11). As is well known to those skilled in the art, there is a backlash called backlash between the gears that transmit torque, which contributes to the passive characteristics of an actual robot.

  Even if the joint angle as described above is determined in a state having passive characteristics such as backlash, there is a problem in that the origin position cannot be determined because variations in the passive characteristic component occur depending on the fixed state.

  Therefore, in the present embodiment, as shown in FIG. 12, during the origin investigation, a torque in a predetermined direction is applied to the gear on the motor side to bring the teeth closer (that is, contact with the opposing surface of the gear on the output side). Thus, stable positioning with very little variation due to passive characteristics is performed.

In the actual origin investigation, the direction and magnitude of the torque generated in each joint in the basic posture is taken into consideration, and the amount of torque applied to the rotating shaft in which direction and how much torque should be applied is set. For joints that require neutrality, such as the yaw axis of a hip joint, the gears are moved toward the positive and negative directions, and the midpoint is used as a reference. Details of the origin investigation method will be described later.

B-3. The joint angle at each part of the origin return is detected by installing a position sensor on the joint actuator. It is said that an actuator that employs a relative coordinate system rather than an absolute coordinate system can achieve higher accuracy. Here, when the relative position sensor is used, it is necessary to initialize the joint, that is, search for the origin of the sensor at the time of activation. In this specification, the search for the origin is referred to as “origin return” (in a narrow sense).

  Further, the reference position (0 degrees of the joint) of each joint is defined by, for example, the basic posture, but how many distances it is from the origin defined in the joint actuator (hereinafter referred to as “origin data”) Also called). In the actual posture control of the robot apparatus, the actuator / motor is rotated based on the origin data and moved to the reference position of each joint. In this specification, these series of operations will be referred to as “return to origin” (in a broad sense).

  FIG. 13 illustrates a procedure for returning the origin of the joint actuator.

  Since the relative position sensor is used at startup, the current angle of the joint actuator is unknown. Therefore, the actuator / motor is first rotationally driven, and first, the origin position serving as a reference for the actuator / motor itself is searched. That is, origin return in a narrow sense is executed.

  Subsequently, the joint is rotated to the reference position based on the origin data, that is, the displacement θ between the reference position of the joint and the origin position of the actuator motor itself. That is, the origin return in a broad sense is executed.

  In the following, the origin investigation procedure for one joint actuator will be described with reference to FIGS. 14 to 18 using a simple model in which two links are rotatably joined by the joint actuator.

  When an origin return command for origin investigation is input to the actuator / motor drive device, first, origin data of the joint to be origin investigation is erased. Subsequently, the actuator rotates and searches for the origin sensor of the actuator (see FIG. 14). This corresponds to narrow-point origin return.

And after an origin sensor is discovered, it fixes according to the basic attitude | position of a robot apparatus using the fixing device for an origin investigation which fixes the other end of both links (refer FIG. 15). The joint angle at this time corresponds to the joint angle that realizes the basic posture of the robot device, and the joint is maintained at the joint angle that realizes the basic posture by the fixing device.

  During this time, the angle α rotated for the actuator to shift from the origin position by the origin sensor to the basic posture is stored.

  When the origin investigation command is executed after fixing the origin investigation fixing device, the actuator motor serving as the target joint rotates in order with a predetermined torque and direction to reduce backlash. The amount of further rotation is stored by the torque applied at this time (β), and the angle obtained by adding α and β becomes the ideal angle (ψ) from the origin position to the basic posture by the origin sensor. After that, the angle (θ) from the origin position to the joint reference position by the origin sensor is obtained using the theoretical angle between the joint reference position and the basic posture of the robot.

From θ−ψ = γ−ε θ = ψ + (γ−ε)

  Where θ is the angle from the origin position by the origin sensor to the joint reference position, ψ is the angle from the origin position to the basic posture by the origin sensor, γ is the theoretical angle of the joint reference position in the robot, and ε is the robot This is the theoretical angle of the basic posture.

  Next, the passive characteristics of the joints due to gear backlash and backlash are investigated. As shown in FIG. 12, by applying a torque in a predetermined direction to the gear on the motor side and bringing the teeth closer (that is, contacting the opposite surface of the gear on the output side), stability with very little variation due to passive characteristics is achieved. Positioning is performed.

  At this time, in consideration of the direction and magnitude of the torque generated in each joint during the basic posture, it is set how much torque should be applied to the rotating shaft in which direction. Further, when the backlash is filled, torque is applied not only in a predetermined direction but also in the reverse direction.

  The angle δ rotated by the torque applied in the opposite direction is defined as the backlash amount or passive characteristic value of the joint, and is recorded as the passive characteristic data of the joint (see FIG. 17).

  For joints that require neutrality, such as the yaw axis of a hip joint, the gears are moved toward the positive and negative directions, and the midpoint is used as a reference.

  According to such a series of procedures, the joint reference position is determined, origin data and passive characteristic data are created, and the origin survey is completed. The obtained origin data and passive characteristic data are recorded in association with the same file, or are recorded in association with each other as separate files.

  FIG. 18 summarizes the operation procedure for returning to the origin.

  Since the relative coordinate system is adopted, the current angle of the actuator is not known at startup.

  Here, origin return in a narrow sense is performed. That is, the actuator rotates and starts searching for the origin sensor of the actuator.

  Then, based on the origin data that the reference position of the joint is rotated by θ degrees from the origin of the actuator, the joint is rotated to the reference position.

B-4. Origin search of the entire robot apparatus Normal origin investigation is performed in parallel on the entire robot apparatus, that is, the joint actuators of the whole body, based on the origin investigation process for each joint actuator as described above.

  As described above, the fixing device shown in FIG. 10 is based on the principle that the joint angle is relatively determined by fixing the root and end of the link mechanism, and the root and end of each link mechanism constituting the robot apparatus. The angle is fixed and the angle is relatively determined, and can be used for the origin investigation of the trunk, legs, and arms.

  That is, on the pedestal, a foot panel that fixes the foot of the foot and a base frame that regulates a relative position of the pedestal or the foot panel at the hip joint part are disposed, and the hip joint, the thigh link, The hip joint corresponding to the base of the link mechanism including the knee joint, the shin part frame, and the ankle joint and the ankle joint corresponding to the end are fixed, and the origin can be investigated at the site.

  Further, the shoulder frame and the wrist frame are guided by two guide rails disposed on the pedestal and having parallel movement directions, and can advance or retract in the front-rear direction. Therefore, in the trunk link mechanism composed of the shoulder joint, trunk joint, and hip joint, the hip joint is fixed to the base frame, and the shoulder frame is further advanced to the robot apparatus side to secure the shoulder. The hip joint corresponding to the root and the shoulder joint corresponding to the end can be fixed, and the origin of the part can be investigated.

Also, by fixing the shoulder to the shoulder frame and the wrist to the wrist frame, the root of the link mechanism consisting of the shoulder joint, upper arm link , elbow joint, forearm link and wrist, and back of the hand It is possible to realize the fixation of the shoulder joint corresponding to and the wrist joint corresponding to the end, and the origin investigation at the part can be performed.

  FIG. 19 shows a processing procedure for performing the origin investigation processing of the robot apparatus using the fixing device shown in FIG. 10 in the form of a flowchart.

  First, a basic posture to be subjected to origin investigation is selected (step S1), and a torque generated by each joint actuator in the basic posture is measured (step S2). Thereby, the torque information of the actuator in the basic posture can be acquired.

  Subsequently, the robot apparatus is attached by, for example, a fixing apparatus as shown in FIG. 10, and the waist, legs, arms, and head are mechanically fixed so that the ideal basic posture is obtained (step S3).

  Here, the robot apparatus is considered to be composed of one or more control target points, a control target point setting link for setting the control target point, a local coordinate origin, and a local coordinate origin setting link for setting the local coordinate origin. In this case, step S3 corresponds to fixing the control target point setting link and the local coordinate origin setting link by the fixing device (step S8).

  Then, using the torque information of each joint actuator in the basic posture measured in step S2, torque is generated in each joint actuator (step S4).

  Next, the joint actuator is set from the current angle to the ideal joint angle (step S5). That is, components caused by the passive characteristics of the joint such as backlash are canceled by applying torque.

Here, the torque information obtained in step S2 is the case was near zero, shaking generated torque ± in each direction, to set a medium point of the joint angles in the respective ideal joint angle. For example, in a joint that requires neutrality, such as the yaw axis of a hip joint, the gear is moved in both positive and negative directions, and the midpoint is used as a reference.

  Then, the robot device is released from the fixed device, and the postures of the waist, feet, head, and arms in the basic posture are measured (step S6).

  If the robot apparatus is considered to be composed of one or more control target points, a control target point setting link for setting the control target point, a local coordinate origin, and a local coordinate origin setting link for setting the local coordinate origin, S6 corresponds to measuring the postures of the control target point setting link and the local coordinate origin setting link in the basic posture (step S9).

Then, the ideal basic attitude on the obtained control model in step S3, the deviation comparing the basic position on the resulting machine model in step S6, if the allowable value or less, the current angle of the joint actuator, The ideal joint angle for realizing the ideal basic posture is set, and the entire processing routine ends.

  On the other hand, if the deviation between the control model and the machine model exceeds the allowable value, the process returns to step S2, and the same processing as described above is repeatedly executed until the deviation falls below the allowable value.

  In addition, as described above, instead of using a fixing device such as a base frame, a distance sensor that measures the height from the floor to the hip joint or other measuring device is used, and the measured value such as the distance is By controlling the posture so as to keep it constant, it is possible to obtain the same effect as when the fixing device is used.

  In FIG. 20, the origin search processing of the robot apparatus is performed using the drive control of each joint actuator so as to be fixed to an ideal basic posture on the control model using a measurement mechanism such as a distance sensor. The processing procedure is shown in the form of a flowchart.

  First, the environment is recognized using a grounding confirmation sensor, a tilt sensor, a gyro sensor, an acceleration sensor or the like mounted on the robot apparatus (step S11).

  Then, it is determined whether or not the recognized physical external environment is suitable for the origin search process to be performed thereafter (step S12). For example, when the robot apparatus is currently in an unsuitable environment such as standing on rough terrain, the environment is changed by moving the place (step S13), and the environment is recognized again.

  Then, in a suitable physical environment, a basic posture that is a subject of origin investigation is selected (step S14).

  Next, by using a distance sensor that measures the height from the floor to the hip joint and other measurement devices, posture control is performed so that measured values such as distance are kept constant, so that the waist and feet of the robotic device The arm part and the head part are each fixed so as to have the ideal basic posture (step S15).

  Here, the robot apparatus is considered to be composed of one or more control target points, a control target point setting link for setting the control target point, a local coordinate origin, and a local coordinate origin setting link for setting the local coordinate origin. In this case, step S15 corresponds to fixing the control target point setting link and the local coordinate origin setting link by posture control (step S16).

  Next, the joint actuator is set from the current angle to the ideal joint angle (step S17). That is, components caused by the passive characteristics of the joint such as backlash are canceled by applying torque.

  Then, the fixation by the posture control that keeps the measurement value constant is released, and the postures of the waist, feet, head, and arms in the basic posture are measured (step S18).

  If the robot apparatus is considered to be composed of one or more control target points, a control target point setting link for setting the control target point, a local coordinate origin, and a local coordinate origin setting link for setting the local coordinate origin, S18 corresponds to measuring the attitudes of the control target point setting link and the local coordinate origin setting link in the basic attitude (step S19).

Then, the ideal basic attitude on the obtained control model in step S17, the deviation comparing the basic position on the resulting machine model by step S18, if less than the allowable value, the current angle of the joint actuator, The ideal joint angle for realizing the ideal basic posture is set, and the entire processing routine ends.

  On the other hand, if the deviation between the control model and the machine model exceeds the allowable value, the process returns to step S15, and the same processing as described above is repeatedly executed until the deviation falls below the allowable value. Or it returns to step S14 and reselects a basic posture.

  The origin investigation of the robot apparatus does not necessarily need to cover all joint actuators of the entire robot apparatus, that is, the whole body. For example, in order to simplify the work of demonstration and maintenance, it is possible to perform the origin investigation process by limiting the parts such as only the legs and only the arms.

  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 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 “humanoid” or “humanoid” robot apparatus 100 used for carrying out the present invention is viewed from the front. FIG. 2 is a view showing a state in which the “humanoid” or “humanoid” robot apparatus 100 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 robot apparatus 100. FIG. 4 is a diagram schematically showing a control system configuration of the robot apparatus 100. FIG. 5 is a diagram for explaining a method of determining the joint reference position. FIG. 6 is a diagram for explaining a method of determining the joint reference position. FIG. 7 is a diagram for explaining a method of determining the joint reference position. FIG. 8 is a diagram for explaining a method of determining the joint reference position. FIG. 9 is a diagram for explaining a method of fixing the base and end of the link mechanism constituting the robot apparatus and relatively determining the angle. FIG. 10 is a diagram showing a fixing device of the robot device used for fixing the base and end of each link mechanism constituting the robot device and relatively determining the angle. FIG. 11 is a diagram illustrating a model of a reduction mechanism of an actuator / motor for joint driving. FIG. 12 is a diagram for explaining a method of conducting an origin investigation in a state where the reduction gear has passive characteristics. FIG. 13 is a diagram for explaining a procedure for returning to the origin of the joint actuator. FIG. 14 is a diagram for explaining a procedure of origin investigation for one joint actuator. FIG. 15 is a diagram for explaining a procedure of origin investigation for one joint actuator. FIG. 17 is a diagram for explaining the procedure of origin investigation for one joint actuator. FIG. 17 is a diagram for explaining the procedure of origin investigation for one joint actuator. FIG. 18 is a diagram for explaining a procedure for returning to the origin for one joint actuator. FIG. 19 is a flowchart showing a processing procedure for performing the origin investigation processing of the robot apparatus using the fixing device shown in FIG. FIG. 20 is a diagram for performing the origin investigation process of the robot apparatus by using the drive control of each joint actuator so as to fix the ideal basic posture on the control model using a measurement mechanism such as a distance sensor. It is the flowchart which showed the processing procedure. FIG. 21 is a diagram for explaining a mechanism for conducting an origin investigation using a distance measuring sensor. FIG. 22 is a diagram for explaining a mechanism for conducting an origin investigation using a distance measuring sensor and an angle measuring sensor.

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, 41 ... Lumbar 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 ... ankle unit 80 ... control unit, 81 ... main control unit 82 ... peripheral circuit 91, 92 ... grounding confirmation sensor 93, 94 ... acceleration sensor 95: Posture sensor 96 ... Acceleration sensor 100 ... Legged mobile robot

Claims (7)

In a robot apparatus including one or more control target points, a control target point setting link for setting a control target point, a local coordinate origin, a local coordinate origin setting link for setting a local coordinate origin, and a plurality of movable joints,
Driving means for driving each of the movable joints;
Drive control means for controlling either the joint position or torque in the movable joint;
Joint position acquisition means for acquiring a joint position in the movable joint;
Torque acquisition means for acquiring drive torque in the movable joint;
Attitude acquisition means for acquiring the attitude of the control target point setting link and the local coordinate origin setting link;
Basic attitude management means for managing basic attitudes of the control target point setting link and the local coordinate origin setting link formed by the movable joint becoming a predetermined joint position;
The basic posture management means includes
Said controlled object point setting link and the local coordinate origin established link with no attached to the basic position fixing device for fixing the basic position, so that the control target point setting link and the local coordinate origin established link to form a basic position Basic posture forming means for driving and controlling the movable joint to an ideal joint position ;
Basic posture driving torque acquisition means for acquiring the driving torque of the movable joint when the basic posture is formed;
Driving torque generation that causes the movable joint to generate the driving torque acquired by the driving torque acquisition means in the basic posture in a state where the control target point setting link and the local coordinate origin setting link are fixed to the basic posture fixing device. Means,
The movable joint when the driving torque acquired by the basic posture driving torque acquisition means is generated in a state where the control target point setting link and the local coordinate origin setting link are fixed to the basic posture fixing device. An ideal joint position setting means for setting a current joint position to an ideal joint position for forming the basic posture;
The control target point when the driving means is driven and controlled so that the movable joint is at the ideal joint position in a state where the control target point setting link and the local coordinate origin setting link are released from the basic posture fixing device. A real basic posture acquisition means for acquiring the setting link and the posture of the local coordinate origin setting link as a real basic posture on a machine model;
Until the error between the actual basic posture and the basic posture becomes a predetermined allowable value or less, the basic posture forming means, the basic posture driving torque obtaining means, the driving torque generating means, the ideal joint position setting means, and , the real basic posture acquisition means repeatedly by the processing executed when the error between the real reference posture is equal to or less than a predetermined allowable value is set as an ideal joint positions to achieve the ideal reference position,
A robot apparatus characterized by that. In a robot apparatus having at least a waist, a foot, an arm, a head, and a plurality of movable joints,
Driving means for driving each of the movable joints;
Drive control means for controlling either the joint position or torque in the movable joint;
Joint position acquisition means for acquiring a joint position in the movable joint;
Torque acquisition means for acquiring drive torque in the movable joint;
Posture acquisition means for acquiring postures of the waist, the foot, the arm, and the head;
A basic posture management means for managing a basic posture of the waist, the foot, the arm, and the head formed by the movable joint becoming a predetermined joint position;
The basic posture management means includes
The waist, the foot, the arm, and the head form a basic posture without being attached to the basic posture fixing device that fixes the waist, the foot, the arm, and the head to the basic posture. Basic posture forming means for driving and controlling the movable joint to an ideal joint position ,
Basic posture driving torque acquisition means for acquiring the driving torque of the movable joint when the basic posture is formed;
Drive torque that causes the movable joint to generate the drive torque acquired by the drive torque acquisition means in the basic posture in a state where the waist, the foot, the arm, and the head are fixed to the basic posture fixing device. Generating means;
The movable joint when the driving torque acquired by the basic posture driving torque acquisition means is generated in a state where the waist, the foot, the arm, and the head are fixed to the basic posture fixing device. Ideal joint position setting means for setting the current joint position to an ideal joint position for forming the basic posture;
The waist when the drive means is driven and controlled so that the movable joint is in the ideal joint position in a state where the waist, the foot, the arm, and the head are released from the basic posture fixing device, Real basic posture acquisition means for acquiring the posture of the foot, the arm, and the head as a real basic posture on a machine model,
Until the error between the actual basic posture and the basic posture becomes a predetermined allowable value or less, the basic posture forming means, the basic posture driving torque obtaining means, the driving torque generating means, the ideal joint position setting means, and , the real basic posture acquisition means repeatedly by the processing executed when the error between the real reference posture is equal to or less than a predetermined allowable value is set as an ideal joint positions to achieve the ideal reference position,
A robot apparatus characterized by that. When the driving torque of the movable joint at the ideal joint position becomes zero, the ideal joint position setting means sets the midpoint of the joint position when the driving torque is shaken by a predetermined value in each direction as the ideal joint position. Set,
The robot apparatus according to claim 1, wherein the robot apparatus is characterized. The robot apparatus having one or more control target points, a control target point setting link for setting a control target point, a local coordinate origin, a local coordinate origin setting link for setting a local coordinate origin, and a plurality of movable joints In the control method of the robot apparatus for managing the basic posture of the control target point setting link and the local coordinate origin setting link,
In a state where the control target point setting link and the local coordinate origin setting link are not attached to the basic posture fixing device for fixing the control target point setting link and the local coordinate origin setting link so that the control target point setting link and the local coordinate origin setting link are in a basic posture. A basic posture forming step for driving and controlling the movable joint to an ideal joint position so that the setting link and the local coordinate origin setting link form a basic posture;
A basic posture driving torque acquisition step of acquiring the driving torque of the movable joint when the basic posture is formed;
Drive torque generation that causes the movable joint to generate the drive torque acquired in the basic posture drive torque acquisition step in a state where the control target point setting link and the local coordinate origin setting link are fixed to the basic posture fixing device. Steps,
In a state where the control target point setting link and the local coordinate origin setting link are fixed to the basic posture fixing device, the movable joint when the driving torque acquired in the basic posture driving torque acquisition step is generated is generated. An ideal joint position setting step for setting the current joint position to an ideal joint position for forming the basic posture;
The control target point setting link when the movable joint is controlled to be the ideal joint position in a state where the control target point setting link and the local coordinate origin setting link are released from the basic posture fixing device, and A real basic posture acquisition step of acquiring the posture of the local coordinate origin setting link as a real basic posture on the machine model;
Until the error between the actual basic posture and the basic posture becomes a predetermined allowable value or less, the basic posture forming step, the basic posture driving torque acquisition step, the driving torque generation step, the ideal joint position setting step, and , Repeatedly executing each process of the actual basic posture acquisition step, and setting an ideal joint position that realizes the ideal basic posture when an error from the actual basic posture is a predetermined allowable value or less,
A method for controlling a robot apparatus, comprising: In a control method of a robot apparatus for managing a basic posture of a robot apparatus having at least a waist, a foot, an arm, a head, and a plurality of movable joints,
In a state where the waist, the foot, the arm, and the head are not attached to the basic posture fixing device that fixes the waist, the foot, the arm, and the head so that the head is in the basic posture. A basic posture forming step of driving and controlling the movable joint to an ideal joint position so that the waist, the foot, the arm, and the head form a basic posture;
A basic posture driving torque acquisition step of acquiring the driving torque of the movable joint when the basic posture is formed;
Driving torque that causes the movable joint to generate the driving torque acquired in the driving torque acquisition step in the basic posture in a state where the waist, the foot, the arm, and the head are fixed to the basic posture fixing device. Generation step,
The movable joint when the driving torque acquired in the basic posture driving torque acquisition step is generated in a state where the waist, the foot, the arm, and the head are fixed to the basic posture fixing device. An ideal joint position setting step for setting the current joint position to an ideal joint position for forming the basic posture;
The waist portion, the foot portion, when the drive control is performed so that the movable joint is in the ideal joint position in a state where the waist portion, the foot portion, the arm portion, and the head portion are released from the basic posture fixing device. A real basic posture acquisition step of acquiring the posture of the arm and the head as a real basic posture on a machine model;
Until the error between the actual basic posture and the basic posture becomes a predetermined allowable value or less, the basic posture forming step, the basic posture driving torque acquisition step, the driving torque generation step, the ideal joint position setting step, and , Repeatedly executing each process of the actual basic posture acquisition step, and setting an ideal joint position that realizes the ideal basic posture when an error from the actual basic posture is a predetermined allowable value or less,
A method for controlling a robot apparatus, comprising: The robot apparatus having one or more control target points, a control target point setting link for setting a control target point, a local coordinate origin, a local coordinate origin setting link for setting a local coordinate origin, and a plurality of movable joints In the basic posture setting method of the robot apparatus for managing the basic posture of the control target point setting link and the local coordinate origin setting link,
In a state where the control target point setting link and the local coordinate origin setting link are not attached to the basic posture fixing device that fixes the control target point setting link and the local coordinate origin setting link so that the basic coordinate origin setting link is the basic posture. A basic posture forming step for driving and controlling the movable joint to an ideal joint position so that the point setting link and the local coordinate origin setting link form a basic posture;
A basic posture driving torque acquisition step of acquiring the driving torque of the movable joint when the basic posture is formed;
Drive torque generation that causes the movable joint to generate the drive torque acquired in the basic posture drive torque acquisition step in a state where the control target point setting link and the local coordinate origin setting link are fixed to the basic posture fixing device. Steps,
In a state where the control target point setting link and the local coordinate origin setting link are fixed to the basic posture fixing device, the movable joint when the driving torque acquired in the basic posture driving torque acquisition step is generated is generated. An ideal joint position setting step for setting the current joint position to an ideal joint position for forming the basic posture;
The control target point setting link when the movable joint is controlled to be the ideal joint position in a state where the control target point setting link and the local coordinate origin setting link are released from the basic posture fixing device, and A real basic posture acquisition step of acquiring the posture of the local coordinate origin setting link as a real basic posture on the machine model;
Until the error between the actual basic posture and the basic posture becomes a predetermined allowable value or less, the basic posture forming step, the basic posture driving torque acquisition step, the driving torque generation step, the ideal joint position setting step, and The actual basic posture acquisition step is repeatedly executed, and when the error from the actual basic posture becomes a predetermined allowable value or less, the ideal joint position that realizes the ideal basic posture is set as the basic posture of the robot apparatus. Set,
A basic posture setting method for a robot apparatus. In the basic posture setting method of the robot apparatus for managing the basic posture of the robot apparatus having at least the waist, legs, arms, head, and a plurality of movable joints,
In a state where the waist, the foot, the arm, and the head are not attached to the basic posture fixing device that fixes the waist, the foot, the arm, and the head so that the head is in the basic posture. A basic posture forming step of driving and controlling the movable joint to an ideal joint position so that the waist, the foot, the arm, and the head form a basic posture;
A basic posture driving torque acquisition step of acquiring the driving torque of the movable joint when the basic posture is formed;
Driving torque that causes the movable joint to generate the driving torque acquired in the driving torque acquisition step in the basic posture in a state where the waist, the foot, the arm, and the head are fixed to the basic posture fixing device. Generation step,
The movable joint when the driving torque acquired in the basic posture driving torque acquisition step is generated in a state where the waist, the foot, the arm, and the head are fixed to the basic posture fixing device. An ideal joint position setting step for setting the current joint position to an ideal joint position for forming the basic posture;
The waist portion, the foot portion, when the drive control is performed so that the movable joint is in the ideal joint position in a state where the waist portion, the foot portion, the arm portion, and the head portion are released from the basic posture fixing device. A real basic posture acquisition step of acquiring the posture of the arm and the head as a real basic posture on a machine model;
Until the error between the actual basic posture and the basic posture becomes a predetermined allowable value or less, the basic posture forming step, the basic posture driving torque acquisition step, the driving torque generation step, the ideal joint position setting step, and , Repeatedly executing each process of the actual basic posture acquisition step, and setting an ideal joint position that realizes the ideal basic posture when an error from the actual basic posture is a predetermined allowable value or less,
A basic posture setting method for a robot apparatus.

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