JPH10277969A - Control device of leg type moving robot - Google Patents

Abstract

PROBLEM TO BE SOLVED: To appropriately control the actual floor reaction by detecting the actual floor reaction to calculate the moment around the center point, determining the amount of rotation to correct the target position and/or posture so that the position and/or posture of the leg part is rotated, and to displace the joint of a robot. SOLUTION: A two-foot walking robot 1 is provided with a joint on a leg part link 2. A six-axis force sensor 44 is mounted on a foot joint, the three- direction components of the force and the moment are measured, and presence/ absence of landing of a foot part and the floor reaction are detected. An inclination sensor 60 is installed on an upper body 24 to detect the inclination and the angular velocity. A rotary encoder to detect an amount of the rotation is provided on an electric motor for a joint. First and second arithmetic units are provided in a control unit 26, and the first arithmetic unit calculates the angular displacement command of the joint, and feeds it to a RAM. The second arithmetic unit reads the measured value to detect the command from the RAM, calculates the control value, and outputs it to the electric motor. The floor reaction can be appropriately controlled without generating the interference.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a legged mobile robot, and more particularly, to a posture control device for the legged mobile robot. The present invention relates to an apparatus for appropriately controlling a floor reaction force acting on a mobile robot.

[0002]

2. Description of the Related Art The most basic and simple legged mobile robot,
More specifically, the control device of the bipedal walking robot includes a target motion pattern generation device and a joint drive control device. The target motion pattern generation device generates at least a target motion pattern. Typically, the gait movement pattern is then calculated by kinetic calculations, ie, Z, which is determined by solving the Euler-Newton equation.
The MP trajectory is generated so as to be a desired trajectory set in advance. The joint drive control device controls each joint so as to follow a displacement command of each joint generated by the gait generating device.

Here, ZMP (Zero Moment Point) is
The moment around the point of action on the floor surface of the resultant force of the inertial force and gravity generated by the motion pattern is zero, excluding the component around the vertical axis.

[0004] In this device, as shown in FIG. 40, the gait generator currently generates the gait on the assumption that the gait is on a flat floor. ,
If the foot on the front side steps on an unexpected road surface, an excessive floor reaction force greater than expected on the foot is generated, and the robot tilts. In order to solve the problem, the present applicant has proposed such a control device of a bipedal legged mobile robot in, for example, Japanese Patent Application Laid-Open No. 5-305586.

In this method, the required amount of restoring moment required for restoring the body posture by detecting the body inclination is determined, and the actual total floor reaction force around the desired total floor reaction force center point (target ZMP) is determined. A moment component is detected, and each foot is controlled to move up and down so as to match the required moment of the restoration moment. The actual total floor reaction force moment is a moment generated by the resultant force of each actual foot floor reaction force around the target total floor reaction force center point (target ZMP).

[0006] The control proposed earlier (hereinafter referred to as "double-leg compliance control") will be described taking an example of a case where there is an unexpected inclination as shown in FIG. For explanation, each foot is numbered as shown in FIG. Although the gait generator assumed that the gait was generated on the assumption of a flat floor, as shown in FIG. 40, the first foot was not expected at the beginning of the two-leg support period. Step 1
Assume that this is the moment when a foot floor reaction force greater than the desired value for the foot occurs. It is also assumed that the robot is still in a desirable posture (body tilt 0) at this moment.

In the proposed control device, the actual total floor reaction force moment around the target total floor reaction force center point (target ZMP) is detected. At this moment, this actual total floor reaction force moment is
Since the vertical component of the first foot floor reaction force is excessive, it acts in a direction to cause the robot to fall later.

In order to reduce this moment to zero, as shown in FIG. 41, a virtual floor AA 'is assumed, and the virtual floor is moved to the desired total floor height while each foot is placed on the virtual floor. The position of each foot is moved to a position rotated by an appropriate angle Δθ around the force center point (target ZMP).

As a result, the vertical component of the first foot floor reaction force decreases, and the vertical component of the second foot floor reaction force increases. As a result, the actual total floor reaction force moment around the desired total floor reaction force center point (target ZMP) becomes substantially zero. That is, even if there is an unexpected slope on the floor, the two-leg compliance control works normally, so that the robot can continue walking without falling down.

[0010] However, since the actual floor reaction force of each foot cannot be controlled during the period of supporting both legs by using the proposed technique alone, unexpected local inclination and unevenness in the floor shape around the foot contact point of the foot is not possible. In some cases, the ground contact of the foot is reduced and the spin is easily performed, or a sudden change in posture causes a fall.

For example, as shown in FIG. 42, if the toes of the first foot step on unexpected projections (steps) during the period of supporting both legs, the toes of the first foot suddenly increase during the period of supporting both legs. Since the floor is gradually falling, the floor is strongly kicked with a toe and the vertical component of the first foot floor reaction force increases rapidly.
As a result, an actual total floor reaction force moment is suddenly generated around the target total floor reaction force center point (target ZMP), and in the worst case, the vehicle falls down in time to restore the posture by the two-leg compliance.

Even if the player does not fall down during the two-leg support period, when the second foot is separated from the floor immediately thereafter, the desired total floor reaction force center point (target ZMP) is at the heel of the first foot. Nevertheless, because the heel is floating, the actual total floor reaction force center point is at the toe, so the actual total floor reaction force that tries to defeat the robot around the target total floor reaction force central point (target ZMP) later A moment is generated and it falls.

That is, this two-leg compliance control is
It can respond to global inclinations and undulations that change slowly over long distances, but cannot respond to local inclinations and steps at the landing point of the foot.

In addition to the above-described two-leg compliance control, the present applicant has disclosed in Japanese Patent Application Laid-Open No. 5-305584, for example, that a biped walking robot is provided with a landing impact absorbing mechanism having spring characteristics such as rubber at the ankle. Proposes an ankle compliance control for detecting an actual foot floor reaction force moment component around each ankle and rotating each ankle to make it zero.

In order to solve the above problems, in addition to the two-leg compliance control, Japanese Patent Application Laid-Open No. HEI 5-30558.
The technique proposed in Japanese Patent Publication No. 4 (hereinafter referred to as "ankle compliance control") can be used in combination.

As a result, as shown in FIG. 43, the first ankle is rotated in a direction to cancel the unexpected first foot floor reaction force moment by the ankle compliance control, as shown in FIG.
The heel can be grounded to the floor. Therefore, the robot does not fall down as described above even in the subsequent one-leg supporting period.

[0017]

However, simply using the two-leg compliance control and the ankle compliance control simply interferes with each other, and the actual total floor reaction force and the actual foot floor reaction force are desirable. There was a problem of deviation from the value or oscillation.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-described disadvantages, and a leg type capable of easily and appropriately controlling the actual floor reaction force acting on a leg type mobile robot without causing interference. A control device for a mobile robot is provided.

A second object of the present invention is to provide a foot-type system that is not significantly affected by unexpected floor shape changes including local irregularities and slopes as well as global undulations and slopes. An object of the present invention is to provide a control device for a legged mobile robot that can appropriately control a floor reaction force acting on the mobile robot.

A third object of the present invention is to provide a legged mobile robot capable of facilitating posture stabilization control of a legged mobile robot by appropriately controlling a floor reaction force acting on the legged mobile robot. To provide a control device.

A fourth object of the present invention is to control a legged mobile robot capable of reducing a landing impact received by the legged mobile robot by appropriately controlling a floor reaction force acting on the legged mobile robot. It is to provide a device.

Furthermore, the bipedal walking robot walks by swinging the free leg, thereby generating an inertial moment about the vertical (gravity) axis of the robot, and the upper body rotationally vibrates around the vertical axis, which causes the robot to vibrate. The vertical component of the actual floor reaction force moment of each foot vibrates. When the amplitude of the vibration becomes excessive, the peak value of the actual foot floor reaction force moment exceeds the limit of friction, and at that moment, the sole slides and the robot spins. If the spin is large, the person may lose posture stability and fall. Therefore, it is desirable to reduce such vibration in addition to the control described above.

Accordingly, a fifth object of the present invention is to appropriately control a floor reaction force acting on a legged mobile robot,
It is an object of the present invention to provide a control device for a legged mobile robot that reduces vibration of a vertical component of a floor reaction force moment.

[0024] A sixth object of the present invention is to further improve the ground contact of the legged mobile robot by appropriately controlling the floor reaction force acting on the legged mobile robot, and to prevent slippage during walking and the aforementioned spin. An object of the present invention is to provide a control device for a legged mobile robot, which can prevent the occurrence of the problem.

A seventh object of the present invention is to control a legged mobile robot capable of reducing the load on the actuator of the legged mobile robot by appropriately controlling the floor reaction force acting on the legged mobile robot. It is to provide a device.

[0026]

In order to achieve the above object, according to the present invention, at least a base is connected to the base via a first joint, and a first end is connected to the base. In a control device for a legged mobile robot including a plurality of legs having legs connected via two joints, a motion pattern including at least a target position and a posture of the legs of the robot; Gait generating means for generating a gait of the robot including at least a target pattern of a total floor reaction force acting on the foot, wherein the total floor reaction force of the generated gait is distributed to each of the feet Target foot floor reaction force center point determining means for determining a desired foot floor reaction force center point as an action center point on the part, actual floor reaction force detecting means for detecting an actual floor reaction force acting on the foot, The detected actual floor reaction force is calculated as described above. Foot rotation determining means for calculating a moment acting around the foot reaction force center point, and determining a rotation amount for rotating the foot based on at least the calculated moment; and the determined foot. Foot position / posture correction means for correcting the target position and / or posture so that the position and / or posture of the foot is rotated based on the amount of rotation, and the corrected position / posture of the foot
A joint displacing means for displacing the first and second joints of the robot based on the posture is provided.

In this claim and the following claims, "target pattern of total floor reaction force" means a target pattern relating to the total floor reaction force, including at least the locus of the center point of the total floor reaction force. The “total floor reaction force” specifically means the resultant force of the floor reaction forces acting on the robot via the leg tip.
Note that “foot” specifically means a foot similar to the human foot of a bipedal walking robot, but includes the tip of the leg of three or more legged mobile robots, and It is used to mean that it mainly includes nails that are different from the feet.

According to the second aspect of the present invention, at least a base and a foot connected to the base via a first joint and connected to a distal end of the base via a second joint are provided. In the control device for a legged mobile robot having a plurality of legs provided, at least a movement pattern including a target position and a posture of the foot of the robot and a target pattern of a total floor reaction force acting on the robot are at least set. Gait generating means for generating a gait of the robot, wherein a desired foot floor reaction acting as a central point of action on the foot when the total floor reaction force of the generated gait is distributed to each of the feet; Target foot floor reaction force center point determining means for determining a force center point, actual floor reaction force detecting means for detecting an actual floor reaction force acting on the foot, and at least based on the detected actual floor reaction force. Determine the amount of rotation to rotate the foot Means for determining the amount of rotation of the foot, based on the determined amount of rotation of the foot, so that the position and / or posture of the foot rotates around the determined target foot floor reaction force center point or its vicinity. A foot position / posture correcting means for correcting the target position and / or posture;
And a joint displacement means for displacing the first and second joints of the robot based on the corrected position and posture of the foot.

According to a third aspect of the present invention, the foot position / posture correcting means determines the position and / or orientation of the foot based on the determined foot rotation amount by the determined target foot. The target position and / or posture is modified so as to rotate around or near the center point of the floor reaction force.

According to a fourth aspect of the present invention, a floor reaction force acting on the foot is calculated from a total floor reaction force moment actually acting on the robot or a total floor reaction force moment actually acting on the robot. Calculating any one of the moments obtained by subtracting the moment, and a foot moving amount determining means for determining a moving amount for moving the foot according to at least the calculated moment; The posture correcting means is configured to correct the position and / or posture of the foot based on the determined rotation amount of the foot and the determined movement amount.

According to a fifth aspect of the present invention, a posture stabilization compensation total floor reaction force moment to be added to the target pattern of the total floor reaction force is obtained, and the foot rotation amount determining means and / or the foot movement amount are determined. The determining means is configured to determine a rotation amount and / or a movement amount of the foot based on at least the detected actual floor reaction force and the determined posture stabilization compensation total floor reaction force moment.

According to a sixth aspect of the present invention, the posture stabilization compensation total floor reaction force moment is obtained based on at least a tilt deviation of the robot.

According to a seventh aspect of the present invention, the posture stabilization compensation total floor reaction force moment is obtained based on at least the yaw rate of the robot.

According to an eighth aspect of the present invention, the posture stabilization compensation total floor reaction force moment is obtained based on at least a deviation from the target path of the robot.

According to a ninth aspect of the present invention, a predetermined component of the attitude stabilization compensation total floor reaction force moment is set to zero or near zero.

In the tenth aspect, the position of the foot portion
The posture correcting means is configured to further correct the target position and / or the posture based on the posture deviation of the robot.

In the eleventh aspect, the foot rotation amount determining means and / or the foot movement amount determining means may be configured such that the posture stabilization compensation total floor reaction force moment is equal to each of the plurality of legs. The amount of rotation and / or the amount of movement of the foot is determined so as to be distributed.

In a twelfth aspect, at least the base is connected to the base via the first joint,
In a control device for a legged mobile robot comprising a plurality of legs each having a leg connected to a distal end thereof via a second joint, a motion pattern including at least a target position and a posture of the leg of the robot. Gait generating means for generating a gait of the robot comprising a target trajectory pattern of a total floor reaction force acting on the robot, posture stabilization for calculating a compensated total floor reaction force for stabilizing the posture of the robot Compensated total floor reaction force calculating means, foot actual floor reaction force detecting means for detecting an actual floor reaction force acting on the foot, a floor for distributing the total floor reaction force of the target gait and the compensated total floor reaction force. Reaction force distribution means, based on the distributed floor reaction force of the desired gait, the compensated floor reaction force, and the detected actual foot reaction force of the foot, and
Or a correcting means for correcting the posture, and a first position of the robot based on the corrected target foot position and posture.
And joint displacement control means for controlling the displacement of the second joint.

According to a thirteenth aspect, the correction means is configured to further correct the position and / or posture of the foot of the desired gait based on the posture deviation of the robot.

[0040]

According to the present invention, the floor reaction force acting on the legged mobile robot can be easily and appropriately controlled without causing interference. In other words, even if control similar to the combination of the previously proposed two-leg compliance control and ankle compliance control is performed, there is no control interference, and the actual total floor reaction force and the actual foot floor reaction force deviate from desired values or oscillate. Never do.

That is, in addition to the global swell and inclination,
Even if there is an unexpected floor shape change including local unevenness or inclination, the floor reaction force acting on the legged mobile robot can be appropriately controlled without being greatly affected by the unexpected change.

In addition, the posture stabilization control of the legged mobile robot can be easily realized, the landing impact received by the legged mobile robot can be reduced, the grounding property of the legged mobile robot can be improved, and the slip during walking can be improved. And spin can be prevented. Further, the load on the actuator of the legged mobile robot can be reduced.

According to the second aspect, the same operation and effect as those of the first aspect can be obtained.

According to the third aspect, the same operation and effect as those of the first aspect can be obtained, and the floor reaction force can be more appropriately controlled.

According to the fourth aspect, the same function and effect as those of the first aspect can be obtained, and the total floor reaction force, which is particularly important for attitude control, can be more appropriately controlled.

According to the fifth aspect, the same function and effect as those of the first aspect can be obtained, and the posture stabilizing ability can be improved.

According to the sixth aspect, the same operation and effect as described above can be obtained, and the posture stabilizing ability can be further improved.

According to the seventh aspect, the same operation and effect as described above can be obtained, the spin or slip of the robot can be prevented, and the posture stabilizing ability can be further improved. Therefore, even when walking on a road surface having a low coefficient of friction, spin or slip can be effectively prevented, and walking can be continued in a stable posture.

According to the eighth aspect, the same operation and effect as described above can be obtained, and walking can be continued in a stable posture along the target route.

According to the ninth aspect, the same operation and effect as described above can be obtained, and the spin or slip of the robot can be prevented to a considerable extent without detecting the yaw rate. In that sense, the posture stabilizing ability can be further improved.

According to the tenth aspect, the same operation and effect as described above can be obtained, and the actual floor reaction force acting on the robot can be controlled with higher accuracy.

According to the eleventh aspect, the same operation and effect as described above can be obtained, the load of the plurality of legs can be appropriately distributed, and the friction distribution with the floor surface is locally distributed. Does not have an excessive effect on Therefore, the grounding performance can be further improved, and the spin or the slip can be further avoided.

According to the twelfth aspect, the same function and effect as those of the first aspect can be obtained, and the correction amount of the foot can be more appropriately distributed. Greater restoring force and higher groundability can be obtained.

According to the thirteenth aspect, the same function and effect as those of the twelfth aspect can be obtained, and the actual floor reaction force acting on the robot can be more accurately controlled.

[0055]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A control device for a legged mobile robot according to the present invention will be described below with reference to the accompanying drawings. still,
A bipedal walking robot is taken as an example of a legged mobile robot.

FIG. 1 is a schematic diagram showing the entire control device of the legged mobile robot.

As shown, the bipedal walking robot 1 has six joints on each of the left and right leg links 2 (for convenience of understanding, each joint is shown by an electric motor that drives it). The six joints are, in order from the top, joints 10R and 10L for turning the crotch (waist) (R is the right side and L is the left side).
The same shall apply hereinafter), joints 12R and 12L in the roll direction (around the Y axis) of the crotch (lumbar region), joints 14R and 14L in the same pitch direction (around the X axis), and joints 16R and 1 in the roll direction of the knee.
6L, the joints 18R and 18L in the roll direction of the ankle, and the joints 20R and 20L in the same pitch direction.

At the lower portions of the joints 18R (L), 20R (L), feet (foot portions) 22R, 22L are attached, and at the top, an upper body (base) 24 is provided. A control unit 26 (described later) including a microcomputer is stored. In the above, the hip joints (or hip joints) are joints 10R (L), 12R (L), and 14R (L).
From, the ankle joint (ankle joint) is joint 18R (L), 20R
(L). The hip joint and the knee joint are thigh links 28R and 28L, and the knee joint and the ankle joint are the lower leg link 3
Connected at 0R, 30L.

With the above configuration, the leg link 2 is given six degrees of freedom for each of the left and right feet, and by driving these 6 * 2 = 12 joints at an appropriate angle during walking, A desired motion can be given to the whole, and the user can walk in a three-dimensional space arbitrarily (in this specification, “*” indicates multiplication as an operation on a scalar, and an outer product as an operation on a vector).

The position of the body and the speed thereof, which will be described later in this specification, are determined at predetermined positions of the body 24, specifically, the body 2
4 means the position of the representative point such as the position of the center of gravity and the moving speed thereof.

As shown in FIG. 1, a known six-axis force sensor 44 is attached below the ankle joint, and three-directional components Fx and F of the force.
y, Fz and the three-way components Mx, My, Mz of the moment are measured, and the presence or absence of landing on the foot and the floor reaction force (ground contact load)
And so on. An inclination sensor 60 is provided on the body 24, and detects an inclination with respect to the Z axis (vertical direction (gravity direction)) and its angular velocity. The electric motor of each joint is provided with a rotary encoder for detecting the amount of rotation.

As shown in FIG. 2, a spring mechanism 32 is provided above the foot 22R (L), and a sole elastic body 34 made of rubber or the like is attached to the sole. Spring mechanism 3
Specifically, 2 is a rectangular guide member attached to the foot 22R (L) and attached to the ankle joint 18R (L) and the 6-axis force sensor 44 side, and the guide member is connected to the guide member via an elastic material. And a piston-like member that is stored so as to be finely movable.

The foot 22R (L) indicated by a solid line in the figure
Indicates a state when no floor reaction force is received. When the floor reaction force is received, the spring mechanism 32 and the sole elastic body 34 bend, and the foot moves to the position / posture indicated by the dotted line in the figure. This structure is important not only to alleviate landing impact but also to enhance controllability. The details are described in the above-mentioned Japanese Patent Application Laid-Open No. 5-305584, and the detailed description is omitted.

Further, although not shown in FIG. 1, a joystick 62 is provided at an appropriate position of the bipedal walking robot 1 so that the robot moving straight ahead can be turned from the outside as necessary. It is configured to allow you to enter requests.

FIG. 3 is a block diagram showing details of the control unit 26, which is constituted by a microcomputer. The output of the tilt sensor 60 and the like is converted into a digital value by the A / D converter 70, and the output
Via the RAM 74. The output of an encoder disposed adjacent to each electric motor is input to the RAM 74 via the counter 76.

In the control unit, a first unit comprising a CPU,
Second computing devices 80 and 82 are provided. The first computing device 80 calculates a joint angle displacement command based on the gait stored in the ROM 84 as described later,
Send it to AM74. The second arithmetic unit 82 is a RAM
The command and the detected actual value are read out from 74 and the control value necessary for driving each joint is calculated, and the D / A converter 86
And output to an electric motor that drives each joint via a servo amplifier.

Here, the terms used in this specification and the drawings are defined. (Note that terms not defined are defined in an application (Japanese Patent Application No. 8-214261) proposed by the present applicant separately from the above-mentioned technology. According to the definition used).

The "gait" is different from the general definition in robotics and is used to mean a combination of a target motion pattern and a floor reaction force pattern. However, the floor reaction force pattern may be partial information such as “only ZMP trajectory”. Therefore, the term “gait generation device” is not used for a device that outputs only a target motion pattern and does not output information about a floor reaction force pattern.

Each leg is given a serial number. The floor reaction force acting on the n-th leg is referred to as the n-th foot floor reaction force (n: 1 or 2; the same applies hereinafter). The sum of the floor reaction forces acting on all legs is called the total floor reaction force (generally called floor reaction force in robotics, but here the "total floor reaction force" ).

The foot floor reaction force is represented by the point of action, the force applied thereto, and the moment of the force. There are infinite combinations of expressions for the same foot floor reaction force. Among them,
There is a notation in which the moment component excluding the component around the vertical axis is 0 and the action point is on the floor surface. The point of action in this expression is herein referred to as the foot floor reaction force center point (referred to as the "ground contact pressure center point" in Japanese Patent Application Laid-Open No. Hei 6-79657, which is separately proposed by the present applicant).

Similarly, the total floor reaction force is represented by the point of action, the force applied thereto and the moment of the force, and there are infinite combinations of expressions for the same total floor reaction force. Among them, there is a representation in which the moment component excluding the component around the vertical axis is 0 and the action point is on the floor surface. The point of action in this expression is herein referred to as the total floor reaction force center point.

The target value of the total floor reaction force is called a target total floor reaction force.
The desired total floor reaction force is generally a total floor reaction force that dynamically balances with the desired movement pattern. Therefore, normally, the desired total floor reaction force center point coincides with the desired ZMP.

As mentioned earlier, the target ZMP (Ze
ro Moment Point) is defined as follows. That is, if the resultant force of the inertial force and gravity generated by the target motion pattern is dynamically obtained, and the moment acting on a certain point on the floor surface is 0 except for the component around the vertical axis,
This point is called a target ZMP (Zero Moment Point). The target ZMP is uniquely obtained as long as the vertical force component of the resultant force is not zero. In the following description, the term “target ZMP” may be used for easy understanding, but strictly speaking, there are many places that should be called the target floor reaction force center point.

The target value of each foot floor reaction force is referred to as a desired foot floor reaction force. However, unlike the desired total floor reaction force, the desired foot floor reaction force is not uniquely determined even if the desired exercise pattern is determined. The total floor reaction force acting on the actual robot is called the actual total floor reaction force. Each foot floor reaction force acting on the actual robot is called an actual foot floor reaction force.

Here, if the subject of the present invention is re-explained, it is difficult to obtain good posture stability by the previously proposed two-leg compliance control with respect to local inclination and step, and the inconvenience is caused by ankle compliance. Although it can be eliminated by using the control, the simple use of the two causes interference, and the actual total floor reaction force and the actual foot floor reaction force deviate from desired values or oscillate.

The problem will be described with reference to the situation shown in FIG. 40. The first foot receives an unexpectedly large floor reaction force on the heel, so that an excessively large actual foot around the first ankle. A flat floor reaction force moment occurs. In the ankle compliance control, the first ankle is moved as shown in FIG.
Rotate as shown.

However, the rotation of the ankle causes the first
Since the heel position of the foot is raised, the vertical component of the first foot floor reaction force is reduced. As a result, the actual total floor reaction force moment around the target total floor reaction force center point (target ZMP) changes.
This means that the actual total floor reaction force moment, which is a control amount of the two-leg compliance control, is interfered with by the ankle compliance control.

Therefore, if the two-leg compliance control is operated in the same manner as without the ankle compliance control without considering the interference caused by the ankle compliance control, the actual total floor reaction force around the desired total floor reaction force center point (target ZMP) is obtained. The moment deviates from zero, and vibration or oscillation occurs due to interference.

One method of preventing this is to determine the amount of interference between the two-leg compliance control and the ankle compliance control, and add an operation amount that cancels this to prevent the interference. In the middle, the attitude changes every moment, and the interference relationship also changes every moment. Therefore, it is extremely difficult to avoid the interference by this method.

Further, in the situation shown in FIG. 43, the floor with which the first foot is in contact is more uphill than the expected floor, so that the first foot should be raised more than the target gait. is there. Nevertheless, the fact that the toes are lowered by the ankle compliance control means that the ankle compliance control is not working properly.

As described above, the ankle compliance control is effective for the local floor inclination or step at the landing point of the foot, but has an adverse effect on the inclination or swell that changes slowly over a long distance. There are cases.

Therefore, in the apparatus according to the embodiment, the floor reaction force acting on the legged mobile robot, more specifically, the actual total floor reaction force moment around the target total floor reaction force center point and the target The actual foot floor reaction force moment around the foot floor reaction force center point can be controlled easily and appropriately.

In addition, even if there is an unexpected floor shape change including local irregularities and slopes as well as global undulations and slopes, the robot can walk in a stable posture without being greatly affected by the change. It was made to continue.

FIG. 4 shows a control device of the legged mobile robot according to this embodiment (mainly the first arithmetic unit 80 in FIG. 3).
FIG. 3 is a block diagram functionally showing the configuration and operation of (equivalent to). Hereinafter, the overall configuration of this device will be outlined with reference to FIG.

This device includes a gait generator, and the gait generator generates and outputs a desired gait. The desired gait is, as defined above, a desired exercise pattern and a desired floor reaction force pattern, more specifically, a desired body position / posture trajectory, a desired foot position /
It consists of an attitude trajectory, a desired total floor reaction force center point (desired ZMP) trajectory, and a desired total floor reaction force trajectory. The desired floor reaction force pattern is
Thus, the target total floor reaction force center point locus is included (if the mechanism deformation compensation described later is not performed, the target total floor reaction force center point locus alone may be used as the target floor reaction force pattern).

In this embodiment, the desired total floor reaction force output by the gait generator is a total floor reaction force that dynamically balances with the desired movement pattern. Therefore, the desired total floor reaction force center point coincides with the desired ZMP.

FIG. 5 shows an example of a target movement pattern when the robot 1 walks on flat ground. Target Z corresponding to this
FIG. 6 shows the trajectory of the MP orbit on the floor, and FIG. 7 shows a time chart. The foot remaining in contact with the floor during this gait is referred to as a first foot, and the other foot is referred to as a second foot.
The details of the gait generator are described in the previously proposed Japanese Patent Application No. 8-214.
No. 261, and further description is omitted.

Returning to the description of FIG. 4, this device is provided with a desired floor reaction force distributor, and the desired floor reaction force distributor determines a desired total floor reaction force center point (a desired ZMP) and a desired foot position / posture. The main input is to determine and output the desired foot floor reaction force center point. Actually, the gait generator uses the gait parameters (for example, the time of the two-leg support period, the target landing position of the swing leg foot, etc.) and the time and time of the gait (for example, the current time is Information such as 0.1 seconds from the beginning) is also imported as needed.

For a gait as shown in FIG. 5, the desired floor reaction force distributor sets such that each desired foot floor reaction force center point satisfies the following conditions. Condition 1) The desired foot floor reaction force center point trajectory is continuous. Condition 2) In the two-leg support period, the target first foot floor reaction force center point is on the heel, and the target second foot floor reaction force center point is on the toes. Condition 3) At this time, the desired first foot floor reaction force center point and the desired second floor
The target total floor reaction force center point exists on a line connecting the foot floor reaction force center points. Condition 4) In the one-leg support period, the target first foot floor reaction force center point coincides with the target total floor reaction force center point. Condition 5) During the one-leg supporting period, the desired second foot floor reaction force central point moves from the toe to the heel.

FIG. 8 is a time chart of the desired first foot floor reaction force center point trajectory satisfying these conditions, and FIG. 9 is a time chart of the desired second foot floor reaction force center point trajectory.
In this figure, the vertical projection point from the ankle (joint 18, 20R (L)) to the foot 22R (L) is set as the origin, and as shown in FIG. The left direction is the positive direction of the Y axis.

The desired floor reaction force distributor further determines, and outputs the desired foot floor reaction force, though it is incidental. The desired foot floor reaction force is necessary for compensating deflection of the spring mechanism 32 and the like.

If the desired floor reaction force corresponding to the desired foot floor reaction force center point set as described above is determined using the following equation, the resultant force of the desired foot floor reaction force will be the desired total floor reaction force. Satisfies the condition that they must match.

Desired first foot floor reaction force = Target total floor reaction force * (Distance between desired second foot floor reaction force center point and target ZMP) / (Target first foot floor reaction force center point and desired second foot) (Distance of flat floor reaction force center point) Target second foot floor reaction force = Target total floor reaction force * (Distance between target first foot floor reaction force center point and target ZMP) / (Target first foot floor reaction force center point) (Distance between the target 2nd foot floor reaction force center point)

Since the desired foot floor reaction force thus obtained changes continuously, it is suitable for realizing walking with less impact. The above details are described in a technique separately proposed by the present applicant (JP-A-6-79657).

Returning to the description of FIG. 4, this apparatus includes a posture stabilization control calculation unit. The posture stabilization control calculation unit estimates the state of the robot based on the sensor information of the robot, and calculates the compensation total floor reaction force. calculate. In other words, when the robot is actually walking or standing upright, even if the actual joint displacement can completely follow the target joint displacement by the displacement controller described later, the robot position / posture is not necessarily the desired position / posture. It does not become a posture.

In order to stabilize the posture of the robot for a long period of time, a force and a moment necessary for restoring the robot to a desired position and posture are obtained, and these are calculated as a desired center point of the total floor reaction force (a desired ZMP). It must be additionally generated as an action point. This additional force and moment is called the compensating total floor reaction force. The moment component of the compensating total floor reaction force is referred to as a compensating total floor reaction force moment.

It is assumed that the desired gait of the legged mobile robot receives a reaction force other than the floor reaction force from the environment, and this is called, for example, a target object reaction force. May be extended as follows. That is, the resultant of the inertial force, gravity, and the reaction force of the target object generated by the target motion pattern is dynamically obtained, and the moment acting on a certain point on the floor surface becomes zero except for the component around the vertical axis. If so, that point may be set as the target ZMP again.

If it is assumed that the robot 1 is a completely rigid body and the displacement controller allows the actual joint displacement to completely follow the target joint displacement, the deflection of the foot spring mechanism 32 and the sole elastic body 34 is assumed. Perturbation of the position and orientation of the entire robot caused by
It can be decomposed freely.

Mode 1) The desired total floor reaction force center point (the desired ZM
Mode 2) Rotation around left and right axis around target center of desired total floor reaction force (target ZMP) (ie, tilt forward and backward) Mode 3) Target whole floor Rotation (ie, spin) around the vertical axis about the reaction force center point (target ZMP) Mode 4) Forward / backward translational movement Mode 5) Right / left parallel translational oscillation Mode 6) Vertical translational oscillation

Modes 4 and 5 are generated when the spring mechanism 32 of the foot and the elastic body 34 bend by receiving a shear force in the front, rear, left and right directions. Since the spring mechanism 32 and the sole elastic body 34 are manufactured so as to have high rigidity in the shearing direction, the swing is extremely small, and there is almost no adverse effect on walking.

Of the remaining four degrees of freedom, mode 3 and mode 6 do not directly relate to the present invention. Therefore, in this embodiment and a second embodiment described later, only control for mode 1 and mode 2 is performed. I will do it. The control for the mode 1 and the mode 2 is extremely important because without this, the robot almost falls over. Note that control for mode 3 is performed in the third embodiment.

The manipulated variable for controlling the mode 1 is a moment component about the front-rear axis (X-axis) of the compensating total floor reaction force. The operation amount for controlling the mode 2 is a moment component about the left-right axis (Y-axis) of the compensating total floor reaction force. Accordingly, only the moment component in the front-rear direction and the moment component in the left-right direction need to be obtained from the components of the total floor reaction force. Other components are in this embodiment (and in the second embodiment)
Since it is not used, 0 may be used.

Note that the following definitions follow. That is, the moment component of the compensating total floor reaction force is calculated by compensating the total floor reaction force moment Md.
md (specifically, a compensated total floor reaction force moment Mdmd around the target total floor reaction force center point (target ZMP)). As shown in FIG. 5, the forward direction of the robot is the X axis, the left lateral direction is the Y axis,
A coordinate system in which the upward direction is the Z axis and the origin is a point on the floor immediately below the ankle of the first foot is referred to as a supporting leg coordinate system. Unless otherwise specified, the position, force and moment are expressed in this coordinate system. Shall be. Further, the X component of Mdmd is represented by Mdmdx,
The Y component is described as Mdmdy, and the Z component is described as Mdmdz.
The X component of the inclination deviation of the body 24 (that is, the actual body inclination-the target body inclination) θerr is described as θerrx, the Y component is θerry, and the time differential values thereof are described as (dθerrx / dt) and (dθerry / dt). I do.

Mdmdx and Mdmdy are determined by, for example, the following control law. Mdmdx =-Kthxθerrx-Kwx (dθerrx / dt) Mdmdy =-Kthyθerry-Kwy (dθerry / dt) Equation 2 where Kthx, Kthy, Kwx and Kwy are
This is the body tilt stabilization control gain.

The composite compliance operation determining section described later works to make the actual total floor reaction force coincide with the resultant force of the target total floor reaction force and the compensation total floor reaction force.

Returning to the description of FIG. 4, this device is provided with actual foot floor reaction force detectors, and the actual foot floor reaction force detectors are detected by the six-axis force sensor 44 to determine the actual foot floor reaction force (the resultant force). Detects the actual total floor reaction force). Further, based on the actual displacement (or displacement command) detected by the joint encoder, the relative position / posture of each foot with respect to the coordinate system fixed to the body is calculated, whereby the detection value of the six-axis force sensor 44 is calculated. Are converted into coordinates, and actual foot floor reaction forces expressed in a coordinate system fixed to the body are calculated, and further converted to a support leg coordinate system.

This device has a robot geometric model (inverse kinematics operation unit).
When the body position / posture and the foot position / posture are input, each joint displacement satisfying them is calculated. The degree of freedom of the joint per leg as in the robot 1 in this embodiment is 6
In the case of, each joint displacement is uniquely obtained.

In this embodiment, the equations for the solution of the inverse kinematics are obtained directly, and the displacement of each joint is obtained simply by substituting the body position / posture and the foot position / posture into the equations. That is, the robot geometric model inputs the target body position / posture and the corrected target foot position / posture trajectory (corrected target foot position / posture trajectory with mechanical deformation compensation) corrected by the composite compliance operation determination unit, From these, joint displacement commands (values) of twelve joints (10R (L) and the like) are calculated.

This device has a displacement controller (the same as the above-mentioned second arithmetic unit 82), and the displacement controller is a robot geometric model (inverse kinematics arithmetic unit).
The displacement control of the twelve joints of the robot 1 is controlled to follow the joint displacement commands (values) calculated in (1) as target values.

This apparatus comprises the above-mentioned composite compliance operation determining section, and the composite compliance operation determining section corrects the desired foot position / posture trajectory so as to satisfy the following two requirements.

Requirement 1) For controlling the position and orientation of the robot, the actual total floor reaction force is made to follow the resultant force of the compensating total floor reaction force (moment Mdmd) output by the posture stabilization control section and the desired total floor reaction force. . When only the posture inclination of the robot is to be controlled, only the actual total floor reaction force horizontal moment component around the target total floor reaction force center point is made to follow the compensated total floor reaction force moment Mdmd.

Requirement 2) In order to secure the contact property of each foot, the absolute value of the actual foot floor reaction force moment around the target foot floor reaction force center point is reduced as much as possible.

It should be noted that normally, the actual total floor reaction force moment around the desired foot floor reaction force center point is made while making the actual total floor reaction force coincide with the resultant force of the compensation total floor reaction force and the target total floor reaction force. It is often physically impossible to make 0 Therefore, requirements 1) and 2) cannot be completely compatible and must be compromised in some respects.

The operation of this apparatus will be described with reference to the flow chart (structured flow chart) of FIG. 10 on the premise of the above. 4 shows the components of the apparatus shown in FIG. 4 that perform the processing corresponding to the left end of the figure.

First, in S10, the apparatus is initialized, and in S1
The process proceeds to S14 via 2 and waits for a timer interrupt. The timer interrupt is made every 50 ms, that is, the control cycle is 50 ms.

Subsequently, the process proceeds to S16, where it is determined whether or not the gait is switched, that is, the support leg is switched. When the result is negative, the process proceeds to S22. When the result is affirmative, the process proceeds to S1.
The program proceeds to S8, where the timer t is initialized, and proceeds to S20 to set a desired gait parameter. As described above, the gait parameters are the motion parameters and the floor reaction force parameters (ZM
P trajectory parameters).

Then, the program proceeds to S22, in which an instantaneous value of the desired gait is determined. Here, the “instantaneous value” means a value for each control cycle, and the desired gait instantaneous value includes a desired body position / posture, a desired foot position / posture, and a desired ZMP position.
Here, the “posture” is the “direction” in the X, Y, Z space.
Means

Then, the program proceeds to S24, in which a desired foot floor reaction force center point is determined. This is performed as described in the description of the desired floor reaction force distributor. Specifically, as shown in FIGS. 8 and 9, the current time t of the set desired foot floor reaction force center point locus is set.
By determining the value at.

Then, the program proceeds to S26, in which the desired foot floor reaction force is determined. This is performed by calculating each desired foot floor reaction force using Expression 1 described in the description of the desired floor reaction force distributor.

Subsequently, the flow proceeds to S28, where the state of the robot 1 such as the inclination of the body 24 is detected from the output of the inclination sensor 60 and the like.

Subsequently, the flow advances to S30, where a compensated total floor reaction force moment Md (around the desired total floor reaction force center point (target ZMP)) for stabilizing the posture from the state of the robot 1 or the like.
mdx and Mdmdy are obtained. More specifically, the compensation total floor reaction force moments Mdmdx and Mdmdy are calculated according to the above-described equation 2 in order to stabilize the posture when the body inclination is detected.
Is calculated.

Then, the program proceeds to S32, in which actual foot floor reaction forces are detected. This is detected from the output of the six-axis force sensor 44 as described above.

Subsequently, the flow advances to S34, where the leg compensation angle θdbv is set.
And each foot compensation angle θnx (y) is determined. this is,
This is an operation performed by the composite compliance operation determination unit described above.

The operation of the composite compliance operation determining section will be described. For convenience of explanation, the first foot 22R (L) and the second foot 22R (L) are shown in FIG.
It is assumed that actual foot floor reaction force is acting on the foot 22L (R).

Here, the vector Fnact represents the force component of the n-th foot floor reaction force. The vector Mnact represents the moment component of the n-th foot floor reaction force. The direction of the vector Mact indicates that a clockwise moment acts on the foot from the floor with respect to the direction.

It is assumed that the desired total floor reaction force at this moment is as shown in FIG. Incidentally, the desired total floor reaction force moment vector Msumref at the desired total floor reaction force center point (target ZMP) is vertical (by definition, the target ZMP has a horizontal component of the desired total floor reaction force moment of 0).
Is the point).

When this is distributed to the desired foot floor reaction forces in accordance with Equation 1, the result is as shown in FIG. In the figure, a vector Fnref represents a force component of a desired n-th foot floor reaction force. The vector Mnref represents the moment component of the desired n-th foot floor reaction force. The expression of the direction of the vector Mnref is
Same as Mnact.

For the sake of explanation, it is assumed that the body posture is likely to fall to the rear left.

The above-mentioned posture stabilization control calculation unit calculates a compensating total floor reaction force moment Mdmd based on the detected body inclination deviation values θerrx and θerry of the robot 1. In this embodiment, since the spin about the vertical axis (Z axis) is not controlled, the vertical axis component of the compensation total floor reaction force moment Mdmd is zero. Since the swing of the body position is not controlled, the force component of the compensation total floor reaction force moment is also zero. FIG. 14 shows the compensation total floor reaction force moment Mdmd corresponding to this state.

In order to restore the posture, the horizontal component of the actual total floor reaction force moment around the target total floor reaction force center point (target ZMP) is calculated by calculating the desired total floor reaction force moment Msumref and the compensation total floor reaction force moment Mdmd. May be made to follow the horizontal component of the sum of.

On the other hand, the desired total floor reaction force center point (the desired ZMP)
Then, the horizontal component of the desired total floor reaction force moment Msumref is zero. Therefore, in order to restore the posture inclination in the front, rear, left, and right directions, the horizontal component of the actual total floor reaction force moment around the target ZMP should follow the horizontal component of Mdmd.

In this embodiment, the composite compliance operation determining unit corrects the position and posture of the foot so as to satisfy the following requirements as much as possible. Requirement 1) In order to stabilize and control the posture inclination of the robot,
The horizontal (X, Y-axis) components of the actual total floor reaction force moment around the desired total floor reaction force central point (target ZMP) are made to follow the horizontal component of the compensated total floor reaction force moment Mdmd. Requirement 2) In order to secure the contact of each foot, the absolute value of the actual moment of each foot floor reaction force around the target center point of each foot floor reaction force is reduced as much as possible.

However, as described above, the request 1) and the request 2)
Cannot be completely compatible, and must compromise in some respects.

The position / posture of the foot is corrected in this embodiment as follows. 1) A normal vector V including a desired first foot floor reaction force central point Q1 and a desired second foot floor reaction force central point Q2 and perpendicular to the horizontal plane is obtained. The magnitude of V is 1. V to FIG.
Shown in

2) The coordinates of the desired first foot floor reaction force central point Q1 are rotated around the normal vector V about the target total floor reaction force central point (target ZMP) by a certain rotation angle θdbv. The point after the movement is defined as Q1 '. Similarly, the coordinates of the desired second floor floor reaction force central point Q2 are rotated around the normal vector V by the rotation angle θdbv around the desired total floor reaction force central point (target ZMP). Q after moving
2 '.

The rotation angle θdbv is referred to as a two-leg compensation angle.
The vector whose start point is Q1 and whose end point is Q1 'is a vector Q1Q
1 '. Similarly, a vector whose start point is Q2 and whose end point is Q2 'is referred to as a vector Q2Q2'. FIG. 16 shows Q1 ′ and Q
Indicates 2 '.

3) The target first foot is translated (substantially up and down) by the vector Q1Q1 'without changing the posture.
Similarly, the target second foot is moved to the vector Q2 without changing the posture.
Translate by Q2 '. Figure 1 shows the target footprints after moving
6 is indicated by a thick line.

4) Next, the target first foot is rotated by a rotation angle θ1x about the longitudinal axis (X axis) and a rotation angle θ1y about the horizontal axis (Y axis) about Q1 ′. Similarly, the target second foot is rotated by a rotation angle θ2x about the longitudinal axis (X-axis) and a rotation angle θ2y about the horizontal axis (Y-axis) about Q2 ′. The rotation angles θnx and θny are referred to as an nth foot X compensation angle and an nth foot Y compensation angle, respectively. Each target foot after rotation is indicated by a thick line in FIG.

If the amount of compensation operation is not excessive, even if the contact pressure distribution changes, the contact area (the area where the pressure on the sole is positive) does not change. In such a case, the spring mechanism 32 and the sole elastic body 34 attached to each foot are deformed in proportion to the amount of compensation movement, and actual foot floor reaction forces corresponding to the amount of deformation are generated. As a result, the relationship between the amount of compensation operation and the amount of change in the actual floor reaction force generated by the compensation operation has the following favorable characteristics.

Characteristic 1) When the target foot position is moved by operating only the two leg compensation angle θdbv, the force component of the actual foot floor reaction force of the lowered foot increases, and the actual foot floor of the raised foot is increased. The force component of the reaction force decreases. At this time, the actual foot floor reaction force moment around the corrected target foot floor reaction force center point hardly changes.

Characteristic 2) When the desired nth foot posture is rotated by operating only the nth foot X compensation angle, the moment of the actual nth foot floor reaction force acting on the desired nth foot floor reaction force center point Only the X component changes, and the other floor reaction force components change only slightly. Similarly, when the target n-th foot posture is rotated by operating only the n-th foot Y compensation angle, only the Y component of the moment of the actual n-th foot floor reaction force changes, and the other floor reaction force components are Change only slightly.

Characteristic 3) If both feet compensation angle θdbv, each foot X compensation angle and each foot Y compensation angle are simultaneously operated, the change amount of each actual foot floor reaction force is the change amount when each is operated independently. The sum of

The characteristics 1 and 2 indicate that these operations are independent, and the characteristics 3 indicate that these operations have linearity.

FIG. 18 is a block diagram showing the arithmetic processing of the composite compliance operation determining unit. This operation will be described with reference to FIG.

In general terms, the compensating total floor reaction force moment distributor distributes the compensating total floor reaction force moment Mdmd. Next, the two-leg compensation angle determination unit and the n-th foot X
(Y) The compensation angle determination unit determines the compensation angles θdbv and θnx (y).

Next, based on the determined various compensation angles, the corrected target foot position calculating section obtains the compensated foot position / posture (this is referred to as a corrected target foot position / posture) by a geometric calculation. . Lastly, the corrected target foot position / posture calculation unit including the mechanism deformation compensation calculates the deformation amounts of the spring mechanism 32 and the sole elastic body 34 expected to be generated by the desired foot floor reaction forces, and cancels them. Further correct the corrected target foot position / posture.

More specifically, the compensating total floor reaction force moment distributor converts the compensating total floor reaction force moment Mdmd into the two-leg compensation moment Mdmdb and the foot compensation moment Md.
md1x, y, Mdmd2x, y. The two-leg compensation moment Mdmddb is the two-leg compensation angle (foot vertical amount).
By operating θdbv, it is a target value of the moment generated by the force component of each foot floor reaction force around the target total floor reaction force center point (target ZMP).

A component around the V direction of the both leg compensation moment Mdmdb is described as Mdmdbdbv. Note that the vector V is a vector defined in the description of the composite compliance operation determination unit. Assuming that a vector perpendicular to V and also perpendicular to the vertical direction is U, the two-leg compensation moment Mdmdd
The U-direction component Mdmddbu of b is set to 0. This is because the U-direction moment component of the floor reaction force cannot be generated even if the two-leg compensation angle θdbv is operated.

In this embodiment, since the vertical component of the compensated total floor reaction force moment Mdmd is zero, the vertical component Mdmddbz of Mdmdb is also set to zero.

The first foot compensation moment Mdmd1 is a moment to be generated around the desired first foot floor reaction force central point by manipulating the first foot compensation angles θ1x and θ1y. The X component of the first foot compensation moment Mdmd1 is described as Mdmd1x, and the Y component is described as Mdmdly. The second foot compensation moment Mdmd2 is the second foot compensation angle θ
This is a moment to be generated around the target second foot floor reaction force central point by operating 2x and θ2y. Second
The X component of the foot compensation moment Mdmd2 is represented by Mdmd2
The x and Y components are described as Mdmd2y.

The distribution is performed, for example, as follows. Mdmddbv = Wdbx * Mdmdx + Wdby * Mdmdy ・ ・ ・ Equation 3 Mdmd1x = W1x * (Mdmdx-Wint * Vx * Mdmddbv) Mdmd1y = W1y * (Mdmdy-Wint * Vy * Mdmddbv) Mdmd2x = W2x * * dm * Mdmddbv) Mdmd2y = W2y * (Mdmdy-Wint * Vy * Mdmddbv) ・ ・ ・ Equation 4

Here, Wdbx, Wdby, W1x, W
1y, W2x, W2y and Wint are weighting variables for distribution. Vx is the value of the X component of the vector V, and Vy is the value of the Y component of the vector V. Among them, Wint is for canceling the total floor reaction force moment generated by operating the both leg compensation angle by operating each foot compensation angle.

FIG. 19 is a block diagram of a compensating total floor reaction force moment distributor that performs the arithmetic processing of Equations 3 and 4.

Weighting variables Wdbx, Wdb for distribution during walking
FIG. 20 shows a setting example of y, W1x, W1y, W2x, W2y and Wint. The pattern of FIG. 20 is desirably determined in consideration of the following points.

Attention 1) If the leg compensation angle and each foot compensation angle change discontinuously, an excessive torque is generated at the joint.
Therefore, in order to continuously change both leg compensation angles and each foot compensation angle, the distribution weight variable is continuously changed.

Attention 2) The weighting variable for distribution is set so that the actual floor reaction force moment generated by manipulating the two-leg compensation angle and each foot compensation angle is as close as possible to the compensation total floor reaction force moment Mdmd. To determine.

At this time, it is better to change the setting policy as described below according to the situation such as when standing up or walking. As in the case of standing upright, the V-direction component Mdmd of the two-leg compensation moment
dbv, each foot compensation moment Mdmd1, Mdmd2
Is set as follows in the situation where the actual floor reaction force can be generated faithfully.

In this situation, the desired total floor reaction force center point (the desired Z
MP) in order to make the horizontal component of the actual total floor reaction force moment around the same as the horizontal component of the compensating total floor reaction force moment Mdmd (ie, in order to satisfy the above-described requirement 1 to the composite compliance operation determination unit). Equation 5
And Equation 6 should be set so as to satisfy both as much as possible.

Mdmddbv * Vx + Mdmd1x + Mdmd2x = Mdmdx ・ ・ ・ Equation 5 Mdmddbv * Vy + Mdmd1y + Mdmd2y = Mdmdy ・ ・ ・ Equation 6

By substituting Equations 3 and 4, Equation 5 is converted to Equation 7, and Equation 6 is converted to Equation 8. (Wdbx * Mdmdx + Wdby * Mdmdy) * Vx + W1x * (Mdmdx-Wint * Vx * (Wdbx * Mdmdx + Wdby * Mdmdy)) + W2x * (Mdmdx-Wint * Vx * (Wdbx * Mdmdx + Wdby * Mdmdy) ) = Mdmdx ・ ・ ・ Equation 7 (Wdbx * Mdmdx + Wdby * Mdmdy) * Vy + W1y * (Mdmdy-Wint * Vy * (Wdbx * Mdmdx + Wdby * Mdmdy)) + W2y * (Mdmdy-Wint * Vy * ( Wdbx * Mdmdx + Wdby * Mdmdy)) = Mdmdy ・ ・ ・ Equation 8

Even if Mdmdx and Mdmdy take arbitrary values, in order for Equations 7 and 8 to be established equally, Equation 9
It suffices to satisfy Equations 10 and 11 simultaneously. Wint = 1 ... Equation 9 W1x + W2x = 1 ... Equation 10 W1y + W2y = 1 ... Equation 11 That is, in the above situation, weights are set so as to satisfy Equation 9, Equation 10 and Equation 11 simultaneously. Should be determined.

During walking, even if the foot position is corrected by operating the two-leg compensation angle θdbv with Mdmddbv as the target,
In some cases, the amount of the actual total floor reaction force moment is insufficient compared to Mdmddbv. For example, as shown in FIG. 21, in a situation where the first foot has not yet landed due to the robot tilting back in the early stage of the two-leg support period, the actual floor reaction force changes even if the position of the first foot is lowered by θdbv do not do.

Similarly, when the angle of the second foot is corrected by manipulating the second foot compensation angle θ2 with Mdmd2 as a target, the amount of increase in the actual floor reaction force moment is insufficient as compared with Mdmd2. There is. For example, in the situation where the robot is tilted backward in the latter half of the two-leg supporting period as shown in FIG. 22, the actual floor reaction force does not change even if the heel of the second foot is lowered by θ2.

Therefore, even if each weight is set so as to satisfy Equations 5 and 6, the increase in the actual total floor reaction force generated by the composite compliance control is equal to the compensation total floor reaction force moment M.
may not reach dmd. In a situation where such a possibility is high, the value on the left side of Expressions 5 and 6 should be larger than 1.

FIG. 2 is an example of setting distribution weight variables during walking.
At 0, by setting Wint to 0, FIG.
As in the situation described above, even if the actual total floor reaction force moment cannot be generated even if the two-leg compensation angle θdbv is operated, each foot compensation angle is operated to compensate for the shortage.

Conveniently, when the heel of the second foot is lowered as shown in FIG. 21, the heel of the second foot is eventually lowered and it becomes easy to touch the floor. A reaction force moment can be generated.

When the feet are not tilted backward, the actual total floor reaction force moment is generated by operating the two-leg compensation angle θdbv. However, since the heel of the second foot does not touch the floor,
Even if the second foot compensation angle is operated, no actual total floor reaction force moment is generated.

That is, when both feet compensation angle θdbv works effectively, each foot compensation angle does not work effectively, and when each feet compensation angle works effectively, both feet compensation angle θdbv does not work effectively. The total amount of the actual floor reaction force moment generated by manipulating the compensation angle and each foot compensation angle is substantially equal to the compensation total floor reaction force moment Mdmd.

In some situations, the total amount of the actual floor reaction force moment generated by manipulating the both leg compensation angle and each foot compensation angle may be larger than the compensation total floor reaction force moment Mdmd.

However, even in this case, if Mdmd is a feedback operation amount for stabilizing the posture as in this embodiment, there is not much problem. This is because, even if the magnitude of Mdmd is slightly different, it can generally be said to the control system. However, the closed-loop characteristic hardly changes even if the open-loop gain of the control system slightly changes. .

Note 3) In the one-leg supporting period, the absolute values of the distribution weight variables Wdbx and Wdby for the two-leg compensation angle are reduced. This is because, in the one-leg supporting period, even if the two-leg compensation angle is changed, the foot that is not touching the ground simply goes up and down uselessly, and the actual floor floor reaction force does not change.

Attention 4) In order to secure the foot contact property, when the force component of the desired foot floor reaction force is small, the absolute value of the distribution weighting variable for the foot compensation angle of the foot is reduced. I do. Especially when the foot is far from the floor,
Even if the foot compensation angle of the foot is moved, the actual foot floor reaction force of the foot does not change, and therefore, in order to prevent unnecessary movement, the weight for distribution for the foot compensation angle of the foot is used. The absolute value of the variable should be small.

Note 5) The direction of the actual total floor reaction force moment that can be controlled by operating the two leg compensation angles and the direction of the actual total floor reaction force moment that can be controlled by operating each foot compensation angle are usually different. .

For example, the direction of the actual total floor reaction force moment generated by manipulating the two-leg compensation angle θdbv is always in the V direction, and a component orthogonal to the V direction cannot be generated. On the other hand, the direction of the actual total floor reaction force moment that can be generated by operating each foot compensation angle is restricted by the foot contact state.

For example, when only the toe edge or the heel edge is in contact with the ground, no moment can be generated in the edge line direction. In the two-leg supporting period, the two-leg compensation angle and each foot compensation angle are manipulated as much as possible in consideration of this characteristic.

For example, distribution weights Wdbx and Wdby for operating the two-leg compensation angle are determined as follows.

X component is Wdbx, Y component is Wdby, Z
Assuming that a vector having zero component is Wdb, Equation 3 is an inner product of the vector Wdb and Mdmd. Therefore, Mdm
Decompose d into a vector Wdb direction component and its orthogonal component,
By extracting only the component in the vector Wdb direction, the vector Wd
Multiplied by the magnitude of b is M
dmdbbv.

FIG. 23 shows Mdmddbv in this case. This means that a feedback control system that controls the Wdb direction component of the actual total floor reaction force moment by manipulating the two-leg compensation angle is meant. If the Wdb direction is orthogonal to the vector V, no matter how much the two-leg compensation angle is manipulated, the Wdb-direction component of the actual total floor reaction force moment will not be generated. Just do it.

Therefore, when unnecessary movements are reduced,
The Wdb direction should match or be as close as possible to the vector V direction. Also, if it is desired to generate the Wdb direction component of the compensation total floor reaction force moment Mdmd simply by operating the two-leg compensation angle without depending on each foot compensation angle,
The inner product of Wdb and V is set to 1. If you want a part to depend on each foot compensation angle, the inner product of Wdb and V is 1
Set to be smaller.

When the lateral width of the foot is small, the X component of the actual foot floor reaction force moment that can be generated by operating each foot compensation angle becomes small. In this case, Wdbx is set to be relatively large. The Wdb direction and the vector V direction do not match, and the fluctuation of the leg compensation angle increases, but the stability increases.

The two-leg compensation angle determination unit will be described in further detail. FIG. 24 is a block diagram of the calculation processing of the two-leg compensation angle determination unit, and the two-leg compensation angle θdbv is calculated as shown.

Referring to FIG. 24, F1act acting on desired first foot floor reaction force central point Q1 and F2act acting on desired second foot floor reaction force central point Q2 are determined by the desired total floor reaction force central point. Moment Mf1f generated around P
2act is obtained by the following equation.

Mf1f2act = PQ1 * F1act + PQ2 * F2act (12) where PQ1 is a vector whose start point is P and whose end point is Q1,
Q2 is a vector whose start point is P and whose end point is Q2.

Also, even if the following equation is used instead of equation 12, there is practically no problem. Mf1f2act = PQ1 * F1act + PQ2 * F2act + M1act + M2act Equation 12a Equation 12a is an equation for calculating the actual total floor reaction force moment Mnact acting around the target total floor reaction force center point. Expression 12 is obtained by subtracting the actual foot floor reaction force moment acting around the desired foot floor reaction force central point from the actual total floor reaction force moment acting around the target total floor reaction force center point. ing. The statement in claim 4 is based on this.

Next, a vector V-direction component Mf1f2actv of Mf1f2act is extracted. This is obtained by the following equation using a vector inner product operation. Note that the vector V is V shown in FIG. 15 in the above description of the operation. Mf1f2actv = Mf1f2act · V ・ ・ ・ Equation 13

Next, Mf1f2actvfilt is obtained by passing Mf1f2actv through a low-pass filter.

Next, a two-leg compensation moment V-direction component Md
The mddbv is passed through a compensating filter, and is passed through Mf1f
2actvfilt to obtain a deviation moment V-direction component Mdiffv.

The compensating filter improves the frequency response characteristics of the transfer function from Mdmdbbv to the actual total floor reaction force moment.

Next, a two-leg mechanism deformation compensation angle θffdbv for canceling the effect of the deformation of the foot spring mechanism on the V-direction component of the two-leg compensation moment is obtained. This is so-called feed-forward compensation.

More specifically, a desired first foot floor reaction force center point Q1 is determined using a mechanism compliance model representing the relationship between the two-leg compensation moment V-direction component Mdmdbbv and the amount of deformation.
And the desired second foot floor reaction force center point Q2, the deformation angle of the line segment is obtained, and the inverted polarity of the angle is used as the two-leg mechanism deformation compensation angle θffdbv.

The two-leg mechanism deformation compensation angle θffdbv can be approximately obtained by the following equation. θffdbv = −α * Mdmddbv Expression 14 where α is a predetermined constant.

Finally, a two-leg compensation angle θdbv is obtained by the following equation. Here, Kdb is a control gain, which is usually set to a positive value. θdbv = Kdb * Mdiffv + θffdbv ・ ・ ・ Equation 15

The n-th foot compensation angle determination unit will be described. FIG. 25 is a block diagram showing the calculation processing of the first foot X compensation angle determination unit, in which the first foot X compensation angle θ1x is shown. Is calculated as follows. Although the description is omitted, the first foot Y compensation angle θ1y, the second foot X compensation angle θ2x, and the second foot Y compensation angle θ2y are similarly obtained. Here, the first foot X compensation angle θ
Only the algorithm for obtaining 1x will be described.

First foot floor reaction force moment X component M1ac
tx is passed through a low-pass filter and M1actfiltx
Get. The first foot compensation moment X component Mdmd1x is passed through a compensation filter, and is passed through M1actfiltx.
To obtain the deviation moment Mdiff1x. As with the determination of the two-leg compensation angle, the compensation filter improves the frequency response characteristics of the transfer function from Mdmd1x to the actual total floor reaction force.

Next, similarly to the determination of the two-leg compensation angle, the first foot X mechanism deformation compensation angle θff for canceling the influence on the first foot compensation moment X component due to the deformation of the foot spring mechanism or the like.
Find 1x. This is so-called feed-forward compensation.

Specifically, the deformation angle of the first foot is obtained by using a mechanism compliance model representing the relationship between the first foot compensation moment V-direction component Mdmd1x and the amount of deformation.
What is obtained by reversing the polarity may be set as the first foot X mechanism deformation compensation angle θff1x.

The first foot X mechanism deformation compensation angle θff1x is
Approximately, it can be obtained by the following equation. θff1x = −α1x * Mdmddbv Expression 16 where α1x is a predetermined constant.

Finally, the first foot X compensation angle θ1 is obtained by the following equation.
Get x. Here, K1x is a control gain, which is usually set to a positive value. θ1x = K1x * Mdiff1x + θff1x Expression 17 Note that the block diagram shown in the drawing may be subjected to an equivalent modification such as changing the operation processing order.

Referring back to FIG. 18, the corrected target foot position / posture calculation unit calculates the two-leg compensation angle θdbv, the first foot X compensation angle θ1x, the first foot Y compensation angle θ1y, and the second foot. Based on the flat X compensation angle θ2x and the second foot Y compensation angle θ2y, the target foot position / posture is corrected according to the foot position / posture correction method of the composite compliance operation described above to obtain a corrected target foot position / posture. .

The mechanism deformation calculator calculates the spring mechanism 32 and the sole elastic body 34 which are expected to be generated by the desired foot floor reaction force.
Is obtained.

The corrected target foot position / posture with mechanism deformation compensation further corrects the corrected target foot position / posture so as to cancel out the calculated amount of mechanism deformation, and the corrected target foot position with mechanism deformation compensation.・ Get the posture.

For example, when the amount of mechanical deformation as shown in FIG. 26 is predicted, the corrected target foot position / posture with mechanical deformation compensation is corrected to the position / posture shown by solid lines in FIG. That is, the position / posture when the foot after the mechanism deformation compensation shown in FIG. 27 is deformed by receiving the desired foot floor reaction force is as shown in FIG.
The corrected target foot position / posture with the mechanism deformation compensation is calculated so as to match the foot position / posture before the mechanism deformation compensation shown in FIG.

The mechanism deformation compensation is a control for canceling the deviation of the actual foot position and posture caused by the deformation of the spring mechanism 32 and the sole elastic body 34 in a feed-forward manner. Thus, it is possible to realize a walking close to the desired gait.

Returning to the description of the flow chart of FIG. 10 on the premise of the above, as described above, the above-mentioned compensation angle is determined in S34.

FIG. 28 is a subroutine flowchart showing the operation.

The description will be made with reference to FIG.
, The vector V described above is obtained, and the process proceeds to S102, where the distribution weight variables are set as shown in FIG. 20, and these values at the current time t are obtained. Then, the process proceeds to S104, and the total floor reaction force moment Mdmd is compensated by Expressions 3 and 4.
Is distributed to both feet compensation moment Mdmddbv and each foot compensation moment Mdmdnx (y), the flow proceeds to S106 to obtain the two-leg compensation angle θdbv as described above, and proceeds to S108 to obtain each foot compensation angle θnx (y).

Then, the flow advances to S36 in the flow chart of FIG. 10 to calculate a mechanism deformation compensation amount based on the desired foot floor reaction force, and advances to S38 to set the target foot position / posture to the compensation angle θd.
bv, θnx (y), and further corrects it according to the mechanism deformation compensation amount to obtain a corrected target foot position / posture with mechanism deformation compensation.

Then, the process proceeds to S40, in which a joint displacement command (value) is calculated from the body position / posture and the corrected foot position / posture including the mechanism deformation compensation, and the process proceeds to S42, where the actual joint displacement is calculated. Value), the process proceeds to S44 to update the time by Δt, and returns to S14 to repeat the above processing.

Since this embodiment is configured as described above, the control of the actual total floor reaction force and the control of the actual foot floor reaction force hardly interfere with each other. Can be controlled.

That is, the device according to this embodiment has the following improvements over the previously proposed technology. That is, in the ankle compliance control proposed in Japanese Patent Application Laid-Open No. 5-305584, an actual floor reaction force moment at a point fixed to the foot such as a reference point of an ankle or a sole is detected, and the fixed moment is detected based on the detected moment. The apparatus according to this embodiment calculates actual foot floor reaction force moments at the moving target foot floor reaction force center point, and calculates the desired foot floor reaction force based on the moment. The foot was changed to rotate around the center point, and the moment around that point was controlled to a desired value.

As a result, it was possible to easily control the actual total floor reaction force and the actual foot floor reaction force with little interference. To reduce the interference, a more appropriate point may be selected in the sole contact area assumed at each moment.

Further, the floor reaction force acting on the robot, more specifically, the actual total floor reaction force moment around the desired total floor reaction force center point (desired ZMP) and the actual each foot around the desired foot flat center point. The flat floor reaction force moment can be easily and appropriately controlled. In other words, compared to the previously proposed combined use of the two-leg compliance control and the ankle compliance control, there is no control interference, and the actual total floor reaction force and the actual floor floor reaction force can deviate or oscillate from desired values. Absent.

Therefore, even if there is an unexpected floor shape change including not only global undulations and slopes but also local irregularities and slopes, the floor counteracting on the legged mobile robot is not affected so much. The force can be controlled appropriately.

In addition, the posture stabilization control of the legged mobile robot can be easily realized, the landing impact received by the legged mobile robot can be reduced, the grounding property of the legged mobile robot can be increased, and slip during walking can be improved. And spin can be prevented. Further, the load on the actuator of the legged mobile robot can be reduced.

In the two-leg compliance control proposed in Japanese Patent Application Laid-Open No. Hei 5-305586, the desired total floor reaction force center point (target ZMP) of the actual total floor reaction force (the resultant force of each foot floor reaction force) is obtained.
Although the surrounding moment component is detected and controlled so that the value becomes a desired value, in the apparatus according to the present embodiment, of the foot floor reaction forces acting on the target foot floor reaction force center points, Is changed so as to detect a moment acting around the target total floor reaction force center point (target ZMP) by synthesizing the translational force component excluding the moment component of (1), and to control the value to a desired value (in addition, This point may be the control method proposed earlier).

FIG. 29 is an explanatory view similar to FIG. 16, but showing a second embodiment of the control device for a legged mobile robot according to the present invention.

The device according to the second embodiment simplifies the compensation operation. In this embodiment, as a method of the foot position correcting operation for operating the force component of the floor reaction force of each foot, instead of the method shown in FIG. 16, as shown in FIG.
Moved only in the vertical direction. At this time, the first
Foot vertical movement amount Z1 and second foot vertical movement amount Z2
Is determined by the following equation. Z1 = -length of line segment PQ1 * θdbv Z2 = length of line segment PQ2 * θdbv Expression 18 Here, the value obtained by Expression 15 is substituted for θdbv.

The other configuration is not different from that of the first embodiment. In the second embodiment, with the above-described configuration, substantially the same operation as in the first embodiment,
The effect can be obtained.

FIG. 30 is an explanatory view similar to FIG. 4, but showing a third embodiment of the control device for a legged mobile robot according to the present invention. FIG. 31 shows the operation.
It is a flow chart similar to.

In the third embodiment, the compliance control for the Z component (the component around the vertical axis) of the actual total floor reaction force moment is added. That is, in the third embodiment, the Z component of the actual foot floor reaction force moment caused by the natural rotational vibration about the Z axis is reduced.

In the third embodiment, new functions are added to the configuration of the device according to the first embodiment, and to the state detector, the attitude stabilization control operation unit, and the composite compliance operation determination unit. Was added.

Referring to FIG. 30, in the apparatus according to the third embodiment, first, the upper
4, a self-position / posture / direction estimator 102 for estimating the current position, posture, and traveling direction while inputting the output and the like of the yaw rate sensor 100 at appropriate positions.
Was prepared. The yaw rate sensor 100 outputs a signal corresponding to the yaw rate (rotational angular velocity) of the robot 1 around the Z axis. Note that the rotational angular velocities around the X and Y axes are calculated based on the output of the tilt sensor 60.

The self-position / posture / direction estimator 102 calculates the relative position and direction of the current landing position with respect to the landing position one step before based on the target foot trajectory or the actual joint angle, and detects the detected value of the yaw rate sensor 100. , The traveling direction of the robot is detected.

Further, based on such information, the position deviation and the direction deviation of the robot 1 with respect to the target path are estimated by dead reckoning. Since the error of the estimated value tends to diverge in dead reckoning, the environment may be recognized and corrected using a camera or the like. Also, upper body 24
Is tilted with respect to the vertical axis, the yaw rate detection value at the time of turning becomes smaller than the actual value. Therefore, it is desirable to correct the yaw rate detection value by the output of the tilt sensor 60.

The device according to the third embodiment will be described with reference to the flowchart of FIG. 31.
Then, in S30a, based on the estimated position and / or direction deviation of the robot 1, the Z component M of the compensating total floor reaction force moment is reduced so as to reduce the deviation.
Find dmdz.

In the following, a case where the user walks along the route shown in FIG. 32 will be described as an example. The following equation is used as a control rule for obtaining the Z component Mdmdz of the above-described total floor reaction force moment. Mdmdz = −Kthzθerrz−Kwz (dθerrz / dt) −Khzh (19) where θerrz is the direction shift, dθerrz / dt
Is the time differential value, and h is the lateral deviation from the path. The figure shows θerrz, h. In the state of this figure, θerrz,
h is positive. Kthz, Kwz and Khz are route guidance control gains (constants).

As described above, when the robot 1 is walking, the torso elasticity of the foot spring mechanism 32 and the torsion elasticity of the sole elastic body 34 and the moment of inertia around the vertical axis of the robot 1 cause the upper body 24 to move in the vertical axis. Vibrates around. This is called natural rotation vibration about the Z axis. With this vibration, the Z component of the actual foot floor reaction force moment vibrates. When the robot 1 is walking, the actual foot floor reaction force is substantially the sum of the desired foot floor reaction force moment and the above vibration.

When the amplitude of the vibration becomes excessive, the peak value of the actual foot floor reaction force moment exceeds the limit of friction, and at that moment, the sole slides, and the robot 1 spins. If the spin is large, the person may lose posture stability and fall. In other words, it can be understood that the effect of improving the posture stability can be obtained simply by suppressing the natural rotational vibration about the Z axis.

If the natural rotational vibration around the Z axis is simply suppressed, the Z component Mdmd of the total floor reaction force moment is calculated from only the deviation of the yaw rate (the time differential value of the direction deviation).
z may be determined. That is, in Equation 19, the route guidance control gain other than Kwz may be set to zero.

Further, in the third embodiment, a new function is added to the composite compliance operation determining section.
Specifically, in order to manipulate the moment components around the Z axis of the actual total floor reaction force and the actual foot floor reaction force, the operation of correcting the position and orientation of the foot 22R (L) in the first embodiment is performed. In addition to behavior. The composite compliance operation determination unit determines this correction amount.

Before describing the determination method, the added operation will be specifically described below.

The correction of the position and orientation of the foot for manipulating the Z-axis moment component of the total floor reaction force and each foot floor reaction force is as follows.
The corrected target foot position / posture (the thick line foot in FIG. 16) and the corrected target foot floor reaction force center point (Q in FIG. 16) obtained by the composite compliance operation described in the first embodiment.
1 ', Q2') by making the following modifications.

1) Corrected target first foot floor reaction force center point (FIG. 1)
6, the coordinate of Q1 ′) is set to the desired total floor reaction force action point (target ZM
A certain rotation angle θdbz around the Z axis around the rotation center P)
Rotate only. The point after moving is Q1 "
And

Similarly, the desired second foot floor reaction force center point (FIG. 1)
6, the coordinate of Q2 ′) is set to the desired total floor reaction force action point (the desired ZM
A certain rotation angle θdbz around the Z axis around the rotation center P)
Rotate only. The point after moving is Q2 "
And This rotation angle θdbz is referred to as a two-leg compensation angle around the Z axis.

A vector whose start point is Q1 'and whose end point is Q1 "is defined as a vector Q1'Q1". Similarly, a vector whose start point is Q2 'and whose end point is Q2 "is referred to as a vector Q2'Q2". FIG. 33 shows Q1 "and Q2" viewed from above.

3) The corrected target first foot is translated by the vector Q1′Q1 ″ without changing the posture. Similarly, the corrected target second foot is moved in the vector Q1 without changing the posture.
The translational movement is performed by 2'Q2 ". Each corrected target foot after the movement is indicated by a thick line in FIG.

4) Next, the corrected target first foot obtained in 3) is rotated about the vertical axis (Z-axis) by a rotation angle θ1z around Q1 ″. Similarly, obtained in 3). The corrected correction target second foot is rotated about the vertical axis (Z axis) by the rotation angle θ2z around Q2 ″. The rotation angle θnz is referred to as an n-th foot Z compensation angle. Figure 3 shows the corrected target foot after rotation.
4 is shown by a thick line.

If the amount of compensation operation is not excessive, the relationship between the amount of compensation operation and the amount of change in the actual floor reaction force generated by the compensation operation has the following good characteristics.

Characteristic 1) When each of the corrected target foot positions is moved by operating only the both leg compensation angle θdbz around the Z axis, a force component of the actual foot floor reaction force is generated in a direction opposite to the moving direction. At this time, the actual foot floor reaction force moment around the corrected target actual foot floor reaction force center point hardly changes.

Characteristic 2) When the desired foot posture is rotated by operating only the n-th foot Z compensation angle, the moment of the actual n-th foot floor reaction force acting on the desired n-th foot floor reaction force center point is calculated. Only the Z-axis component changes, and the other floor reaction force components change only slightly.

Characteristic 3) Both leg compensation angle θdbz, each foot X compensation angle, each foot Y compensation angle, both leg compensation angle θdbz around Z axis
When the foot Z compensation angles are simultaneously operated, the change amount of each actual foot floor reaction force is the sum of the change amounts when each is operated independently (in other words, linear combination is enabled).

The characteristics 1 and 2 indicate that these operations are independent, and the characteristic 3 indicates that all operations have linearity.

In the above operation, the two-leg compensation angle θdbz around the Z axis and each foot Z compensation angle are determined by the composite compliance operation determining unit as follows.

FIG. 35 is a schematic block diagram of a composite compliance section according to the third embodiment. As shown, a moment Z-component compensation operation determining unit 104 is added. FIG.
The details of the moment Z-component compensation operation determining unit 104 are shown in FIG. Hereinafter, description will be made focusing on this additional portion.

As shown in FIG. 36, in the Z-component compensation moment determining unit 104, the Z-component Mdmdbz of the two-leg compensation moment Mdmdb and the foot compensation moment Mdmd1 are obtained from the output of the compensating total floor reaction force moment distributor.
z, Mdmd2z, and the compensation moment Z component (Mdmddbz, M
dmnz), etc., the two-leg compensation angle θdb around the Z axis.
z, the first foot Z compensation angle θ1z and the second foot Z compensation angle θ
Determine 2z. (This is S in the flow chart of FIG. 38)
34a).

The corrected target foot position / posture calculation unit obtains the corrected foot position / posture including the both-legs compensation angle around the Z-axis and each foot Z-compensation angle by geometric calculation.

The details of the additional processing will be described below.

The distribution of the compensating total floor reaction force moment will be described with reference to FIG. 37. In the compensating total floor reaction force moment distributor, the Z component M of the compensating total floor reaction force moment Mdmd
dmdz is a Z component Mdmddbz of the both leg compensation moment Mdmdb, a Z component Mdmd1z of the first foot compensation moment Mdmd1, and a second foot compensation moment Mdmd.
A process of distributing the Z component Mdmd2z is added.

The Z component of the two-leg compensation moment Mdmd
dbz is a target value of the Z component of the moment generated by the force component Fnact of each foot floor reaction force around the target total floor reaction force center point (target ZMP) by operating the two-leg compensation angle θdbz.

Further, the Z component M of the first foot compensation moment
dmd1z is a moment Z component (indicated by M1 in FIG. 34) to be generated around the desired first foot floor reaction force center point by manipulating the first foot compensation angle θ1z. Similarly, the Z component Mdmd2 of the second foot compensation moment is the moment Z component to be generated around the desired second foot floor reaction force center point by operating the second foot compensation angle θ2z (M2 in FIG. 34). Shown).

The distribution is performed using, for example, the following equation. Mdmddbz = Wdbz × Mdmdz Mdmd1z = W1z × Mdmdz Mdmd2z = W2z × Mdmdz Expression 20 Here, Wdbz, W1z, and W2z are weighting variables for distribution during walking. The distribution weight variables Wdbz, W1z,
FIG. 38 shows an example of setting W2z. The setting pattern shown in the figure is determined in consideration of the following points.

Attention 1) If the both leg compensation angle and each foot compensation angle change discontinuously, an excessive torque is generated at the joint.
Therefore, in order to continuously change both leg compensation angles and each foot compensation angle, the distribution weight variable is continuously changed.

Note 2) The Z component of the actual floor reaction force moment generated by manipulating the both leg compensation angle around the Z axis and each foot Z compensation angle is as close as possible to the Z component Mdmdz of the compensated total floor reaction force moment. The distribution weight variables Wdbz, W1z, and W2z are determined so as to have the values.

In a situation where the Z component Mdmddbz of the leg compensation moment and the foot compensation moment Z components Mdmd1z and Mdmd2z can be faithfully generated in the actual foot floor reaction force as in the case of standing upright as follows, Set. That is, the Z component of the actual floor reaction force moment Mact around the desired total floor reaction force center point (target ZMP) is made to match the Z component of the compensated total floor reaction force moment Mdmd (in other words, the first embodiment). In order to satisfy the requirement 1 for the composite compliance operation unit described in
Is set to satisfy as much as possible.

Wdbz + W1z + W2z = 1 Equation 21 Note that when walking, it is sufficient if the left side of Equation 21 is close to 1. In other words, it does not necessarily have to be one.

Attention 3) If both legs compensating angle θdbz around the Z axis is not 0 at the time when the free leg foot lands, the foot landing position may deviate from the target position, which may adversely affect the trajectory guidance control. Therefore, it is desirable to set the distribution weight variable Wbz for the double leg compensation angle around the Z axis to 0 near the time when the foot lands.

Attention 4) If the Z-compensation angle of the free leg foot is not zero when the foot lands, the foot landing direction deviates from the target direction, which may adversely affect the trajectory guidance control.
Therefore, near the time when the first foot lands, the distribution weight variable W1z for the first foot Z compensation angle is set to 0, and by the time the second foot lands, the distribution weight variable W1z for the second foot Z compensation angle is set. Weight variable W for distribution
It is desirable to set 2z to 0.

Further, a process of determining the two-leg compensation angle θdbz around the Z axis is added. Compensation angle θdbz around the Z axis
Is obtained by the same algorithm as the two-leg compensation angle θdbv. The only difference is that the directions of the moment and the angle have changed from the V direction to the Z direction. Therefore, a block diagram of the processing for determining the two-leg compensation angle θdbz around the Z axis can be obtained by replacing V in FIG.

Further, a process for determining the first foot compensation angle θ1z and the second foot compensation angle θ2z is added. The nth foot Z compensation angle θnz is obtained by the same algorithm as that for obtaining the first foot X compensation angle θ1x. The only difference is that X has changed to Z and 1 has changed to n. Therefore,
A block diagram of the processing for determining the n-th foot Z compensation angle θnz can be obtained by replacing X in FIG. 25 with Z and 1 with n.

The above-described subroutine of the processing performed in S34a of FIG. 31 is performed in steps S200 to S206 of FIG.
Shown in

Based on the above, in calculating the corrected target foot position / posture (corresponding to S38 in the flow chart of FIG. 31), the two-leg compensation angle θdbv and the two-leg compensation angle θdb around the Z-axis.
z, first foot X compensation angle θ1x, first foot Y compensation angle θ1
y, first foot Z compensation angle θ1z, second foot X compensation angle θ2
x, second foot Y compensation angle θ2y, second foot Z compensation angle θ2z
Based on the above, the target foot position / posture is corrected in accordance with the foot position / posture correction method of the composite compliance operation to which the above-described Z-axis compensation operation is added, to obtain a corrected target foot position / posture.

In the third embodiment, as described above, the compliance control for the Z component (the component about the vertical axis) of the actual total floor reaction force moment is added, so that the operation and effects described in the previous embodiment are added. In addition, it is possible to suppress the vibration of the Z component of the actual floor floor reaction force moment due to the natural rotational vibration about the Z axis, and thus to more effectively realize the posture stabilization control of the legged mobile robot. it can.

Further, also when performing the route guidance control shown in FIG. 32, the vehicle can be guided with high accuracy along the intended route.

In the third embodiment, the yaw rate sensor 100, the self-position / posture / direction estimator 102, the route guidance control operation unit, and the like are not provided, and the Z component Mdmdz of the compensation total floor reaction force moment is simply set to zero. Or, just fixing it in the vicinity thereof is quite effective as compliance control for the Z component of the actual total floor reaction force moment. Claim 9 is based on this description.

In the first to third embodiments, as described above, at least the base (upper body 24) is connected to the base via the first joint (10, 12, 14R (L)). , A second joint (18, 20R (L)) at the tip
In the control device for a legged mobile robot comprising a plurality of (two) legs (leg links 2) having feet (foot 22R (L)) connected via Movement patterns (target body position / posture, target foot position / posture) including the target position and posture of the foot, and target patterns of total floor reaction force acting on the robot (target total floor reaction force, target total floor) Gait generating means (gait generator, S10 to S22) for generating a gait of the robot including at least a reaction force center point (= target ZMP), and calculating the total floor reaction force of the generated gait to the foot Means for determining a desired foot floor reaction force center point (a desired foot floor reaction force center point) as an action center point on the foot when distributed to each of the feet. Floor reaction force distributor, S24, S26), actual floor acting on the foot Actual floor reaction force detecting means (6-axis force sensor 44, actual foot floor reaction force detector, S32) for detecting the force (actual foot floor reaction force), and the detected actual floor reaction force is calculated. Moment acting around the desired foot floor reaction force center point (actual nth foot floor reaction force moment Maxx, y, z)
And the amount of rotation for rotating the foot based on at least the calculated moment (both legs compensation angle θdb)
v, z, n-th foot compensation angle θnx, y, z) foot rotation amount determining means (composite compliance operation determining unit,
S32 to S34, S34a, both legs compensation angle determination unit, n-th
Foot compensation angle determination unit, S100 to S108 and S20
0 to S206), the foot position for correcting the target position and / or posture such that the position and / or posture of the foot is rotated based on the determined foot rotation amount.
Posture correction means (Composite compliance operation determination unit, S3
8, S40, a corrected target foot position / posture calculation unit), and first and second joints (10, 12, 14, 1) of the robot based on the corrected position / posture of the foot.
8, 20R (L)) is configured to include a joint displacement means (robot geometric model (kinematics calculation unit), displacement controller, S40, S42).

Further, at least the base (upper body 24) is connected to the base via the first joint (10, 12, 14R (L)), and the second joint (18, 18
20R (L)) (foot 22R)
(L)), the control device of the legged mobile robot 1 including a plurality of (two) legs (leg links 2);
A movement pattern (target body position / posture, target foot position / posture) including at least the target position and posture of the foot of the robot, and a target pattern of total floor reaction force acting on the robot (target total floor reaction) Gait generating means (gait generator, S10 to S2) for generating a gait of the robot including at least a force and a desired total floor reaction force central point (= target ZMP)
2) a desired foot floor reaction force center point (a desired foot floor floor reaction force center) which is an action center point on the foot when the generated total floor reaction force of the gait is distributed to each of the feet; Means for determining the desired foot floor reaction force center point (target floor reaction force distributor,
S24), actual floor reaction force detecting means (6-axis force sensor 44, which detects actual floor reaction force (actual foot floor reaction force) acting on the foot portion;
Actual foot floor reaction force detector, S32), the amount of rotation for rotating the foot based on at least the detected actual floor reaction force (both leg compensation angles θdbv, z, n-th foot compensation angle θnx,
y, z) foot rotation amount determining means (composite compliance operation determining unit, S32, S34, S34a, both leg compensation angle determining unit, nth foot compensation angle determining unit, S100 to S
108 and S200 to S206) such that the position and / or posture of the foot is rotated around the determined target foot floor reaction force center point or its vicinity based on the determined foot rotation amount. , The target position and / or
Or, the foot position / posture correction means (combined compliance operation determination unit, S38, S40, correction target foot position / posture calculation unit) for correcting the posture, and the robot based on the corrected foot position / posture The first and second joints (10, 12, 14, 18, 20R (L)) are displaced by a joint displacing means (robot geometric model (kinematics calculation unit), displacement controller, S42) did.

The foot position / posture correcting means may determine whether the position and / or posture of the foot is based on the determined foot foot reaction force center point or the determined foot foot reaction force center point based on the determined foot rotation amount. The target position and / or posture is modified so as to rotate around the vicinity thereof.

Further, the total floor reaction force moment actually acting on the robot (more precisely, the moment component PQ1 *
F1act + PQ2 * F2act + M1act + M2act) or the total floor reaction force actually acting on the robot (PQ1 *
Moment (Mf1f2act = PQ1 * F1act +) obtained by subtracting the floor reaction force moment (M1act + M2act) acting on the foot from F1act + PQ2 * F2act + M1act + M2act
PQ2 * F2act) and a foot movement determining means (combined compliance operation determining unit, S34) for determining a moving amount (θdbv, z) for moving the foot at least according to the calculated moment. , S34a, a two-leg compensation angle determination unit, S100 to S108, and S200 to S206), wherein the foot position / posture correction means performs the foot rotation based on the determined foot rotation amount and the determined movement amount. The position and / or posture of the part is configured to be corrected.

The posture stabilizing compensation total floor reaction force moment (compensation total floor reaction force Mdmd) to be added to the total floor reaction force target pattern is obtained, and the foot rotation amount determining means and / or the foot movement is calculated. The amount determining means determines a rotation amount and / or a movement amount of the foot based on at least the detected actual floor reaction force (actual foot floor reaction force) and the determined posture stabilization compensation total floor reaction force moment. Is determined (S34, S34a,
(S100 to S108, S200 to S206).

Further, the posture stabilization compensation total floor reaction force moment is calculated by using at least the inclination deviation (θerr
x, y) (S28, S30a).

The posture stabilization compensation total floor reaction force moment is calculated at least by the yaw rate (θer
rz, dθerrz / dt) (S2
8, S30a).

The posture stabilization compensation total floor reaction force moment is obtained based on at least a deviation from the target path of the robot, that is, a lateral deviation or a direction deviation h from the target trajectory (S28, S30a). .

A predetermined component (Md) in the posture stabilization compensation total floor reaction force moment (compensation total floor reaction force Mdmd)
mdz) is set to zero or its vicinity.

In addition, the foot position / posture correcting means is configured to determine the target position and / or posture based on the posture deviation of the robot.
Or, the posture was further modified.

The foot rotation amount determination means and / or the foot movement amount determination means may be arranged such that the posture stabilization compensation total floor reaction force moment is distributed to each of the plurality of legs. The amount of rotation and / or the amount of movement of the foot is determined (S34, S34a, S100 to S10).
8, S200 to S206).

Further, at least the base (upper body 24) and the base are connected to the base via first joints (10, 12, 14R (L)), and the second joints (18,
20R (L)) (foot 22R)
(L)), the control device of the legged mobile robot 1 including a plurality of (two) legs (leg links 2);
A movement pattern (target body position / posture, target foot position / posture) including at least a target position and posture of the foot of the robot, and a target trajectory pattern of a total floor reaction force acting on the robot (target total floor) Gait generating means (gait generator, S10 to S22, S) for generating a gait of the robot comprising a reaction force and a desired total floor reaction force center point (= target ZMP)
24) posture stabilization compensation total floor reaction force calculating means (posture stabilization control calculation unit, S30, S) for calculating a compensation total floor reaction force (compensation total floor reaction force Mdmd) for stabilizing the posture of the robot;
30a) a foot floor reaction force detecting means (6-axis force sensor 4) for detecting an actual floor reaction force (actual foot floor reaction force) acting on the foot;
4, actual foot floor reaction force detectors (S32), floor reaction force distribution means (target floor reaction force distributors, S34, S34a, and S34) for distributing the total floor reaction force of the target gait and the compensation total floor reaction force. S100 to S104, S200 to S202), based on the distributed desired gait floor reaction force, the compensated floor reaction force, and the detected actual foot reaction force, the position and / or position of the foot of the desired gait. Or correction means for correcting the posture (composite compliance operation determination unit, S36 to S38, compensation angle determination unit, mechanism deformation amount calculation unit, correction target foot position / posture calculation unit, correction target foot position / posture calculation with mechanism deformation compensation) And first and second joints (10, 12, 14, 18, 20, 20) of the robot based on the corrected target foot position and posture.
R (L)) is configured to include a joint displacement control means (robot geometric model (kinematics calculation unit), displacement controller, S40, S42).

Further, the correction means is configured to further correct the position and / or posture of the foot of the desired gait based on the posture deviation of the robot.

In the first to third embodiments, the method of obtaining the center of rotation of the foot in the compensating operation is further expanded.
Instead of the desired center point of the foot floor reaction force as shown in FIG. 17, another point in the sole contact area assumed at that moment may be set as the rotation center point.

[0279] Examples of the setting method are listed below. Although the calculation process becomes complicated, in some cases, even when the foot is rotated, only the foot actual floor reaction force moment changes, and the force component of the foot actual floor reaction force does not further interfere. You can do so. However, in any case, care should be taken so that the movement locus of the foot rotation center point does not become discontinuous.
This is because, if discontinuous, the compensating operation changes rapidly and the foot flaps.

Method 1) From the compensating moments and the force components of the desired foot desired floor reaction force, the position where the actual foot floor reaction force center point should be when the respective compensating moments are generated is determined. It is called each foot floor reaction force center point. However, the corrected target floor floor reaction force central point is set so as not to exceed the sole contact area assumed at that moment. Correction target Each foot floor reaction force center point or the vicinity thereof is set as a rotation center point.

Method 2) The area center point of the assumed sole contact area is determined, and the point or the vicinity thereof is set as the rotation center point.

Method 3) The actual foot floor reaction force center point is determined from the actual foot floor reaction force, and the point or the vicinity thereof is set as the rotation center point.

Method 4) A plurality of candidates are selected from among various rotation center point candidates and target foot floor reaction force center points listed in Methods 1 to 3, and the point of the weighted average is set as the rotation center point.

In the above description, unless a negative pressure is generated in a part of the pressure distribution in the sole contact area, that is, as long as no adhesive force is generated, the actual foot floor reaction force center point must be within the sole contact area. Exists.

In the first to third embodiments described above, in FIG. 4, instead of inputting the desired body position / posture trajectory as it is to the robot geometric model,
The applicant first calculates the body height from the horizontal position of the desired body position / posture trajectory and the corrected target foot position / posture trajectory.
The correction may be made by recalculation using the body height determination method proposed in No. 214260, and the corrected value may be input to the robot geometric model.

If the target foot position / posture trajectory is significantly corrected, there is a possibility that the legs may be stretched completely and the posture cannot be taken if the original body height is maintained. In such a case, if the recalculation is performed, there is no possibility that the leg will be extended unless there is a sufficient time.

In the first to third embodiments, when the upper body is tilted, the position of the actual foot with respect to the floor is determined.
The posture is shifted, and as a result, the actual foot floor reaction force deviates from the target angle foot floor reaction force. In order to cancel this shift, the shift of the position / posture of the actual foot caused by the tilting of the body is determined by the two-leg compensation angle θdbv and the foot compensation angles θnx, θnx.
It may be canceled by correcting ny.

Specifically, correction is performed using the X component θerrx and the Y component θerry of the inclination deviation of the body and the vector V as follows. That is, a value obtained by adding Δθdbv of the following equation to the two-leg compensation angle θdbv obtained by the above-mentioned two-leg compensation angle determination method is set as the two-leg compensation angle θdbv. Δθdbv =-(θerrx * Vx + θerry * Vy)

The first foot X compensation angle θ1x is obtained by subtracting θerrx from the first foot X compensation angle θ1x and the second foot X compensation angle θ2x obtained by the above-described foot foot compensation angle determination techniques. , The second foot X compensation angle θ2x.

Similarly, the first foot Y compensation angle θ1y is obtained by subtracting θerry from the first foot Y compensation angle θ1y and the second foot Y compensation angle θ2y obtained by the respective foot compensation angle determination methods. , The second foot Y compensation angle θ2y. The claims 10 and 13 are based on this description.

In the first to third embodiments, when it is not necessary to increase the control accuracy,
The two-leg mechanism deformation compensation angle θffdbv may be zero. That is,
The calculation of the mechanism deformation compensation angle may be omitted.

In the first to third embodiments, when it is not necessary to increase the control accuracy,
The first foot X mechanism deformation compensation angle θff1x may be zero. That is, the calculation of the mechanism deformation compensation angle may be omitted.

In the first to third embodiments, the weighting variable for distribution is determined according to the timing of the desired gait, so that the processing is simple. However, when the actual floor condition is significantly different from the floor assumed by the target gait, the landing timing may be shifted, so that the amount of increase in the actual floor reaction force may be largely deviated from Mdmd.

In order to increase the robustness against unexpected changes in the floor surface condition, it is possible to detect the moment of landing and leaving the floor from the force component of the actual floor reaction force, and use this as a trigger to change the distribution weight variable. good.

Also, the foot contact state (for example, whether each foot actual floor reaction force center point is out of a desired contact area) is estimated from the actual foot floor reaction force, and if the contact state is not good. For example, the value of the weight variable for distribution may be appropriately changed in consideration of actual foot floor reaction force, such as reducing the weight to suppress the generation of a moment.

In the first to third embodiments, the equations for the inverse kinematics solution are directly obtained, and the body position / posture and the foot position / posture are substituted into the equations. To obtain the displacement of each joint. In these embodiments, there is a solution, but depending on the arrangement of joints, there may be no direct solution, and in such a case, it cannot be used.

In this case, an inverse Jacobian or a pseudo inverse Jacobian expressing a ratio of a perturbation of the joint relative to a perturbation of the relative position / posture of the foot with respect to the body position / posture in a matrix form is used to approximate each joint. The displacement may be obtained.
This is a technique often used in ordinary industrial robots and the like. Even if the above method cannot be used, with this method,
The solution can be obtained approximately.

In the first to third embodiments, the spring mechanism 32 (and the sole elastic body 34) is not an essential part of the present invention. The essence of the present invention lies in the feedback control part, and the mechanism deformation compensation is incidental.

In the above-described first to third embodiments, the block diagrams may be subjected to equivalent deformation such as changing the order of arithmetic processing.

In the first to third embodiments, as described above, it is assumed that the desired gait receives a reaction force (target object reaction force) other than the floor reaction force from the environment. The target ZMP is defined dynamically by calculating the resultant of the inertial force, gravity generated by the target motion pattern, and the reaction force of the target object, and the moment acting on a certain point on the floor surface is about the vertical axis. If the value is zero except for the component, the point may be set as the target ZMP again.

The present applicant has disclosed in Japanese Patent Application Laid-Open No. 5-33784.
In Publication No. 9, the target total floor reaction force center point is left as it is,
A method is proposed in which only the target movement pattern is corrected, and the ZMP of the corrected target movement pattern and the target total floor reaction force center point are shifted to restore the posture inclination. When that method is used together, the desired total floor reaction force center point does not match the desired ZMP.

Although the present invention has been described with respect to a bipedal walking robot, the present invention can be applied not only to a bipedal walking robot but also to a multi-legged robot.

[0303]

According to the first aspect, the floor reaction force acting on the legged mobile robot can be easily and appropriately controlled without causing interference. In other words, even if control similar to the combination of the previously proposed two-leg compliance control and ankle compliance control is performed, there is no control interference, and the actual total floor reaction force and the actual foot floor reaction force deviate from desired values or oscillate. Never do.

That is, in addition to global undulations and slopes,
Even if there is an unexpected floor shape change including local unevenness or inclination, the floor reaction force acting on the legged mobile robot can be appropriately controlled without being greatly affected by the unexpected change.

Further, the posture stabilization control of the legged mobile robot can be easily realized, the landing impact received by the legged mobile robot can be reduced, the grounding property of the legged mobile robot can be improved, and the slip during walking can be improved. And spin can be prevented. Further, the load on the actuator of the legged mobile robot can be reduced.

According to the second aspect, the same function and effect as the first aspect can be obtained.

According to the third aspect, the same function and effect as those of the first aspect can be obtained, and the floor reaction force can be more appropriately controlled.

According to the fourth aspect, the same operation and effect as those of the first aspect can be obtained, and the total floor reaction force, which is particularly important for attitude control, can be more appropriately controlled.

According to the fifth aspect, the same function and effect as those of the first aspect can be obtained and the posture stabilizing ability can be improved.

[0310] According to the sixth aspect, the same operation and effect as described above can be obtained, and the posture stabilizing ability can be further improved.

According to the seventh aspect, the same operation and effect as described above can be obtained, the spin or slip of the robot can be prevented, and the posture stabilizing ability can be further improved. Therefore, even when walking on a road surface having a low coefficient of friction, spin or slip can be effectively prevented, and walking can be continued in a stable posture.

According to the eighth aspect, the same operation and effect as described above can be obtained, and walking can be continued in a stable posture along the target route.

According to the ninth aspect, the same operation and effect as described above can be obtained, and the spin or slip of the robot can be prevented to a considerable extent without detecting the yaw rate. In that sense, the posture stabilizing ability can be further improved.

According to the tenth aspect, the same operation and effect as described above can be obtained, and the actual floor reaction force acting on the robot can be more accurately controlled.

According to the eleventh aspect, the same operation and effect as described above can be obtained, the load on the plurality of legs can be appropriately distributed, and the friction distribution with the floor surface is locally reduced. Does not have an excessive effect on Therefore, the grounding performance can be further improved, and the spin or the slip can be further avoided.

According to the twelfth aspect, the same operation and effect as those of the first aspect can be obtained, and the correction amount of the foot can be more appropriately distributed. Greater restoring force and higher groundability can be obtained.

According to the thirteenth aspect, the same function and effect as those of the twelfth aspect can be obtained, and the actual floor reaction force acting on the robot can be more accurately controlled.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing an overall control device of a legged mobile robot according to the present invention.

FIG. 2 is an explanatory side view showing a structure of a foot of the bipedal walking robot shown in FIG. 1;

FIG. 3 is a block diagram showing details of a control unit of the bipedal walking robot shown in FIG. 1;

FIG. 4 is a block diagram functionally showing the configuration and operation of a control device for a legged mobile robot according to the present invention.

FIG. 5 is an explanatory diagram showing an example of a movement pattern when the legged mobile robot shown in FIG. 1 walks on flat ground.

6 is an explanatory diagram illustrating a locus on the floor surface of a locus of a desired total floor reaction force center point (a desired ZMP) corresponding to the motion pattern of FIG. 5;

FIG. 7 is a time chart of a target total floor reaction force center point (target ZMP) trajectory corresponding to the motion pattern of FIG. 5;

8 is a time chart of a target first floor floor reaction force center point trajectory set so as to satisfy a predetermined condition corresponding to the exercise pattern of FIG. 5;

9 is a time chart of a desired second foot floor reaction force center point trajectory set so as to satisfy a predetermined condition corresponding to the exercise pattern of FIG. 5;

FIG. 10 is a flowchart showing the operation of the control device for a legged mobile robot according to the present invention, similarly to FIG. 4;

FIG. 11 is a flowchart for explaining the operation of the composite compliance operation determining unit shown in FIG. 4 for performing arithmetic processing such as a double leg compensation angle in the flow chart of FIG. 10;
It is explanatory drawing which shows the situation in which each foot floor reaction force acts on a foot and a 2nd foot.

12 is an explanatory diagram showing setting of a desired total floor reaction force in the situation shown in FIG. 11;

13 is an explanatory diagram showing distribution of target foot floor reaction forces in the situation shown in FIG. 11;

FIG. 14 is an explanatory diagram showing a compensating total floor reaction force moment in the situation shown in FIG. 11;

15 is an explanatory diagram showing a normal vector V on a plane that includes each foot floor reaction force center point and that is perpendicular to the horizontal plane in the situation shown in FIG. 11;

FIG. 16 is an explanatory diagram showing a state in which each desired foot floor reaction force central point is rotated by a predetermined angle θdbv around a desired total floor reaction force central point (target ZMP) in the situation shown in FIG. 11; .

FIG. 17 shows a state in which each foot is rotated by a predetermined angle θnx, θny around a longitudinal axis and a lateral axis in the situation shown in FIG.
FIG. 4 is an explanatory diagram showing a state in which only rotation is performed.

FIG. 18 is a block diagram illustrating an operation process of a composite compliance operation determination unit in FIG. 4;

FIG. 19 is a block diagram showing a calculation process of the compensating total floor reaction force moment distributor shown in FIG. 18;

20 is a time chart showing an example of setting distribution weight variables for operating the two-leg compensation angle and the like of the compensating total floor reaction force moment distributor shown in FIG. 18;

21 is an explanatory diagram showing a posture of the robot for explaining setting of distribution weight variables of the compensating total floor reaction force moment distributor of FIG. 20;

FIG. 22 is an explanatory diagram showing a posture of a robot for explaining setting of a distribution weight variable of the compensating total floor reaction force moment distributor, similarly to FIG. 21;

FIG. 23 is an explanatory diagram showing a two-leg compensation moment V-direction component Mdmdbbv when distribution weights for operating the two-leg compensation angle are determined under predetermined conditions.

FIG. 24 is a block diagram illustrating a calculation process of a two-leg compensation angle determination unit illustrated in FIG. 18;

25 is a block diagram illustrating a calculation process of a compensation angle determination unit for each foot shown in FIG. 18;

26 is an explanatory diagram for describing the arithmetic processing of the corrected target foot position / posture calculation unit with mechanical deformation compensation shown in FIG. 18;

27 is an explanatory diagram similar to FIG. 26, illustrating the calculation processing of the corrected target foot position / posture calculation unit with mechanism deformation compensation shown in FIG. 18;

FIG. 28 is a subroutine flowchart showing a work of determining a leg compensation angle and the like in the flowchart of FIG. 10;

FIG. 29 is an explanatory view similar to FIG. 16 showing the second embodiment of the present invention, and is an explanatory view showing another example of a foot position correcting operation.

FIG. 30 shows a device according to a third embodiment, FIG.
FIG.

FIG. 31 shows an apparatus according to a third embodiment,
It is a flow chart similar to.

FIG. 32 is an explanatory top view illustrating route guidance planned by the device according to the third embodiment.

FIG. 33 shows the operation of the device according to the third embodiment.
FIG. 17 is an explanatory diagram similar to FIG. 16.

FIG. 34 shows the operation of the device according to the third embodiment.
It is explanatory drawing similar to FIG.

FIG. 35 is a block diagram, similar to FIG. 18, showing the arithmetic processing of the composite compliance operation unit of the device according to the third embodiment.

FIG. 36 is a block diagram illustrating a calculation process of a Z-component compensation moment determination unit in FIG. 35;

FIG. 37 is a block diagram showing a calculation process of the compensating total floor reaction force moment distributor shown in FIG. 36.

FIG. 38 is a time chart showing a setting example of distribution weight variables of the compensating total floor reaction force moment distributor shown in FIG. 37.

FIG. 39 is a subroutine flow chart showing a work of determining a leg compensation angle around the Z-axis in the flow chart of FIG. 31;
It is a chart.

FIG. 40 is an explanatory diagram when the bipedal walking robot walks on an unexpected slope.

FIG. 41 is an explanatory diagram in the case where the previously proposed double-legged compliance control is performed on the bipedal walking robot shown in FIG. 40;

FIG. 42 is an explanatory view similar to FIG. 40, when a bipedal walking robot steps on an unexpected projection.

FIG. 43 is an explanatory diagram when the previously proposed ankle compliance control is performed in the situation shown in FIG. 42;

[Explanation of symbols]

Reference Signs List 1 bipedal walking robot (legged mobile robot) 2 leg link 10, 12, 14R, L hip joint 16R, L knee joint 18, 20R, L ankle joint 22R, L foot (foot) 24 upper body 26 control unit 32 spring mechanism 34 sole elastic body 44 6-axis force sensor 60 inclination sensor

Claims (13)

[Claims] 1. A leg comprising at least a base and a plurality of legs having a foot connected to the base via a first joint and connected to a distal end of the base via a second joint. A control device for a mobile robot, comprising: a. Gait generating means for generating a gait of the robot including at least a movement pattern including a target position and a posture of the foot of the robot and a target pattern of a total floor reaction force acting on the robot; b. A desired foot floor reaction force center point that determines a desired foot floor reaction force center point as an action center point on the foot when the generated total floor reaction force of the gait is distributed to each of the feet. Determining means, c. Actual floor reaction force detecting means for detecting an actual floor reaction force acting on the foot; d. The detected actual floor reaction force calculates a moment acting around the calculated target foot floor reaction force central point, and determines a rotation amount for rotating the foot based on at least the calculated moment. Foot rotation amount determining means; e. Foot position / posture correction means for correcting the target position and / or posture so that the position and / or posture of the foot is rotated based on the determined foot rotation amount; and f. A joint displacement means for displacing the first and second joints of the robot based on the corrected position and posture of the foot, and a control device for the legged mobile robot. 2. A leg comprising at least a base and a plurality of legs having a foot connected to the base via a first joint and having a tip connected to the distal end via a second joint. A control device for a mobile robot, comprising: a. Gait generating means for generating a gait of the robot including at least a movement pattern including a target position and a posture of the foot of the robot and a target pattern of a total floor reaction force acting on the robot; b. A desired foot floor reaction force center point that determines a desired foot floor reaction force center point as an action center point on the foot when the generated total floor reaction force of the gait is distributed to each of the feet. Determining means, c. Actual floor reaction force detecting means for detecting an actual floor reaction force acting on the foot; d. Foot rotation amount determining means for determining a rotation amount for rotating the foot based on at least the detected actual floor reaction force; e. The target position and / or posture is such that the position and / or posture of the foot is rotated around the determined target foot floor reaction force center point or the vicinity thereof based on the determined foot rotation amount. Foot position / posture correction means for correcting the posture; and f. A joint displacement means for displacing the first and second joints of the robot based on the corrected position and posture of the foot, and a control device for the legged mobile robot. 3. The foot position / posture correcting means, based on the determined foot rotation amount, determines a position and / or a position of the foot.
2. The legged movement according to claim 1, wherein the target position and / or posture is corrected such that the posture rotates around or near the determined target foot floor reaction force center point. 3. Robot control device. 4. Further, g. Either the total floor reaction force moment actually acting on the robot or the moment obtained by subtracting the floor reaction force moment acting on the foot from the total floor reaction force moment actually acting on the robot is calculated. A foot moving amount determining means for determining a moving amount for moving the foot at least according to the calculated moment, wherein the foot position / posture correcting means includes the determined foot rotation amount and The control device for a legged mobile robot according to any one of claims 1 to 3, wherein the position and / or posture of the foot is corrected based on the determined movement amount. 5. A posture stabilizing compensation total floor reaction force moment to be added to the total floor reaction force target pattern, and the foot rotation amount determining means and / or the foot movement amount determining means determine at least the detection amount. The rotation amount and / or the movement amount of the foot are determined based on the actual floor reaction force obtained and the determined posture stabilization compensation total floor reaction force moment. A control device for a legged mobile robot according to any one of the first to third aspects. 6. The legged mobile robot according to claim 1, wherein the posture stabilization compensation total floor reaction force moment is obtained based on at least a tilt deviation of the robot. Control device. 7. The control of a legged mobile robot according to claim 1, wherein the posture stabilization compensation total floor reaction force moment is obtained based on at least a yaw rate of the robot. apparatus. 8. The leg system according to claim 1, wherein the posture stabilization compensation total floor reaction force moment is obtained based on at least a deviation from a target path of the robot. Control device for mobile robot. 9. The legged movement according to claim 1, wherein a predetermined component in the posture stabilization compensation total floor reaction force moment is set to zero or near zero. Robot control device. 10. The method according to claim 1, wherein the foot position / posture correcting means further corrects the target position and / or posture based on a posture deviation of the robot. A control device for a legged mobile robot as described in the above. 11. The foot rotation amount determination means and / or the foot movement amount determination means, wherein the posture stabilization compensation total floor reaction force moment is distributed to each of the plurality of legs. The control device for a legged mobile robot according to any one of claims 5 to 10, wherein the amount of rotation and / or the amount of movement of the foot is determined. 12. A leg comprising at least a base and a plurality of legs having a foot connected to the base via a first joint and connected to a distal end of the base via a second joint. A control device for a mobile robot, comprising: a. Gait generating means for generating a gait of the robot, comprising a motion pattern including at least a target position and a posture of the foot of the robot and a target trajectory pattern of a total floor reaction force acting on the robot; b. Posture stabilization compensation total floor reaction force calculating means for calculating a compensation total floor reaction force for stabilizing the posture of the robot; c. Foot actual floor reaction force detecting means for detecting an actual floor reaction force acting on the foot, d. Floor reaction force distribution means for distributing the total floor reaction force of the desired gait and the compensation total floor reaction force; e. Correcting means for correcting the position and / or posture of the foot of the target gait based on the distributed floor reaction force, the compensated floor reaction force, and the detected actual foot reaction force of the distributed desired gait; and f. A joint displacement control means for controlling displacement of the first and second joints of the robot based on the corrected target foot position and posture. 13. The legged mobile robot according to claim 12, wherein said correcting means further corrects the position and / or posture of a foot of said target gait based on a posture deviation of said robot. Control device.