JP5286878B2 - Mobile robot movement control method and mobile robot - Google Patents

Description

  The present invention relates to a mobile robot movement control method and a mobile robot. Specifically, the present invention relates to a movement control method and a mobile robot for a mobile robot that autonomously walks or travels on two legs.

Development of humanoid legged robots (bipedal walking robots) that autonomously walk on two legs is underway. Such a legged robot generates a walking trajectory while setting the target ZMP to a position that stabilizes the posture, and executes motion control of each joint to perform walking based on the generated trajectory.
Here, unlike a crawler-type moving body, a legged robot realizes walking movement by repeating landing and leaving movements of two legs. Therefore, the reaction force from the floor surface is applied as an impact to the legs and the entire robot at the time of landing, and the excessively strong impact causes damage and failure of the actuators and other components constituting the joint. .

Therefore, Patent Document 1 discloses a control method for reducing the impact received from the floor surface when landing.
Patent Document 1 describes a legged mobile robot. In this legged mobile robot, a joint is constituted by an actuator with variable impedance, and when the leg leaves the floor, the impedance of the joint actuator is lowered, and the joint is landed with the joint impedance lowered. Then, at the time of landing, the joint actuator functions as a cushioning material, and the impact at the time of landing is reduced. Then, after landing, the reduced impedance is restored.

JP 2001-138273 A

  However, if the gain of the joint actuator is lowered by lowering the impedance of the joint actuator when landing on the leg, landing impact absorption can be surely made, but the joint drive angle tends to deviate from the target value due to the lower joint gain. Become. For example, the weight of the robot itself cannot be sufficiently supported and the center of gravity sinks too much, or the robot becomes weak against disturbance, so that a deviation (deviation) from the target value is likely to occur. If a deviation from the target value occurs when landing, if the actuator gain is returned to the original value in response to the landing detection as in Patent Document 1, a sudden posture change occurs and the robot becomes unstable. End up.

Here, there is also an idea that a timing of returning the impedance (gain) of the joint actuator is slowed to avoid a sudden posture change.
However, in this case, since the next step is drawn out and landed in a state where the deviation (deviation) from the target value remains, the deviation from the target value accumulates and becomes large. And if the shift | offset | difference of the assumed floor surface and an actual floor surface becomes large too much, problems, such as hitting a leg against a floor surface and falling down, will arise.

  An object of the present invention is to provide a mobile robot movement control method and a mobile robot that stably perform a smooth movement operation.

  The movement control method for a mobile robot according to the present invention is a mobile robot movement control method for controlling a movement operation of a biped mobile robot that autonomously performs movement by alternately switching free legs and support legs. A moving operation execution step for executing an operation for one step from the time when the leg is released to the time when the leg is swung in the moving direction and the landing is performed, and the next movement operation executing step is performed while the operation for one step is performed by the moving operation execution step. A recalculation step of recalculating the trajectory of the movement in the next movement operation execution step until the leg is swung out, and the recalculation step is performed after one step of the movement in the movement operation execution step. A center-of-gravity position shift calculating step for calculating a position shift between the target center-of-gravity position and the actual center-of-gravity position; a center-of-gravity position update step for updating the target center-of-gravity position based on the actual center-of-gravity position; The updated updated centroid position in the new process, based on, characterized in that it comprises a trajectory calculation step of calculating the trajectory of the moving operation performed in the next movement operation execution step.

  In such a configuration, the trajectory of the operation in the next moving operation execution step is recalculated by the recalculation step while the moving operation is being executed in the moving operation execution step. Then, the next one-step operation is executed based on the recalculated trajectory. In this way, the recalculation of the trajectory that allows the next operation to proceed smoothly and smoothly is performed, so that a stable moving operation can be always continued.

The landing position may be deviated from the target or the posture may be deviated from the target due to the influence of the dead weight or disturbance when landing the free leg by performing a one-step movement.
Conventionally, when a deviation from the target occurs in this way, a correction command corresponding to the deviation is issued to return to the target trajectory. In this case, when the deviation is large, a large torque is applied according to the deviation, and a steep movement may occur. If the deviation is large, the movement becomes steep and the balance may be lost and fall down, or it may not be able to return to the target trajectory and become uncontrollable, and the subsequent walking motion may not be continued.

  In this regard, in the present invention, after the one-step operation (moving operation execution step), the actual center-of-gravity position is confirmed, the center-of-gravity position is newly updated, and the condition for calculating the trajectory of the next one-step operation is changed. Then, even if the center of gravity trajectory is shifted due to a disturbance or the like, the next operation is continuously and smoothly shifted to continue the stable operation. As a result, it is possible to avoid a situation in which control is lost due to a steep operation or a cumulative deviation.

  In the present invention, the recalculation step includes a joint angle deviation calculating step of calculating an actual joint angle with respect to a target joint angle, and a joint angle target so that the joint angle deviation is reduced. It is preferable to provide a target joint angle changing step for changing the value.

In such a configuration, the angle deviation from the target is calculated in the joint angle deviation calculating step, and the target value is changed by accepting the deviation of the joint angle to some extent in the target joint angle changing step.
Thus, by correcting the shift of the joint angle, it is possible to correct the shift of the landing position and smoothly shift to the next operation.

Here, after changing the target value of the joint angle in the target joint angle changing step, it is preferable to increase the gain of the actuator constituting the joint to set the joint angle to the target value.
According to such a configuration, the deviation from the target is eliminated and the control is stabilized.
Note that the speed at which the gain is increased is preferably set in accordance with the magnitude of the deviation between the actual angle and the target value. For example, when the deviation is large, the gain may be gradually returned (increased), and when the deviation is small, the gain may be promptly returned (increased).

Here, when changing the target value of the joint angle, it is preferable to set a deviation limit value in which the target is not changed by changing the target when the angle deviation exceeds a certain limit value.
For example, if the limit value of this deviation is set to 2 °, when the target value of the angle at a certain joint is 50 °, it is actually 48 °. The value setting is not changed, and the target value is maintained at 50 °.
If it is a slight deviation, it can be corrected to the target trajectory by a normal correction operation. In such a case, the original target is maintained and placed on the target trajectory.
In addition, it is preferable to set an upper limit for changing the target angle at a time.
For example, if the upper limit amount to be changed is set to 5 °, when the target angle value is 50 ° at a certain joint, it is actually 40 ° and the angle deviation is 10 °. The target value is changed and the target value is set to 45 ° in this example.
If all angle deviations are accepted and the angle target is changed, the correction becomes excessive, and the disadvantage of being too affected by disturbances and maintaining the balance of the movement is avoided. it can.

  In the present invention, it is preferable that the moving operation execution step includes a free leg joint gain lowering step of lowering the gain of the joint of the free leg before landing the free leg.

In such a configuration, since the gain of the free leg is lowered before landing, the impact during landing can be mitigated.
Here, if the gain of the free leg is lowered and the robot is made to land, problems such as excessive sinking due to its own weight or being easily affected by disturbance are likely to occur. Since the next one-step operation is performed based on the calculated trajectory, the moving operation can be continued smoothly even if there is an influence of sinking or disturbance due to its own weight.
As a result, it is possible to achieve an epoch-making effect that a smooth movement operation can be performed while mitigating the impact of landing.

  In the present invention, the trajectory calculation step includes a relative ZMP update step of setting and updating a relative ZMP in a direction opposite to the center of gravity misalignment direction according to the center of gravity misalignment calculated in the center of gravity misalignment calculating step. It is preferable to provide.

In such a configuration, by shifting the relative ZMP in the direction opposite to the direction in which the center of gravity shift occurs, the center of gravity shift during the moving operation can be further reduced, and the operation along the target trajectory can be performed.
As a result, the movement operation can be further stabilized.
The relative ZMP trajectory is the time-dependent data of the position of the target ZMP with respect to the reference point of the foot of the supporting leg, and the robot is stable if the ZMP exists in the foot of the supporting leg in the ground contact phase.
Here, for example, when the center of gravity shifts behind the target during the moving operation, the relative ZMP position is adjusted (for example, shifted forward) so that the center of gravity shift does not occur, and the moving operation is further performed. It can be stabilized.

  In the present invention, in the trajectory calculation step, the rotational momentum for rotating the body posture in the direction opposite to the direction of the center of gravity misalignment according to the center of gravity misalignment calculated in the center of gravity misalignment calculating step is calculated. It is preferable to include an upper body posture adjustment step to be added.

According to such a configuration, since the body posture is adjusted, the moving operation can be continued with an appropriate posture.
In the present invention, when a shift in the center of gravity occurs, the position of the center of gravity is updated according to the actual position.
In this respect, the posture can be stabilized by incorporating the rotational momentum for properly returning the body posture into the trajectory calculation.

  In the present invention, the trajectory calculation step adds to the trajectory calculation a motion for rotating the foot in the direction opposite to the direction of the center of gravity misalignment according to the center of gravity misalignment calculated in the center of gravity misalignment calculating step. It is preferable to provide a foot angle adjusting step.

  According to such a configuration, the foot can be made to follow the floor surface, and the robot can be further stabilized.

  The mobile robot of the present invention is a two-legged mobile robot that autonomously performs the movement by alternately switching the free leg and the support leg, and after leaving the free leg, it swings out in the moving direction and is landed. And a recalculation unit that recalculates the trajectory of the motion in the next one step during execution of the one step operation, and the recalculation unit includes one step A center-of-gravity position shift calculating unit that calculates a position shift between the target center-of-gravity position and the actual center-of-gravity position after the operation; a center-of-gravity position update unit that updates the target center-of-gravity position based on the actual center-of-gravity position; A trajectory calculation unit that calculates a trajectory of a moving operation to be executed in the next moving operation on the basis of the updated barycentric position updated by the position updating unit.

  According to such a configuration, it is possible to achieve the same effects as the above-described invention. In other words, since the trajectory calculation that allows the next operation to proceed smoothly and smoothly is performed, a stable moving operation can always be continued.

  According to the present invention, since the condition for calculating the trajectory of the next one-step motion is changed by newly updating the center of gravity position while confirming the actual center of gravity position, even if the center of gravity trajectory is shifted due to a disturbance or the like, Stable walking can be continued by making a smooth transition to the next motion.

The best mode for carrying out the present invention will be described below with reference to the drawings.
A first embodiment of the mobile robot movement control method of the present invention will be described.
FIG. 1 is a diagram illustrating an appearance of the mobile robot 100.
In the mobile robot 100, a left leg link 200 and a right leg link 300 are provided on a trunk 110 so as to be swingable via a hip joint 130.
The leg links 200 and 300 are also provided with joint portions including a knee joint portion 410, an ankle joint portion 420, and a toe joint portion 430.
Each joint of the mobile robot 100 includes an actuator (not shown), and each actuator is driven and controlled by the control unit 120 built in the trunk 110. That is, the control unit 120 stores a function unit that executes each step described later, and realizes the movement control method of the present invention.
The mobile robot 100 is provided with sensor means (not shown) constituted by an imaging camera or laser transmission / reception means. Then, based on the information acquired by the sensor means, surrounding environment information (environment map) and self-location information are simultaneously recognized by the control unit.
Based on the environmental map information and the self-location information, the control unit autonomously plans a moving operation and gives a control command to each actuator to realize a walking operation (moving operation).

Next, a mobile robot movement control method according to the present embodiment will be described with reference to a flowchart.
FIG. 2 is a flowchart showing the overall configuration of the mobile robot movement control method.
First, the mobile robot movement control method according to the present embodiment includes an initial setting step (ST100) and a walking motion execution step of performing a one-step motion from the time when the free leg is left to the time when it is swung out in the moving direction to be landed. (Moving motion execution step) (ST200) and a recalculation step (ST300) for recalculating the trajectory of the motion in the next walking motion execution step.
Hereinafter, it demonstrates in order.

FIG. 3 is a flowchart showing the procedure of the initial setting step (ST100).
In the initial setting step (ST100), first, initial conditions are read (ST110).
This is a step of reading initial conditions and initial settings input in advance by the operator.
Examples of initial conditions given by the operator include movement modes such as running or walking, movement speed, relative ZMP trajectory, end conditions (duration or movement distance), and the like.

When the operation mode is traveling, there is an aerial phase in which both legs float in the air.
When the operation mode is walking, the free leg and the support leg are alternately switched between the right leg 300 and the left leg 200, and the ground phase is continuous without interposing the aerial phase therebetween. In this embodiment, walking will be described as an example.

  The moving speed can be given as the horizontal speed of the center of gravity of the mobile robot 100. The relative ZMP trajectory is data with time of the position of the target ZMP with respect to the reference point of the foot of the support leg. For example, the relative ZMP trajectory can be set to be fixed at the center of the foot of the support leg. Alternatively, a trajectory that moves from the rear to the front inside the foot of the support leg may be set.

  Next, the calculation of the initial trajectory is executed, and the relative trajectory of the center of gravity from the start of the operation to the landing at the several steps (for example, the second step) is calculated (ST120). The relative trajectory of the center of gravity is calculated so that the actual ZMP matches the trajectory of the target ZMP under the horizontal speed of the center of gravity given as an initial condition.

Next, the angles of the joints that realize the relative trajectory of the center of gravity calculated in ST120 are calculated (ST130). This can be obtained by solving the Jacobian equation relating the velocity (q ′) of the center of gravity and the velocity (θ ′) of each joint.
When the motion (joint angle) to be realized is obtained in this way, the initial setting step (ST100) is terminated, and the process proceeds to the next walking motion execution step (ST200).

FIG. 4 is a flowchart showing the procedure of the walking motion execution step (moving motion execution step) (ST200).
In the walking motion execution step (ST200), first, the motion (joint angle) to be realized is read to start the walking motion (ST210), and the leg set as a free leg is lifted by leaving the floor (see FIG. 5).
In the stage where one leg is in the standing state, the gain of the actuator constituting the joint of the leg is increased to the maximum value within the setting conditions.
The legs here are both free legs and standing legs, and maximize the gain of the joints of both legs.
In this state, the swing leg is swung in the moving direction and driven toward the landing position (ST220) (see FIG. 6).

Then, the gain of the actuator constituting the joint of the free leg is lowered immediately before the free leg reaches the landing position (ST230). The joints that lower the gain may be only the joints 420 and 430 at the end portions that are the ankles and toes of the free leg. Alternatively, the gain of the knee joint 410 may be lowered instead of the joint at the end portion. Alternatively, the gain of all joints of the free leg including the end portion and the knee joint may be lowered. The degree of gain to be lowered can be set as appropriate within a range in which attitude control is maintained.
For example, the maximum value is about 20% to 50%.

In this way, the free leg is landed with the joint gain of the free leg lowered (ST240) (see FIG. 7). Then, the impact at the time of landing is relieved, a smooth walking motion is achieved, and the legs 200 and 300 and the trunk 110 are prevented from being damaged. Then, the ZMP is moved into the foot of the leg that has landed as a free leg, and the free leg and the support leg are switched (ST250).
This completes one step of the walking motion and starts the recalculation step (ST300).

FIG. 8 is a flowchart showing the procedure of the recalculation step (ST300).
In the recalculation step (ST300), first, current data is acquired (ST310). That is, actual angle data of each joint is acquired.
In the present embodiment, in the above-described walking motion execution step (ST200), the joint gain of the free leg is lowered immediately before the free leg is landed (ST230). As a result, the impact at the time of landing is mitigated, but at the same time, the free leg sinks too much due to the weight of the robot itself, or the robustness to disturbance is reduced. For this reason, the actual joint angle is likely to deviate from the target joint angle.
For example, when a disturbance from the front to the rear acts, the mobile robot 100 tilts backward as shown in FIG. Therefore, after obtaining the actual joint angle (ST310), the present state data is compared with the target joint angle to calculate the shift of the joint angle (ST320).

When the deviation of the joint angle is obtained in this way (ST320), the target value is changed according to the deviation of the joint angle (ST330).
When the deviation (deviation) from the target value of the joint angle is obtained in ST320, the target value of the joint angle is changed so as to reduce the angular deviation (ST330).

Here, when the target value of the joint angle is changed, a deviation limit value that does not change the target is set so that the target is changed when the angle deviation exceeds a certain limit value.
For example, if the limit value of this deviation is set to 2 °, when the target value of the angle at a certain joint is 50 °, it is actually 48 °. The value setting is not changed, and the target value is maintained at 50 °.
On the other hand, when the target value of the joint angle at a certain joint is 50 °, it is actually 46 °, and when the angle deviation is 4 °, the setting of the target value is changed so as to reduce the angle deviation. Set the target value to 46 °.

Moreover, the upper limit of the amount changed at once is set.
For example, if the upper limit amount to be changed is set to 5 °, when the target angle value is 50 ° at a certain joint, it is actually 40 ° and the angle deviation is 10 °. The target value is changed and the target value is set to 45 ° in this example.

In ST340, the gain of the support leg is returned.
In ST230, when the gain of the leg joint is lowered before landing in ST230, the lowered gain is returned to drive toward the newly set joint angle target value.
At this time, the gain of the joint having a small difference between the current state and the target value is quickly returned, and the gain of the joint having a large difference between the current state and the target is slowly returned.
For example, when the target value of the joint angle is set and changed in ST330, the speed at which the gain is returned is changed in accordance with the amount of change.

Next, in ST350, the gravity center shift is calculated. That is, the deviation of the actual center of gravity position with respect to the target center of gravity center calculated in ST120 is obtained.
As the joint angle, the state of the mobile robot 100 is grasped based on the joint angle setting target changed in ST330, the center of gravity position of the mobile robot 100 is obtained, and the deviation (deviation) from the target trajectory is calculated.
The deviation of the center of gravity is obtained as a rotation angle Δθ centered on the joint at the end of the leg (for example, the joint at the toe) (see FIG. 10). In ST360, the gravity center position is updated based on the actual gravity center position.
Here, when updating the center of gravity position, the target center of gravity position may be updated so that the target center of gravity position and the actual center of gravity position coincide with each other, or the target center of gravity position is updated so as to reduce the center of gravity position deviation. May be. For example, the target centroid position may be set and updated so that the centroid position deviation is reduced by 50%. If the center-of-gravity position shift is eliminated to some extent, the accumulated deviation does not increase, and if the target center-of-gravity position is adjusted too much to the actual position, it may be influenced by disturbance and become unstable. Therefore, it is desirable to appropriately set how much the target barycentric position is adjusted to the actual position.

Next, in ST370, trajectory calculation is executed. That is, starting from the newly updated center of gravity position in ST360, the center of gravity trajectory and the leg trajectory for realizing the next one-step walk are calculated.
A description will be given with reference to FIG. 11 including points to be taken into consideration in the recalculation of the trajectory.

FIG. 11 is a flowchart showing the procedure of the trajectory calculation process.
In the recalculation of the trajectory, first, the deviation of the center of gravity and the updated center of gravity position are read (ST371). Next, the relative ZMP for calculating the trajectory is adjusted (ST372). The relative ZMP is input by default, and when the center of gravity of the mobile robot 100 deviates from the planned trajectory, the relative ZMP position is adjusted in order to stabilize.
For example, if the center of gravity when fixing the relative ZMP at the center of the foot is shifted behind the shifted before the relative ZMP (from P ₁ in FIG. 12 to P _2).
In this way, the relative ZMP is adjusted so as to realize stabilization by shifting the relative ZMP in the direction opposite to the direction of the center of gravity shift. As the relative ZMP position change amount, a sudden change is avoided, and for example, a change is made such that 5% to 10% of the deviation of the center of gravity is improved in one step.

Next, the body posture angle is adjusted (ST373).
When the target value of the joint angle is changed according to the shift of the joint angle (ST330), the body posture is shifted from the target value due to such a change.
For example, when the shift of the center of gravity occurs in the backward direction due to the lowering of the leg gain or the influence of the disturbance, the upper body posture of the mobile robot 100 becomes a posture warped backward rather than upright. Therefore, the body posture is brought close to the target value by adding the rotational momentum in the forward direction to the trajectory calculation (see FIG. 13). That is, according to the center-of-gravity position shift, a rotational momentum that rotates the body posture in the direction opposite to the center-of-gravity position shift direction is added to the trajectory calculation.
The rotational momentum to be added does not correct all the deviations at once, but adds a degree to improve 20% to 40% of the deviation in one step.
If the target ZMP of the mobile robot 100 is properly controlled, the effect of the deviation of the body posture on the walking stability of the mobile robot 100 is small, but from the viewpoint of the joint movable range problem and the visual impression. It is preferable to optimize the posture.

Next, the leg end angle is adjusted (ST374).
In ST373, the deviation from the target value of the body posture is added to the trajectory calculation. Separately, the deviation from the target value of the body posture is added to the target angle of the end joint. . Since it can be estimated that the mobile robot 100 is inclined with respect to the floor surface by the amount the body posture deviates from the target value, the foot is also inclined with respect to the floor surface. Therefore, the foot can be made to follow the floor by adding the inclination of the body posture to the foot angle (see FIG. 13). In other words, since the inclination of the body posture is determined according to the displacement of the center of gravity, the amount of the angle corresponding to the displacement of the center of gravity is added to the trajectory of the movement of the leg end joint to properly follow the foot floor surface. Can be.
As the leg end joint, an ankle and / or toe joint is preferable because the reaction of movement becomes fast.

  As described above, the recalculation of the trajectory is executed in ST375 in consideration of the information of ST372 to ST374. Thereby, the trajectory from the new center of gravity position to the landing of the next step is calculated.

  When the recalculation of the trajectory is completed (ST375), next, in ST380, the joint angle that realizes the calculated trajectory is calculated. Then, when the target joint angle is calculated, the recalculation step (ST300) ends.

When the termination condition (ST400) is not satisfied (ST400: NO), the walking motion is executed by returning to the walking motion execution step (ST200).
As a result, the walking motion is executed based on the newly calculated trajectory, and the walking of the mobile robot 100 proceeds by swinging out the free leg (ST220), lowering the gain before landing (ST230), and landing (ST240). The

  If the end condition is satisfied (ST400: YES), the movement control of the mobile robot 100 is ended by the end process.

As mentioned above, according to 1st Embodiment provided with such a control structure, there can exist the following effects.
(1) By the recalculation step (ST300), the next one-step operation is executed based on the recalculated trajectory. In this way, the trajectory calculation that allows the next motion to proceed smoothly and smoothly is performed, so that even if the posture tilts and the motion deviates from the target, a stable walking motion can always be continued. .

(2) The angle deviation from the target is calculated in the joint angle deviation calculating step (ST320), and the target value is changed by accepting the joint angle deviation to some extent in the target joint angle changing step (ST330). It is possible to smoothly shift to the next operation by correcting the deviation.

(3) By providing the free leg joint gain lowering step (ST230) for lowering the gain of the joint of the free leg before landing the free leg, the impact at the time of landing can be mitigated. If the gain of the swing leg is lowered and the robot is made to land, problems such as excessive sinking due to its own weight or being easily affected by disturbance are likely to occur. However, in the present invention, the recalculation step (ST300) causes a problem. Since the next one-step operation is performed based on the calculated trajectory, the moving operation can be continued smoothly even if there is an influence of sinking or disturbance due to its own weight.

(4) Since the relative ZMP updating step (ST372) for setting and updating the relative ZMP in the direction opposite to the center of gravity position deviation is provided, the deviation from the target trajectory during the moving operation can be reduced. As a result, the movement operation can be further stabilized.

(5) By including a body posture adjustment step (ST373) that adds to the trajectory calculation a rotational momentum that rotates the body posture in the direction opposite to the direction of displacement of the center of gravity, the moving operation can be continued in an appropriate posture. it can.

(6) Since it includes a foot angle adjustment step (ST374) that adds to the trajectory calculation a motion that rotates the foot in the direction opposite to the direction of displacement of the center of gravity, the foot can be made to follow the floor surface, The robot 100 can be further stabilized.

In addition, this invention is not limited to the said embodiment, The deformation | transformation in the range which can achieve the objective of this invention, improvement, etc. are included in this invention.
In the relative ZMP update step and the body posture adjustment step, when determining the adjustment amount, a cumulative value of the center of gravity deviation may be calculated, and the adjustment amount may be determined based on the cumulative value. If you try to eliminate all the previous deviations in each trajectory calculation, the correction will be too good and you may lose stability, but it will be abrupt by adjusting the predetermined percentage of the accumulated value of the deviation of the center of gravity. Correction can be avoided to maintain stability.
In the above embodiment, the walking motion has been described as an example. However, the present invention can be applied to a traveling motion with an aerial phase in between.
The control method of the present invention may be used in all sections when the mobile robot moves. However, the present invention may be employed in some sections of the movement path even if not all forms of the present invention. .
In the above embodiment, for the sake of explanation, the steps of the walking motion execution step ST200 and the recalculation step ST300 have been described serially one by one, but the walking motion execution step ST200 and the recalculation are performed in order to smoothly advance the walking motion. The process ST300 proceeds in parallel. That is, while executing the current walking motion execution step ST200, the trajectory in the next walking motion execution step is calculated in the recalculation step ST300.

It is a figure which shows the external appearance of a mobile robot. The flowchart which shows the whole structure of the movement control method of a mobile robot. The flowchart which shows the procedure of an initial setting process. The flowchart which shows the procedure of a walking operation execution process. The figure which shows a mode that the free leg left the floor in walking operation. The figure which shows a mode that the swing leg is shaken out in walking operation. The figure which shows a mode that the free leg was made to land in walking operation. The flowchart which shows the procedure of a recalculation process. The figure which shows a mode that it leaned backward by the influence of the disturbance at the time of landing. The figure for demonstrating calculation of a gravity center shift | offset | difference. The flowchart which shows the procedure of a track | orbit calculation process. The figure for demonstrating a mode that a relative ZMP is shifted and a walking posture is stabilized. The figure for demonstrating a mode that a body posture and a foot angle are adjusted.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Mobile robot, 110 ... Trunk part, 120 ... Control part, 130 ... Hip joint part, 200 ... Left leg link, 300 ... Right leg link, 410 ... Knee joint part, 420 ... Ankle joint part, 430 ... Toe joint part.

Claims (5)

In the mobile robot movement control method for controlling the movement of the biped mobile robot that autonomously performs the movement by alternately changing the free leg and the support leg,
Run the trajectory calculation to find the target trajectory,
The free leg is left in accordance with the target joint angle that realizes one step of movement according to the target trajectory, swings out in the moving direction, lowers the gain of the joint of the free leg before landing the free leg, and then the free leg is landed. Let it be a support leg,
After this landing, calculate the joint angle deviation of the actual joint angle with respect to the target joint angle,
Change the value of the target joint angle so that the joint angle deviation decreases,
Raise the gain of the support leg to the new target joint angle after changing the joint angle,
Find the center-of-gravity position deviation, which is the deviation between the actual center-of-gravity position based on the new target joint angle after the change and the center-of-gravity position of the target trajectory,
Update the target center of gravity position so that the center of gravity position deviation decreases,
A movement control method for a mobile robot, characterized in that a trajectory for realizing the next step starting from the updated target center-of-gravity position is calculated. The mobile robot movement control method according to claim 1,
In the step of updating the target center-of-gravity position so that the center-of-gravity position shift decreases,
A movement control method for a mobile robot, wherein the relative ZMP is set and updated in a direction opposite to the direction of displacement of the center of gravity. In the movement control method of the mobile robot according to claim 1 or 2,
In the step of updating the target center-of-gravity position so that the center-of-gravity position shift decreases,
A movement control method for a mobile robot, characterized by adding to the trajectory calculation a rotational momentum that rotates the body posture in the direction opposite to the direction of displacement of the center of gravity. In the movement control method of the mobile robot according to any one of claims 1 to 3,
In the step of updating the target center-of-gravity position so that the center-of-gravity position shift decreases,
A movement control method for a mobile robot, characterized in that a motion for rotating a foot in a direction opposite to the direction of displacement of the center of gravity is added to the trajectory calculation. A biped type mobile robot to perform autonomously moving by alternating the free leg and supporting leg alternately,
Run the trajectory calculation to find the target trajectory,
The free leg is left in accordance with the target joint angle that realizes one step of movement according to the target trajectory, swings out in the moving direction, lowers the gain of the joint of the free leg before landing the free leg, and then the free leg is landed. Let it be a support leg,
After this landing, calculate the joint angle deviation of the actual joint angle with respect to the target joint angle,
Change the value of the target joint angle so that the joint angle deviation decreases,
Raise the gain of the support leg to the new target joint angle after changing the joint angle,
Find the center-of-gravity position deviation, which is the deviation between the actual center-of-gravity position based on the new target joint angle after the change and the center-of-gravity position of the target trajectory,
Update the target center of gravity position so that the center of gravity position deviation decreases,
Mobile robots and calculates a trajectory to achieve the following step starting from the updated target centroid position.

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