CN111857170B - Leg joint load rule analysis method for four-foot robot - Google Patents
Leg joint load rule analysis method for four-foot robot Download PDFInfo
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- G05D1/0891—Control of attitude, i.e. control of roll, pitch, or yaw specially adapted for land vehicles
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- B62D57/02—Vehicles characterised by having other propulsion or other ground- engaging means than wheels or endless track, alone or in addition to wheels or endless track with ground-engaging propulsion means, e.g. walking members
- B62D57/032—Vehicles characterised by having other propulsion or other ground- engaging means than wheels or endless track, alone or in addition to wheels or endless track with ground-engaging propulsion means, e.g. walking members with alternately or sequentially lifted supporting base and legs; with alternately or sequentially lifted feet or skid
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Abstract
The invention relates to the technical field of intelligent robots, and discloses a method for analyzing a leg joint load rule of a quadruped robot, which comprises the following steps of: s1, controlling walking of the four-foot robot by using a spring inverted pendulum and a virtual model control algorithm; s2, adding virtual spring damping elements between ideal positions and actual positions of the respective degrees of freedom; and S3, analyzing a walking control algorithm and a load rule of the four-foot robot based on the inverted pendulum of the spring and the virtual model. The four-foot robot is subjected to forward and backward kinematics analysis by using a D-H parameter method, the relation between the foot end position and the joint rotation angle is obtained, then the four-foot robot is subjected to dynamics analysis on the basis of the kinematics analysis, the linear variable speed walking of the four-foot robot under the diagonal gait is realized by using a spring inverted pendulum and a virtual model control method, and the load rule of each joint in the diagonal gait walking process of the four-foot robot is obtained through analysis.
Description
Technical Field
The invention relates to the technical field of intelligent robots, in particular to a leg joint load rule analysis method of a quadruped robot.
Background
The quadruped robot is mainly applied to the tasks of rescue and relief work, geological exploration and the like in field complex terrains, so that the quadruped robot is required to be capable of adapting to various complex terrains, the robot adopting a wheel type, peristaltic type and other movement modes can only pass through terrains with limited unevenness, the quadruped robot is used as an important research direction of the bionic robot, is designed by imitating limb structures of mammals such as dogs, horses and the like, and can adapt to terrains with larger unevenness through scattered point contact between legs and the ground.
At present, one of the most main problems of the four-foot robot hydraulic system in the aspect of energy utilization exists: the four-foot robot hydraulic system is characterized in that the hydraulic system can simultaneously provide oil with various flow and pressure combinations under the working conditions that the same actuator is alternately high and low in speed and different actuators are simultaneously high and low in speed, and the single-pump multi-actuator hydraulic system belongs to a throttling speed regulating system, can realize flow and pressure matching only through throttling action for meeting the movement requirements of multiple actuators under multiple working conditions, and therefore generates more throttling loss. This problem results in inefficiency of the four-foot robot hydraulic system, which has severely limited the development and application of the four-foot robot technology, and therefore, energy saving research for the four-foot robot hydraulic system is necessary.
The load rule of the leg joints of the four-foot robot is the basis for developing the energy consumption research of the hydraulic system, and the load rule of the leg joints can be researched from two aspects of motion characteristics and load characteristics, so that the energy-saving research of the four-foot robot needs to be analyzed from the load rule of the leg joints of the four-foot robot.
Disclosure of Invention
Aiming at the defects of the background technology, the invention provides a leg joint load rule analysis method of a quadruped robot, which has the advantages of multi-aspect analysis and body fitting and solves the problems of the background technology.
The invention provides the following technical scheme: the leg joint load rule analysis method of the four-foot robot comprises the following steps of:
s1, controlling walking of the four-foot robot by using a spring inverted pendulum and a virtual model control algorithm;
the spring inverted pendulum mainly comprises a machine body and spring legs without mass, wherein the hip joint is arranged at the centroid of the machine body, and the spring legs can rotate around the hip joint;
s2, adding virtual spring damping elements between the ideal positions and the actual positions of the respective degrees of freedom, and pulling the machine body to track the ideal positions by utilizing virtual loads generated by the spring damping elements;
s3, analyzing a walking control algorithm and a load rule of the four-foot robot based on the inverted pendulum of the spring and the virtual model;
after the virtual model is added to the quadruped robot body, the relation among the stress, the position and the speed of the body is as follows:
(2.25)
wherein,and->The gravity center of the organism is in an absolute coordinate system>And->Direction location +.>For the height of the body's center of gravity->For the corresponding gain factor, subscript +.>Representing the expected value of the variable, +.>For pitch angle, < >>For yaw angle, after virtual force applied to the machine body is obtained, the virtual force is distributed to foot ends of supporting legs to obtain driving joint moment of the supporting legs, and here, inertial force and coriolis force effects of the four-foot robot are ignored, and only stress of the four-foot robot in static balance is considered, so that the whole stress can be known:
(2.26)
wherein,、/>、/>for the coordinates of the leg and foot ends in the machine body coordinate system, the edge of the leg and foot ends of each support leg is +.>Force in direction +.>Edge->Force in direction +.>Edge->Force in direction +.>Wherein->，/>For the body is->Virtual force in direction, ++>For the body is->Virtual force of direction, ++>For the body is->Virtual force of direction, ++>The self weight of the four-foot robot is adopted, then the Jacobian matrix is combined to obtain the driving joint moment of the supporting leg, and meanwhile, a spring inverted pendulum control algorithm is adopted to realize lateral speed control;
the process of accelerating, uniform speed and decelerating the quadruped robot from rest to rest again is called a full-motion process, the weight of the quadruped robot is equivalent to the increase of the body mass, and for convenience of research, the half load of the quadruped robot is defined as 2 times of the body mass, and the full load is defined as 3 times of the body mass;
the leg joints of the four-foot robot adopt a driving mode of a hydraulic driving unit, so that the movement and the stress of a piston rod of the hydraulic cylinder in the walking process of the four-foot robot are required to be obtained through conversion according to the structural parameters of the hydraulic cylinder at the joints;
let the elongation of the hydraulic cylinder beThe relation between the moment and angular velocity of each joint and the output and velocity of the piston rod of the hydraulic cylinder is as follows:
hip side swing joint:
(2.27)
(2.28)
hip pitch joint:
(2.29)
(2.30)
knee joint:
(2.31)
(2.32)
the moment of each driving joint of the four-foot robot is guided into formulas (2.27), (2.28), (2.29), (2.30), (2.31) and (2.32), so that the output force of a piston rod of a hydraulic cylinder in a hydraulic driving unit can be obtained, the load of the leg joint of the four-foot robot is periodically changed, the same period can be divided into two stages, the first stage is smaller in load and smaller in change amplitude, at the moment, the leg and the leg are emptied, and the leg are moved forward in a stepping mode, which can be called as a quick swing stage; the second stage is a stage in which the load is large and the variation range is large, and the leg is grounded to realize the support, and this stage is called a ground-contact support stage. In the stage of rapid swing of the legs, the legs are vacated and are stressed very little; in the leg contact supporting stage, the legs contact the ground to support the machine body, and at the moment, the legs move very little, but the actuator is stressed more. The angular velocity of each joint is led into (2.27), (2.29) and (2.31) to obtain the whole length of the hydraulic cylinder in the movement process of each joint of the robot, the displacement of each joint hydraulic cylinder can be obtained by making a difference with the corresponding initial length, and then the displacement is differentiated in time to obtain the velocity of each hydraulic cylinder;
in the simulation process, the speed of the four-foot robot is firstly increased and then is finally decreased at a constant speed. The speed and the output of the joint hydraulic cylinder can be obtained, and along with the change of the walking speed of the four-foot robot, the hip pitch joint and the knee joint show the following load rules:
(1) With the change of the walking speed of the quadruped robot, the speed of the hip pitch joint is increased firstly in the rapid swing stage and then is kept unchanged and finally is reduced in the contact support stage; the speed of the knee joint in the rapid swing stage is not changed greatly, the speed of the contact support stage is increased firstly, then kept unchanged, and finally reduced;
(2) The output force of the hip pitch joint hydraulic cylinder is increased firstly and then is unchanged and finally is reduced in a quick swing stage and a touch support stage along with the change of the walking speed of the four-foot robot; the output of the knee joint hydraulic cylinder is increased at first and then is reduced at the last after almost no change in the quick swing stage, and the output change in the touch support stage is smaller;
(3) The hip pitch joint and knee joint hydraulic cylinders have larger speed and smaller output in the quick swing stage, and the joint hydraulic cylinders have smaller speed and larger output in the ground contact supporting stage;
(4) The knee joint of the quadruped robot is used as a main output joint in the touchdown supporting stage, and the hip pitch joint is second; thus, the load rule analysis method of the leg joints of the four-foot robot is obtained.
Preferably, according to the step S3, the matrix determinant from the acting force of the foot end of the supporting leg to the virtual force is 0, so that the lateral forces of the two supporting legs are equal to realize the decomposition of the virtual force of the robot body of the quadruped robot.
Preferably, in the diagonal gait walking process of the four-foot robot, the foot end track adopts an improved cycloid track, the control method of the swing leg is similar to the machine body control method, a virtual spring damping element is added between the actual position of the foot end and the expected position, so that the foot end of the swing leg tracks an ideal track, and then ADAMS and MATLAB/Simulink combined simulation is used for realizing the diagonal gait walking control simulation of the robot, so that the change of machine body parameters in the diagonal gait advancing process of the four-foot robot is obtained.
Preferably, the spring inverted pendulum control algorithm mainly includes: the change of the leg placing position is realized by changing the grounding angle when the legs touch the ground; the body posture balance is realized by adjusting the moment of the hip joint during landing; the control of the body bouncing height is realized through the control of the main power in the recovery stage.
Preferably, the leg joint load rule of the four-foot robot mainly comprises two parts, namely a motion rule and a stress rule of a joint.
The invention has the following beneficial effects:
according to the method for analyzing the load rule of the leg joints of the four-foot robot, the forward and reverse kinematics analysis is carried out on the four-foot robot by using a D-H parameter method, the relation between the foot end position and the joint rotation angle is obtained, then the dynamics analysis is carried out on the four-foot robot on the basis of the kinematics analysis, the linear variable speed walking of the four-foot robot under the diagonal gait is realized by using a spring inverted pendulum and a virtual model control method, the load rule of each joint in the diagonal gait walking process of the four-foot robot is obtained by analysis, and meanwhile, the main characteristics of the leg joint state when the four-foot robot moves are as follows: the same leg rapid swing stage and the contact support stage are continuously switched; the rapid swing stage and the touch support stage between different legs exist at the same time; the four-foot robot has regular movement, the load characteristic of the leg joints is also regular, and the periodic switching rule of large-flow small-pressure and small-flow large-pressure energy supply is shown in the hydraulic driving unit, so that a foundation is laid for the energy saving research of the hydraulic system.
Drawings
FIG. 1 is a schematic diagram of a spring inverted pendulum model;
FIG. 2 is a schematic diagram of a robot virtual model;
FIG. 3 is a schematic diagram of the overall force applied by the robot;
FIG. 4 is a graph of a robot forward speed profile;
FIG. 5 is a graph of robot lateral velocity;
FIG. 6 is a graph of a robot roll angle;
FIG. 7 is a schematic view of a hip pitch joint and knee joint;
FIG. 8 is a schematic view of a hip lateral swing joint;
FIG. 9 is a graph of 11D articulation piston rod force output;
FIG. 10 is a graph of 12D articulation piston rod force output;
FIG. 11 is a graph of 13D articulation piston rod force output;
FIG. 12 is a graph of 11D joint piston rod displacement;
FIG. 13 is a graph of 12D joint piston rod displacement;
fig. 14 is a graph of 13D joint piston rod displacement.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Referring to fig. 1-14, a method for analyzing the load rule of the leg joints of a quadruped robot is disclosed, and the method is as follows:
s1, controlling walking of the four-foot robot by using a spring inverted pendulum and a virtual model control algorithm;
the spring inverted pendulum mainly comprises a machine body and spring legs without mass, wherein the hip joint is arranged at the centroid of the machine body, and the spring legs can rotate around the hip joint;
s2, adding virtual spring damping elements between the ideal positions and the actual positions of the respective degrees of freedom, and pulling the machine body to track the ideal positions by utilizing virtual loads generated by the spring damping elements;
s3, analyzing a walking control algorithm and a load rule of the four-foot robot based on the inverted pendulum of the spring and the virtual model;
after the virtual model is added to the quadruped robot body, the relation among the stress, the position and the speed of the body is as follows:
(2.25)
wherein,and->The gravity center of the organism is in an absolute coordinate system>And->Direction location +.>For the height of the body's center of gravity->For the corresponding gain factor, subscript +.>Representing the expected value of the variable, +.>For pitch angle, < >>For yaw angle, after virtual force applied to the machine body is obtained, the virtual force is distributed to foot ends of supporting legs to obtain driving joint moment of the supporting legs, and here, inertial force and coriolis force effects of the four-foot robot are ignored, and only stress of the four-foot robot in static balance is considered, so that the whole stress can be known:
(2.26)
wherein,、/>、/>for the coordinates of the leg and foot ends in the machine body coordinate system, the edge of the leg and foot ends of each support leg is +.>Force in direction +.>Edge->Force in direction +.>Edge->Force in direction +.>Wherein->，/>For the body is->Virtual force in direction, ++>For the body is->Virtual force of direction, ++>For the body is->Virtual force of direction, ++>The moment of a driving joint of the supporting leg is obtained by combining the dead weight of the four-foot robot and the Jacobian matrix, and meanwhile, a spring inverted pendulum control algorithm is adopted to realize lateral speed control; the main structural parameters of the quadruped robot are shown in table 2.2:
TABLE 2.2 major structural parameters for quadruped robots
In the diagonal gait walking process of the four-foot robot, the foot end track adopts an improved cycloid track, the control method of the swing leg is similar to the machine body control method, a virtual spring damping element is added between the actual position and the expected position of the foot end, the foot end of the swing leg tracks an ideal track, and then ADAMS and MATLAB/Simulink combined simulation is used for realizing the diagonal gait walking control simulation of the robot. The variation of body parameters in the diagonal gait advancing process of the quadruped robot can be finally obtained as shown in figures 4, 5 and 6;
the process of accelerating, uniform and decelerating the quadruped robot from rest to rest again is called the full motion process. The weight of the quadruped robot is increased, and the invention defines that the half load of the quadruped robot is 2 times of the mass of the machine body, and the full load is 3 times of the mass of the machine body;
the leg joints of the four-foot robot adopt a driving mode of a hydraulic driving unit, so that the movement and the stress of a piston rod of the hydraulic cylinder in the walking process of the four-foot robot are required to be obtained through conversion according to the structural parameters of the hydraulic cylinder at the joints;
the four-legged robot leg joint parameters are shown in table 2.3;
table 2.3 parameters of leg joints of quadruped robot
Let the elongation of the hydraulic cylinder beThe relation between the moment and angular velocity of each joint and the output and velocity of the piston rod of the hydraulic cylinder is as follows:
hip side swing joint:
(2.27)
(2.28)
hip pitch joint:
(2.29)
(2.30)
knee joint:
(2.31)
(2.32)
the moment of each driving joint of the quadruped robot is led into formulas (2.27), (2.28), (2.29), (2.30), (2.31) and (2.32) to obtain the output of a piston rod of a hydraulic cylinder in a hydraulic driving unit, as shown in fig. 7, 8 and 9 (taking 11D, 12D and 13D joints as examples), the load of the leg joint of the quadruped robot shows periodic variation, and the same period can be divided into two stages, namely, stage one is smaller in load and smaller in variation amplitude, at the moment, the leg and the leg are empty and move forward, which can be called as a quick swing stage; the second stage is a stage in which the load is large and the variation range is large, and the leg is grounded to realize the support, and this stage is called a ground-contact support stage. In the stage of rapid swing of the legs, the legs are vacated and are stressed very little; in the leg contact supporting stage, the legs contact the ground to support the machine body, and at the moment, the legs move very little, but the actuator is stressed more. The angular velocity of each joint is led into (2.27), (2.29) and (2.31) to obtain the whole length of the hydraulic cylinder in the movement process of each joint of the robot, the displacement of each joint hydraulic cylinder can be obtained by making a difference with the corresponding initial length, and then the displacement is differentiated in time to obtain the velocity of each hydraulic cylinder, as shown in figures 12-14;
in the simulation process, the speed of the four-foot robot is firstly increased and then is finally decreased at a constant speed. The speed and the output of the joint hydraulic cylinder can be obtained, and along with the change of the walking speed of the four-foot robot, the hip pitch joint and the knee joint show the following load rules:
(1) With the change of the walking speed of the quadruped robot, the speed of the hip pitch joint is increased firstly in the rapid swing stage and then is kept unchanged and finally is reduced in the contact support stage; the speed of the knee joint in the rapid swing stage is not changed greatly, the speed of the contact support stage is increased firstly, then kept unchanged, and finally reduced;
(2) The output force of the hip pitch joint hydraulic cylinder is increased firstly and then is unchanged and finally is reduced in a quick swing stage and a touch support stage along with the change of the walking speed of the four-foot robot; the output of the knee joint hydraulic cylinder is increased at first and then is reduced at the last after almost no change in the quick swing stage, and the output change in the touch support stage is smaller;
(3) The hip pitch joint and knee joint hydraulic cylinders have larger speed and smaller output in the quick swing stage, and the joint hydraulic cylinders have smaller speed and larger output in the ground contact supporting stage;
(4) The knee joint of the quadruped robot is used as a main output joint in the touchdown supporting stage, and the hip pitch joint is second; thus, the load rule analysis method of the leg joints of the four-foot robot is obtained.
According to the step S3, the matrix determinant from the acting force of the foot end of the supporting leg to the virtual force is 0, so that the lateral forces of the two supporting legs are equal, and the virtual force of the four-foot robot body is decomposed.
In the diagonal gait walking process of the four-foot robot, the foot end track adopts an improved cycloid track, the control method of the swing leg is similar to the machine body control method, a virtual spring damping element is added between the actual position of the foot end and the expected position, the foot end of the swing leg tracks the ideal track, and then ADAMS and MATLAB/Simulink combined simulation is used for realizing the diagonal gait walking control simulation of the robot, so that the change of machine body parameters in the diagonal gait advancing process of the four-foot robot is obtained.
The spring inverted pendulum control algorithm mainly comprises the following steps: the change of the leg placing position is realized by changing the grounding angle when the legs touch the ground; the body posture balance is realized by adjusting the moment of the hip joint during landing; the control of the body bouncing height is realized through the control of the main power in the recovery stage.
The leg joint load rule of the four-foot robot mainly comprises a motion rule and a stress rule of joints.
It is noted that relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (5)
1. A method for analyzing the load rule of leg joints of a quadruped robot is characterized by comprising the following steps: the analysis was performed as follows:
s1, controlling walking of the four-foot robot by using a spring inverted pendulum and a virtual model control algorithm;
the spring inverted pendulum mainly comprises a machine body and spring legs without mass, wherein the hip joint is arranged at the centroid of the machine body, and the spring legs can rotate around the hip joint;
s2, adding virtual spring damping elements between the ideal positions and the actual positions of the respective degrees of freedom, and pulling the machine body to track the ideal positions by utilizing virtual loads generated by the spring damping elements;
s3, analyzing a walking control algorithm and a load rule of the four-foot robot based on the inverted pendulum of the spring and the virtual model;
after the virtual model is added to the quadruped robot body, the relation among the stress, the position and the speed of the body is as follows:
(2.25)
wherein,and->The gravity center of the organism is in an absolute coordinate system>And->Direction location +.>For the height of the body's center of gravity->For the corresponding gain factor, subscript +.>Representing the expected value of the variable, +.>For pitch angle, < >>For yaw angle, after virtual force applied to the machine body is obtained, the virtual force is distributed to foot ends of supporting legs to obtain driving joint moment of the supporting legs, and here, inertial force and coriolis force effects of the four-foot robot are ignored, and only stress of the four-foot robot in static balance is considered, so that the whole stress can be known:
(2.26)
wherein the method comprises the steps of，、/>、/>For the coordinates of the leg and foot ends in the machine body coordinate system, the edge of the leg and foot ends of each support leg is +.>Force in direction +.>Edge->Force in direction +.>Edge->Force in direction +.>Wherein->，/>For the body is->The virtual force in the direction is in the form of a force,for the body is->Virtual force of direction, ++>For the body is->Virtual force of direction, ++>The self weight of the four-foot robot is adopted, then the Jacobian matrix is combined to obtain the driving joint moment of the supporting leg, and meanwhile, a spring inverted pendulum control algorithm is adopted to realize lateral speed control;
the process of accelerating, uniform speed and decelerating the quadruped robot from rest to rest again is called a full-motion process, the weight of the quadruped robot is equivalent to the increase of the body mass, and for convenience of research, the half load of the quadruped robot is defined as 2 times of the body mass, and the full load is defined as 3 times of the body mass;
the leg joints of the four-foot robot adopt a driving mode of a hydraulic driving unit, so that the movement and the stress of a piston rod of the hydraulic cylinder in the walking process of the four-foot robot are required to be obtained through conversion according to the structural parameters of the hydraulic cylinder at the joints;
let the elongation of the hydraulic cylinder beThe relation between the moment and angular velocity of each joint and the output and velocity of the piston rod of the hydraulic cylinder is as follows:
hip side swing joint:
(2.27)
(2.28)
hip pitch joint:
(2.29)
(2.30)
knee joint:
(2.31)
(2.32)
the moment of each driving joint of the four-legged robot is guided into formulas (2.27), (2.28), (2.29), (2.30), (2.31) and (2.32), so that the output force of a piston rod of a hydraulic cylinder in a hydraulic driving unit can be obtained, the load of the leg joint of the four-legged robot is periodically changed, the same period can be divided into two stages, the first stage is smaller in load and smaller in change amplitude, at the moment, the legs are vacated, and the legs are moved forward in a stepping mode, which can be called a quick swing stage; the second stage is a stage with larger load and larger variation amplitude, and the legs are grounded at the moment to realize support, and the stage is called a ground contact support stage, and the legs are emptied and are stressed very little in a rapid swing stage of the legs; in the leg contact supporting stage, the legs contact the ground to support the machine body, at the moment, the legs move very little, but the force of the actuator is relatively large, the angular velocity of each joint is guided into (2.27), (2.29) and (2.31) to obtain the whole length of the hydraulic cylinder in the movement process of each joint of the robot, the displacement of each joint hydraulic cylinder can be obtained by making difference between the whole length and the corresponding initial length, and then the displacement is subjected to time differentiation to obtain the velocity of each hydraulic cylinder;
in the simulation process, the speed of the four-foot robot is firstly increased and then is reduced at a constant speed, the speed and the output of the joint hydraulic cylinder can be obtained, and the walking speed of the four-foot robot is changed; thus, the load rule analysis of the leg joints of the four-foot robot is obtained.
2. The method for analyzing the leg joint load law of the quadruped robot according to claim 1, wherein the method comprises the following steps of: according to the step S3, the matrix determinant from the acting force of the foot end of the supporting leg to the virtual force is 0, so that the lateral forces of the two supporting legs are equal to realize the decomposition of the virtual force of the robot body of the four-foot robot.
3. The method for analyzing the leg joint load law of the quadruped robot according to claim 1, wherein the method comprises the following steps of: in the diagonal gait walking process of the four-foot robot, the foot end track adopts an improved cycloid track, the control method of the swing leg is similar to the machine body control method, a virtual spring damping element is added between the actual position of the foot end and the expected position, the foot end of the swing leg tracks the ideal track, and then ADAMS and MATLAB/Simulink combined simulation is used for realizing the diagonal gait walking control simulation of the robot, so that the change of machine body parameters in the diagonal gait advancing process of the four-foot robot is obtained.
4. The method for analyzing the leg joint load law of the quadruped robot according to claim 1, wherein the method comprises the following steps of: the spring inverted pendulum control algorithm mainly comprises the following steps: the change of the leg placing position is realized by changing the grounding angle when the legs touch the ground; the body posture balance is realized by adjusting the moment of the hip joint during landing; the control of the body bouncing height is realized through the control of the main power in the recovery stage.
5. The method for analyzing the leg joint load law of the quadruped robot according to claim 1, wherein the method comprises the following steps of: the leg joint load rule of the four-foot robot mainly comprises two parts, namely a movement rule and a stress rule of the joints.
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| CN112631277B (en) * | 2020-12-08 | 2022-01-18 | 中山大学 | Balance control method and system for four-legged robot standing posture conversion |
| CN112748741B (en) * | 2020-12-25 | 2022-03-29 | 华南理工大学 | Joint torque determination method for four-footed wall-climbing robot with different postures |
| CN113721649B (en) * | 2021-09-03 | 2023-06-02 | 中国北方车辆研究所 | Multi-support leg force distribution method for four-foot robot based on virtual legs |
| CN114393579B (en) * | 2022-01-04 | 2023-09-22 | 南京航空航天大学 | Robot control method and device based on self-adaptive fuzzy virtual model |
| CN114734445B (en) * | 2022-05-09 | 2024-06-28 | 中兵智能创新研究院有限公司 | Control method for dynamically adapting to load of four-foot robot |
| CN115195900B (en) * | 2022-06-22 | 2023-07-25 | 中国农业大学 | Omnidirectional leveling pose control method for biomimetic mechanical wheel-leg type unmanned chassis in hilly and mountain areas |
| CN115407790B (en) * | 2022-08-16 | 2024-04-26 | 中国北方车辆研究所 | Four-foot robot lateral speed estimation method based on deep learning |
| CN115416017B (en) * | 2022-08-17 | 2024-09-27 | 燕山大学 | Method for constructing electrohydraulic control sense simulation platform of hydraulic quadruped robot |
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