Quadruped robot supporting leg reaction force planning control method and system

Abstract

The invention discloses a quadruped robot supporting leg counter-acting force planning control method, which belongs to the technical field of robot control, and comprises the following steps: firstly, acquiring current gait information of a quadruped robot, and identifying a current supporting leg; secondly, constructing a ground support polygon model; then setting stable support constraint conditions based on a ground support polygon model, and calculating a current expected state of the mass center of the robot; constructing a virtual model of the quadruped robot, and calculating the reactive force of the current supporting legs of the quadruped robot; and finally, the output torque of each motion joint of the quadruped robot is calculated to generate a robot planning control instruction. A stable supporting constraint condition is formed by recognizing supporting legs of the quadruped robot and establishing a ground supporting polygon model, and the current reactive force of the supporting legs is calculated based on the stable supporting constraint condition, so that a robot planning control instruction is generated, planning control over the reactive force is achieved, and the gait stability of the robot is improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of robot control, and particularly relates to a four-legged robot supporting leg reaction force planning control method and system. BACKGROUND

[0002] The legged robot has unique charm in the robot field due to its excellent motion ability and strong environmental adaptability. The four-legged robot has higher passability than the wheeled robot and has a better processing strategy when coping with complex terrain, which makes it have broad application prospects in many fields.

[0003] Taking a common industrial robot as an example, its running environment is usually known and fixed, and part of the industrial robot even needs to deploy the working environment in advance, such as laying tracks, installing a UWB system, and drawing a navigation line. However, in some complex and dangerous and harsh environments, such as unknown terrain exploration, rescue and disaster relief, the advantages of the legged robot are highlighted. It can replace humans to complete the corresponding tasks by virtue of its natural environmental adaptability, effectively reducing the risk faced by personnel.

[0004] However, due to the nonlinearity, instability, and strong interaction with the ground of the control of the four-legged robot, the control is difficult, especially the control of the stability of the body of the four-legged robot is the most important, and in the movement process of the four-legged robot, the crawling gait (three legs supporting at the same time) has the problems of low step frequency and large center of mass fluctuation, which is easy to fall due to the imbalance of the center of gravity.

[0005] As described above, how to provide a four-legged robot supporting leg reaction force planning control method and system capable of improving the gait stability of the four-legged robot has become a problem to be solved. SUMMARY

[0006] The purpose of the present application is to provide a four-legged robot supporting leg reaction force planning control method and system to solve the above problems existing in the prior art.

[0007] In order to achieve the above purpose, the technical scheme adopted by the present application is as follows:

[0008] In a first aspect, the present application provides a four-legged robot supporting leg reaction force planning control method, which comprises the following steps:

[0009] Obtaining the current gait information of the four-legged robot, and identifying the current supporting leg and the current supporting leg foot end position of the four-legged robot based on the current gait information of the four-legged robot;

[0010] Constructing a ground support polygonal model using the current supporting leg foot end position as a corner point, wherein the ground support polygonal model is used to represent the geometric relationship between the current supporting leg foot end position and the projection of the quadruped robot mass point on the ground;

[0011] Based on the ground support polygonal model, a stable support constraint condition is set, and according to the stable support constraint condition, a prediction result of the robot center of mass motion planning trajectory is obtained, so as to calculate the current desired state of the robot center of mass through the prediction result of the robot center of mass motion planning trajectory, wherein the stable support constraint condition is used to constrain the ground support polygonal model to ensure that the quadruped robot is in a stable support state;

[0012] Constructing a virtual model of the quadruped robot, and calculating the current support leg reaction force of the quadruped robot based on the virtual model of the quadruped robot and the current robot center of mass expected state;

[0013] The motion control parameters of the quadruped robot are obtained, and based on the current support leg reaction force and the motion control parameters of the quadruped robot, the output torque of each motion joint of the quadruped robot is calculated to generate a robot planning control instruction according to the output torque of each motion joint of the quadruped robot.

[0014] In one possible design, current gait information of the quadruped robot is obtained, and based on the current gait information of the quadruped robot, the current supporting leg and the current supporting leg foot end position of the quadruped robot are identified, including:

[0015] Obtaining a preset gait cycle and a preset gait rule, wherein the preset gait cycle is used to characterize the time required for each moving joint of the quadruped robot to complete at least one movement and reset, and the preset gait rule is used to characterize the contact conditions between each foot end of the quadruped robot and the ground during normal movement;

[0016] Obtaining a timestamp of the current moment, and calculating a normalized position of the current moment within the gait cycle according to the preset gait cycle using the timestamp of the current moment, so as to obtain a current phase of the quadruped robot at the current moment;

[0017] According to the preset gait rule, determining gait information of the quadruped robot when it is in the current phase as current gait information, wherein the current gait information includes a motion state of each motion joint of the quadruped robot at the current moment and a contact state between each foot of the quadruped robot and the ground at the current moment;

[0018] Identifying the current gait information to obtain the foot of the quadruped robot that is in contact with the ground at the current moment, and marking the corresponding robot leg as the current supporting leg;

[0019] For the foot of the quadruped robot in contact with the ground at the current time, the three-dimensional coordinates of the center point of the contact position of the foot end and the ground are calculated as the current support leg foot end position.

[0020] In a possible design, a ground support polygon model is constructed with the current support leg foot end position as a corner point, including:

[0021] The current support leg foot end position is arranged in ascending order of the horizontal coordinates as a point set;

[0022] According to the order of each point in the point set, each point is sequentially connected by a straight line to form the ground support polygon model, wherein each corner point of the ground support polygon model is the current support leg foot end position.

[0023] In a possible design, before obtaining the stable support constraint condition, further comprising:

[0024] Based on the ground support polygon model, a ground plane equation is established;

[0025] The ground normal vector is calculated through the ground plane equation, and the ground normal vector is unitized to form a unit ground normal vector;

[0026] According to the ground plane equation and the unit ground normal vector, a ground slope compensation value is generated.

[0027] In a possible design, based on the ground support polygon model, a stable support constraint condition is set, and according to the stable support constraint condition, a robot center of mass motion planning trajectory prediction result is obtained, so that the current robot center of mass expected state is calculated through the robot center of mass motion planning trajectory prediction result, including:

[0028] According to the ground support polygon model and the ground slope compensation value, a stable support constraint condition is set;

[0029] According to the current gait information of the quadruped robot, the current time center of mass expected state is defined for the quadruped robot at the current time, wherein the current time center of mass expected state is used to represent the center of mass expected state in the current period;

[0030] A preset gait period and a preset gait rule are obtained, and based on the current time center of mass expected state, the preset gait period and the preset gait rule are recursively obtained to obtain the center of mass expected state in the future multiple periods, and the center of mass expected states in the future multiple periods are integrated to form a center of mass motion expected trajectory;

[0031] According to the stable support constraint condition, the center-of-mass motion expected trajectory is optimized to obtain an optimization result as a robot center-of-mass motion planning trajectory prediction result, wherein the optimization result is an optimal center-of-mass motion expected trajectory conforming to the stable support constraint condition;

[0032] From the robot center-of-mass motion planning trajectory prediction result, a center-of-mass expected state corresponding to a first period of the optimal center-of-mass motion expected trajectory is selected as a current robot center-of-mass expected state.

[0033] In a possible design, a quadruped robot virtual model is constructed, and a current support leg reaction force of the quadruped robot is calculated according to the quadruped robot virtual model and the current robot center-of-mass expected state, including:

[0034] For the quadruped robot, motion variables of each motion joint of the quadruped robot are ignored, so that the quadruped robot is simplified as a single rigid body structure, and parameter information of the quadruped robot is acquired to construct the quadruped robot virtual model;

[0035] Based on the quadruped robot virtual model, a mapping relationship between the robot center-of-mass expected state and a quadruped robot foot force is established;

[0036] The mapping relationship between the robot center-of-mass expected state and the quadruped robot foot force is used to calculate a current quadruped robot foot force corresponding to the current robot center-of-mass expected state;

[0037] According to the current support leg of the quadruped robot and the current quadruped robot foot force, a current support leg reaction force of the quadruped robot is calculated.

[0038] In a possible design, a quadruped robot motion control parameter is acquired, and based on the current support leg reaction force and the quadruped robot motion control parameter, an output torque of each motion joint of the quadruped robot is calculated to generate a robot planning control instruction according to the output torque of each motion joint of the quadruped robot, including:

[0039] The quadruped robot motion control parameter is acquired, wherein the quadruped robot motion control parameter includes a motion control parameter of each motion joint of the quadruped robot and a motion control parameter of a center-of-mass of the quadruped robot;

[0040] Based on the quadruped robot motion control parameter, a dynamics equation of each motion joint of the quadruped robot and the center-of-mass of the quadruped robot is constructed;

[0041] A quadruped robot motion target is acquired to form a planning control priority of each motion joint of the quadruped robot and the center-of-mass of the quadruped robot according to the quadruped robot motion target;

[0042] The output torque of each movement joint of the quadruped robot and the output torque of the center of mass of the quadruped robot are calculated based on the dynamics equation of each movement joint of the quadruped robot and the center of mass of the quadruped robot and the reaction force of the current support leg.

[0043] According to the output torque of each movement joint of the quadruped robot and the output torque of the center of mass of the quadruped robot, a single-joint planning control instruction is generated for each movement joint of the quadruped robot, and a center-of-mass planning control instruction is generated for the center of mass of the quadruped robot.

[0044] According to the planning control priority, the single-joint planning control instructions and the center-of-mass planning control instruction are integrated to form a robot planning control instruction.

[0045] In a second aspect, the present application provides a quadruped robot support leg reaction force planning control system, which comprises:

[0046] A support leg identification unit is configured to obtain current gait information of the quadruped robot, and identify the current support leg and the current support leg foot end position of the quadruped robot based on the current gait information of the quadruped robot.

[0047] A support model establishment unit is configured to construct a ground support polygon model with the current support leg foot end position as a corner point, wherein the ground support polygon model is used to represent the geometric relationship between the current support leg foot end position and the projection of the quadruped robot mass point on the ground.

[0048] A center-of-mass state calculation unit is configured to set a stable support constraint condition based on the ground support polygon model, and obtain a robot center-of-mass motion planning trajectory prediction result according to the stable support constraint condition, so as to calculate a current robot center-of-mass desired state through the robot center-of-mass motion planning trajectory prediction result, wherein the stable support constraint condition is used to constrain the ground support polygon model to ensure that the quadruped robot is in a stable support state.

[0049] A reaction force calculation unit is configured to construct a virtual model of the quadruped robot, and calculate the current support leg reaction force of the quadruped robot by using the current robot center-of-mass desired state according to the virtual model of the quadruped robot.

[0050] An instruction generation unit is configured to obtain movement control parameters of the quadruped robot, and calculate the output torque of each movement joint of the quadruped robot based on the current support leg reaction force and the movement control parameters of the quadruped robot, so as to generate a robot planning control instruction according to the output torque of each movement joint of the quadruped robot.

[0051] In a third aspect, the present application provides an electronic device comprising a memory, a processor and a transceiver connected in sequence for communication, wherein the memory is configured to store a computer program, the transceiver is configured to transmit and receive messages, and the processor is configured to read the computer program and execute the quadruped robot support leg reaction force planning control method according to the first aspect or any possible design of the first aspect.

[0052] In a fourth aspect, the present application provides a computer readable storage medium having instructions stored thereon, wherein the instructions, when executed on a computer, perform the quadruped robot support leg reaction force planning control method according to the first aspect or any possible design of the first aspect.

[0053] In a fifth aspect, the present application provides a computer program product comprising instructions, wherein the instructions, when executed on a computer, cause the computer to perform the quadruped robot support leg reaction force planning control method according to the first aspect or any possible design of the first aspect.

[0054] Beneficial effects: The present application provides a quadruped robot support leg reaction force planning control method, which comprises the following steps: first, obtaining the current gait information of the quadruped robot, and identifying the current support leg and the current support leg foot end position of the quadruped robot based on the current gait information of the quadruped robot; second, constructing a ground support polygon model with the current support leg foot end position as a corner point, wherein the ground support polygon model is used to represent the geometric relationship between the current support leg foot end position and the projection of the quadruped robot mass point on the ground; third, setting a stable support constraint condition based on the ground support polygon model, and obtaining a robot mass center motion planning trajectory prediction result according to the stable support constraint condition, so as to calculate a current robot mass center desired state through the robot mass center motion planning trajectory prediction result, wherein the stable support constraint condition is used to constrain the ground support polygon model to ensure that the quadruped robot is in a stable support state; fourth, constructing a virtual model of the quadruped robot, and calculating the current support leg reaction force of the quadruped robot using the current robot mass center desired state according to the virtual model of the quadruped robot; and fifth, obtaining motion control parameters of the quadruped robot, and calculating the output torque of each motion joint of the quadruped robot based on the current support leg reaction force and the motion control parameters of the quadruped robot, so as to generate a robot planning control instruction according to the output torque of each motion joint of the quadruped robot. Through the identification of the support leg of the quadruped robot and the establishment of the ground support polygon model, a stable support constraint condition is formed, and the current support leg reaction force of the quadruped robot is calculated through the stable support constraint condition to generate a robot planning control instruction, thereby realizing the reaction force planning control of the quadruped robot and significantly improving the gait stability of the quadruped robot in action. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 A schematic flow chart of a method for planning and controlling the reaction force of a quadruped robot's supporting legs according to an embodiment of the present invention;

[0056] Figure 2 A schematic diagram of the functional structure of a quadruped robot support leg reaction force planning and control system provided by an embodiment of the present invention;

[0057] Figure 3 A schematic structural diagram of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0058] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the present invention will be briefly introduced below in conjunction with the drawings and the description of the embodiments or the prior art. Obviously, the following description of the structure of the drawings is only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention.

[0059] It should be understood that although the terms "first," "second," etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element can be referred to as a second element, and similarly, a second element can be referred to as a first element without departing from the scope of the exemplary embodiments of the present invention.

[0060] It should be understood that the term "and / or" that may appear in this document is merely a description of the association relationship between associated objects, indicating that three relationships may exist. For example, A and / or B may indicate three situations: A exists alone, B exists alone, and A and B exist at the same time. The term " / and" that may appear in this document describes another type of association object relationship, indicating that two relationships may exist. For example, A / and B may indicate two situations: A exists alone, and A and B exist alone. In addition, the character " / " that may appear in this document generally indicates that the previous and subsequent associated objects are in an "or" relationship.

[0061] Example:

[0062] like Figure 1 As shown, a first aspect of this embodiment provides a method for planning and controlling the reaction force of a supporting leg of a quadruped robot, which may include but is not limited to the following steps:

[0063] S1. Obtain current gait information of the quadruped robot, and identify a current support leg and a current support leg foot end position of the quadruped robot based on the current gait information of the quadruped robot;

[0064] In a possible implementation, in step S1, the current gait information of the quadruped robot is obtained, and the current support leg and the current support leg foot end position of the quadruped robot are identified based on the current gait information of the quadruped robot, which can but is not limited to be decomposed into steps S11-S15, comprising:

[0065] S11. Obtain a preset gait period and a preset gait rule, wherein the preset gait period is used to represent a time required for each movement joint of the quadruped robot to complete at least one movement and reset, and the preset gait rule is used to represent a contact condition of each foot end of the quadruped robot with the ground in a normal movement process;

[0066] S12. Obtain a timestamp of a current time, and calculate a normalized position of the current time in the gait period by the timestamp of the current time to obtain a current phase of the quadruped robot at the current time according to the preset gait period;

[0067] S13. Determine gait information of the quadruped robot at the current phase as current gait information according to the preset gait rule, wherein the current gait information comprises a movement state of each movement joint of the quadruped robot at the current time and a contact state of each foot of the quadruped robot with the ground at the current time;

[0068] S14. Identify the current gait information to obtain a foot of the quadruped robot in contact with the ground at the current time, and mark a corresponding robot leg of the foot as a current support leg;

[0069] S15. For the foot of the quadruped robot in contact with the ground at the current time, calculate a three-dimensional coordinate of a center point of a contact position of the foot end with the ground as a current support leg foot end position.

[0070] It should be noted that the preset gait rule is a preset condition for ensuring the quadruped robot to normally perform gait, for example, at any gait in the preset gait period, the quadruped robot always has not less than two foot ends in contact with the ground, and among the foot ends in contact with the ground, at least two feet are in a diagonal form. The robot leg corresponding to the foot of the quadruped robot in contact with the ground is a support leg, and the robot leg corresponding to the foot not in contact with the ground is a swing leg.

[0071] The three-dimensional coordinate of the center point of the contact position of the foot end with the ground refers to a coordinate of the center point of the contact position of the foot end with the ground in a world coordinate system, and a specific coordinate value thereof can be obtained through coordinate transformation by a robot coordinate system determined by a center of mass of the quadruped robot.

[0072] S2. Construct a ground support polygon model with the current support leg foot end positions as the vertices, wherein the ground support polygon model is used to represent the geometric relationship between the current support leg foot end positions and the projection of the four-legged robot mass point on the ground;

[0073] In a possible implementation, the step S2 of constructing a ground support polygon model with the current support leg foot end positions as the vertices can but not limited to be decomposed into the following steps S21-S22, comprising:

[0074] S21. Arrange the current support leg foot end positions into a point set in ascending order of the lateral coordinates;

[0075] S22. Connect each point in the point set with a straight line in the order of the points to form the ground support polygon model, wherein each vertex of the ground support polygon model is the current support leg foot end position.

[0076] It should be noted that the ground support polygon model is a closed triangle (three support legs and one swing leg) under most gaits.

[0077] S3. Based on the ground support polygon model, set a stable support constraint condition, and obtain a robot mass center motion planning trajectory prediction result according to the stable support constraint condition, so as to calculate a current robot mass center expected state through the robot mass center motion planning trajectory prediction result, wherein the stable support constraint condition is used to constrain the ground support polygon model to ensure that the four-legged robot is in a stable support state.

[0078] In a possible implementation, before the step S3 of obtaining the stable support constraint condition, the following steps S301-S303 can but not limited to be included:

[0079] S301. Establish a ground plane equation based on the ground support polygon model;

[0080] S302. Calculate a ground normal vector through the ground plane equation, and unitize the ground normal vector to form a unit ground normal vector;

[0081] S303. Generate a ground slope compensation value according to the ground plane equation and the unit ground normal vector.

[0082] It should be noted that the ground plane equation can be established based on the ground support polygon model, for example:

[0083] First, obtain the coordinates of each current support leg foot end position in the world coordinate system:

[0084] P i =[x i ,y i ,z i ] T (i=1,2,3) (1)

[0085] wherein P i is the coordinate of each current support leg foot end position, x i , y i and z i are the x-axis coordinate, y-axis coordinate and z-axis coordinate of each current support leg foot end position respectively, T is the transpose symbol, and i is the guide serial number of each current support leg;

[0086] A foot bottom height vector and a plane parameter matrix are established through the coordinate of each current support leg foot end position:

[0087]

[0088] wherein Z f is the foot bottom height vector, z1, z2 and z3 are the z-axis coordinate of each current support leg foot end position respectively, W ground is the plane parameter matrix, x1, x2 and x3 are the x-axis coordinate of each current support leg foot end position respectively, and y1, y2 and y3 are the y-axis coordinate of each current support leg foot end position respectively;

[0089] The plane parameters (a, b, c) can be calculated by the foot bottom height vector and the plane parameter matrix through the least square method, and the ground plane equation is established:

[0090] z=a+bx+cy (4)

[0091] wherein a, b and c are the plane parameters, z is the height of the ground plane in the world coordinate system, x is the x-axis coordinate of the ground plane in the world coordinate system, and y is the y-axis coordinate of the ground plane in the world coordinate system;

[0092] The ground normal vector n is extracted from the ground plane equation, and is unitized to form the unit ground normal vector n e :

[0093] n=[-b,-c,1] T (5)

[0094]

[0095] wherein n x is the x-axis component of the normal vector in the world coordinate system, n y is the y-axis component of the normal vector in the world coordinate system, and n za z-axis component of the normal vector in the world coordinate system;

[0096] using a unit ground normal vector n e， The roll angle φ and the pitch angle θ can be calculated as:

[0097] φ = arcsin(n y ) (7)

[0098] θ = arctan2(-n x , n z ) (8)

[0099] By fitting the ground plane equation in real time, the roll angle φ and the pitch angle θ are generated, and the roll angle φ and the pitch angle θ are taken as real-time ground slope compensation values. The real-time ground slope compensation values can help form the stable support constraint condition in step S3 to help the quadruped robot correct the footfall height and avoid gait abnormalities when the quadruped robot walks on a slope. In addition, when dealing with complex road conditions, the real-time ground slope compensation can effectively improve the body posture anti-interference ability of the quadruped robot and ensure the gait stability of the quadruped robot.

[0100] In one possible implementation, in step S3, based on the ground support polygon model, a stable support constraint condition is set, and a robot center of mass motion planning trajectory prediction result is obtained according to the stable support constraint condition, so that the current robot center of mass expected state can be calculated through the robot center of mass motion planning trajectory prediction result. This can be, but is not limited to, decomposed into steps S31-S35 as follows, including:

[0101] S31. According to the ground support polygon model and the ground slope compensation value, a stable support constraint condition is set;

[0102] S32. According to the current gait information of the quadruped robot, a current time center of mass expected state is defined for the quadruped robot at the current time, wherein the current time center of mass expected state is used to represent the center of mass expected state in the current period;

[0103] S33. A preset gait period and a preset gait rule are obtained, and based on the current time center of mass expected state, the preset gait period and the preset gait rule are used to recursively obtain the center of mass expected state in future periods, and the center of mass expected states in the future periods are integrated to form a center of mass motion expected trajectory;

[0104] S34. According to the stable support constraint condition, the center of mass motion expected trajectory is optimized, and the optimization result is taken as a robot center of mass motion planning trajectory prediction result, wherein the optimization result is an optimal center of mass motion expected trajectory that meets the stable support constraint condition;

[0105] S35. From the robot centroid motion planning trajectory prediction result, a centroid expected state corresponding to a first period of the optimal centroid motion expected trajectory is selected as a current robot centroid expected state.

[0106] It should be noted that the stable support constraint condition is generated according to the ground support polygon model and the ground slope compensation value, and is used to constrain the ground support polygon model to ensure that the quadruped robot is in a stable support state. Specifically, the generation of the stable support constraint condition needs to introduce a preset stable margin threshold. When the projection of the centroid of the quadruped robot on the ground falls within the ground support polygon model, and the actual stable margin does not exceed the preset stable margin threshold, it can be considered that the quadruped robot at this moment does not have the possibility of falling. The stable margin here is the shortest distance from the projection point of the centroid of the quadruped robot on the ground to each edge of the ground support polygon model. Through the stable support constraint condition, the centroid motion expected trajectory can be optimized to ensure that the finally generated current robot centroid expected state can enable the quadruped robot to maintain a stable gait to move.

[0107] S4. A virtual model of the quadruped robot is constructed, and a current support leg reaction force of the quadruped robot is calculated using the current robot centroid expected state according to the virtual model of the quadruped robot;

[0108] In a possible implementation, in step S4, constructing a virtual model of the quadruped robot and calculating a current support leg reaction force of the quadruped robot using the current robot centroid expected state according to the virtual model of the quadruped robot can be, but is not limited to, decomposed into steps S41-S44, including:

[0109] S41. For the quadruped robot, the motion variables of each motion joint of the quadruped robot are ignored, so that the quadruped robot is simplified as a single rigid body structure, and parameter information of the quadruped robot is obtained to construct a virtual model of the quadruped robot;

[0110] S42. A mapping relationship between the robot centroid expected state and the quadruped robot foot force is established based on the virtual model of the quadruped robot;

[0111] S43. The current quadruped robot foot force corresponding to the current robot centroid expected state is calculated using the mapping relationship between the robot centroid expected state and the quadruped robot foot force;

[0112] S44. The current support leg reaction force of the quadruped robot is calculated according to the current support leg of the quadruped robot and the current quadruped robot foot force.

[0113] S5. Obtain the motion control parameters of the quadruped robot, and based on the current support leg reaction force and the quadruped robot motion control parameters, calculate the output torque of each motion joint of the quadruped robot, so as to generate robot planning control instructions according to the output torque of each motion joint of the quadruped robot.

[0114] In one possible implementation, in step S5, the quadruped robot motion control parameters are obtained, and based on the current support leg reaction force and the quadruped robot motion control parameters, the output torque of each motion joint of the quadruped robot is calculated to generate a robot planning control instruction according to the output torque of each motion joint of the quadruped robot. This can be decomposed into, but is not limited to, the following steps S51-S56, including:

[0115] S51 obtains the quadruped robot motion control parameters, wherein the quadruped robot motion control parameters include the motion control parameters of each motion joint of the quadruped robot and the motion control parameters of the quadruped robot center of mass;

[0116] S52. Based on the motion control parameters of the quadruped robot, the dynamic equations of each motion joint of the quadruped robot and the center of mass of the quadruped robot are constructed;

[0117] S53 obtains the quadruped robot motion target, to form a planning control priority for each motion joint of the quadruped robot and the center of mass of the quadruped robot according to the quadruped robot motion target;

[0118] S54. Based on the dynamic equations of each kinematic joint of the quadruped robot and the center of mass of the quadruped robot, the output torque of each kinematic joint of the quadruped robot and the output torque of the center of mass of the quadruped robot are calculated by the reaction force of the current supporting leg;

[0119] S55. Based on the output torque of each joint of the quadruped robot and the output torque of the center of mass of the quadruped robot, a single joint planning control instruction is generated for each joint of the quadruped robot, and a center of mass planning control instruction is generated for the center of mass of the quadruped robot;

[0120] S56. Integrate the single-joint planning control instructions and the center of mass planning control instructions according to the planning control priority to form a robot planning control instruction.

[0121] It should be noted that the dynamic equations of each moving joint of the quadruped robot and the center of mass of the quadruped robot can be constructed through conventional dynamic technical means and will not be repeated here.

[0122] like Figure 2 As shown, the second aspect of this embodiment provides a hardware system for implementing the quadruped robot supporting leg reaction force planning and control method described in the first aspect of the embodiment, including:

[0123] A supporting leg identification unit is used to obtain the current gait information of the quadruped robot and identify the current supporting leg and the current supporting leg foot end position of the quadruped robot based on the current gait information of the quadruped robot;

[0124] a support model building unit, configured to construct a ground support polygonal model using the current supporting leg foot end position as a corner point, wherein the ground support polygonal model is used to represent the geometric relationship between the current supporting leg foot end position and the projection of the quadruped robot mass point on the ground;

[0125] a center of mass state calculation unit, configured to set a stable support constraint condition based on a ground support polygonal model, and obtain a prediction result of a robot center of mass motion planning trajectory according to the stable support constraint condition, so as to calculate a desired state of the current robot center of mass based on the prediction result of the robot center of mass motion planning trajectory, wherein the stable support constraint condition is used to constrain the ground support polygonal model to ensure that the quadruped robot is in a stable support state;

[0126] a support reaction force calculation unit, configured to construct a virtual model of the quadruped robot and calculate the current support leg reaction force of the quadruped robot based on the virtual model of the quadruped robot and the current robot center of mass expected state;

[0127] The instruction generation unit is used to obtain the motion control parameters of the quadruped robot, and based on the current support leg reaction force and the quadruped robot motion control parameters, calculate the output torque of each motion joint of the quadruped robot, so as to generate robot planning control instructions according to the output torque of each motion joint of the quadruped robot.

[0128] The working process, working details and technical effects of the system provided in this embodiment can be found in the first aspect of the embodiment and will not be described in detail here.

[0129] like Figure 3 As shown, the third aspect of this embodiment provides an electronic device, comprising: a memory, a processor and a transceiver that are communicatively connected in sequence, wherein the memory is used to store computer programs, the transceiver is used to send and receive messages, and the processor is used to read the computer program and execute the quadruped robot support leg reaction force planning and control method as described in the first aspect of the embodiment.

[0130] Specifically, the memory can include, but is not limited to, random access memory (RAM), read only memory (ROM), flash memory, first input first output (FIFO) memory, first in last out (FILO) memory, and the like; specifically, the processor can include one or more processing cores, such as a 4-core processor, an 8-core processor, and the like. The processor can be implemented in at least one of the hardware forms of a DSP (Digital Signal Processing), an FPGA (Field-Programmable Gate Array), and a PLA (Programmable Logic Array), and the processor can also include a main processor and a coprocessor. The main processor is a processor for processing data in an awake state, also known as a CPU (Central Processing Unit); the coprocessor is a low-power processor for processing data in a standby state.

[0131] In some embodiments, the processor can be integrated with a GPU (Graphics Processing Unit) that is responsible for rendering and drawing the content required to be displayed on the display screen. For example, the processor can be, but is not limited to, a microprocessor of the STM32F105 series, a RISC (reduced instruction set computer) microprocessor, an X86 architecture processor, or a processor integrated with an embedded neural network processing unit (NPU). The transceiver can be, but is not limited to, a WIFI wireless transceiver, a Bluetooth wireless transceiver, a GPRS (General Packet Radio Service) wireless transceiver, a ZigBee wireless transceiver, a 3G transceiver, a 4G transceiver, and / or a 5G transceiver, and the like. In addition, the device can also include, but is not limited to, a power module, a display screen, and other necessary components.

[0132] The working process, working details, and technical effects of the electronic device provided in the embodiment can be referred to the first aspect of the embodiment, and will not be repeated here.

[0133] The fourth aspect of the embodiment provides a storage medium storing instructions of the four-legged robot support leg reaction force planning control method in the first aspect of the embodiment, that is, the storage medium stores the instructions, and when the instructions run on a computer, the four-legged robot support leg reaction force planning control method in the first aspect of the embodiment is executed.

[0134] The storage medium refers to a carrier for storing data, which can include, but is not limited to, a floppy disk, an optical disk, a hard disk, a flash memory, a USB flash disk, a memory stick and the like, and the computer can be a general-purpose computer, a special-purpose computer, a computer network or other programmable devices.

[0135] The working process, working details and technical effects of the storage medium provided by the embodiment can be referred to the first aspect of the embodiment, and will not be described here.

[0136] The fifth aspect of the embodiment provides a computer program product containing instructions, which, when running on a computer, causes the computer to execute the four-legged robot support leg reaction force planning control method in the first aspect of the embodiment, wherein the computer can be a general-purpose computer, a special-purpose computer, a computer network or other programmable devices.

[0137] Finally, it should be noted that: the above only describes the preferred embodiments of the present application, and is not used to limit the protection scope of the present application. Any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A quadruped robot support leg reaction force planning and control method, characterized in that: include: Acquire the current gait information of the quadruped robot, and based on the current gait information of the quadruped robot, identify the current supporting leg and the current supporting leg foot end position of the quadruped robot; Constructing a ground support polygonal model using the current supporting leg foot end position as a corner point, wherein the ground support polygonal model is used to represent the geometric relationship between the current supporting leg foot end position and the projection of the quadruped robot mass point on the ground; Based on the ground support polygonal model, a stable support constraint condition is set, and according to the stable support constraint condition, a prediction result of the robot center of mass motion planning trajectory is obtained, so as to calculate the current desired state of the robot center of mass through the prediction result of the robot center of mass motion planning trajectory, wherein the stable support constraint condition is used to constrain the ground support polygonal model to ensure that the quadruped robot is in a stable support state; Constructing a virtual model of the quadruped robot, and calculating the current support leg reaction force of the quadruped robot based on the virtual model of the quadruped robot and the current robot center of mass expected state; The quadruped robot motion control parameters are obtained, and based on the current support leg reaction force and the quadruped robot motion control parameters, the output torque of each motion joint of the quadruped robot is calculated to generate a robot planning control instruction according to the output torque of each motion joint of the quadruped robot.

2. The quadruped robot support leg reaction force planning and control method according to claim 1, characterized in that: Obtain the current gait information of the quadruped robot, and based on the current gait information of the quadruped robot, identify the current supporting leg and the current supporting leg foot end position of the quadruped robot, including: Obtaining a preset gait cycle and a preset gait rule, wherein the preset gait cycle is used to characterize the time required for each moving joint of the quadruped robot to complete at least one movement and reset, and the preset gait rule is used to characterize the contact conditions between each foot end of the quadruped robot and the ground during normal movement; Obtaining a timestamp of the current moment, and calculating a normalized position of the current moment within the gait cycle according to the preset gait cycle using the timestamp of the current moment, so as to obtain a current phase of the quadruped robot at the current moment; According to the preset gait rule, determining gait information of the quadruped robot when it is in the current phase as current gait information, wherein the current gait information includes a motion state of each motion joint of the quadruped robot at the current moment and a contact state between each foot of the quadruped robot and the ground at the current moment; Identifying the current gait information to obtain the foot of the quadruped robot that is in contact with the ground at the current moment, and marking the corresponding robot leg as the current supporting leg; For the foot of the quadruped robot that is in contact with the ground at the current moment, the three-dimensional coordinates of the center point of the contact part between the foot end and the ground are calculated as the current position of the foot end of the supporting leg.

3. The quadruped robot support leg reaction force planning and control method according to claim 1, characterized in that: Using the current supporting leg foot end position as the corner point, a ground support polygonal model is constructed, including: Arrange the current supporting leg foot end positions into a point set in ascending order of transverse coordinates; In accordance with the order of the points in the point set, the points are connected in sequence with straight lines to form the ground support polygonal model, wherein the corner points of the ground support polygonal model are the positions of the current supporting leg and foot ends.

4. The quadruped robot support leg reaction force planning and control method according to claim 1, characterized in that: Before obtaining the stable support constraint conditions, it also includes: Establishing a ground plane equation based on the ground support polygonal model; Calculating a ground normal vector using the ground plane equation, and normalizing the ground normal vector to form a unit ground normal vector; A ground slope compensation value is generated according to the ground plane equation and the unit ground normal vector.

5. The quadruped robot support leg reaction force planning and control method according to claim 4, characterized in that: Based on the ground support polygon model, a stable support constraint condition is set, and according to the stable support constraint condition, a prediction result of the robot center of mass motion planning trajectory is obtained, so as to calculate the current robot center of mass expected state through the robot center of mass motion planning trajectory prediction result, including: Setting a stable support constraint condition according to the ground support polygonal model and the ground slope compensation value; Defining a center of mass expected state at a current moment for the quadruped robot according to the current gait information of the quadruped robot, wherein the center of mass expected state at the current moment is used to represent the center of mass expected state within a current cycle; Obtaining a preset gait cycle and a preset gait rule, and based on the expected state of the center of mass at the current moment, deducing the expected state of the center of mass for multiple future cycles according to the preset gait cycle and the preset gait rule, integrating the expected state of the center of mass for each future cycle to form an expected trajectory of the center of mass movement; Optimizing the desired trajectory of the center of mass motion according to the stable support constraint condition, and using the optimization result as a prediction result of the robot center of mass motion planning trajectory, wherein the optimization result is the optimal desired trajectory of the center of mass motion that meets the stable support constraint condition; From the prediction results of the robot center of mass motion planning trajectory, the center of mass expected state corresponding to the first period of the optimal center of mass motion expected trajectory is selected as the current robot center of mass expected state.

6. The quadruped robot support leg reaction force planning and control method according to claim 1, characterized in that: Constructing a virtual model of the quadruped robot, and calculating the current support leg reaction force of the quadruped robot based on the virtual model of the quadruped robot and using the current robot center of mass expected state, including: For the quadruped robot, the motion variables of each joint are ignored, so that the quadruped robot is simplified into a single rigid body structure, and the parameter information of the quadruped robot is obtained to construct a virtual model of the quadruped robot; Based on the quadruped robot virtual model, a mapping relationship between the desired state of the robot's center of mass and the plantar force of the quadruped robot is established; Calculate the current quadruped robot plantar force corresponding to the current robot center of mass desired state using a mapping relationship between the robot center of mass desired state and the quadruped robot plantar force; The reaction force of the current supporting leg of the quadruped robot is calculated according to the current supporting leg of the quadruped robot and the current plantar force of the quadruped robot.

7. The quadruped robot support leg reaction force planning and control method according to claim 1, characterized in that: Obtaining the motion control parameters of the quadruped robot, and calculating the output torque of each motion joint of the quadruped robot based on the current support leg reaction force and the quadruped robot motion control parameters, so as to generate a robot planning control instruction according to the output torque of each motion joint of the quadruped robot, including: Acquiring motion control parameters of the quadruped robot, wherein the motion control parameters of the quadruped robot include motion control parameters of each motion joint of the quadruped robot and motion control parameters of the center of mass of the quadruped robot; Based on the motion control parameters of the quadruped robot, dynamic equations of each motion joint of the quadruped robot and the center of mass of the quadruped robot are constructed; Obtaining a motion target of the quadruped robot to form a planning and control priority for each motion joint of the quadruped robot and the center of mass of the quadruped robot according to the motion target of the quadruped robot; Based on the dynamic equations of each motion joint of the quadruped robot and the center of mass of the quadruped robot, the output torque of each motion joint of the quadruped robot and the output torque of the center of mass of the quadruped robot are calculated respectively through the reaction force of the current supporting leg; According to the output torque of each motion joint of the quadruped robot and the output torque of the center of mass of the quadruped robot, a single joint planning control instruction is generated for each motion joint of the quadruped robot, and a center of mass planning control instruction is generated for the center of mass of the quadruped robot; According to the planning control priority, the single joint planning control instructions and the center of mass planning control instructions are integrated to form a robot planning control instruction.

8. A quadruped robot support leg reaction force planning and control system, characterized in that: include: A supporting leg identification unit is used to obtain the current gait information of the quadruped robot and identify the current supporting leg and the current supporting leg foot end position of the quadruped robot based on the current gait information of the quadruped robot; a support model building unit, configured to construct a ground support polygonal model using the current supporting leg foot end position as a corner point, wherein the ground support polygonal model is used to represent the geometric relationship between the current supporting leg foot end position and the projection of the quadruped robot mass point on the ground; a center of mass state calculation unit, configured to set a stable support constraint condition based on a ground support polygonal model, and obtain a prediction result of a robot center of mass motion planning trajectory according to the stable support constraint condition, so as to calculate a desired state of the current robot center of mass based on the prediction result of the robot center of mass motion planning trajectory, wherein the stable support constraint condition is used to constrain the ground support polygonal model to ensure that the quadruped robot is in a stable support state; a support reaction force calculation unit, configured to construct a virtual model of the quadruped robot and calculate the current support leg reaction force of the quadruped robot based on the virtual model of the quadruped robot and the current robot center of mass expected state; The instruction generation unit is used to obtain the motion control parameters of the quadruped robot, and based on the current support leg reaction force and the quadruped robot motion control parameters, calculate the output torque of each motion joint of the quadruped robot, so as to generate robot planning control instructions according to the output torque of each motion joint of the quadruped robot.

9. An electronic device, characterized in that: It includes a memory, a processor and a transceiver that are communicatively connected in sequence, wherein the memory is used to store computer programs, the transceiver is used to send and receive messages, and the processor is used to read the computer program and execute the quadruped robot support leg reaction force planning and control method as described in any one of claims 1 to 7.

10. A computer program product comprising a computer program or instructions, characterized in that When executed by a computer, the computer program or the instruction implements the quadruped robot supporting leg reaction force planning and control method according to any one of claims 1 to 7.

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