Modularized robot dynamics modeling method

Abstract

The embodiment of the invention provides a modular robot dynamics modeling method, which realizes modular robot dynamics modeling, and comprises the following steps: obtaining a modular robot topological structure mathematical representation, a modular unit three-dimensional model, a modular unit three-dimensional model and a modular unit three-dimensional model; basic kinematics parameter information, basic dynamics parameter information, a module unit motion transmission library and a structure equivalent library are obtained, and all motion transmission branch chains of the robot are obtained according to topological structure mathematical representation of the robot; and the connection state of the module units in each motion transmission branch chain and the motion transmission mode between the two module units with the connection relation are analyzed, equivalent structural bodies and kinetic parameters of the module units are obtained, a dynamic modeling method of the modular robot based on distributed parameter obtaining is designed, and a dynamic model of the modular robot is obtained. According to the technical scheme provided by the embodiment of the invention, rapid dynamic modeling of the homogeneous modular robot can be realized.

Description

[Technical field]

[0001] The invention relates to a modular robot dynamics modeling method and belongs to the field of robot dynamics modeling. [Background technology]

[0002] With the further promotion of industrial automation, the application of robots in various fields has gradually become popular. Robots with single performance and fixed structure will be difficult to apply to tasks with diverse loads and requirements. The concept of modular robots was proposed in 1988. Such robots are generally composed of multiple identical modules (homogeneous) or different modules (heterogeneous). By changing the number of modules and their relative positions, the robot can be reconstructed into a new configuration and obtain new functions to adapt to the changing working environment and meet the diverse task requirements. Therefore, research on modular robots can promote the further development of my country's robotics field.

[0003] Compared with heterogeneous modular robots, homogeneous modular robot modules can replace each other, and the modules have strong scalability and versatility. They can carry out design, manufacturing, assembly, maintenance and other related work in batches, and are easy to use. Therefore, the application scenarios of homogeneous modular robots are more extensive. The application of robots needs to be based on dynamic modeling, and the same is true for homogeneous modular robots. Regarding the dynamic modeling of homogeneous modular robots, in traditional modeling methods, the robot dynamic parameters need to be manually obtained based on the three-dimensional model, which is not suitable for modular robots with non-fixed topological structures and dynamically changing. Therefore, conducting research on the dynamic modeling of homogeneous modular robots has important theoretical research value. [Summary of the invention]

[0004] In view of this, the present invention provides a modular robot dynamics modeling method to achieve dynamics modeling of a homogeneous modular robot.

[0005] An embodiment of the present invention provides a modular robot dynamics modeling method, characterized in that the method includes:

[0006] Obtain the mathematical representation of the modular robot topology and the three-dimensional model of the module unit;

[0007] According to the three-dimensional model of the module unit, the module unit body center coordinate system and interface coordinate system are established to obtain the basic kinematic parameter information and basic dynamic parameter information of the module unit;

[0008] According to the three-dimensional model of the module unit and the basic kinematic parameter information of the module unit, a module unit motion transfer library is obtained;

[0009] According to the three-dimensional model of the module unit, the module unit motion transfer library, and the basic dynamic parameter information of the module unit, the module unit structure equivalent library is obtained;

[0010] According to the mathematical representation of the modular robot topological structure, the modular robot grounding module unit number, grounding interface number, and terminal module unit number are obtained;

[0011] According to the mathematical representation of the modular robot topological structure and the modular robot grounding module unit number, grounding interface number, and terminal module unit number, all motion transmission branches of the modular robot are obtained;

[0012] According to all motion transmission branches of the modular robot, the connection state of the module units in each motion transmission branch and the motion transmission mode between two module units with a connection relationship are obtained;

[0013] According to the module unit structure equivalent library, the basic dynamic parameter information of the module unit and the connection state of the module unit in each motion transmission branch chain, the module unit equivalent structure and the dynamic parameters of the equivalent structure are obtained;

[0014] According to the equivalent structure of the module unit, the dynamic parameters of the equivalent structure, and the motion transmission mode between two connected module units, a distributed parameter acquisition strategy for the modular robot is designed to obtain the dynamic parameters corresponding to the motion transmission branch chain;

[0015] According to the equivalent structure of the modular unit, the dynamic parameters of the equivalent structure, the motion transmission method between two connected modular units, the distributed parameter acquisition strategy of the modular robot and all the motion transmission branches of the modular robot, a dynamic modeling method of the modular robot based on distributed parameter acquisition is designed to obtain the dynamic model of the modular robot.

[0016] In the above method, based on the three-dimensional model of the module unit, the module unit body center coordinate system and the interface coordinate system are established to obtain the basic kinematic parameter information and basic dynamic parameter information of the module unit, including:

[0017] According to the three-dimensional model of the module unit, the module unit body center coordinate system and interface coordinate system are established to obtain the basic kinematic parameter information of the module unit;

[0018] According to the three-dimensional model of the module unit, the module unit structure is split to obtain each substructure of the module unit, and the centroid coordinate system of each substructure is established;

[0019] The basic dynamic parameters of the module unit are obtained according to the three-dimensional model of the module unit, each substructure of the module unit, and the centroid coordinate system of each substructure.

[0020] In the above method, based on the three-dimensional model of the module unit, the module unit body center coordinate system and the interface coordinate system are established to obtain the basic kinematic parameter information of the module unit, including:

[0021] The spinor coordinates of each rotation axis in the body-centered coordinate system;

[0022] The relative position relationship matrix between each interface coordinate system and the body center coordinate system;

[0023] The connection orientation relationship matrix existing when two interfaces are connected is used to indicate the specific docking status of the positioning device when the interfaces are docked.

[0024] In the above method, the module unit structure is split according to the module unit three-dimensional model to obtain each substructure of the module unit, and the centroid coordinate system of each substructure is established, including:

[0025] The following rules apply to splitting the module unit structure:

[0026] The parts connected to the rotor of the motor in the interface can be assembled into a substructure, the parts connected to the stator of the motor in the interface can be assembled into a substructure, the parts connected to the rotor of the motor in the body center can be assembled into a substructure, and the parts connected to the stator of the motor in the body center can be assembled into a substructure;

[0027] The method for determining the centroid coordinate system of each substructure of the module unit is:

[0028] The centroid of each substructure is selected as the origin of the centroid coordinate system. The selection of the axis of the centroid coordinate system of each substructure follows the following rules:

[0029] For the substructure assembled from the components that are fixedly connected to the rotor of the motor in the interface, the axial direction of its centroid coordinate system is consistent with the interface coordinate system;

[0030] For the substructure assembled from the components fixedly connected to the stator of the motor in the interface, the axial direction of the centroid coordinate system is consistent with the body-centroid coordinate system;

[0031] For the substructure assembled from the parts fixedly connected to the rotor of the motor in the body center, the axial direction of its centroid coordinate system is consistent with the body center coordinate system;

[0032] For a substructure assembled from components that are fixedly connected to the stator of the motor in the body center, the axial direction of its centroid coordinate system is consistent with the body center coordinate system.

[0033] In the above method, the basic dynamic parameters of the module unit are obtained according to the three-dimensional model of the module unit, each substructure of the module unit, and the centroid coordinate system of each substructure, including:

[0034] The quality of each substructure;

[0035] The position vector of the center of mass of each substructure relative to the interface coordinate system or the body center coordinate system which is in the same direction as the center of mass coordinate system;

[0036] The inertia tensor of each substructure relative to the center-of-mass coordinate system.

[0037] In the above method, according to the three-dimensional model of the module unit and the basic kinematic parameter information of the module unit, a module unit motion transfer library is obtained, including:

[0038] According to the three-dimensional model of the module unit, the interface arrangement, interface type, mechanical structure size, and degree of freedom arrangement information of the module unit are obtained;

[0039] According to the interface arrangement, interface type, and mechanical structure size information of the module unit, all valid connection states of the module unit are obtained;

[0040] According to the degree of freedom arrangement information of the module unit and the basic kinematic parameter information of the module unit, the rotation axis and kinematic parameters contained in each effective connection state of the module unit are obtained;

[0041] According to all effective connection states of the module unit, the rotation axis and kinematic parameters contained in each effective connection state of the module unit, a module unit motion transfer library is obtained.

[0042] In the above method, all valid connection states of the module unit are obtained according to the interface arrangement, interface type, and mechanical structure size information of the module unit, including:

[0043] According to the interface arrangement and interface type of the module unit, based on the enumeration method, all connection states of the module unit are obtained through permutations and combinations;

[0044] According to the mechanical structure dimension information of the module unit and all the connection states of the module unit, the connection states with structural interference are eliminated to obtain all the valid connection states of the module unit.

[0045] In the above method, according to the three-dimensional model of the module unit, the module unit motion transfer library, and the basic dynamic parameter information of the module unit, the module unit structure equivalent library is obtained, including:

[0046] According to the three-dimensional model of the module unit, the interface arrangement, interface type, mechanical structure size, and degree of freedom arrangement information of the module unit are obtained;

[0047] According to the interface arrangement, interface type, and mechanical structure size information of the module unit, all valid connection states of the module unit are obtained;

[0048] According to all valid connection states of the module unit, a motion input terminal interface and a motion output terminal interface of each valid connection state of the module unit are obtained;

[0049] According to the motion input terminal interface and the motion output terminal interface in each connection state of the module unit and the module unit motion transfer library, the attributes corresponding to each substructure in each effective connection state of the module unit are obtained;

[0050] According to the attributes corresponding to each substructure in each effective connection state of the module unit, the equivalent structure in each effective connection state of the module unit is obtained;

[0051] According to the basic dynamic parameter information of the equivalent structure and the module unit under each effective connection state of the module unit, the dynamic parameters of the equivalent structure under each effective connection state of the module unit are obtained;

[0052] Obtain a module unit structural equivalent library according to all valid connection states of the module unit, the equivalent structure of the module unit under each valid connection state, and the dynamic parameters of the equivalent structure of the module unit under each valid connection state;

[0053] Among them, the motion input interface refers to the interface in the current module unit on the motion transmission branch of the modular robot, which is closest to the ground module unit in the current effective connection state; the motion output interface refers to the interface in the current module unit on the motion transmission branch of the modular robot, which is closest to the terminal module unit in the current effective connection state;

[0054] The attributes corresponding to each substructure in each effective connection state of the module unit are the components that transmit the motion and force of a certain rotation axis, wherein the rotation axis is determined according to the rotation axis included in the current effective connection state in the module unit motion transmission library;

[0055] The final representation of the equivalent structure in each effective connection state of the module unit is a collection of multiple equivalent structures;

[0056] The dynamic parameters of the equivalent structure under each effective connection state of the module unit include the mass of the equivalent structure, the position vector of the center of mass of the equivalent structure relative to the interface coordinate system or the body center coordinate system corresponding to the previous rotation axis, the inertia tensor of the equivalent structure, and the space inertia matrix of the equivalent structure;

[0057] The centroid coordinate system of the equivalent structure is determined as follows:

[0058] The center of mass of the equivalent structure is selected as the origin of the center of mass coordinate system, and the axis of the center of mass coordinate system is consistent with the interface coordinate system or body center coordinate system corresponding to the previous rotation axis;

[0059] The mass of the equivalent structure i for:

[0060]

[0061] Among them, mk is the mass of the modular unit substructure k in the equivalent structure i, a-b Λ i (i=1,2,3,...) is the set of module unit substructures contained in the equivalent structure i when the module unit is in the effective connection state ab, a is the motion input terminal interface of the module unit in the current effective connection state, b is the motion output terminal interface of the module unit in the current effective connection state, and a≠b;

[0062] The center of mass of the equivalent structure i relative to the interface coordinate system or body center coordinate system ΣJ corresponding to the previous rotation axis i The position vector for:

[0063]

[0064] in, is the center of mass of the module unit substructure k in the equivalent structure i in the coordinate system ΣJ i The description below can be calculated by using the basic dynamic parameters of the module unit through coordinate system transformation;

[0065] Establish the centroid coordinate system ΣL of the equivalent structure i i , the inertia tensor of the equivalent structure i is:

[0066]

[0067] in, is the inertia tensor of the module unit substructure k in the equivalent structure i in the coordinate system ΣL i The description below can be calculated by using the basic dynamic parameters of the module unit through coordinate system transformation;

[0068] The spatial inertia matrix of the equivalent structure i is:

[0069]

[0070] Among them, 0 3×3 is a zero matrix of dimension 3×3, I 3×3 is the unit matrix of dimension 3×3.

[0071] In the above method, according to the mathematical representation of the modular robot topological structure, the modular robot grounding module unit number, grounding interface number, and terminal module unit number are obtained, including:

[0072] For n topo_module The modular robot topology structure of modules is mathematically represented as

[0073]

[0074]

[0075] Among them, n topo_module Represents the number of modules contained in the modular robot topology; m i (i=1,2,...,n topo_module ) represents the module numbers in the modular robot topology; matrix B is called the grounding relationship matrix, ba i (i=1,2,...,n topo_module ) indicates whether the module in the modular robot topology is grounded as a base when used, ba i =0 means module m i When not grounded, i ≠0 means module m i When using ba i The interface ground is used as the base; the matrix C is called the connection relationship matrix of the modular robot, c ij (i=1,2,...,n topo_module ; j = 1, 2, ..., n topo_module )∈{1,...,n surf_con} represents the interface number that connects module mi to module mj. When i=j, c ij =0(i=1,2,...,n topo_module ; j = 1, 2, ..., n topo_module ), n surf_con represents the number of surface interfaces of a single module; the matrix O is called the connection orientation relationship matrix of the modular robot, ij (i=1,2,...,n topo_module ; j = 1, 2, ..., n topo_module ) indicates module m i With module m j The connection orientation relationship, when i = j, co ij =0(i=1,2,...,n topo_module ; j = 1, 2, ..., n topo_module );

[0076] According to the mathematical representation of the modular robot topology structure, including matrix M, matrix A, matrix C, and matrix O, the row numbers of the matrix C containing only one non-zero element, the non-zero elements in the matrix A and their positions are obtained;

[0077] According to the matrix A, the non-zero elements in the matrix A and their positions, the non-zero elements in the matrix A are the grounding interface numbers, and the elements corresponding to the positions of the non-zero elements in the matrix M are read to obtain the modular robot grounding module unit number and the grounding interface number;

[0078] According to the row number containing only one non-zero element in the matrix C and the matrix M, the element at the position corresponding to the row number in the matrix M is read to obtain the terminal module unit number of the modular robot.

[0079] In the above method, all motion transmission branches of the modular robot are obtained according to the mathematical representation of the modular robot topological structure and the modular robot grounding module unit number, grounding interface number, and terminal module unit number, including:

[0080] Taking the grounding interface number of the modular robot's grounding module unit number as the starting point and the modular robot's terminal module unit number as the end point, based on the matrix C in the mathematical representation of the modular robot's topological structure, based on depth-first traversal, the modules and their interface information that the modular robot needs to pass through for motion transmission from the starting point to the end point are searched to obtain all the motion transmission branches of the modular robot.

[0081] In the above method, based on all motion transmission branches of the modular robot, the connection state of the module units in each motion transmission branch and the motion transmission mode between two module units having a connection relationship are obtained, including:

[0082] There are two ways of motion transmission between two connected module units:

[0083] The motion output of the previous module unit is an interface including a motor;

[0084] The motion output of the preceding module unit is an interface without a motor.

[0085] In the above method, according to the equivalent structure of the module unit, the dynamic parameters of the equivalent structure, and the motion transmission mode between two module units with a connection relationship, a distributed parameter acquisition strategy of the modular robot is designed to obtain the dynamic parameters corresponding to the motion transmission branch chain, including:

[0086] According to the equivalent structure of the module unit, the dynamic parameters of the equivalent structure, and the motion transmission mode between two module units having a connection relationship, a dynamic parameter processing strategy corresponding to the motion transmission mode between the two module units having a connection relationship is obtained;

[0087] According to the dynamic parameter processing strategy corresponding to the motion transmission mode between two connected module units, a distributed parameter acquisition strategy for modular robots is designed to obtain the dynamic parameters corresponding to the motion transmission branch chain;

[0088] Among them, the dynamic parameter processing strategies corresponding to the motion transmission mode between two module units with a connection relationship include:

[0089] When the motion transmission mode between two connected module units is that the motion output end of the previous module unit is an interface including a motor, the initial equivalent structure of the latter module unit and the final equivalent structure of the previous module unit are recalculated according to the process of obtaining the final equivalent structure of the previous module unit;

[0090] When the motion transmission mode between two connected module units is that the motion output end of the previous module unit is an interface that does not include a motor, the end equivalent structure of the previous module unit is directly merged with the start equivalent structure of the next module unit.

[0091] In the above method, according to the equivalent structure of the module unit, the dynamic parameters of the equivalent structure, the motion transmission mode between two module units with a connection relationship, the distributed parameter acquisition strategy of the modular robot and all the motion transmission branches of the modular robot, a dynamic modeling method of the modular robot based on distributed parameter acquisition is designed to obtain the dynamic model of the modular robot, including:

[0092] A modular robot motion transmission chain consisting of m modular units and n degrees of freedom is subjected to external force rotation. Under the action of

[0093]

[0094] in, is the Jacobian matrix, and Described in the same coordinate system; is the inertia force matrix, as shown below; are the Coriolis force and centrifugal force terms on each joint during the motion of the modular robot, as shown in the following formula; is the gravitational force on the modular robot during its motion, as shown in the following equation; They are the joint angle, joint angular velocity, joint angular acceleration, and driving torque vector on the current motion transmission branch chain;

[0095] One contains The dynamic model of the modular robot with a motion transmission branch chain is:

[0096]

[0097] Among them, q i , τ i They are the joint angle, joint angular velocity, joint angular acceleration, and driving torque vector on the i-th motion transmission branch. is the external force rotation amount received by the end of the i-th motion transmission branch,

[0098] By analyzing the motion transfer branch chain, it can be split into ζ non-bifurcated motion branches, and then the modular robot dynamics model can be further converted into:

[0099]

[0100] in, represents the driving torque provided by the joint of the k-th non-bifurcation motion branch during the motion of the i-th motion branch, It represents the inertial force coupling influence matrix generated by the joint motion of the j-th non-bifurcation motion branch and the joint motion of the k-th non-bifurcation motion branch during the motion of the i-th motion branch. According to the inertial force matrix M of the i-th motion branch i Obtained, represents the influence of the inertial force of the joint acceleration of the j-th non-bifurcation motion branch on the joint motion of the k-th non-bifurcation motion branch, It represents the Coriolis force and centrifugal force coupling influence matrix generated by the joint motion of the j-th non-bifurcation motion branch and the joint motion of the k-th non-bifurcation motion branch during the motion of the i-th motion branch. According to the inertia force matrix C of the i-th motion branch i Obtained, represents the influence of the acceleration of the j-th non-bifurcation motion branch joint on the Coriolis force and centrifugal force of the k-th non-bifurcation motion branch joint motion, represents the gravitational term on the joint motion of the kth non-bifurcation motion branch during the motion of the i-th motion branch, The Jacobian matrix representing the joint motion contained in the k-th branch of non-bifurcation motion relative to the i-th terminal motion;

[0101] Among them, the non-branched motion branch means that during the motion of each joint on the current branch, the transmission of motion or force has only a single direction.

[0102] It can be seen from the above technical solutions that the embodiments of the present invention have the following beneficial effects:

[0103] In the technical solution of the embodiment of the present invention, a mathematical representation of the topological structure of the modular robot and a three-dimensional model of the modular unit are obtained. Based on the three-dimensional model of the modular unit, a body-centered coordinate system and an interface coordinate system of the modular unit are established to obtain basic kinematic parameter information and basic dynamic parameter information of the modular unit. Based on the three-dimensional model of the modular unit and the basic kinematic parameter information of the modular unit, a modular unit motion transfer library is obtained. Based on the three-dimensional model of the modular unit, the modular unit motion transfer library and the basic dynamic parameter information of the modular unit, a modular unit structural equivalent library is obtained. Based on the mathematical representation of the topological structure of the modular robot, the grounding module unit number, the grounding interface number and the terminal module unit number of the modular robot are obtained. Based on the mathematical representation of the topological structure of the modular robot and the grounding module unit number, the grounding interface number and the terminal module unit number of the modular robot, all motion transfer branches of the modular robot are obtained. Based on all the motion transfer branches of the modular robot, the connection state of the modular units in each motion transfer branch and the motion transfer method between two modular units with a connection relationship are obtained. According to the module unit structure equivalent library, the basic dynamic parameter information of the module unit and the connection status of the module unit in each motion transmission branch, the equivalent structure of the module unit and the dynamic parameters of the equivalent structure are obtained. According to the equivalent structure of the module unit, the dynamic parameters of the equivalent structure and the motion transmission mode between two module units with a connection relationship, the distributed parameter acquisition strategy of the modular robot is designed to obtain the dynamic parameters corresponding to the motion transmission branch. According to the equivalent structure of the module unit, the dynamic parameters of the equivalent structure, the motion transmission mode between two module units with a connection relationship, the distributed parameter acquisition strategy of the modular robot and all motion transmission branches of the modular robot, the dynamic modeling method of the modular robot based on distributed parameter acquisition is designed to obtain the dynamic model of the modular robot. Therefore, the dynamic modeling of the modular robot can be realized. Combined with the characteristics of the modular robot, based on the dynamic parameters of the module unit, more efficient dynamic modeling of the homogeneous modular robot is realized, providing a model basis for the application of modular robots.

Brief Description of the Drawings

[0104] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It is obvious that the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creativity and labor.

[0105] Figure 1 is a flow chart of a modular robot dynamics modeling method provided by an embodiment of the present invention;

[0106] Figure 2 is a schematic diagram of a three-dimensional model of a module unit in an embodiment of the present invention;

[0107] Figure 3 is a schematic diagram of establishing a module unit coordinate system in an embodiment of the present invention;

[0108] Figure 4 Schematic diagram of the arrangement of the module unit motion spinors in an embodiment of the present invention;

[0109] Figure 5 is the expected motion trajectory of each joint in the modular robot in the embodiment of the present invention;

[0110] Figure 6 is a driving torque curve of each joint of the first module unit calculated by the dynamic modeling method based on distributed parameter acquisition of the modular robot in an embodiment of the present invention;

[0111] Figure 7 is a driving torque curve of each joint of the second module unit calculated by the dynamic modeling method based on distributed parameter acquisition of the modular robot in an embodiment of the present invention;

[0112] Figure 8 is a driving torque curve of each joint of the third module unit calculated by the dynamic modeling method based on distributed parameter acquisition of the modular robot in an embodiment of the present invention;

[0113] Fig. 9 is a comparison diagram of the first three joint driving torques of the modular robot based on the dynamic modeling method of distributed parameter acquisition and the ADAMS software simulation results in an embodiment of the present invention;

[0114] Fig.10 It is a comparison diagram of the last three joint driving torques of the dynamic modeling method based on distributed parameter acquisition of the modular robot in an embodiment of the present invention and the ADAMS software simulation results. [Specific embodiment]

[0115] In order to better understand the technical solution of the present invention, the embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0116] It should be clear that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0117] The present invention provides a modular robot dynamics modeling method, please refer to Figure 1 , which is a flow chart of a dynamic modeling method of a modular robot based on distributed parameter acquisition provided by an embodiment of the present invention, such as Figure 1 As shown, the method comprises the following steps:

[0118] Step 101, obtaining a mathematical representation of the modular robot topology structure and a three-dimensional model of a modular unit.

[0119] Specifically, the module unit three-dimensional model is as follows Figure 2 As shown, 1 represents the connecting plane of two hemispherical shells; 2 and 18 represent two hemispherical shells; 3, 6, 11 and 15 represent the positioning device on the male interface; 4 and 14 represent the torque output shaft of the motor module of the active interface; 5 and 12 represent the motor module body on the active interface; 7, 10, 13 and 20 represent the mechanical structure components on the interface; 8, 9, 19 and 21 represent the positioning grooves on the female interface that match the positioning device; 16 represents the motor module body at the center of the module unit; 17 represents the torque output shaft of the motor module at the center of the module unit;

[0120] The topological structure of the homogeneous modular robot is mathematically represented as

[0121] M = [1,2,3]

[0122] B=[1,0,0]

[0123]

[0124] Step 102, based on the three-dimensional model of the module unit, establish the module unit body center coordinate system and the interface coordinate system, and obtain the basic kinematic parameter information and basic dynamic parameter information of the module unit.

[0125] Specifically, establish the module unit body center coordinate system. The interface coordinate system is as follows Figure 3 As shown, the motion spinor is arranged as Figure 4 As shown in the figure, the basic kinematic parameter information of the module unit includes: the screw coordinates of each rotation axis in the body-centered coordinate system; the relative posture relationship matrix between each interface coordinate system and the body-centered coordinate system Connection orientation relationship matrix when two interfaces are connected Used to indicate the specific docking status of the positioning device when the interface is docked;

[0126] According to the three-dimensional model of the module unit, the module unit structure is split to obtain each substructure of the module unit, and the centroid coordinate system of each substructure is established;

[0127] According to the three-dimensional model of the module unit, each substructure of the module unit, and the centroid coordinate system of each substructure, the basic dynamic parameters of the module unit are obtained;

[0128] The module unit structure is divided into the following 7 substructures: Figure 2 12, 17, and 18 form substructure 1; Figure 2 Among them, 11, 13, 14, and 15 form substructure 2; Figure 2 19, 20, and 21 form substructure 3; Figure 2 In the middle, 2 and 5 form substructure 4; Figure 2 3, 4, 6, and 7 form substructure 5; Figure 2 In the middle, 8, 9, and 10 form substructure 6; Figure 2 Among them, 16 constitute substructure 7;

[0129] The masses of each substructure are m1, m2, m3, m4, m5, m6, and m7 respectively; the position vectors of the center of mass of each substructure relative to the interface coordinate system or the body center coordinate system in the same direction as the center of mass coordinate system are E Pc Sub_1 , E Pc Sub_4 , E Pc Sub_7 ; The inertia tensors of each substructure relative to the mass center coordinate system are

[0130] Step 103, obtaining a module unit motion transfer library according to the module unit three-dimensional model and basic kinematic parameter information of the module unit.

[0131] Specifically, according to the three-dimensional model of the module unit, the interface arrangement, interface type, mechanical structure size, and degree of freedom arrangement information of the module unit are obtained; according to the interface arrangement and interface type of the module unit, based on the enumeration method, all connection states of the module unit are obtained through permutation and combination; according to the mechanical structure size information of the module unit and all connection states of the module unit, the connection states with structural interference are eliminated to obtain all valid connection states of the module unit; according to the degree of freedom arrangement information of the module unit and the basic kinematic parameter information of the module unit, the rotation axis and kinematic parameters contained in each valid connection state of the module unit are obtained; according to all valid connection states of the module unit and the rotation axis and kinematic parameters contained in each valid connection state of the module unit, the module unit motion transfer library is obtained. Table 1 is the module unit motion transfer library.

[0132] Table 1 Module unit motion transfer library

[0133]

[0134]

[0135] Step 104, obtaining a modular unit structural equivalent library based on the modular unit three-dimensional model, the modular unit motion transfer library, and the basic dynamic parameter information of the modular unit.

[0136] Specifically, according to the three-dimensional model of the module unit, the interface arrangement, interface type, mechanical structure size, and degree of freedom arrangement information of the module unit are obtained;

[0137] According to the interface arrangement, interface type, and mechanical structure size information of the module unit, all valid connection states of the module unit are obtained;

[0138] According to all valid connection states of the module unit, a motion input terminal interface and a motion output terminal interface of each valid connection state of the module unit are obtained;

[0139] According to the motion input terminal interface and the motion output terminal interface in each connection state of the module unit and the module unit motion transfer library, the attributes corresponding to each substructure in each effective connection state of the module unit are obtained;

[0140] According to the attributes corresponding to each substructure in each effective connection state of the module unit, the equivalent structure in each effective connection state of the module unit is obtained. Table 2 shows the corresponding numbers of the equivalent structures in each effective connection state of the module unit.

[0141] Table 2 Corresponding numbers of equivalent structures in each effective connection state of the module unit

[0142]

[0143]

[0144] According to the basic dynamic parameter information of the equivalent structure and the module unit under each effective connection state of the module unit, the dynamic parameters of the equivalent structure under each effective connection state of the module unit are obtained;

[0145] Obtain a module unit structural equivalent library according to all valid connection states of the module unit, the equivalent structure of the module unit under each valid connection state, and the dynamic parameters of the equivalent structure of the module unit under each valid connection state;

[0146] Among them, the motion input interface refers to the interface in the current module unit on the motion transmission branch of the modular robot, which is closest to the ground module unit in the current effective connection state; the motion output interface refers to the interface in the current module unit on the motion transmission branch of the modular robot, which is closest to the terminal module unit in the current effective connection state;

[0147] The attributes corresponding to each substructure in each effective connection state of the module unit are the components that transmit the motion and force of a certain rotation axis, wherein the rotation axis is determined according to the rotation axis included in the current effective connection state in the module unit motion transmission library;

[0148] The final representation of the equivalent structure in each effective connection state of the module unit is a collection of multiple equivalent structures;

[0149] The dynamic parameters of the equivalent structure under each effective connection state of the module unit include the mass of the equivalent structure, the position vector of the center of mass of the equivalent structure relative to the interface coordinate system or the body center coordinate system corresponding to the previous rotation axis, the inertia tensor of the equivalent structure, and the space inertia matrix of the equivalent structure;

[0150] The centroid coordinate system of the equivalent structure is determined as follows:

[0151] The center of mass of the equivalent structure is selected as the origin of the center of mass coordinate system, and the axis of the center of mass coordinate system is consistent with the interface coordinate system or body center coordinate system corresponding to the previous rotation axis;

[0152] The mass of the equivalent structure i for:

[0153]

[0154] Among them, m k is the mass of the modular unit substructure k in the equivalent structure i, a-b Λ i (i=1,2,3,...) is the set of module unit substructures contained in the equivalent structure i when the module unit is in the effective connection state ab, a is the motion input terminal interface of the module unit in the current effective connection state, b is the motion output terminal interface of the module unit in the current effective connection state, and a≠b;

[0155] The center of mass of the equivalent structure i relative to the interface coordinate system or body center coordinate system ΣJ corresponding to the previous rotation axis i The position vector for:

[0156]

[0157] in, is the center of mass of the module unit substructure k in the equivalent structure i in the coordinate system ΣJ i The description below can be calculated by using the basic dynamic parameters of the module unit through coordinate system transformation;

[0158] Establish the centroid coordinate system ΣL of the equivalent structure i i , the inertia tensor of the equivalent structure i is:

[0159]

[0160] in, is the inertia tensor of the module unit substructure k in the equivalent structure i in the coordinate system ΣL i The description below can be calculated by using the basic dynamic parameters of the module unit through coordinate system transformation;

[0161] The spatial inertia matrix of the equivalent structure i is:

[0162]

[0163] Step 105, obtaining the modular robot grounding module unit number, grounding interface number, and terminal module unit number according to the mathematical representation of the modular robot topological structure.

[0164] Specifically, for n topo_module The topological structure of a homogeneous modular robot with modules is mathematically represented as

[0165]

[0166] Among them, n topo_module Represents the number of modules contained in the homogeneous modular robot topology; m i (i=1,2,...,n topo_module ) represents the module numbers in the topological structure of the homogeneous modular robot; the matrix A is called the grounding relationship matrix, ba i (i=1,2,...,n topo_module ) indicates whether the module in the homogeneous modular robot topology is grounded as a base when used, ba i =0 means module m i When not grounded, i ≠0 means module m i When using ba i The interface grounding serves as the base; the matrix C is called the connection relationship matrix of the homogeneous modular robot, c ij (i=1,2,...,n topo_module ; j = 1, 2, ..., n topo_module )∈{1,...,n surf_con} indicates module m i With module m j The number of the connected interface. When i=j, c ij =0(i=1,2,...,n topo_module ; j = 1, 2, ..., n topo_module ), n surf_con represents the number of surface interfaces of a single module; the matrix O is called the connection orientation relationship matrix of the homogeneous modular robot, ij (i=1,2,...,n topo_module ; j = 1, 2, ..., n topo_module ) indicates module m i With module m j The connection orientation relationship, when i = j, co ij=0(i=1,2,...,n topo_module ; j = 1, 2, ..., n topo_module );

[0167] According to the mathematical representation of the topological structure of the homogeneous modular robot, including matrix M, matrix A, matrix C, and matrix O, the row numbers of the matrix C containing only one non-zero element, the non-zero elements in the matrix B and their locations are obtained;

[0168] According to the matrix B, the non-zero elements in the matrix B and their positions, the non-zero elements in the matrix B are the grounding interface numbers, and the elements corresponding to the positions of the non-zero elements in the matrix M are read to obtain the grounding module unit number and the grounding interface number of the homogeneous modular robot;

[0169] According to the row number of the matrix C containing only one non-zero element and the matrix M, the element at the position corresponding to the row number in the matrix M is read to obtain the terminal module unit number of the homogeneous modular robot.

[0170] It can be seen that in the homogeneous modular robot, the grounding module unit is numbered 1 and the grounding interface is numbered 1; the robot represented by the topological structure contains only one robot end, and the robot module unit is numbered 3.

[0171] Step 106, obtaining all motion transmission branches of the modular robot according to the mathematical representation of the modular robot topological structure and the modular robot grounding module unit number, grounding interface number, and terminal module unit number.

[0172] Specifically, taking the grounding interface number of the grounding module unit number of the homogeneous modular robot as the starting point and the terminal module unit number of the homogeneous modular robot as the end point, based on the matrix C in the mathematical representation of the topological structure of the homogeneous modular robot and based on the depth-first traversal, the modules and their interface information that the homogeneous modular robot needs to pass through for motion transmission from the starting point to the end point are searched to obtain all motion transmission branches of the homogeneous modular robot.

[0173] Step 107, based on all the motion transmission branches of the modular robot, obtain the connection status of the module units in each motion transmission branch and the motion transmission mode between two module units that have a connection relationship.

[0174] Specifically, there are two modes of motion transmission between two connected module units: the motion output end of the previous module unit is an interface including a motor; the motion output end of the previous module unit is an interface not including a motor.

[0175] Step 108, obtaining the module unit equivalent structure and the dynamic parameters of the equivalent structure according to the module unit structural equivalent library, the basic dynamic parameter information of the module unit and the connection state of the module unit in each motion transmission branch.

[0176] Step 109, designing a distributed parameter acquisition strategy for the modular robot based on the equivalent structure of the module unit, the dynamic parameters of the equivalent structure, and the motion transmission method between two connected module units, and acquiring the dynamic parameters corresponding to the motion transmission branch chain.

[0177] Specifically, according to the equivalent structure of the module unit, the dynamic parameters of the equivalent structure, and the motion transmission mode between two module units having a connection relationship, a dynamic parameter processing strategy corresponding to the motion transmission mode between the two module units having a connection relationship is obtained;

[0178] According to the dynamic parameter processing strategy corresponding to the motion transmission mode between two connected module units, a distributed parameter acquisition strategy for modular robots is designed to obtain the dynamic parameters corresponding to the motion transmission branch chain;

[0179] Among them, the dynamic parameter processing strategies corresponding to the motion transmission mode between two module units with a connection relationship include:

[0180] When the motion transmission mode between two connected module units is that the motion output end of the previous module unit is an interface including a motor, the initial equivalent structure of the latter module unit and the final equivalent structure of the previous module unit are recalculated according to the process of obtaining the final equivalent structure of the previous module unit;

[0181] When the motion transmission mode between two connected module units is that the motion output end of the previous module unit is an interface that does not include a motor, the end equivalent structure of the previous module unit is directly merged with the start equivalent structure of the next module unit.

[0182] Step 110, according to the equivalent structure of the modular unit, the dynamic parameters of the equivalent structure, the motion transmission method between two modular units with a connection relationship, the distributed parameter acquisition strategy of the modular robot and all the motion transmission branches of the modular robot, design a dynamic modeling method of the modular robot based on distributed parameter acquisition to obtain the dynamic model of the modular robot.

[0183] Specifically, a modular robot motion transmission chain consisting of m modular units and n degrees of freedom is subjected to an external force Under the action of

[0184]

[0185] in, is the Jacobian matrix, and Described in the same coordinate system; is the inertia force matrix, as shown below; are the Coriolis force and centrifugal force terms on each joint during the motion of the modular robot, as shown in the following formula; is the gravitational force on the modular robot during its motion, as shown in the following equation; They are the joint angle, joint angular velocity, joint angular acceleration, and driving torque vector on the current motion transmission branch chain;

[0186] One contains The dynamic model of the modular robot with a motion transmission branch chain is:

[0187]

[0188] Among them, q i , τ i They are the joint angle, joint angular velocity, joint angular acceleration, and driving torque vector on the i-th motion transmission branch. is the external force rotation amount received by the end of the i-th motion transmission branch,

[0189] By analyzing the motion transfer branch chain, it can be split into ζ non-bifurcated motion branches, and then the modular robot dynamics model can be further converted into:

[0190]

[0191] in, represents the driving torque provided by the joint of the k-th non-bifurcation motion branch during the motion of the i-th motion branch, It represents the inertial force coupling influence matrix generated by the joint motion of the j-th non-bifurcation motion branch and the joint motion of the k-th non-bifurcation motion branch during the motion of the i-th motion branch. According to the inertial force matrix M of the i-th motion branch i Obtained, represents the influence of the inertial force of the joint acceleration of the j-th non-bifurcation motion branch on the joint motion of the k-th non-bifurcation motion branch, It represents the Coriolis force and centrifugal force coupling influence matrix generated by the joint motion of the j-th non-bifurcation motion branch and the joint motion of the k-th non-bifurcation motion branch during the motion of the i-th motion branch. According to the inertia force matrix C of the i-th motion branch i Obtained, represents the influence of the acceleration of the j-th non-bifurcation motion branch joint on the Coriolis force and centrifugal force of the k-th non-bifurcation motion branch joint motion, represents the gravitational term on the joint motion of the kth non-bifurcation motion branch during the motion of the i-th motion branch, The Jacobian matrix representing the joint motion contained in the k-th branch of non-bifurcation motion relative to the i-th terminal motion;

[0192] Among them, the non-branched motion branch means that during the motion of each joint on the current branch, the transmission of motion or force has only a single direction.

[0193] According to the above method provided by the embodiment of the present invention, simulation was performed.

[0194] Design the expected motion trajectory of each joint of the modular robot. The expected motion trajectory of the joint is as follows: Figure 5 The driving torque of the modular robot when executing the desired trajectory is calculated using the dynamic modeling method of the modular robot based on distributed parameter acquisition. The driving torque of each joint of the three module units is as follows: Figure 6 , Figure 7 , Figure 8 The calculation results are compared with the ADAMS software simulation results. The comparison results are shown in Figures 9 and Fig.10 By comparison, it can be concluded that the driving torque calculated by the proposed modular robot dynamics modeling method based on distributed parameter acquisition is basically consistent with the ADAMS software simulation result, which proves the correctness and effectiveness of the modular robot dynamics modeling method based on distributed parameter acquisition.

[0195] The technical solution of the embodiment of the present invention has the following beneficial effects:

[0196] In the technical solution of the embodiment of the present invention, a mathematical representation of the topological structure of the modular robot and a three-dimensional model of the modular unit are obtained. Based on the three-dimensional model of the modular unit, a body-centered coordinate system and an interface coordinate system of the modular unit are established to obtain basic kinematic parameter information and basic dynamic parameter information of the modular unit. Based on the three-dimensional model of the modular unit and the basic kinematic parameter information of the modular unit, a modular unit motion transfer library is obtained. Based on the three-dimensional model of the modular unit, the modular unit motion transfer library and the basic dynamic parameter information of the modular unit, a modular unit structural equivalent library is obtained. Based on the mathematical representation of the topological structure of the modular robot, the grounding module unit number, the grounding interface number and the terminal module unit number of the modular robot are obtained. Based on the mathematical representation of the topological structure of the modular robot and the grounding module unit number, the grounding interface number and the terminal module unit number of the modular robot, all motion transfer branches of the modular robot are obtained. Based on all the motion transfer branches of the modular robot, the connection state of the modular units in each motion transfer branch and the motion transfer method between two modular units with a connection relationship are obtained. According to the module unit structure equivalent library, the basic dynamic parameter information of the module unit and the connection status of the module unit in each motion transmission branch, the equivalent structure of the module unit and the dynamic parameters of the equivalent structure are obtained. According to the equivalent structure of the module unit, the dynamic parameters of the equivalent structure and the motion transmission mode between two module units with a connection relationship, the distributed parameter acquisition strategy of the modular robot is designed to obtain the dynamic parameters corresponding to the motion transmission branch. According to the equivalent structure of the module unit, the dynamic parameters of the equivalent structure, the motion transmission mode between two module units with a connection relationship, the distributed parameter acquisition strategy of the modular robot and all motion transmission branches of the modular robot, the dynamic modeling method of the modular robot based on distributed parameter acquisition is designed to obtain the dynamic model of the modular robot. Therefore, the dynamic modeling of the modular robot can be realized. Combined with the characteristics of the modular robot, based on the dynamic parameters of the module unit, more efficient dynamic modeling of the homogeneous modular robot is realized, providing a model basis for the application of modular robots.

[0197] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

[0198] The contents not described in detail in the specification of the present invention belong to the common knowledge of those skilled in the art.

Claims

1. A modular robot dynamics modeling method, characterized in that: The method comprises: Obtain the mathematical representation of the modular robot topology and the three-dimensional model of the module unit; According to the three-dimensional model of the module unit, the module unit body center coordinate system and interface coordinate system are established to obtain the basic kinematic parameter information and basic dynamic parameter information of the module unit; According to the three-dimensional model of the module unit and the basic kinematic parameter information of the module unit, a module unit motion transfer library is obtained; According to the three-dimensional model of the module unit, the module unit motion transfer library, and the basic dynamic parameter information of the module unit, the module unit structure equivalent library is obtained; According to the mathematical representation of the modular robot topological structure, the modular robot grounding module unit number, grounding interface number, and terminal module unit number are obtained; According to the mathematical representation of the modular robot topological structure and the modular robot grounding module unit number, grounding interface number, and terminal module unit number, all motion transmission branches of the modular robot are obtained; According to all motion transmission branches of the modular robot, the connection state of the module units in each motion transmission branch and the motion transmission mode between two module units with a connection relationship are obtained; According to the module unit structure equivalent library, the basic dynamic parameter information of the module unit and the connection state of the module unit in each motion transmission branch chain, the module unit equivalent structure and the dynamic parameters of the equivalent structure are obtained; According to the equivalent structure of the module unit, the dynamic parameters of the equivalent structure, and the motion transmission mode between two connected module units, a distributed parameter acquisition strategy for the modular robot is designed to obtain the dynamic parameters corresponding to the motion transmission branch chain; According to the equivalent structure of the modular unit, the dynamic parameters of the equivalent structure, the motion transmission method between two connected modular units, the distributed parameter acquisition strategy of the modular robot and all the motion transmission branches of the modular robot, a dynamic modeling method of the modular robot based on distributed parameter acquisition is designed to obtain the dynamic model of the modular robot.

2. The method according to claim 1, characterized in that According to the three-dimensional model of the module unit, the module unit body center coordinate system and interface coordinate system are established to obtain the basic kinematic parameter information and basic dynamic parameter information of the module unit, including: According to the three-dimensional model of the module unit, the module unit body center coordinate system and interface coordinate system are established to obtain the basic kinematic parameter information of the module unit; According to the three-dimensional model of the module unit, the module unit structure is split to obtain each substructure of the module unit, and the centroid coordinate system of each substructure is established; The basic dynamic parameters of the module unit are obtained according to the three-dimensional model of the module unit, each substructure of the module unit, and the centroid coordinate system of each substructure.

3. The method according to claim 2, characterized in that According to the three-dimensional model of the module unit, the module unit body center coordinate system and interface coordinate system are established to obtain the basic kinematic parameter information of the module unit, including: The spinor coordinates of each rotation axis in the body-centered coordinate system; The relative position relationship matrix between each interface coordinate system and the body center coordinate system; The connection orientation relationship matrix existing when two interfaces are connected is used to indicate the specific docking status of the positioning device when the interfaces are docked.

4. The method according to claim 2, characterized in that: According to the three-dimensional model of the module unit, the module unit structure is split to obtain the substructures of the module unit, and the centroid coordinate system of each substructure is established, including: The following rules apply to splitting the module unit structure: The parts connected to the rotor of the motor in the interface can be assembled into a substructure, the parts connected to the stator of the motor in the interface can be assembled into a substructure, the parts connected to the rotor of the motor in the body center can be assembled into a substructure, and the parts connected to the stator of the motor in the body center can be assembled into a substructure; The method for determining the centroid coordinate system of each substructure of the module unit is: The centroid of each substructure is selected as the origin of the centroid coordinate system. The selection of the axis of the centroid coordinate system of each substructure follows the following rules: For the substructure assembled from the parts that are fixedly connected to the rotor of the motor in the interface, the axial direction of its centroid coordinate system is consistent with the interface coordinate system; For the substructure assembled from the components fixedly connected to the stator of the motor in the interface, the axial direction of the centroid coordinate system is consistent with the body-centroid coordinate system; For the substructure assembled from the parts fixedly connected to the rotor of the motor in the body center, the axial direction of its centroid coordinate system is consistent with the body center coordinate system; For a substructure assembled from components that are fixedly connected to the stator of the motor in the body center, the axial direction of its centroid coordinate system is consistent with the body center coordinate system.

5. The method according to claim 2, characterized in that: According to the three-dimensional model of the module unit, each substructure of the module unit, and the centroid coordinate system of each substructure, the basic dynamic parameters of the module unit are obtained, including: The quality of each substructure; The position vector of the center of mass of each substructure relative to the interface coordinate system or the body center coordinate system which is in the same direction as the center of mass coordinate system; The inertia tensor of each substructure relative to the center-of-mass coordinate system.

6. The method according to claim 1, characterized in that According to the three-dimensional model of the module unit and the basic kinematic parameter information of the module unit, the module unit motion transfer library is obtained, including: According to the three-dimensional model of the module unit, the interface arrangement, interface type, mechanical structure size, and degree of freedom arrangement information of the module unit are obtained; According to the interface arrangement, interface type, and mechanical structure size information of the module unit, all valid connection states of the module unit are obtained; According to the degree of freedom arrangement information of the module unit and the basic kinematic parameter information of the module unit, the rotation axis and kinematic parameters contained in each effective connection state of the module unit are obtained; According to all effective connection states of the module unit, the rotation axis and kinematic parameters contained in each effective connection state of the module unit, a module unit motion transfer library is obtained.

7. The method according to claim 6, characterized in that According to the interface arrangement, interface type, and mechanical structure size information of the module unit, all valid connection states of the module unit are obtained, including: According to the interface arrangement and interface type of the module unit, based on the enumeration method, all connection states of the module unit are obtained through permutations and combinations; According to the mechanical structure dimension information of the module unit and all the connection states of the module unit, the connection states with structural interference are eliminated to obtain all the valid connection states of the module unit.

8. The method according to claim 1, characterized in that Based on the modular unit three-dimensional model, the modular unit motion transfer library, and the basic dynamic parameter information of the modular unit, the modular unit structure equivalent library is obtained, including: According to the three-dimensional model of the module unit, the interface arrangement, interface type, mechanical structure size, and degree of freedom arrangement information of the module unit are obtained; According to the interface arrangement, interface type, and mechanical structure size information of the module unit, all valid connection states of the module unit are obtained; According to all valid connection states of the module unit, a motion input terminal interface and a motion output terminal interface of each valid connection state of the module unit are obtained; According to the motion input terminal interface and the motion output terminal interface in each connection state of the module unit and the module unit motion transfer library, the attributes corresponding to each substructure in each effective connection state of the module unit are obtained; According to the attributes corresponding to each substructure in each effective connection state of the module unit, the equivalent structure in each effective connection state of the module unit is obtained; According to the basic dynamic parameter information of the equivalent structure and the module unit under each effective connection state of the module unit, the dynamic parameters of the equivalent structure under each effective connection state of the module unit are obtained; Obtain a module unit structural equivalent library according to all valid connection states of the module unit, the equivalent structure of the module unit under each valid connection state, and the dynamic parameters of the equivalent structure of the module unit under each valid connection state; Among them, the motion input interface refers to the interface in the current module unit on the motion transmission branch of the modular robot, which is closest to the ground module unit in the current effective connection state; the motion output interface refers to the interface in the current module unit on the motion transmission branch of the modular robot, which is closest to the terminal module unit in the current effective connection state; The attributes corresponding to each substructure in each effective connection state of the module unit are the components that transmit the motion and force of a certain rotation axis, wherein the rotation axis is determined according to the rotation axis included in the current effective connection state in the module unit motion transmission library; The final representation of the equivalent structure in each effective connection state of the module unit is a collection of multiple equivalent structures; The dynamic parameters of the equivalent structure under each effective connection state of the module unit include the mass of the equivalent structure, the position vector of the center of mass of the equivalent structure relative to the interface coordinate system or the body center coordinate system corresponding to the previous rotation axis, the inertia tensor of the equivalent structure, and the space inertia matrix of the equivalent structure; The centroid coordinate system of the equivalent structure is determined as follows: The center of mass of the equivalent structure is selected as the origin of the center of mass coordinate system, and the axis of the center of mass coordinate system is consistent with the interface coordinate system or body center coordinate system corresponding to the previous rotation axis; The mass of the equivalent structure i for: Among them, m k is the mass of the modular unit substructure k in the equivalent structure i, a-b Λ i (i=1,2,3,...) is the set of module unit substructures contained in the equivalent structure i when the module unit is in the effective connection state ab, a is the motion input terminal interface of the module unit in the current effective connection state, b is the motion output terminal interface of the module unit in the current effective connection state, and a≠b; The center of mass of the equivalent structure i relative to the interface coordinate system or body center coordinate system ΣJ corresponding to the previous rotation axis i The position vector for: in, is the center of mass of the module unit substructure k in the equivalent structure i in the coordinate system ΣJ i The description below can be calculated by using the basic dynamic parameters of the module unit through coordinate system transformation; Establish the centroid coordinate system ΣL of the equivalent structure i i , the inertia tensor of the equivalent structure i is: in, is the inertia tensor of the module unit substructure k in the equivalent structure i in the coordinate system ΣL i The description below can be calculated by using the basic dynamic parameters of the module unit through coordinate system transformation; The spatial inertia matrix of the equivalent structure i is: Among them, 0 3×3 is a zero matrix of dimension 3×3, I 3×3 is the unit matrix of dimension 3×3.

9. The method according to claim 1, characterized in that: According to the mathematical representation of the modular robot topological structure, the modular robot grounding module unit number, grounding interface number, and terminal module unit number are obtained, including: For n topo_module The modular robot topology structure of modules is mathematically represented as Among them, n topo_module Represents the number of modules contained in the modular robot topology; m i (i=1,2,...,n topo_module ) represents the module numbers in the modular robot topology; matrix B is called the grounding relationship matrix, ba i (i=1,2,...,n topo_module ) indicates whether the module in the modular robot topology is grounded as a base when used, ba i =0 means module m i When not grounded, i ≠0 means module m i When using i The interface ground is used as the base; the matrix C is called the connection relationship matrix of the modular robot, c ij (i=1,2,...,n topo_module ; j = 1, 2, ..., n topo_module )∈{1,...,n surf_con } indicates module m i With module m j The number of the connected interface. When i=j, c ij =0(i=1,2,...,n topo_module ; j = 1, 2, ..., n topo_module ), n surf_con represents the number of surface interfaces of a single module; the matrix O is called the connection orientation relationship matrix of the modular robot, ij (i=1,2,...,n topo_module ; j = 1, 2, ..., n topo_module ) indicates module m i With module m j The connection orientation relationship, when i = j, co ij =0(i=1,2,...,n topo_module ; j = 1, 2, ..., n topo_module ); According to the mathematical representation of the modular robot topology structure, including matrix M, matrix A, matrix C, and matrix O, the row numbers of the matrix C containing only one non-zero element, the non-zero elements in the matrix A and their positions are obtained; According to the matrix A, the non-zero elements in the matrix A and their positions, the non-zero elements in the matrix A are the grounding interface numbers, and the elements corresponding to the positions of the non-zero elements in the matrix M are read to obtain the modular robot grounding module unit number and the grounding interface number; According to the row number containing only one non-zero element in the matrix C and the matrix M, the element at the position corresponding to the row number in the matrix M is read to obtain the terminal module unit number of the modular robot.

10. The method according to claim 1, characterized in that According to the mathematical representation of the modular robot topological structure and the modular robot grounding module unit number, grounding interface number, and terminal module unit number, all motion transmission branches of the modular robot are obtained, including: Taking the grounding interface number of the modular robot's grounding module unit number as the starting point and the modular robot's terminal module unit number as the end point, based on the matrix C in the mathematical representation of the modular robot's topological structure, based on depth-first traversal, the modules and their interface information that the modular robot needs to pass through for motion transmission from the starting point to the end point are searched to obtain all the motion transmission branches of the modular robot.

11. The method according to claim 1, characterized in that According to all motion transmission branches of the modular robot, the connection status of the module units in each motion transmission branch and the motion transmission mode between two module units with a connection relationship are obtained, including: There are two ways of motion transmission between two connected module units: The motion output of the previous module unit is an interface including a motor; The motion output of the preceding module unit is an interface without a motor.

12. The method according to claim 1, characterized in that According to the equivalent structure of the module unit, the dynamic parameters of the equivalent structure, and the motion transmission mode between two connected module units, a distributed parameter acquisition strategy for modular robots is designed to obtain the dynamic parameters corresponding to the motion transmission branch chain, including: According to the equivalent structure of the module unit, the dynamic parameters of the equivalent structure, and the motion transmission mode between two module units having a connection relationship, a dynamic parameter processing strategy corresponding to the motion transmission mode between the two module units having a connection relationship is obtained; According to the dynamic parameter processing strategy corresponding to the motion transmission mode between two connected module units, a distributed parameter acquisition strategy for modular robots is designed to obtain the dynamic parameters corresponding to the motion transmission branch chain; Among them, the dynamic parameter processing strategies corresponding to the motion transmission mode between two module units with a connection relationship include: When the motion transmission mode between two connected module units is that the motion output end of the previous module unit is an interface including a motor, the initial equivalent structure of the latter module unit and the final equivalent structure of the previous module unit are recalculated according to the process of obtaining the final equivalent structure of the previous module unit; When the motion transmission mode between two connected module units is that the motion output end of the previous module unit is an interface that does not include a motor, the end equivalent structure of the previous module unit is directly merged with the start equivalent structure of the next module unit.

13. The method according to claim 1, characterized in that According to the equivalent structure of the module unit, the dynamic parameters of the equivalent structure, the motion transmission mode between two connected module units, the distributed parameter acquisition strategy of the modular robot and all the motion transmission branches of the modular robot, the dynamic modeling method of the modular robot based on distributed parameter acquisition is designed to obtain the dynamic model of the modular robot, including: A modular robot motion transmission chain consisting of m modular units and n degrees of freedom is subjected to external force rotation. Under the action of in, is the Jacobian matrix, and Described in the same coordinate system; is the inertia force matrix, as shown below; are the Coriolis force and centrifugal force terms on each joint during the motion of the modular robot, as shown in the following formula; is the gravitational force on the modular robot during its motion, as shown in the following equation; They are the joint angle, joint angular velocity, joint angular acceleration, and driving torque vector on the current motion transmission branch chain; One contains The dynamic model of the modular robot with a motion transmission branch chain is: Among them, q i , τ i They are the joint angle, joint angular velocity, joint angular acceleration, and driving torque vector on the i-th motion transmission branch. is the external force rotation amount received by the end of the i-th motion transmission branch, By analyzing the motion transfer branch chain, it can be split into ζ non-bifurcated motion branches, and then the modular robot dynamics model can be further converted into: in, represents the driving torque provided by the joint of the k-th non-bifurcation motion branch during the motion of the i-th motion branch, It represents the inertial force coupling influence matrix generated by the joint motion of the j-th non-bifurcation motion branch and the joint motion of the k-th non-bifurcation motion branch during the motion of the i-th motion branch. According to the inertial force matrix M of the i-th motion branch i Obtained, represents the influence of the inertial force of the joint acceleration of the j-th non-bifurcation motion branch on the joint motion of the k-th non-bifurcation motion branch, It represents the Coriolis force and centrifugal force coupling influence matrix generated by the joint motion of the j-th non-bifurcation motion branch and the joint motion of the k-th non-bifurcation motion branch during the motion of the i-th motion branch. According to the inertia force matrix C of the i-th motion branch i Obtained, represents the influence of the acceleration of the j-th non-bifurcation motion branch joint on the Coriolis force and centrifugal force of the k-th non-bifurcation motion branch joint motion, represents the gravitational term on the joint motion of the kth non-bifurcation motion branch during the motion of the i-th motion branch, The Jacobian matrix representing the joint motion contained in the k-th non-bifurcation motion branch relative to the i-th terminal motion; Among them, the non-branched motion branch means that during the motion of each joint on the current branch, the transmission of motion or force has only a single direction.

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