A core mold posture control method and system adapted to time-varying loads of weaving

Abstract

The present invention relates to the field of intelligent weaving technology, specifically to a core mold posture control method and system adapted to time-varying loads of weaving, the method comprising the following steps: establishing a core shaft end face coordinate system according to a main robot, and obtaining a coordinate system geometric relationship in combination with the coordinate system: establishing a core shaft center of mass generalized analysis model according to the relative motion relationship, coordinate system and geometric relationship of weaving; obtaining a rigid body dynamics model by combining the core shaft center of mass generalized analysis model and the yarn drop point stage, and analyzing the core mold center of mass generalized analysis results by the rigid body dynamics model to determine the input force required by the robot; constructing a dual-robot co-supporting core mold model, and obtaining the generalized force at the core mold center of mass according to the input force required by the robot and the dual-robot co-supporting core mold model; constructing a robot joint speed analytical model according to the generalized force at the core mold center of mass, and optimizing the robot control parameters using the analytical model. The present invention optimizes the parameters according to the execution force and weaving motion.

Description

Technical Field

[0001] The present invention relates to the field of intelligent weaving technology, and in particular to a core mold posture control method and system adapted to time-varying loads during weaving. Background Art

[0002] Due to the large size and complex shape of the mandrel, its weight will also increase significantly, and higher requirements will be placed on the support and fixation of the mandrel. During the weaving process, due to the influence of gravity, the yarn is subjected to greater resistance and friction when deposited. At the same time, a large number of yarns need to be woven onto the mandrel synchronously. The density and mutual entanglement of the yarns further increase the complexity and resistance of weaving. Not only does it increase the difficulty of weaving, but it also brings challenges to the performance of weaving equipment, the stability of the process and the production cost.

[0003] Therefore, it is particularly important to optimize the operational performance of flexible robots under time-varying load conditions. Improving the operational stability and efficiency of robots in complex situations such as handling heavy weights and multiple yarns can greatly improve the weaving process, reduce resistance, and improve weaving quality, thereby providing solid technical support for the widespread promotion and application of flexible robots in practical applications. Therefore, it is necessary to optimize the operability of flexible robots under time-varying loads to solve the challenges faced in the weaving process of large-sized and complex-shaped mandrels, and to promote the further development of flexible robot technology. Summary of the invention

[0004] In view of the defects of the existing methods and the shortcomings of practical applications, the first aspect of the present invention provides a core mold posture control method that adapts to the time-varying load of weaving, which includes the following steps: establishing a core shaft end face coordinate system based on the main robot, and obtaining the coordinate system geometric relationship in combination with the core shaft end face coordinate system: establishing a core shaft center of mass generalized analysis model according to the relative motion relationship of weaving, the core shaft end face coordinate system and the coordinate system geometric relationship; combining the core shaft center of mass generalized analysis model and the yarn landing stage to obtain a rigid body dynamics model, and analyzing the core mold center of mass generalized analysis results through the rigid body dynamics model to determine the input force required by the robot; constructing a dual robot co-supporting core mold model, and obtaining the generalized force at the core mold center of mass according to the input force required by the robot and the dual robot co-supporting core mold model; constructing a robot joint speed analysis model according to the generalized force at the core mold center of mass, and optimizing the robot control parameters using the robot joint speed analysis model. The present invention establishes a coordinate system based on the robot, and optimizes the robot control parameters in combination with relevant models and relationships to ensure that the robot can apply accurate input force during the weaving process, which is of great significance for improving the accuracy, stability and production efficiency of the weaving process.

[0005] Optionally, the establishing of the spindle end face coordinate system based on the main robot and obtaining the coordinate system geometric relationship in combination with the spindle end face coordinate system comprises: establishing the spindle end face coordinate system, the spindle end face coordinate system comprising a world coordinate system, a spindle centroid local coordinate system and a guide ring coordinate system; analyzing the coordinate system geometric relationship based on the world coordinate system, the spindle centroid local coordinate system and the guide ring coordinate system;

[0006] The geometric relationship of the coordinate system satisfies the following relationship:

[0007]

[0008] in, Indicates the spatial position of the origin of the guide ring coordinate system in the world coordinate system. express t The spatial position of the origin of the center of mass coordinate system of the mandrel in the world coordinate system at the moment, Indicates the coordinate system of the center of mass of the mandrel j The location information corresponding to each trajectory point, express t The pulling speed of the core mold at this moment, The coordinate system of the present invention accurately describes the position of the mandrel and the guide ring in the global space, and can optimize the production process and improve production efficiency through accurate position description and dynamic relationship analysis to ensure product quality and consistency.

[0009] Optionally, the establishing of a generalized analysis model of the center of mass of the mandrel according to the relative motion relationship of weaving, the coordinate system of the end face of the mandrel and the geometric relationship of the coordinate system comprises: establishing a generalized analysis model of the center of mass of the mandrel according to the relative motion relationship of weaving, the coordinate system of the end face of the mandrel and the geometric relationship of the coordinate system; obtaining a generalized analysis result of the center of mass of the core mold based on the generalized analysis model of the center of mass of the mandrel;

[0010] The generalized analysis model of the mandrel centroid satisfies the following relationship:

[0011] in, represents the generalized linear velocity of the center of mass of the core mode, represents the relative angular velocity of the guide ring in the coordinates of the center of mass of the core model, Represents the position vector of the midpoint of the guide ring in the center-of-mass coordinate system of the core mold, It represents the relative linear velocity of the guide ring under the coordinates of the center of mass of the core mold, represents the relative acceleration of the guide ring in the coordinates of the center of mass of the core model, Indicates the core mold movement time, represents the generalized angular velocity of the center of mass of the core mode, represents the generalized acceleration of the center of mass of the core model, represents the relative angular acceleration of the guide ring in the coordinates of the center of mass of the core model, Indicates the changing speed of the position of the midpoint of the guide ring in the center-of-mass coordinate system of the core mold, The invention monitors the motion state of the mandrel in real time based on the model, including but not limited to position, speed, acceleration, etc., which is of great significance for timely discovering and solving problems, optimizing production processes and improving production efficiency.

[0012] Optionally, it is characterized in that the rigid body dynamics model obtained by combining the core shaft mass center generalized analysis model and the yarn landing stage includes: establishing a yarn landing deposition stage model and a yarn landing forced deposition stage model according to the yarn landing stage; the yarn landing deposition stage model satisfies the following relationship:

[0013] in, Represents the vector pointing to the outside of the core axis on the triangle patch where the landing point is located. express k The intersection of the yarn and the guide ring at the moment, express k The point where the water drops on the mandrel surface at the moment;

[0014] The yarn drop point forced deposition stage model satisfies the following relationship:

[0015]

[0016] in, Indicates the yarn tension. express k The intersection of the forced deposition yarn and the guide ring at the moment, express k The point where the yarn is forced to settle at the moment, express k Time next n-1 The spatial position of the intersection point, express k Time next n+1 The spatial position of the intersection point, express k Time next n The invention combines the generalized analysis model of the center of mass of the mandrel and the rigid body dynamics model to help improve the accuracy, stability and product quality of the weaving process.

[0017] Optionally, the obtaining of the rigid body dynamics model by combining the core shaft mass center generalized analysis model and the yarn drop point stage includes: obtaining the rigid body dynamics model by using the yarn drop point deposition stage model and the yarn drop point forced deposition stage model; the rigid body dynamics model satisfies the following relationship:

[0018]

[0019] in, represents the generalized force at the center of mass of the core model, Represents the diagonal matrix of the 3*3 rigid body mass, Represents the inertia matrix of a 3*3 rigid body, represents the generalized acceleration of the center of mass of the core model, represents the generalized angular acceleration of the center of mass of the core mode, represents the generalized angular velocity of the center of mass of the core mode, represents the acceleration due to gravity, The present invention monitors and analyzes the parameters in the rigid body dynamics model in real time, can grasp the movement state and force condition of the mandrel, and helps to timely discover potential problems, such as abnormal yarn tension, unstable mandrel movement, etc., so as to take timely measures to make adjustments.

[0020] Optionally, the construction of the dual-robot jointly holding core mold model satisfies the following relationship: a dual-robot jointly holding core mold model is established based on the core shaft end face coordinate system, and the dual robots include a master robot and a slave robot;

[0021] The dual robots jointly support the core model, satisfying the following relationship:

[0022]

[0023] in, Represents the rotation matrix from the world coordinate system to the end of the robot, Represents the rotation matrix from the world coordinate system to the origin of the linear guide, Represents the rotation matrix from the origin of the linear guide to the robot base, represents the moving distance of the linear guides of the two robots, represents the robot's joint motion angle, The dual robots of the present invention jointly hold the core mold to speed up the processing or weaving speed. In addition, the movement trajectory and collaborative working mode of the robots are optimized, which can further reduce the production time and improve the production efficiency.

[0024] Optionally, the generalized force at the center of mass of the core mold obtained according to the input force required by the robot and the dual robots jointly holding the core mold model includes: the generalized force at the center of mass of the core mold satisfies the following relationship:

[0025]

[0026] in, represents the generalized force at the center of mass of the core model, represents the pseudo-inverse matrix of the Jacobian matrix of the master robot, represents the pseudo-inverse matrix of the Jacobian matrix from the robot, represents the generalized driving force of the main robot's dual-arm joints, Represents the generalized driving force from the robot's double arm joints. The present invention can accurately control the holding force and motion state of the dual robots on the core mold through the generalized force at the core mold mass center, which helps to ensure the stability and accuracy of the core mold during processing or weaving, thereby improving product quality.

[0027] Optionally, constructing the robot joint velocity analytical model based on the generalized force at the center of mass of the core model includes: mapping the generalized force at the center of mass of the core model to the operating space to obtain a force generalized force operable ellipsoid, the force generalized force operable ellipsoid includes a force operable ellipsoid and a torque operable ellipsoid; combining the operable ellipsoid and the torque operable ellipsoid to construct the robot joint velocity analytical model. The present invention can obtain more accurate force operable ellipsoid and torque operable ellipsoid by mapping the generalized force at the center of mass of the core model to the operating space. The above two ellipsoids provide detailed information about the robot's operating ability, which helps to achieve precise control of the robot's movement at the joint velocity level.

[0028] Optionally, the robot joint velocity analytical model is constructed to satisfy the following relationship:

[0029]

[0030] in, Indicates the speed of the linear guide and robot joints, represents a diagonal positive definite weight matrix, represents the pseudo-inverse matrix of the Jacobian matrix of a single robot, represents the robot Jacobian matrix, represents the generalized velocity of the robot end, represents the operability optimization weight, represents the identity matrix, represents the pseudo-inverse matrix of the robot Jacobian matrix, Represents any vector in the null space of the Jacobian matrix. The robot joint velocity analytical model constructed by the present invention has the advantages of quantitative operation capability, convenience for debugging and verification, and support for control strategies, so that the model has a wide range of application prospects in the field of robotics.

[0031] In the second aspect, the present invention also provides a core mold posture control system that adapts to the time-varying load of weaving, which can efficiently execute a core mold posture control method that adapts to the time-varying load of weaving provided by the present invention, the system includes an input device, a processor, an output device and a memory, wherein the input device, the processor, the output device and the memory are interconnected, the memory includes a computer-readable storage medium as described in the first aspect of the present invention, the memory is used to store a computer program, the computer program includes program instructions, and the processor is configured to call the program instructions. The system provided by the present invention has a compact structure, strong applicability, and greatly improves the operating efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a flow chart of the core mold posture control method adapting to the time-varying load of weaving of the present invention;

[0033] Figure 2 A schematic diagram of the relationship between the mandrel end face coordinate system of the mandrel mold posture control method adapted to the time-varying load of weaving according to the present invention;

[0034] Figure 3 A schematic diagram of the yarn deposition mechanism of the core mold posture control method adapted to the time-varying load of weaving according to the present invention;

[0035] Figure 4 A schematic diagram of yarn deposition process prediction of the core mold posture control method adapted to time-varying loads during weaving according to the present invention;

[0036] Figure 5 Schematic diagram of the dual-robot kinematic model of the core mold posture control method of the present invention that adapts to the time-varying load of weaving;

[0037] Figure 6 A schematic diagram of a robot control parameter optimization framework of a core mold posture control method adapted to time-varying weaving loads of the present invention;

[0038] Figure 7 A schematic structural diagram of a core mold posture control system of the present invention that adapts to time-varying loads during weaving. DETAILED DESCRIPTION

[0039] The specific embodiments of the present invention will be described in detail below. It should be noted that the embodiments described herein are only for illustration and are not intended to limit the present invention. In the following description, a large number of specific details are set forth in order to provide a thorough understanding of the present invention. However, it is obvious to those of ordinary skill in the art that these specific details do not need to be adopted to implement the present invention. In other examples, in order to avoid confusing the present invention, known circuits, software or methods are not specifically described.

[0040] Throughout the specification, references to "one embodiment," "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in conjunction with the embodiment or example is included in at least one embodiment of the present invention. Therefore, the phrases "in one embodiment," "in an embodiment," "an example," or "an example" appearing in various places throughout the specification do not necessarily all refer to the same embodiment or example. In addition, particular features, structures, or characteristics may be combined in one or more embodiments or examples in any suitable combination and / or subcombination. In addition, it should be understood by those of ordinary skill in the art that the figures provided herein are for illustrative purposes and that the figures are not necessarily drawn to scale.

[0041] See also Figure 1 Due to the heavy load of the large-sized and complex-shaped mandrel and the high yarn density during the weaving process, the resistance generated is significant. The dual-robot traction system of the present invention needs to monitor the end force in real time and dynamically adjust its control parameters to optimize the joint position to ensure the smooth progress of the weaving process. The present invention provides a mandrel posture control method that adapts to the time-varying load of weaving, and the mandrel posture control method that adapts to the time-varying load of weaving includes the following steps:

[0042] S1. Establish the mandrel end face coordinate system based on the main robot, and obtain the coordinate system geometric relationship by combining the mandrel end face coordinate system. The specific implementation steps and related contents are as follows:

[0043] Establish the mandrel end face coordinate system. In the embodiment, the mandrel end face coordinate system mainly includes the world coordinate system, the mandrel centroid local coordinate system and the guide ring coordinate system. The specific implementation content is as follows:

[0044] First, the relevant actions of the guide ring need to be mapped to the position of the center of mass of the mandrel in the world coordinate system. Then, based on the actual force exerted by the yarn on the mandrel during the weaving process and the relevant dynamic equations, the resultant force that the dual robots need to provide can be determined to ensure that the mandrel moves according to the expected design to maintain the stability of the mandrel movement.

[0045] In this embodiment, a global reference system, namely the world coordinate system, is set at the zero point position of the linear guide rail of the main robot. ,The world coordinate system is used to define and track the global position and orientation of all objects and ,actions in the system.

[0046] A dynamically changing coordinate system is established at the center of mass of the mandrel , which refers to the local coordinate system of the center of mass of the mandrel. The above dynamic coordinate system will move and rotate with the movement of the mandrel and can be used to describe the real-time position and posture of the mandrel during the movement.

[0047] At the same time, a fixed coordinate system is established on the guide ring , which refers to the guide ring coordinate system. The guide ring coordinate system is closely related to the guide ring and can be used to describe the fixed position and posture of the guide ring, as well as the relative position relationship between the fixed coordinate system and the core axis and the world coordinate system.

[0048] In the embodiment, the world coordinate system, the local coordinate system of the center of mass of the mandrel, and the guide ring coordinate system together constitute a reference frame for describing and analyzing the motion of the system. The relative position and posture relationship between the coordinate systems can accurately describe the motion state of the mandrel and the guide ring, as well as their interaction with the main robot and the world. For details on the coordinate system, please refer to Figure 2 .

[0049] According to the above-mentioned world coordinate system, the local coordinate system of the center of mass of the mandrel and the guide ring coordinate system, the geometric relationship of the coordinate system is analyzed. The specific implementation content is as follows:

[0050] In the core shaft end face coordinate system, the guide ring not only rotates around the core shaft axis, but may also translate in a direction perpendicular to the core shaft axis, thereby changing the relative position between the guide ring and the core shaft.

[0051] The geometric relationship between the coordinate systems in the embodiment is mainly reflected in two aspects: one is the rotation relationship, that is, the rotation angle and rotation direction of the guide ring coordinate system relative to the core shaft end face coordinate system; the other is the translation relationship, that is, the translation distance and direction of the guide ring coordinate system in the core shaft end face coordinate system. In an optional embodiment, when the guide ring rotates around the core shaft axis, its coordinate system will rotate relative to the core shaft end face coordinate system, forming a rotation matrix, which can be used to describe the rotation relationship between the two; when the guide ring moves in a direction perpendicular to the core shaft axis, its coordinate system will translate relative to the core shaft end face coordinate system, forming a translation vector, which can be used to describe the translation relationship between the two.

[0052] In order to accurately describe the motion state of the guide ring during the weaving process, it is necessary to consider its rotational motion and translational motion at the same time and clarify the geometric relationship between them and the core shaft end face coordinate system, which is helpful to understand and analyze the motion characteristics of the guide ring and the interaction between other system components.

[0053] The geometric relationship of the above coordinate system satisfies the following relationship:

[0054]

[0055] in, Indicates the spatial position of the origin of the guide ring coordinate system in the world coordinate system. express tThe spatial position of the origin of the center of mass coordinate system of the mandrel in the world coordinate system at the moment, Indicates the coordinate system of the center of mass of the mandrel j The location information corresponding to each trajectory point, express t The pulling speed of the core mold at this moment, Indicates the pulling time of the core mold.

[0056] Furthermore, in the present embodiment, the method for analyzing the geometric relationship of the coordinate system is only an optional condition of the present invention. In one or some other embodiments, the method for generating the geometric relationship of the coordinate system can be flexibly selected according to the product weaving requirements and the coordinate system construction conditions. The method for analyzing the geometric relationship of the coordinate system can be flexibly selected, so that the solution proposed by the present invention is more competitive and practical in practical applications.

[0057] S2. A generalized analysis model of the center of mass of the mandrel is established based on the relative motion relationship of weaving, the coordinate system of the mandrel end face, and the geometric relationship of the coordinate system. The specific implementation steps and related contents are as follows:

[0058] According to the relative motion relationship of weaving, the coordinate system of the mandrel end face and the geometric relationship of the coordinate system, a generalized analysis model of the mandrel centroid is established. The specific implementation content is as follows:

[0059] Based on relevant knowledge of physics and engineering, in this embodiment, when the above-mentioned core shaft moves relative to the guide ring in the world coordinate system, if the guide ring is a fixed structure in the world coordinate system, then the core shaft speed is 0 relative to the world coordinate system.

[0060] In order to further describe the position, velocity, acceleration and other information of an object in a multi-dimensional space, the generalized velocity and generalized acceleration at the center of mass of the core shaft are analyzed in the embodiment, wherein the true velocity of the guide ring relative to the world coordinate system is 0, the generalized velocity at the center of mass of the core shaft is the velocity of the core shaft relative to the world coordinate system; the generalized acceleration at the center of mass of the core shaft is the rate of change of the center of mass velocity of the core shaft with time.

[0061] Based on the generalized analysis model of the mandrel centroid, the generalized analysis result of the mandrel centroid can be obtained, and the above generalized analysis model of the mandrel centroid satisfies the following relationship:

[0062]

[0063] in, represents the generalized linear velocity of the center of mass of the core mode, represents the relative angular velocity of the guide ring in the coordinates of the center of mass of the core model, Represents the position vector of the midpoint of the guide ring in the center-of-mass coordinate system of the core mold, It represents the relative linear velocity of the guide ring under the coordinates of the center of mass of the core mold, represents the relative acceleration of the guide ring in the coordinates of the center of mass of the core model, Indicates the core mold movement time, represents the generalized angular velocity of the center of mass of the core mode, represents the generalized acceleration of the center of mass of the core model, represents the relative angular acceleration of the guide ring in the coordinates of the center of mass of the core model, Indicates the changing speed of the position of the midpoint of the guide ring in the center-of-mass coordinate system of the core mold, represents the generalized angular acceleration of the center of mass of the core mode.

[0064] In the embodiment, setting the speed of the guide ring to 0 can simplify the relevant calculation process. When it is necessary to calculate the position or speed of other moving objects relative to the guide ring, only the motion state of those objects needs to be considered, without considering the motion of the guide ring.

[0065] Furthermore, the method for establishing the generalized analysis model of the core shaft centroid in the present embodiment is only an optional condition of the present invention. In one or some other embodiments, the method for constructing the generalized analysis model of the core shaft centroid can be changed according to the coordinate construction situation and the position situation. Flexible selection or adjustment of the method for constructing the generalized analysis model of the core shaft centroid according to the specific situation can ensure a high degree of match between the model and the actual application scenario, thereby improving the adaptability and accuracy of the model.

[0066] S3. Combine the generalized analysis model of the mandrel center of mass and the yarn drop point stage to obtain a rigid body dynamics model. The generalized analysis results of the mandrel center of mass are analyzed by the rigid body dynamics model to determine the input force required by the robot. The specific implementation steps and related contents are as follows:

[0067] Firstly, the yarn drop point deposition stage model and the yarn drop point forced deposition stage model are established according to the yarn drop point stage. The specific implementation contents are as follows:

[0068] The weaving process of yarn on a mandrel with a non-circular cross-section involves complex deposition and forced deposition phases, which are affected by many factors such as yarn tension, drop point location, yarn interaction, and mandrel cross-sectional shape. For the deposition and forced deposition phases when weaving on a mandrel with a non-circular cross-section, see Figure 3 ,in Next forcibly depositing yarns Indicates the next forced deposition of yarn, Next deposited yarn Indicates the next deposition of yarn, Deposited yarn Deposition yarn ,Foreibly depositing yarns Indicates forced deposition of yarn.

[0069] During the yarn drop deposition stage, the yarn gradually approaches the core shaft according to a predetermined path and tension, and begins to form a stacked structure on the core shaft. The yarn drop point is affected by the initial tension, the intersection position with the guide ring and the interaction between other yarns. In the embodiment, the interaction between the yarns includes but is not limited to pushing and interweaving each other. The above-mentioned actions will affect the final drop point of the yarn, making the distribution of the yarn on the core shaft more uniform or forming a specific texture. In this process, the yarn needs to adapt to the non-circular cross-section of the core shaft, so the drop point will be adjusted due to changes in the cross-sectional shape.

[0070] When the yarn landing point is in the forced deposition stage, it will be squeezed or guided by other yarns, and thus forced to change its original landing point. Forced deposition usually occurs at the intersection of yarns, areas with high yarn density, or where the cross-sectional shape of the mandrel changes suddenly. In the forced deposition stage, the interaction between yarns becomes particularly important. The yarn not only needs to adapt to the cross-sectional shape of the mandrel, but also needs to coordinate and cooperate with other yarns to ensure the stability and uniformity of the entire woven structure. On the other hand, the forced deposition stage will cause changes in yarn tension, because the yarn will be stretched or compressed when it is forced to change its path. The above-mentioned tension changes will further affect the yarn landing point and the overall performance of the woven structure.

[0071] In order to accurately predict the yarn landing point and optimize the weaving structure, it is necessary to comprehensively consider factors such as the initial tension, the intersection position with the guide ring, and the yarn interaction, and establish a corresponding mathematical model.

[0072] The above yarn drop point deposition stage model satisfies the following relationship:

[0073]

[0074] in, Represents the vector pointing to the outside of the core axis on the triangle patch where the landing point is located. express k The intersection of the yarn and the guide ring at the moment, express k The point where the water drops on the mandrel surface at the moment;

[0075] In the forced deposition stage, due to the early deposition of the yarn, the yarn no longer maintains the original tangent relationship between the expected landing point and the mandrel surface, which means that the yarn has been affected by other yarns or external factors before depositing on the mandrel surface, thus changing its expected trajectory and contact state. For a schematic diagram of the forced deposition stage, please refer to Figure 4 .

[0076] Combined with the model of the forced deposition stage of the yarn drop point in the schematic diagram information embodiment, the following relationship is satisfied:

[0077]

[0078] in, Indicates the yarn tension. express k The intersection of the forced deposition yarn and the guide ring at the moment, express k The point where the yarn is forced to settle at the moment, express k Time next n-1 The spatial position of the intersection point, express k Time next n+1 The spatial position of the intersection point, express k Time next n The spatial position of the intersection point.

[0079] Furthermore, the method of establishing the yarn drop point deposition stage model in the present embodiment is only an optional condition of the present invention. In one or some other embodiments, the yarn drop point deposition stage model can be optimized according to the actual situation and the yarn condition. Optimizing the yarn drop point deposition stage model according to the actual situation and the yarn condition can enhance the adaptability of the model and improve performance and flexibility.

[0080] Then, the rigid body dynamics model is obtained by using the above-mentioned yarn drop point deposition stage model and the yarn drop point forced deposition stage model, and its specific implementation content is as follows:

[0081] The force generated by the contact point of the yarn on the core shaft follows the direction of the yarn. The above force is then translated in the world coordinate system and finally acts on the center of mass of the core shaft as a generalized force. The rigid body dynamics formula is used in the embodiment to comprehensively describe the dynamic process of the core shaft under the action of external forces such as the yarn force and obtain the rigid body dynamics model of the generalized force, which provides a theoretical basis for understanding and optimizing the motion performance of the core shaft.

[0082] The above rigid body dynamics model satisfies the following relationship:

[0083]

[0084] in, represents the generalized force at the center of mass of the core model, Represents the diagonal matrix of the 3*3 rigid body mass, Represents the inertia matrix of a 3*3 rigid body, represents the generalized acceleration of the center of mass of the core model, represents the generalized angular acceleration of the center of mass of the core mode, represents the generalized angular velocity of the center of mass of the core mode, represents the acceleration due to gravity, The output result of the generalized analysis model of the center of mass of the mandrel is analyzed by the rigid body dynamics model of the embodiment to further determine the input force required by the robot.

[0085] The gravitational acceleration satisfies the following relationship:

[0086]

[0087] Furthermore, since a rigid body can perform complex rotational motion around any axis in space, and the velocity and acceleration describing its motion state are based on a fixed world coordinate system, it is necessary to transform and adjust the inertia matrix in real time to ensure the accuracy of dynamic calculations, where the matrix transformation satisfies the following relationship:

[0088]

[0089] in, Indicates that the origin is the center of mass at time k, Represents the rotation transformation matrix from the core axis posture to the initial posture at time k, represents the inertia matrix of the rigid body in its initial state, Indicates time.

[0090] In the embodiment, real-time updating of the inertia matrix can ensure that the dynamic model is consistent with the actual motion state of the rigid body, reduce the calculation error caused by model mismatch, thereby improving the accuracy of dynamic calculation, and enhancing the stability of a core mold posture control method that adapts to the time-varying load of weaving.

[0091] Furthermore, in the present embodiment, the method for constructing the generalized force rigid body dynamics model is only an optional condition of the present invention. In one or some other embodiments, the method for constructing the rigid body dynamics model can be optimized according to the matrix establishment situation and the dynamic basis. Different application scenarios and actual needs have different model requirements. Optimizing the model according to the matrix establishment situation and the dynamic basis can ensure that the model can better adapt to various complex physical environments and dynamic requirements, thereby improving the adaptability and practicality of the model.

[0092] S4. Construct a dual-robot co-supporting core model, and obtain the generalized force at the core center of mass based on the input force required by the robot and the dual-robot co-supporting core model. The specific implementation steps and related contents are as follows:

[0093] A dual-robot co-holding core mold model is established based on the core shaft end face coordinate system. In the embodiment, the dual robots include a master robot and a slave robot, and the specific implementation content is as follows:

[0094] In order to achieve stable holding of the core mold by the dual robots, a common holding core mold model is constructed in the embodiment, and the operability model of the dual robots in the weaving process is obtained based on the above model to ensure the coordination and operational efficiency of the robot system, wherein the operability provides a quantitative indicator for the efficiency of speed and force transmission between the robot joints and the end effector, which helps to analyze and optimize the robot's motion and force control performance, and is of great significance for ensuring that the robot performs its tasks efficiently and stably.

[0095] In this embodiment, the starting point of the linear guide rail of the master robot is set as the origin of the world coordinate system, the positive z-axis is vertically upward, and the x-axis is pointing to the braiding machine along the guide rail. At the same time, the origin of the coordinate system of the end effector of the master robot is set at the center of mass of the mandrel; the slave robot uses the same world coordinate system, and the origin of the coordinate system of its end effector is consistent with that of the master robot, but its z-axis direction is opposite to that of the master robot. For details, please refer to Figure 5 .

[0096] Combined with the coordinate system construction, the coordinate transformation matrices of the master robot and the slave robot from the world coordinate system to their end effector coordinate systems are set respectively. The above matrices can describe the mapping of points in the world coordinate system to the coordinate systems of their respective end effectors.

[0097] The above two robots jointly support the core model, satisfying the following relationship:

[0098]

[0099] in, Represents the rotation matrix from the world coordinate system to the end of the robot, Represents the rotation matrix from the world coordinate system to the origin of the linear guide, Represents the rotation matrix from the origin of the linear guide to the robot base, represents the moving distance of the linear guides of the two robots, represents the robot's joint motion angle, Represents the rotation matrix from the robot base to the robot end.

[0100] The relative position relationship between the two robot ends is limited based on the model of the forced deposition stage of the yarn landing point, which can ensure that the two robot ends have the same motion trajectory in the world coordinate system. The above-mentioned synchronous motion can ensure that the core shaft, as a rigid body, can maintain its integrity when supported by the two robots, thereby effectively avoiding the occurrence of adverse phenomena such as breakage.

[0101] The above-mentioned limited behaviors in the embodiment satisfy the following relationship:

[0102] in, represents the velocity Jacobian matrix of the master robot, represents the velocity Jacobian matrix of the slave robot, represents the angular velocity Jacobian matrix of the main robot, represents the Jacobian matrix of the robot's angular velocity, represents the speed of the linear guide and the main robot joints, Represents the velocity of the linear guide and slave robot joints.

[0103] The generalized force at the center of mass of the core model is obtained based on the input force required by the robot and the dual robots jointly supporting the core model. The specific implementation content is as follows:

[0104] By calculating and analyzing the operability, the robot's joint speed and terminal force transmission performance in different postures can be accurately evaluated, providing a scientific basis for robot design and control. Represents the speed of the linear guide and robot joints and satisfies the following relationship:

[0105]

[0106] In an optional embodiment, the robot system can be regarded as a mechanical energy conversion system from the joint space to the operation space. In the above-mentioned collaborative system, the dual robots convert energy into force and motion in the operation space through the precise movement of their joints. Maneuverability is an important indicator to measure the conversion efficiency, which reflects the ability of the robot to exert force and motion in different directions. For the dual robot system equipped with linear guides, since there is no relative motion between the workpiece and the robot, the movement of the system can be accurately described and controlled.

[0107] When there is no relative motion relationship between the dual robots and the workpiece, the following relationship needs to be satisfied:

[0108] in, represents the generalized velocity of the two robot terminals, represents the Jacobian matrix of the two robots, Indicates the joint speeds of the two robots.

[0109] The generalized velocities of the two robot ends are equal to the generalized velocity vector at the center of mass of the mandrel. During the collaborative operation of the two robots, the speed of the robot ends is coordinated with the speed of the center of mass of the mandrel, which ensures the consistency and stability of the operation and helps to better understand the dynamic relationship of the dual robots in collaborative operation.

[0110] Based on the required input force of the robot obtained by the rigid body dynamics model and the dual-robot joint support core model, the force transmission relationship between the dual robots and the workpiece is further analyzed. Through precise collaborative force control strategy, the force applied to the workpiece during operation is ensured to remain consistent and accurate, thereby achieving efficient and stable operation of the workpiece.

[0111] The generalized force at the center of mass of the above core model satisfies the following relationship:

[0112] in, represents the generalized force at the center of mass of the core model, represents the pseudo-inverse matrix of the Jacobian matrix of the master robot, represents the pseudo-inverse matrix of the Jacobian matrix from the robot, represents the generalized driving force of the main robot's dual-arm joints, represents the generalized driving force from the robot's dual arm joints.

[0113] Furthermore, the specific analysis method of the generalized force in the present embodiment is only an optional condition of the present invention. In one or some other embodiments, the analysis method of the generalized force can be replaced according to the robot matrix information and speed analysis, which can more accurately reflect the actual operation status of the robot system. The above matrix information contains the interaction and relationship between the components within the system, and the speed analysis reveals the dynamic characteristics of the system under different states. Comprehensive consideration of relevant information can obtain a generalized force analysis method that better meets actual needs, thereby improving the accuracy and reliability of the analysis results.

[0114] S5. Construct a robot joint velocity analytical model based on the generalized force at the center of mass of the core model, and use the robot joint velocity analytical model to optimize the robot control parameters. The specific implementation steps and related contents are as follows:

[0115] First, the generalized force at the center of mass of the core model is mapped to the operation space to obtain the generalized force operable ellipsoid. The generalized force operable ellipsoid mainly includes the force operable ellipsoid and the moment operable ellipsoid. The specific implementation content is as follows:

[0116] In an optional embodiment, the generalized force unit ellipsoid of the joint space is mapped into the operating space to characterize the ability of the robot end effector to apply forces and torques in multiple directions. The above mapping process forms an operable ellipsoid, which can intuitively reflect the robot's ability range, directionality and ability distribution of the robot in various directions when applying forces and torques. On the other hand, the above operable ellipsoid can be used to describe the force and torque application ability of the robot end effector in a specific operating space. Based on this, it not only demonstrates the ability range of the robot to apply forces in different directions, but also reveals the directionality and efficiency of the robot's torque application.

[0117] The above force-operable ellipsoid and moment-operable ellipsoid satisfy the following relationship:

[0118]

[0119] in, Indicated in Directional force maneuverability, represents the transpose of the force direction matrix, represents the velocity Jacobian matrix of the master robot, represents the velocity Jacobian matrix of the slave robot, represents the force direction matrix, Indicated in The maneuverability of the torque in the direction, represents the angular velocity Jacobian matrix of the main robot, represents the Jacobian matrix of the robot's angular velocity, A direction matrix representing the moment.

[0120] Furthermore, during the working process of the dual-arm robot, maneuverability is an important indicator for evaluating the force and torque transmission performance of the dual-arm robot in a specific direction. Directional force maneuverability and The greater the maneuverability of the torque in the direction, the greater the and In both directions, the robot's ability to transmit force and torque is stronger. At the same time, a higher operability value indicates that the robot can respond more quickly to changes in external force or torque and maintain operational stability and accuracy. The above quantitative indicators provide an important reference for the motion and force control of the dual-arm robot.

[0121] Then, the robot joint velocity analytical model is constructed by combining the manipulable ellipsoid and the torque manipulable ellipsoid. The specific implementation content is as follows:

[0122] The force and torque manipulability function is a key performance evaluation indicator for evaluating the robot's ability to apply force and torque in the operating space. The embodiment comprehensively considers the force and torque output capabilities of the robot's end effector in different directions, providing important reference information for the robot's force control and motion planning.

[0123] Based on optimizing the maneuverability of force and torque, improving the force transmission efficiency of the robot during the weaving process, reducing the joint load, and extending the service life of the robot, a joint speed and terminal speed model including zero space and limit constraints is established in this embodiment, which refers to the robot joint speed analytical model, and the general solution of the joint speed is obtained through the above model.

[0124] The robot joint velocity analytical model in the embodiment satisfies the following relationship:

[0125]

[0126] in, Indicates the speed of the linear guide and robot joints, represents a diagonal positive definite weight matrix, represents the pseudo-inverse matrix of the Jacobian matrix of a single robot, represents the robot Jacobian matrix, represents the generalized velocity of the robot end, represents the operability optimization weight, represents the identity matrix, represents the pseudo-inverse matrix of the robot Jacobian matrix, represents an arbitrary vector in the null space of the Jacobian matrix.

[0127] Under the premise of taking into account the zero space and limit constraints, the joint speed of the robot was optimized to improve the force transmission performance. The general solution of the joint speed was obtained through the robot joint speed analytical model. The analysis results of the robot joint speed analytical model were used to ensure that the robot can efficiently complete the weaving task while meeting the constraints.

[0128] Among them, the diagonal positive definite weight matrix satisfies the following relationship:

[0129]

[0130] The value of the diagonal positive definite weight matrix is ​​determined according to the current position and limit position of the joint. As the joint position changes, the elements of the weight matrix will also change accordingly to adapt to the robot's motion and force control requirements at different positions. By dynamically adjusting and optimizing the weight matrix, the robot can better adapt to different operating environments and task requirements, and improve operating efficiency and safety.

[0131] Any vector in the null space of the Jacobian matrix satisfies the following conditions:

[0132]

[0133] When the joint is close to the limit, the maneuverability optimization weight approaches 0 infinitely to reduce the joint movement of the optimized maneuverability, and adapts to different degrees of optimization by adjusting the coefficient. In an optional embodiment, when the robot joint is close to its motion limit, the maneuverability optimization weight is gradually attenuated, wherein the attenuation behavior is achieved by adjusting the coefficient, and the speed and degree of weight reduction are adjusted according to actual needs, thereby optimizing the robot's movement while ensuring safety to adapt to the optimization requirements of different weaving tasks.

[0134] The above operability optimization weights need to satisfy the following relationship:

[0135]

[0136] in, represents the operability optimization weight, Indicates the linear guide and robot joint angles, Indicates the angle of the robot's first joint, Indicates the angle of the robot's second joint, Indicates the angle of the robot's seventh joint, Indicates the robot i The angle of the joint.

[0137] A core mold posture control method adapted to the time-varying load of weaving also includes optimizing and analyzing force operability as an example, and its specific implementation content is as follows:

[0138] First, the force-operable ellipsoid and the torque-operable ellipsoid related models are differentiated with respect to time. The above processing results are as follows:

[0139]

[0140] Then, the robot joint velocity analytical model is used to transform the force-operable ellipsoid and torque-operable ellipsoid related models. The analytical transformation results are as follows:

[0141]

[0142] in, represents any vector in the null space of the Jacobian matrix of the master robot, represents the first real number greater than or equal to 0, Indicated in Directional force operability, Indicates the linear guide and robot joint angles, Indicates the angle of the robot's first joint, Indicates the angle of the robot's second joint, Indicates the angle of the robot's seventh joint, Indicates the robot i The angle of the joints, represents any vector in the null space of the robot Jacobian matrix, is the second real number greater than or equal to 0.

[0143] Based on the robot joint velocity analytical model, we know that It is a positive definite matrix. By utilizing its characteristics in the null space, the most appropriate value is assigned to the robot joint motion according to the final analytical transformation result. Based on this, the force operability can be effectively increased, the force transmission ability of the robot in a specific direction can be improved, and the motion characteristics of the robot can be significantly improved.

[0144] Furthermore, in this embodiment, an optimization framework is designed for arbitrary-shaped mandrels. This framework comprehensively considers the interaction between yarns and the maneuverability of the robot, and provides a systematic method for optimizing robot control parameters. The robot control optimization framework based on yarn interaction, operation yarn interaction and maneuverability drive can be found in Figure 6 The control parameter optimization process based on yarn dynamics and robot maneuverability provides an effective control parameter optimization strategy for robot operation of mandrels of arbitrary shapes, which is beneficial to the practical utilization value and practical feasibility of the mandrel posture control method of the present invention that adapts to the time-varying load of weaving.

[0145] See also Figure 7 In an optional embodiment, in order to efficiently execute the core mold posture control method adapted to the time-varying load of weaving provided by the present invention, the present invention also provides a core mold posture control system adapted to the time-varying load of weaving, the core mold posture control system adapted to the time-varying load of weaving includes a processor, an input device, an output device and a memory, the processor, input device, output device and memory are interconnected, wherein the memory is used to store a computer program, the computer program includes program instructions, the processor is configured to call the program instructions, and execute the specific steps of the core mold posture control method adapted to the time-varying load of weaving and related embodiments provided by the present invention. The core mold posture control system adapted to the time-varying load of weaving of the present invention is complete in structure and objectively stable.

[0146] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention.

Claims

1. A core mold posture control method adapted to time-varying loads during weaving, characterized in that: The steps include: The core shaft end face coordinate system is established based on the main robot, and the coordinate system geometric relationship is obtained by combining the core shaft end face coordinate system: A generalized analysis model of the center of mass of the mandrel is established according to the relative motion relationship of weaving, the coordinate system of the end face of the mandrel and the geometric relationship of the coordinate system; A rigid body dynamics model is obtained by combining the mandrel center of mass generalized analysis model and the yarn drop point stage, and the mandrel center of mass generalized analysis results are analyzed by the rigid body dynamics model to determine the input force required by the robot; A dual-robot co-supporting core model is constructed, and the generalized force at the center of mass of the core model is obtained according to the input force required by the robots and the dual-robot co-supporting core model; A robot joint velocity analytical model is constructed according to the generalized force at the center of mass of the core model, and the robot control parameters are optimized using the robot joint velocity analytical model.

2. A core mold posture control method adapted to time-varying loads during weaving according to claim 1, characterized in that: The method of establishing a mandrel end face coordinate system based on the main robot and obtaining a coordinate system geometric relationship in combination with the mandrel end face coordinate system comprises: Establishing a mandrel end face coordinate system, wherein the mandrel end face coordinate system includes a world coordinate system, a mandrel centroid local coordinate system, and a guide ring coordinate system; Analyzing the geometric relationship of coordinate systems according to the world coordinate system, the local coordinate system of the center of mass of the mandrel and the guide ring coordinate system; The geometric relationship of the coordinate system satisfies the following relationship: ， in, Indicates the spatial position of the origin of the guide ring coordinate system in the world coordinate system. express t The spatial position of the origin of the center of mass coordinate system of the mandrel in the world coordinate system at the moment, Indicates the coordinate system of the center of mass of the mandrel j The location information corresponding to each trajectory point, express t The pulling speed of the core mold at this moment, Indicates the pulling time of the core mold.

3. A core mold posture control method adapted to time-varying loads during weaving according to claim 1, characterized in that: The establishment of a generalized analysis model of the center of mass of the mandrel according to the relative motion relationship of braiding, the mandrel end face coordinate system and the geometric relationship of the coordinate system comprises: A generalized analysis model of the center of mass of the mandrel is established according to the relative motion relationship of weaving, the coordinate system of the end face of the mandrel and the geometric relationship of the coordinate system; Based on the mandrel centroid generalized analysis model, a mandrel centroid generalized analysis result is obtained; The generalized analysis model of the mandrel centroid satisfies the following relationship: ， in, represents the generalized linear velocity of the core mode centroid position, represents the relative angular velocity of the guide ring in the coordinates of the center of mass of the core model, Represents the position vector of the midpoint of the guide ring in the center-of-mass coordinate system of the core mold, It represents the relative linear velocity of the guide ring under the coordinates of the center of mass of the core mold, represents the relative acceleration of the guide ring in the coordinates of the center of mass of the core model, Indicates the core mold movement time, represents the generalized angular velocity of the center of mass of the core mode, represents the generalized acceleration of the center of mass of the core model, represents the relative angular acceleration of the guide ring in the coordinates of the center of mass of the core model, Indicates the changing speed of the position of the midpoint of the guide ring in the center-of-mass coordinate system of the core mold, represents the generalized angular acceleration of the center of mass of the core mode.

4. A core mold posture control method adapted to time-varying loads during weaving according to claim 1, characterized in that: The rigid body dynamics model obtained by combining the mandrel center of mass generalized analysis model and the yarn drop point stage includes: Establishing a yarn landing point deposition stage model and a yarn landing point forced deposition stage model according to the yarn landing point stage; The yarn drop point deposition stage model satisfies the following relationship: ， in, Represents the vector pointing to the outside of the core axis on the triangle patch where the landing point is located. express k The intersection of the yarn and the guide ring at the moment, express k The point where the water drops on the mandrel surface at the moment; The yarn drop point forced deposition stage model satisfies the following relationship: ， in, Indicates the yarn tension. express k The intersection of the forced deposition yarn and the guide ring at the moment, express k The point where the yarn is forced to settle at the moment, express k Time next n-1 The spatial position of the intersection point, express k Time next n+1 The spatial position of the intersection point, express k Time next n The spatial position of the intersection point.

5. A core mold posture control method adapted to time-varying loads during weaving according to claim 1, characterized in that: The rigid body dynamics model obtained by combining the mandrel center of mass generalized analysis model and the yarn drop point stage includes: Obtaining a rigid body dynamics model using the yarn drop point deposition stage model and the yarn drop point forced deposition stage model; The rigid body dynamics model satisfies the following relationship: ， in, represents the generalized force at the center of mass of the core model, Represents the diagonal matrix of the 3*3 rigid body mass, Represents the inertia matrix of a 3*3 rigid body, represents the generalized acceleration of the center of mass of the core model, represents the generalized angular acceleration of the center of mass of the core mode, represents the generalized angular velocity of the center of mass of the core mode, represents the acceleration due to gravity, It represents the resultant force of all yarns acting on the mandrel.

6. A core mold posture control method adapted to time-varying loads during weaving according to claim 1, characterized in that: The dual-robot co-supporting core model is constructed to satisfy the following relationship: A dual-robot co-holding core mold model is established based on the core shaft end face coordinate system, wherein the dual robots include a master robot and a slave robot; The dual robots jointly support the core model, satisfying the following relationship: ， in, Represents the rotation matrix from the world coordinate system to the end of the robot, Represents the rotation matrix from the world coordinate system to the origin of the linear guide, Represents the rotation matrix from the origin of the linear guide to the robot base, represents the moving distance of the linear guides of the two robots, represents the robot's joint motion angle, Represents the rotation matrix from the robot base to the robot end.

7. A core mold posture control method adapted to time-varying loads during weaving according to claim 1, characterized in that: The generalized force at the center of mass of the core model obtained based on the input force required by the robot and the core model jointly supported by the two robots includes: The generalized force at the center of mass of the core model satisfies the following relationship: ， in, represents the generalized force at the center of mass of the core model, represents the pseudo-inverse matrix of the Jacobian matrix of the master robot, represents the pseudo-inverse matrix of the Jacobian matrix from the robot, represents the generalized driving force of the main robot's dual-arm joints, represents the generalized driving force from the robot's dual arm joints.

8. A core mold posture control method adapted to time-varying loads during weaving according to claim 7, characterized in that: The constructing of the robot joint velocity analytical model based on the generalized force at the center of mass of the core model comprises: Mapping the generalized force at the center of mass of the core module to the operation space to obtain a force generalized force operable ellipsoid, wherein the force generalized force operable ellipsoid includes a force operable ellipsoid and a moment operable ellipsoid; The robot joint velocity analytical model is constructed by combining the operable ellipsoid and the torque operable ellipsoid.

9. A core mold posture control method adapted to time-varying loads during weaving according to claim 8, characterized in that: The robot joint velocity analytical model is constructed to satisfy the following relationship: ， in, Indicates the speed of the linear guide and robot joints, represents a diagonal positive definite weight matrix, represents the pseudo-inverse matrix of the Jacobian matrix of a single robot, represents the robot Jacobian matrix, represents the generalized velocity of the robot end, represents the operability optimization weight, represents the identity matrix, represents the pseudo-inverse matrix of the robot Jacobian matrix, represents an arbitrary vector in the null space of the Jacobian matrix.

10. A core mold attitude control system adapted to time-varying loads during weaving, characterized in that: The system includes a processor, an input device, an output device and a memory, wherein the processor, the input device, the output device and the memory are interconnected, wherein the memory is used to store a computer program, the computer program includes program instructions, and the processor is configured to call the program instructions to execute a core mold posture control method that adapts to the time-varying load of weaving as described in any one of claims 1-9.

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