Three-dimensional non-planar superconducting coil automatic winding system and control method

Abstract

The three-dimensional non-planar superconducting coil automatic winding system is characterized by comprising a superconducting tape pay-off unit, a superconducting tape take-up unit, a superconducting winding cooperative controller and a simulation unit, the invention further provides a control method, constant line speed and constant tension are determined through a superconducting strip winding algorithm, and a path point set is generated through mechanical arm simulation. And a kinematics mapping model of the path points and the mechanical arm joint angle is established, and the conversion relation between the linear speed and the joint angular speed is deduced. And the cooperative controller corrects the joint angular velocity based on a strip thickness compensation algorithm, integrates real-time linear velocity feedback of the meter counting mechanism and dynamically adjusts joint motion parameters. The tension control mechanism synchronously collects actual tension data, and the torque value of the pay-off mechanism is calculated through a constant tension algorithm. And finally, the compensated joint angular velocity and the real-time paying-off torque are synchronously output to a mechanical arm and a paying-off device, and closed-loop control is formed. According to the invention, the technical problems of high coil geometric complexity and poor process consistency in star simulator manufacturing are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of superconducting applications, and in particular to an automatic winding system and a control method for a superconducting coil. Background Art

[0002] Nuclear fusion energy is considered as one of the ideal solutions to solve the global energy problem because of its clean, efficient and sustainable characteristics. Among them, magnetic confinement nuclear fusion is one of the main research directions for realizing the utilization of nuclear fusion energy. In the magnetic confinement system, a special magnetic field configuration needs to be constructed to confine the high-temperature plasma so that it can reach the conditions required for nuclear fusion reaction. Stellarator is one of the systems that can generate complex and precise magnetic field configurations. Compared with tokamaks, stellarator has some unique advantages, such as its more stable magnetic field structure and easier control of plasma boundary conditions, which makes it have important research value and application prospects in the field of nuclear fusion research. The magnetic field of the stellarator is completely generated by an external three-dimensional non-planar superconducting coil system, which leads to many technical difficulties in the manufacture of stellarator. For example, in the winding process of the three-dimensional non-planar superconducting coil, a high-degree-of-freedom and high-precision winding machine is required to ensure the number of turns, shape and size accuracy of the coil. In addition, the winding tension has an important influence on the quality and performance of the coil. Excessive tension may cause the superconducting tape to stretch, deform or break, while too little tension may make the coil loose and not tight. However, the existing winding can only realize the automated winding of planar superconducting coils, but cannot realize the automated winding of non-planar superconducting coils, and cannot meet the needs of large-scale production.

[0003] The invention patent with application number 202410829876.0 discloses a device, system and method for winding a multi-wire superconducting double-pancake coil in parallel, including multiple pay-off units and a take-up unit. Multi-wire synchronous winding is achieved through bus control, and the functions of wire division and rewinding are supported to improve the yield rate. This technology gathers multiple superconducting tapes through a winding mechanism, which is suitable for the efficient winding of planar double-pancake coils, especially for scenarios where multi-wire winding is required in magnetic confinement fusion devices. Its advantages lie in modular design, tension control and line speed adjustment, but it is limited to the winding of planar coils. It is impossible to achieve precise control of the three-dimensional trajectory using a fixed take-up unit and a linearly laid pay-off unit. Summary of the invention

[0004] Aiming at the technical problem that the existing devices cannot achieve the high-degree-of-freedom and high-precision automated winding of the stellarator's three-dimensional non-planar superconducting coils, the present invention proposes a three-dimensional non-planar superconducting coil automated winding system and control method. Through the superconducting tape unwinding unit, superconducting tape rewinding unit, and superconducting winding collaborative controller, it can achieve the automated winding of three-dimensional non-planar superconducting coils, effectively improving the production efficiency of three-dimensional non-planar superconducting coils, solving the technical problems of high coil geometric complexity and poor process consistency in stellarator manufacturing, and providing key technical support for the large-scale engineering manufacturing of stellarator devices.

[0005] In order to achieve the above object, the technical solution of the present invention is realized as follows:

[0006] A three-dimensional non-planar superconducting coil automated winding system includes a superconducting tape unwinding unit, a superconducting tape rewinding unit, a superconducting winding collaborative controller, and a simulation unit; the simulation unit is connected to the superconducting winding collaborative controller; the superconducting tape rewinding unit includes a superconducting coil skeleton and a multi-axis robotic arm. The multi-axis robotic arm includes a multi-axis robotic arm controller and a multi-axis robotic arm actuator connected to each other. The multi-axis robotic arm controller is connected to the superconducting winding collaborative controller, and the end joint of the multi-axis robotic arm actuator is rigidly connected to the superconducting coil skeleton; the superconducting tape unwinding unit includes a guiding mechanism. The guiding mechanism assists the superconducting tape to always pass through the fixed point O2 through a guiding wheel and keeps the movement direction of the superconducting tape unchanged; the end joint, as a moving point, drives the superconducting coil skeleton to rotate while making adjustments in three directions, and the moving trajectory of the superconducting coil skeleton always passes through the fixed point O2.

[0007] Preferably, the superconducting tape unwinding unit further includes an unwinding mechanism, a tension control mechanism, and a length measuring mechanism. The unwinding mechanism, the tension control mechanism, and the length measuring mechanism are all connected to the superconducting winding collaborative controller; the superconducting coil skeleton is a three-dimensional non-planar superconducting coil skeleton or a planar superconducting coil skeleton. The fixed point O2 is the origin of the second coordinate system. The guiding mechanism assists the superconducting tape to always pass through the origin O2 of the second coordinate system and keeps the movement direction of the superconducting tape consistent with the horizontal axis direction of the second coordinate system.

[0008] Preferably, the superconducting winding collaborative controller includes a superconducting tape winding process algorithm module, a constant tension control algorithm module, a superconducting tape thickness compensation algorithm module, and a constant linear velocity control algorithm module;

[0009] The superconducting tape winding process algorithm module is used to output a constant tension F and a constant linear velocity V according to the winding parameters and process requirements of the superconducting tape. The superconducting tape winding process algorithm module is communicatively connected to the simulation unit;

[0010] The constant tension control algorithm module is used to calculate the wire release torque of the wire release mechanism in real time, and the constant tension control algorithm module is communicatively connected to the tension control mechanism and the wire release mechanism respectively;

[0011] The superconducting tape thickness compensation algorithm module is used to compensate the joint angular velocity of the multi-axis robotic arm according to the number of winding turns, and the superconducting tape thickness compensation algorithm module is communicatively connected to the multi-axis robotic arm controller;

[0012] The constant linear velocity control algorithm module is used to adjust the magnitude of the angular velocity of each joint of the multi-axis robotic arm in real time, and the constant linear velocity control algorithm module is communicatively connected to the length measuring mechanism and the multi-axis robotic arm controller respectively.

[0013] A control method for a three-dimensional non-planar superconducting coil automatic winding system, comprising the steps:

[0014] S1: Obtain the constant linear velocity V and the constant tension F to be maintained during winding based on the superconducting tape winding process algorithm, and obtain the set of winding path points P based on the simulation software of the multi-axis robotic arm;

[0015] S2: Perform forward kinematics modeling based on the set of winding path points to determine the mapping relationship between the set of winding path points and the joint angles of the multi-axis robotic arm, and determine the mapping between the constant linear velocity V and the joint angular velocity through the simulation software of the multi-axis robotic arm according to the obtained joint angles;

[0016] S3: Based on the mapping between the constant linear velocity V and the joint angular velocity, the superconducting winding cooperative controller compensates the joint angular velocity according to the superconducting tape thickness compensation algorithm;

[0017] S4: Use the length measuring mechanism to obtain the actual linear velocity in real time and feedback it to the superconducting winding cooperative controller. The superconducting winding cooperative controller combines the compensated joint angular velocity and uses the constant linear velocity control algorithm to dynamically adjust the joint angular velocity to obtain the angular velocity executed by the multi-axis robotic arm;

[0018] S5: Use the tension control mechanism to obtain the actual tension magnitude in real time and feedback it to the superconducting winding cooperative controller. The superconducting winding cooperative controller calculates the real-time wire release torque through the constant tension algorithm;

[0019] S6: Synchronously send the final joint angular velocity and the final wire release torque to the multi-axis robotic arm and the wire release mechanism, and loop through steps S3 - S6 until the winding task is completed to ensure the dynamic balance of the constant linear velocity and the constant tension.

[0020] Furthermore, the specific steps of step S1 are:

[0021] S1.1: Input the parameters and process requirements of the superconducting tape into the superconducting winding cooperative controller; obtain the magnitudes of the constant linear velocity V and the constant tension F to be maintained during winding according to the superconducting tape winding process algorithm;

[0022] S1.2: Construct a 3D model of the superconducting coil skeleton and import it into the simulation software of the multi-axis robotic arm. Use the simulation software of the multi-axis robotic arm to generate a set of winding path points P = {P1, P2, …, P N}, that is, the motion trajectory of the end joint of the multi-axis robotic arm.

[0023] Furthermore, the mapping relationship between the set of winding path points P and the joint angles of the multi-axis robotic arm is:

[0024]

[0025] where P ∈ R 3 , and satisfies the constraint condition represents a trajectory-constant line passing through the origin O2 of the second coordinate system, θ i is the i-th joint angle of the multi-axis robotic arm, f kin (·) is the forward kinematics function;

[0026] The mapping of the constant linear velocity V and the joint angular velocity determined by the simulation software of the multi-axis robotic arm is:

[0027]

[0028] where represents the pseudo-inverse of the Jacobian matrix, θ = [θ1, θ2, θ3, …, θ k T , represents the angle of each joint of the multi-axis robotic arm, represents the joint angular velocity of each joint of the multi-axis robotic arm, w k is the k-th joint angular velocity.

[0029] The calculation process of the superconducting tape thickness compensation algorithm is as follows: When winding the n-th turn of the superconducting tape, according to the thickness d of the superconducting tape, compensate the set of winding path points P in the Y2-axis direction, and calculate the compensation amount ΔY n ; Calculate the compensated path point set according to the compensation amount in the Y2-axis direction; Update the Jacobian matrix based on the compensated path point set and adjust the joint angular velocity to obtain the compensated joint angular velocity

[0030] The calculation process of the constant linear velocity control algorithm is as follows: Calculate the velocity error e(t) according to the actual linear velocity; Calculate the compensation amount according to the velocity error According to the compensation amount Calculate the joint angular velocity correction amount through the PID algorithm According to the joint angular velocity correction amount and the compensated joint angular velocity Calculate the execution joint angular velocity w(t) of the multi-axis robotic arm.​

[0031] The compensation amount ΔY n The calculation formula is as follows:

[0032]

[0033] Wherein, represents the unit vector in the Y2-axis direction;

[0034] The formula for calculating the compensated path point set is:

[0035]

[0036] Wherein, P' n is the compensated path point set, and θ' i,n is the i-th joint angle after the n-th circle of compensation;

[0037] The formula for obtaining the compensated joint angular velocity is as follows:

[0038]

[0039] Wherein, represents the compensated joint angular velocities, θ' n represents the compensated joint angle calculated according to the mapping relationship between the winding path point set P and the respective joint angles of the multi-axis robotic arm, and θ' n =[θ' 1,n ,θ' 2,n ,θ' 3,n ,…,θ' k,n T , is the path gradient, is the compensated path gradient.

[0040] Furthermore, the formula for calculating the compensation amount according to the velocity error is:

[0041]

[0042] The formula for calculating the joint angular velocity correction amount by the PID algorithm according to the compensation amount is as follows:

[0043]

[0044] Wherein, K p is the proportional gain, K i is the integral gain, and K d is the derivative gain; ​

[0045] The aforementioned correction amount based on joint angular velocity and the compensated joint angular velocity The formula for calculating the execution joint angular velocity w(t) of a multi-axis robotic arm is as follows:

[0046]

[0047] wherein, represents the corresponding compensated joint angular velocity at time t.

[0048] The calculation process of the aforementioned constant tension algorithm is as follows: Calculate the tension error Fe(t) based on the actual tension magnitude:

[0049] Fe(t) = F - F a (t)

[0050] Calculate the real-time wire pay-off torque N(t) based on the tension error Fe(t):

[0051]

[0052] wherein, K is the control gain coefficient, and T i is the integral time constant.

[0053] The beneficial effects of the present invention are as follows:

[0054] The present invention integrates the motion control of a multi-axis robotic arm, the constant tension and constant linear velocity algorithms, and the thickness compensation algorithm through a superconducting winding collaborative controller to achieve high-precision automatic winding of a three-dimensional non-planar superconducting coil; the multi-axis robotic arm combines with a simulation unit to generate complex trajectories to ensure the accurate movement of the end effector along a preset path; the constant tension and constant linear velocity double closed-loop control technology effectively avoids the stretching or loosening of the strip and ensures the structural stability of the coil; the dynamic thickness compensation algorithm automatically corrects the cumulative error in multi-layer winding and improves the geometric consistency between turns; the system is compatible with various robotic arm models and coil skeleton topological structures, adapts to complex application scenarios such as stellarators, and significantly improves production efficiency and engineering feasibility. It solves the technical problems of high coil geometric complexity and poor process consistency in stellarator manufacturing. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following-described drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0056] Figure 1 It is a schematic diagram of the overall structure of the three-dimensional non-planar superconducting coil automatic winding system of the present invention.

[0057] Figure 2 This is a schematic diagram of the wire-reeling unit structure of the superconducting tape of the present invention.

[0058] Figure 3 This is a schematic diagram of the principle of the control method of the present invention.

[0059] Figure 4 This is a schematic diagram of the three-dimensional non-planar superconducting double-pancake coil skeleton of the present invention. Detailed implementation manners

[0060] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0061] Embodiment 1

[0062] A three-dimensional non-planar superconducting coil automatic winding system, as Figure 1 shown, includes a superconducting tape pay-off unit, a superconducting tape wire-reeling unit, a superconducting winding collaborative controller, and a simulation unit. The superconducting tape pay-off unit, the superconducting tape wire-reeling unit, and the simulation unit are all connected to the superconducting winding collaborative controller; the superconducting winding collaborative controller controls the pay-off operation of the superconducting tape pay-off unit and the wire-reeling operation of the superconducting tape wire-reeling unit to jointly complete the automatic winding of the superconducting coil.

[0063] The described superconducting tape pay-off unit includes a pay-off mechanism, a tension control mechanism, a length measuring mechanism, and a guiding mechanism; the pay-off mechanism, the tension control mechanism, and the length measuring mechanism are all connected to the superconducting winding collaborative controller.

[0064] The pay-off mechanism uses a servo motor to drive the pay-off reel, which is used to change the tension on the superconducting tape by adjusting the torque size, so as to control the pay-off tension to maintain a constant tension; ensure that the superconducting tape always maintains a constant tension during the winding process, and avoid the tape being stretched or broken due to excessive tension, or the coil being loose due to too small tension.

[0065] The tension control mechanism is used to collect the tension on the superconducting tape in real time and feedback to control the torque size of the pay-off mechanism; quickly respond to external disturbances (such as friction or inertia changes) to ensure tension stability.

[0066] The length measuring mechanism records the length of the superconducting tape based on an optical encoder, calculates the linear velocity of the superconducting tape in real time, and is used to feedback and control the rotational speed and moving speed of the three-dimensional non-planar coil skeleton to maintain a constant linear velocity of the superconducting tape. Combined with the movement adjustment of the robotic arm, the constancy of the linear velocity is achieved, and the problem of uneven inter-turn gaps caused by speed fluctuations is avoided.

[0067] The guiding mechanism uses guide wheels to assist the superconducting tape to always pass through the origin O2 of the second coordinate system and keep the moving direction of the superconducting tape coincident with the direction of the X2 axis. The origin O2 of the second coordinate system (O2-X2Y2Z2) is a combined point of the wire winding and unwinding units in space, and this point can be artificially defined at a suitable place. The X2 axis is consistent with the moving direction of the superconducting tape, the Y2 axis is perpendicular to the moving direction of the tape, and the Z2 axis is determined by the right-hand rule. The guiding mechanism eliminates the position offset during the winding process and provides a stable input reference of the superconducting tape for the multi-axis robotic arm.

[0068] Specifically, the superconducting tape winding unit includes a superconducting coil skeleton and a multi-axis robotic arm. In this embodiment, a 6-axis robotic arm is used. The superconducting coil skeleton is used to provide a support structure that meets the process requirements for the superconducting tape to ensure that the winding shape is consistent with the design model. The superconducting coil skeleton is a three-dimensional non-planar superconducting coil skeleton or a planar superconducting coil skeleton, made of resin material, and supports a three-dimensional non-planar topological structure, such as Figure 4 shown, a stellarator spiral shape, that is, a three-dimensional non-planar superconducting coil skeleton; or a conventional ring shape, that is, a planar superconducting coil. The multi-axis robotic arm is used to wind the three-dimensional non-planar superconducting coil according to the execution joint angular velocity output by the superconducting winding co-controller, and achieve precise winding of complex three-dimensional non-planar trajectories through high-degree-of-freedom movement.

[0069] The multi-axis robotic arm includes a multi-axis robotic arm controller and a multi-axis robotic arm actuator connected to each other. The multi-axis robotic arm controller is connected to the superconducting winding co-controller. The end joint of the multi-axis robotic arm actuator is rigidly connected to the superconducting coil skeleton. In this embodiment, the end joint of the multi-axis robotic arm actuator has an output shaft, such as Figure 4 shown, the superconducting coil skeleton is fixedly connected to the connecting shaft through multiple rigid connectors (only two are drawn in the figure), such as welding, bolt connection, and key connection. The connecting shaft is connected to the output shaft of the end joint through a rigid coupling to ensure that there is no relative sliding between the superconducting coil skeleton and the end joint of the multi-axis robotic arm.

[0070] The end joint is located at the origin O1 of the first coordinate system, and the end joint has the characteristic of infinite rotation centered on the Z1 axis of the first coordinate system (counterclockwise rotation in the figure), and can move the superconducting coil skeleton along the X2 axis, Y2 axis, and Z2 axis directions. That is, the end joint, as a moving point, drives the superconducting coil skeleton to perform rotational motion while making adjustments in the three directions of X2, Y2, and Z2. The moving trajectories of the three-dimensional non-planar superconducting coil skeleton all pass through the origin O2 of the second coordinate system at a constant linear velocity and are tangent to the X2 axis direction. The first coordinate system (O1-X1Y1Z1) has the rotation center of the end joint as the origin O1, the Z axis coincides with the rotation axis of the end joint, and the X1 axis points to the initial motion direction of the superconducting coil skeleton.

[0071] Specifically, the simulation unit is a multi-axis robotic arm simulation software, which is used to generate the joint angular velocity of the multi-axis robotic arm under ideal conditions according to the constant linear velocity V and the superconducting coil skeleton And combined with the forward kinematics model to solve the joint angle mapping relationship and optimize the robotic arm motion trajectory; through the linkage of the simulation results and the cooperative controller, high-precision planning of complex paths is realized, and the linear velocity fluctuation caused by the change of path curvature is avoided.

[0072] Specifically, the superconducting winding cooperative controller includes a superconducting tape winding process algorithm module, a constant tension control algorithm module, a superconducting tape thickness compensation algorithm module, and a constant linear velocity control algorithm module.

[0073] The superconducting tape winding process algorithm module consists of a winding process expert system, which is used to output the magnitudes of a constant tension F and a constant linear velocity V suitable for the process according to the winding parameters and process of the superconducting tape, so as to ensure that the superconducting tape will not be damaged during the winding process. The superconducting tape winding process algorithm module is communicatively connected to the simulation unit.

[0074] The constant tension control algorithm module is used to calculate the pay-off torque of the pay-off mechanism in real time. The constant tension control algorithm module is communicatively connected to the tension control mechanism and the pay-off mechanism respectively.

[0075] The superconducting tape thickness compensation algorithm module is used to compensate the joint angular velocity of the multi-axis robotic arm according to the number of winding turns to achieve the control of the constant linear velocity. The superconducting tape thickness compensation algorithm module is communicatively connected to the multi-axis robotic arm controller, and the number of winding turns is fed back by the multi-axis robotic arm controller.

[0076] The constant linear velocity control algorithm module is used to calculate according to the constant linear velocity V, the compensation value of the multi-axis robotic arm joint angular velocity and the linear velocity V collected in real time by the superconducting tape pay-off unit aPerform comprehensive calculations and adjust the angular velocity magnitude w(t) of each joint of the multi-axis robotic arm in real time to achieve the constant linear velocity winding of the superconducting tape. The constant linear velocity control algorithm module is respectively communicatively connected to the length measuring mechanism and the multi-axis robotic arm controller.

[0077] Taking the winding of a three-dimensional non-planar superconducting single-wire double-pancake coil as an example, the process is as follows:

[0078] 1. Input the length, width, and thickness of the superconducting tape and the winding method of single-wire double-pancake into the superconducting winding collaborative controller. The superconducting winding collaborative controller obtains the constant linear velocity V and the constant tension F required for winding.

[0079] 2. The three-dimensional models of the superconducting coil skeletons 1 and 2 are the same. Therefore, import the superconducting coil skeleton 1 into the simulation software of the multi-axis robotic arm, and use the simulation software of the multi-axis robotic arm to generate the motion trajectories of the end joints of the multi-axis robotic arm.

[0080] 3. Determine the mapping relationship between the constant linear velocity V of the superconducting coil skeleton 1 and the joint angular velocity through the simulation software of the multi-axis robotic arm.

[0081] 4. Place the superconducting tape reel A on the unwinding mechanism.

[0082] 5. Conduct tape running. The superconducting tape passes through the tension control mechanism, the length measuring mechanism, and the guiding mechanism in sequence, and is finally taken up by the three-dimensional non-planar superconducting coil skeleton 1.

[0083] 6. Start winding. Wind half of the superconducting tape of the superconducting tape reel A onto the three-dimensional non-planar superconducting coil skeleton 1. During the winding process, according to the constant tension algorithm, the constant linear velocity algorithm, and the thickness compensation algorithm of the superconducting winding collaborative controller, wind with a constant tension F and a constant linear velocity V of the tape.

[0084] 7. Wind the remaining half of the superconducting tape of the superconducting tape reel A onto the superconducting coil skeleton 2. Before winding, interchange the positions of the three-dimensional non-planar superconducting coil skeleton 1 and the three-dimensional non-planar superconducting coil skeleton 2. Continue winding in the manner of step 6 until the winding is completed.

[0085] Embodiment 2

[0086] A control method for a three-dimensional non-planar superconducting coil automatic winding system includes the steps:

[0087] S1: Obtain the constant linear velocity V and the constant tension F to be maintained during winding based on the superconducting tape winding process algorithm, and obtain the set of winding path points based on the simulation software of the multi-axis robotic arm.

[0088] Specifically:

[0089] S1.1: Input the parameters and process requirements of the superconducting tape into the superconducting winding co - controller; obtain the magnitudes of the constant linear velocity V and the constant tension F to be maintained during winding according to the superconducting tape winding process algorithm.

[0090] The parameters refer to the length, width, and thickness of the superconducting tape. In this embodiment, the thickness is d = 1 mm; the process requirements refer to single - wire, multi - wire, single - pancake, multi - pancake, and number of turns. It can form single - wire single - pancake, single - wire multi - pancake, multi - wire single - pancake, multi - wire multi - pancake. In this embodiment, single - wire double - pancake is adopted.

[0091] S1.2: Construct a three - dimensional model of the superconducting coil skeleton, such as a three - dimensional non - planar superconducting double - pancake coil skeleton, and import it into the simulation software of the multi - axis robotic arm. Use the simulation software of the multi - axis robotic arm to generate a set of winding path points P = {P1, P2, …, P N}, that is, the motion trajectory of the end joint of the multi - axis robotic arm.

[0092] S2: Based on the set of winding path points, perform forward kinematics modeling to determine the mapping relationship between the set of winding path points and the joint angles of the multi - axis robotic arm. According to the obtained joint angles through the simulation software of the multi - axis robotic arm, determine the mapping between the constant linear velocity V and the joint angular velocity to ensure that the end joint drives the coil skeleton to move strictly along the preset trajectory.

[0093] Specifically, the mapping relationship between the set of winding path points P and the joint angles of each joint of the multi - axis robotic arm is:

[0094]

[0095] where P ∈ R 3 and satisfies the constraint condition represents a trajectory - constant line passing through the origin O2 of the coordinate system, θ i is the i - th joint angle of the multi - axis robotic arm, and f kin (·) is the forward kinematics function.

[0096] Determine the mapping between the constant linear velocity V and the joint angular velocity through the simulation software of the multi - axis robotic arm as:

[0097]

[0098] where, represents the pseudo - inverse of the Jacobian matrix, θ = [θ1, θ2, θ3, θ4, θ5, θ6] T represents the angle of each joint of the multi - axis robotic arm, It represents the angular velocities of the joints of the multi-axis robotic arm. w1, w2, …, w6 represent the angular velocities of the 1st to 6th joints. This algorithm ensures a constant motion speed at the end joint by real-time solving the relationship between the pose and velocity of the robotic arm, avoiding the linear velocity fluctuations caused by the change of path curvature. Through high-precision path planning and kinematic solution, the system can achieve a positioning accuracy of ±0.1 mm for complex three-dimensional trajectories, meeting the strict geometric requirements of the stellarator coil.

[0099] S3: Based on the mapping between the constant linear velocity V and the joint angular velocities, the superconducting winding cooperative controller compensates the joint angular velocities according to the superconducting tape thickness compensation algorithm; during multi-layer winding, the cumulative thickness of the superconducting tape will cause misalignment between the turns of the coil; the present invention realizes automatic compensation through the following principle.

[0100] Specifically, the calculation process of the superconducting tape thickness compensation algorithm is as follows:

[0101] When winding the nth turn of the superconducting tape, according to the thickness d of the superconducting tape, the path point set P is compensated in the Y2-axis direction, and the compensation amount ΔY in the Y2-axis direction is calculated n :

[0102]

[0103] where, represents the unit vector in the Y2-axis direction.

[0104] Further, the path point set after compensation is calculated according to the compensation amount in the Y2-axis direction:

[0105]

[0106] where, P' n is the path point set after compensation, and θ' i,n is the i-th joint angle after the nth turn of compensation.

[0107] Further, the Jacobian matrix is updated based on the path point set after compensation and the joint angular velocities are adjusted to obtain the compensated joint angular velocities

[0108]

[0109] where, represents the compensated joint angular velocities, represents the angular velocities of the 1st to 6th joints after the nth turn of compensation, and θ' n represents the compensated joint angles calculated according to the mapping relationship between the path point set P of the winding and the respective joint angles of the multi-axis robotic arm, and θ' n =[θ' 1,n ,θ' 2,n ,θ' 3,n, θ' 4,n , θ' 5,n , θ' 6,n T , is the path gradient, is the path gradient after compensation. This algorithm dynamically corrects the joint angular velocity to offset the path deviation caused by thickness accumulation. The error of the coil turn - to - turn spacing after compensation is ≤ ±0.05 mm, significantly improving the geometric consistency of multi - layer winding.

[0110] S4: Use the length - measuring mechanism to obtain the actual linear velocity in real - time, and feedback it to the superconducting winding collaborative controller. The superconducting winding collaborative controller combines the compensated joint angular velocity and adopts a constant - linear - velocity control algorithm to dynamically adjust the joint angular velocity, and obtains the angular velocity executed by the multi - axis robotic arm.

[0111] Specifically, map the compensated joint angular velocity of the multi - axis robotic arm mapping relationship, and the actual linear velocity V a (t) collected by the length - measuring mechanism in real - time, and feedback it to the superconducting winding collaborative controller; the superconducting winding collaborative controller dynamically adjusts the joint angular velocity of each joint of the multi - axis robotic arm according to the constant - linear - velocity control algorithm, and feeds it back to the multi - axis robotic arm in real - time to maintain a constant linear velocity V.

[0112] The calculation process of the constant - linear - velocity control algorithm is: calculate the velocity error according to the actual linear velocity:

[0113] e(t) = V - V a (t)

[0114] where e(t) is the velocity error, and V a (t) is the actual linear velocity.

[0115] Furthermore, calculate the compensation amount according to the velocity error

[0116]

[0117] Furthermore, according to the compensation amount calculate the joint angular velocity correction amount through the PID algorithm

[0118]

[0119] where, K p is the proportional gain, taking 0.8, K i is the integral gain, taking 0.1, K d is the derivative gain, taking 0.02.

[0120] Furthermore, according to the joint angular velocity correction amount ​and the compensated joint angular velocity Calculate the execution joint angular velocity w(t) of the multi-axis robotic arm:

[0121]

[0122] wherein, represents the corresponding compensated joint angular velocity at time t, and is obtained according to the compensated joint angular velocity obtained.

[0123] S5: Use the tension control mechanism to obtain the actual tension magnitude in real time, and feedback it to the superconducting winding collaborative controller. The superconducting winding collaborative controller calculates the real-time wire release torque through a constant tension algorithm.

[0124] The calculation process of the constant tension algorithm is as follows: Calculate the tension error Fe(t) according to the actual tension magnitude:

[0125] Fe(t) = F - F a (t)

[0126] wherein, F a (t) is the actual tension magnitude.

[0127] Furthermore, calculate the real-time wire release torque N(t) according to the tension error Fe(t):

[0128]

[0129] wherein, K is the control gain coefficient, and T i is the integral time constant. This algorithm dynamically adjusts the torque of the wire release mechanism to offset the tension fluctuations caused by mechanical inertia or strip friction. Through double closed-loop control (tension and speed), the system maintains a tension fluctuation ≤ ±2% of the rated value and a linear velocity fluctuation ≤ ±1% during the winding process, effectively avoiding problems such as strip stretching or loosening.

[0130] S6: Synchronously send the final joint angular velocity and the final wire release torque to the multi-axis robotic arm and the wire release mechanism, and loop to execute steps S3 - S6 until the winding task is completed, ensuring the dynamic balance of the constant linear velocity and the constant tension.

[0131] The structural design of the system of the present invention realizes the fully automated winding of three-dimensional non-planar superconducting coils through high-precision motion control of the robotic arm, multi-closed-loop feedback system, and intelligent compensation algorithm, and solves the technical problems of high geometric complexity and poor process consistency of the coils in the stellarator manufacturing. The system meets the engineering requirements in terms of tension stability, linear velocity control, path accuracy, etc., providing reliable technical support for large-scale production.

[0132] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A three-dimensional non-planar superconducting coil automatic winding system, characterized in that, It includes a superconducting tape pay-off unit, a superconducting tape take-up unit, a superconducting winding collaborative controller, and a simulation unit; the simulation unit is connected to the superconducting winding collaborative controller; the superconducting tape take-up unit includes a superconducting coil skeleton and a multi-axis robotic arm. The multi-axis robotic arm includes a multi-axis robotic arm controller and a multi-axis robotic arm actuator connected to each other. The multi-axis robotic arm controller is connected to the superconducting winding collaborative controller. The end joint of the multi-axis robotic arm actuator is rigidly connected to the superconducting coil skeleton; the superconducting tape pay-off unit includes a guiding mechanism. The guiding mechanism uses guide wheels to assist the superconducting tape to always pass through the fixed point O2 and keep the moving direction of the superconducting tape unchanged. The end joint, as a moving point, drives the superconducting coil skeleton to rotate while making adjustments in three directions, and the moving trajectory of the superconducting coil skeleton always passes through the fixed point O2.

2. The three-dimensional non-planar superconducting coil automatic winding system according to claim 1, wherein The superconducting tape pay-off unit further includes a pay-off mechanism, a tension control mechanism, and a length measuring mechanism. The pay-off mechanism, the tension control mechanism, and the length measuring mechanism are all connected to the superconducting winding collaborative controller; the superconducting coil skeleton is a three-dimensional non-planar superconducting coil skeleton or a planar superconducting coil skeleton. The fixed point O2 is the origin of the second coordinate system. The guiding mechanism assists the superconducting tape to always pass through the origin O2 of the second coordinate system and keep the moving direction of the superconducting tape consistent with the horizontal axis direction of the second coordinate system.

3. The three-dimensional non-planar superconducting coil automatic winding system according to claim 1, characterized in that The superconducting winding collaborative controller includes a superconducting tape winding process algorithm module, a constant tension control algorithm module, a superconducting tape thickness compensation algorithm module, and a constant linear velocity control algorithm module; The superconducting tape winding process algorithm module is used to output a constant tension F and a constant linear velocity V according to the winding parameters and process requirements of the superconducting tape. The superconducting tape winding process algorithm module is communicatively connected to the simulation unit; The constant tension control algorithm module is used to calculate the pay-off torque of the pay-off mechanism in real time. The constant tension control algorithm module is communicatively connected to the tension control mechanism and the pay-off mechanism respectively; The superconducting tape thickness compensation algorithm module is used to compensate the joint angular velocity of the multi-axis robotic arm according to the number of winding turns. The superconducting tape thickness compensation algorithm module is communicatively connected to the multi-axis robotic arm controller; The constant linear velocity control algorithm module is used to adjust the angular velocity of each joint of the multi-axis robotic arm in real time. The constant linear velocity control algorithm module is communicatively connected to the length measuring mechanism and the multi-axis robotic arm controller respectively.

4. A control method for an automated winding system of a three-dimensional non-planar superconducting coil, which is used to control an automated winding system of a three-dimensional non-planar superconducting coil according to any one of claims 1 to 3, characterized in that, It includes the steps: S1: Obtain the constant linear velocity V and the constant tension F to be maintained during winding based on the superconducting tape winding process algorithm, and obtain the set of winding path points P based on the simulation software of the multi-axis robotic arm; S2: Based on the set of winding path points, perform forward kinematics modeling to determine the mapping relationship between the set of winding path points and the joint angles of the multi-axis robotic arm, and determine the mapping between the constant linear velocity V and the joint angular velocity through the simulation software of the multi-axis robotic arm according to the obtained joint angles; S3: Based on the mapping between the constant linear velocity V and the joint angular velocity, the superconducting winding collaborative controller performs joint angular velocity compensation according to the superconducting tape thickness compensation algorithm; S4: Use the linear meter mechanism to obtain the actual linear velocity in real time, and feedback it to the superconducting winding cooperative controller. The superconducting winding cooperative controller combines the compensated joint angular velocity and uses a constant linear velocity control algorithm to dynamically adjust the joint angular velocity to obtain the angular velocity executed by the multi-axis robotic arm. S5: Use the tension control mechanism to obtain the actual tension magnitude in real time, and feedback it to the superconducting winding cooperative controller. The superconducting winding cooperative controller calculates the real-time wire pay-off torque through a constant tension algorithm. S6: Synchronously send the final joint angular velocity and the final wire pay-off torque to the multi-axis robotic arm and the wire pay-off mechanism, and loop through steps S3 - S6 until the winding task is completed to ensure the dynamic balance of the constant linear velocity and the constant tension.

5. The control method of the three-dimensional non-planar superconducting coil automatic winding system according to claim 4, characterized in that, The specific steps of step S1 are as follows: S1.1: Input the parameters and process requirements of the superconducting tape into the superconducting winding cooperative controller; obtain the magnitudes of the constant linear velocity V and the constant tension F to be maintained during winding according to the superconducting tape winding process algorithm. S1.2: Build a 3D model of the superconducting coil skeleton and import it into the simulation software of the multi-axis robotic arm. Use the simulation software of the multi-axis robotic arm to generate a set of winding path points P = {P1, P2, …, P N}, which is the motion trajectory of the end joint of the multi-axis robotic arm.

6. The control method of the three-dimensional non-planar superconducting coil automatic winding system according to claim 5, characterized in that, The mapping relationship between the set of winding path points P and the respective joint angles of the multi-axis robotic arm is: where P ∈ R 3 , and satisfies the constraint condition represents a trajectory that constantly passes through the origin O2 of the second coordinate system, θ i is the i-th joint angle of the multi-axis robotic arm, f kin (·) is the forward kinematics function; The mapping between the constant linear velocity V and the joint angular velocity determined by the simulation software of the multi-axis robotic arm is: Among them, represents the pseudo-inverse of the Jacobian matrix, and θ = [θ1, θ2, θ3, …, θ k T , which represents the angle of each joint of the multi-axis robotic arm, represents the angular velocity of each joint of the multi-axis robotic arm, and w k is the angular velocity of the k-th joint.​ 7. The control method of the three-dimensional non-planar superconducting coil automatic winding system according to claim 6, characterized in that, The calculation process of the superconducting strip thickness compensation algorithm is as follows: When winding the superconducting strip for the nth turn, according to the thickness d of the superconducting strip, the winding path point set P is compensated in the Y2-axis direction, and the compensation amount ΔY in the Y2-axis direction is calculated. n The compensated path point set is calculated based on the compensation amount in the Y2-axis direction; Update the Jacobian matrix based on the compensated path point set and adjust the joint angular velocity to obtain the compensated joint angular velocity The calculation process of the constant linear velocity control algorithm is as follows: calculate the velocity error e(t) according to the actual linear velocity; calculate the compensation amount according to the velocity error According to the compensation amount Calculate the joint angular velocity correction amount through the PID algorithm According to the joint angular velocity correction amount And the compensated joint angular velocity Calculate the execution joint angular velocity w(t) of the multi-axis robotic arm.

8. The control method of the three-dimensional non-planar superconducting coil automatic winding system according to claim 7, characterized in that, The compensation amount ΔY n has the following calculation formula: Among them, represents the unit vector in the Y2-axis direction; The formula for calculating the compensated set of path points is: Among them, P' n is the compensated path point set, and θ' i,n is the i-th joint angle after the n-th turn of compensation; The obtained joint angular velocity after compensation The formula is as follows: Among them, represents the angular velocity of each joint after compensation, θ' n represents the compensated joint angle calculated according to the mapping relationship between the winding path point set P and the joint angles of the multi-axis robotic arm, θ' n =[θ' 1,n , θ' 2,n , θ' 3,n , …, θ' k,n T , is the path gradient, is the compensated path gradient.​ 9. The control method of the three-dimensional non-planar superconducting coil automatic winding system according to claim 7, characterized in that, Calculating the compensation amount based on the speed error The formula is as follows: According to the compensation amount Calculate the joint angular velocity correction amount through the PID algorithm The formula is as follows: Among them, K p is the proportional gain, K i is the integral gain, K d is the derivative gain; The described correction amount according to the joint angular velocity and the compensated joint angular velocity The formula for calculating the execution joint angular velocity w(t) of the multi-axis robotic arm is as follows: Among them, represents the corresponding compensated joint angular velocity at time t.

10. The control method of the three-dimensional non-planar superconducting coil automatic winding system according to any one of claims 5 - 6 or 8, wherein The calculation process of the constant tension algorithm is: calculate the tension error Fe(t) according to the actual tension magnitude: Fe(t) = F - Fa(t) Calculate the real-time wire pay-off torque N(t) according to the tension error Fe(t): Among them, K is the control gain coefficient, and T i is the integral time constant.

Images