Motion control method and system for liquid metal in abrasive liquid
By constructing the liquid metal droplet motion control equation, the liquid metal movement in the abrasive liquid is controlled in real time, the problem of lack of control of the movement characteristics of liquid metal during the inner wall of the runner is solved, and the processing accuracy and surface finish are improved.
Patent Information
- Application Number
- CN202411662033.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-20
- Publication Date
- 2025-02-18
AI Technical Summary
The prior art lacks a method for controlling the movement characteristics of liquid metal in the abrasive liquid during the polishing of the flow channel inner wall, resulting in insufficient processing accuracy and surface finish of the flow channel inner wall.
By obtaining the abrasive particle size, abrasive particle concentration, mass, position and motion speed in the abrasive liquid, the polynomial regression model is used to fit the relationship between the abrasive particle size and abrasive particle concentration and damping coefficient, and the damping coefficient equation and viscosity are constructed by using the polynomial regression model. Force equation, combined with net external force, feedback force and restoration force equation, build a liquid metal droplet motion control equation to control the movement speed of liquid metal droplets in real time.
By accurately controlling the movement of liquid metal droplets, the lubricity of abrasive liquid is optimized, the friction between abrasive particles and the inner wall of the runner is reduced, and the heat and waste generated during the polishing process is effectively taken away, thereby improving processing accuracy and surface finish of the inner wall of the runner is improved. .
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Figure CN119458155A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of flow channel processing, and in particular to a method and system for controlling the movement of liquid metal in abrasive liquid. Background Art
[0002] A flow channel refers to a pipeline system for the flow of fluid or gas. The surface roughness of its inner wall directly affects the flow performance of the gas or liquid in the flow channel. It is usually necessary to polish the inner wall of the flow channel to reduce the surface roughness of the inner wall of the flow channel, thereby improving the flow characteristics of the fluid. When using abrasive liquid to polish the inner wall of the flow channel, controlling the flow characteristics of the liquid metal in the abrasive liquid can not only reduce the friction between the abrasive particles in the abrasive liquid and the inner wall of the flow channel, reduce wear, and ensure that the abrasive particles in the abrasive liquid evenly contact the area to be polished, thereby achieving a more uniform polishing effect, but also effectively disperse the friction heat generated during the polishing process to prevent deformation of the inner wall of the flow channel caused by overheating.
[0003] There have been some studies on the flow characteristics of liquid metal in the prior art, but there has been no research on how to control the movement of liquid metal in abrasive liquid to improve the processing accuracy and surface finish of the inner wall of the flow channel during polishing. For example, Jie Zhang et al. electroplated a nickel layer on the surface of liquid metal locally, and controlled the electric and magnetic fields to enable it to carry hydrogel materials and achieve hydrogel transportation, such as Figure 1 As shown in (a) in the figure; Wu Jian et al. developed a wheeled rolling robot driven by liquid metal. The robot can roll on the platform driven by liquid metal, and the maximum rolling speed reaches 1.8 rad / s, as shown in Figure 1 In addition, Youyou Yao et al. designed a millimeter-scale vehicle using liquid metal droplets as wheels. The vehicle can move in a sodium hydroxide solution and can withstand a load of 0.4g during movement, as shown in (b) of the figure. Figure 1 These studies demonstrate the application and feasibility of controlling the motion characteristics of liquid metal in various scenarios, but none of them can be applied to controlling the motion characteristics of liquid metal in abrasive liquid during the polishing of the inner wall of the flow channel.
[0004] In summary, it is necessary to design a method for controlling the movement of liquid metal in abrasive liquid so that when polishing the inner wall of the flow channel, the lubricity of the abrasive liquid can be optimized by precisely controlling the movement of liquid metal, reducing the friction between the abrasive particles and the inner wall of the flow channel, and effectively removing the heat and waste generated during the polishing process, thereby improving the machining accuracy and the surface finish of the inner wall of the flow channel. Summary of the invention
[0005] Therefore, the technical problem to be solved by the present invention is to overcome the problem in the prior art that the motion characteristics of the liquid metal in the abrasive liquid are controlled when the inner wall of the flow channel is polished, thereby improving the processing accuracy.
[0006] In order to solve the above technical problems, the present invention provides a method for controlling the movement of liquid metal in abrasive liquid, comprising: Obtaining the abrasive particle size, abrasive particle concentration, mass of liquid metal droplets, position and movement speed of liquid metal droplets at time k, and target position of liquid metal droplets at time k+1; A polynomial regression model is used to fit the relationship between the abrasive particle size, the abrasive concentration and the damping coefficient to construct a damping coefficient equation; based on the damping coefficient equation and the movement speed of the liquid metal droplet at time k, a viscous force equation at time k is constructed; Based on the mass of the liquid metal droplet and the acceleration of the liquid metal droplet at time k, the net external force equation at time k is constructed; Based on the velocity feedback coefficient and the moving velocity of the liquid metal droplet at time k, the feedback force equation at time k is constructed; Based on the position of the liquid metal droplet at time k, the target position of the liquid metal droplet at time k+1, the nonlinear restoring force coefficient and the position restoring force coefficient, a restoring force equation at time k is constructed; Based on the sum of the viscosity force equation at time k, the net external force equation at time k, the feedback force equation at time k and the restoring force equation at time k being 0, constructing a liquid metal droplet motion control equation at time k; The motion control equation of the liquid metal droplet at the time k is solved to obtain the motion acceleration of the liquid metal droplet at the time k, thereby controlling the motion speed of the liquid metal droplet.
[0007] Preferably, when the polynomial regression model is a linear regression model, the damping coefficient equation is: , in, represents the damping coefficient equation; represents the base damping coefficient; It represents the influence coefficient of abrasive particle size on damping coefficient; Indicates the abrasive particle size; It represents the influence coefficient of abrasive concentration on damping coefficient; Indicates the abrasive concentration.
[0008] Preferably, when the polynomial regression model is a nonlinear regression model, the damping coefficient equation is: , in, represents the damping coefficient equation; represents the base damping coefficient; It represents the influence coefficient of abrasive particle size on damping coefficient; Indicates the abrasive particle size; Represents the influence coefficient of abrasive concentration on damping coefficient; Indicates the abrasive concentration; Represents the high-order influence coefficient of abrasive particle size on the damping coefficient; Represents the high-order influence coefficient of abrasive concentration on the damping coefficient.
[0009] Preferably, the viscosity force equation at time k is: , in, represents the viscosity force equation at time k; represents the damping coefficient equation; represents the movement speed of the liquid metal droplet at time k.
[0010] Preferably, the net external force equation at time k is: , in, represents the net external force equation at time k; represents the mass of the liquid metal droplet; represents the acceleration of the liquid metal droplet at time k.
[0011] Preferably, the feedback force equation at time k is: , in, represents the feedback force equation at time k; represents the speed feedback coefficient; represents the movement speed of the liquid metal droplet at time k.
[0012] Preferably, the restoring force equation at time k is: , in, represents the restoring force equation at time k; represents the position restoring force coefficient; represents the nonlinear restoring force coefficient; represents the position of the liquid metal droplet at time k; represents the target position of the liquid metal droplet at time k+1.
[0013] Preferably, the motion control equation of the liquid metal droplet at time k is: , in, represents the viscosity force equation at time k; represents the net external force equation at time k; represents the feedback force equation at time k; represents the restoring force equation at time k.
[0014] Preferably, after controlling the movement speed of the liquid metal droplet, the method further comprises: Acquire the actual position of the liquid metal droplet at time k+1, and calculate the difference between the actual position of the liquid metal droplet at time k+1 and the target position of the liquid metal droplet at time k+1; The position restoring force coefficient and the nonlinear restoring force coefficient are adjusted based on the difference, k=k+1 is updated, and the liquid metal droplet motion control equation at time k is reconstructed to control the movement speed of the liquid metal droplet, until the difference between the actual position of the liquid metal droplet at time k+1 and the target position of the liquid metal droplet at time k+1 is less than or equal to a preset threshold.
[0015] The present invention also provides a motion control system for liquid metal in abrasive liquid, which is used to implement the above-mentioned motion control method for liquid metal in abrasive liquid, comprising: A multi-dimensional sensor array is connected to the flow channel and is used to obtain the abrasive particle size, abrasive particle concentration, liquid metal droplet mass, and the position and movement speed of the liquid metal droplet at time k in the abrasive liquid in the flow channel; An alternating power supply, whose positive and negative electrodes are respectively connected to the two ends of the flow channel, and is used to change the positive and negative electrode directions and voltage magnitudes based on the control signal sent by the host computer, thereby changing the direction and intensity of the electric field in the flow channel to control the movement speed of the liquid metal droplets; A host computer is connected to the multi-dimensional sensor array and the alternating power supply, and specifically includes: A data receiving module, used for receiving the abrasive particle size, abrasive particle concentration, liquid metal droplet mass, and the position and movement speed of the liquid metal droplet at time k in the abrasive liquid in the flow channel; An equation construction module is used to fit the relationship between the abrasive particle size and the abrasive concentration and the damping coefficient using a polynomial regression model to construct a damping coefficient equation; construct a viscous force equation at time k based on the damping coefficient equation and the movement speed of the liquid metal droplet at time k; construct a net external force equation at time k based on the mass of the liquid metal droplet and the movement acceleration of the liquid metal droplet at time k; construct a feedback force equation at time k based on the velocity feedback coefficient and the movement speed of the liquid metal droplet at time k; construct a restoring force equation at time k based on the position of the liquid metal droplet at time k+1, the target position of the liquid metal droplet at time k+1, the nonlinear restoring force coefficient and the position restoring force coefficient; construct a liquid metal droplet motion control equation at time k based on the sum of the viscous force equation at time k, the net external force equation at time k, the feedback force equation at time k and the restoring force equation at time k being 0; The adaptive control module is used to solve the motion control equation of the liquid metal droplet at the k moment to obtain the motion acceleration of the liquid metal droplet at the k moment, and generate a control signal based on the motion acceleration of the liquid metal droplet at the k moment and send it to the alternating power supply.
[0016] The method for controlling the movement of liquid metal in abrasive liquid provided in the present application first obtains the abrasive particle size, abrasive particle concentration, mass of liquid metal droplets, position and movement speed of liquid metal droplets at time k, and target position of liquid metal droplets at time k+1 in the abrasive liquid; since the abrasive particle size and abrasive particle concentration will affect the flow resistance in the abrasive liquid, and thus affect the movement speed of liquid metal in the abrasive liquid, the present application adopts a multivariate regression method to fit the relationship between the abrasive particle size and abrasive particle concentration and the damping coefficient, so as to generate a suitable mapping relationship between the abrasive particle size, abrasive particle concentration and the movement speed of liquid metal, and constructs a viscous force equation based on the damping coefficient equation to characterize the friction force to which the liquid metal droplets are subjected when flowing in the abrasive liquid; then, a net external force equation is constructed to characterize the driving force to which the liquid metal droplets are subjected during the control process, and a feedback force equation is constructed to characterize the feedback force generated after the liquid metal droplets move based on the driving force received. At the same time, since the application of the driving force may cause the liquid metal liquid to When the flow of the droplet is unstable, the liquid metal droplet itself will generate a restoring force to return to a stable flow state. Therefore, a restoring force equation is constructed to characterize the restoring force that the liquid metal droplet is subjected to when it returns to a stable flow state after the flow is unstable. Finally, based on the mutual balance of various forces acting on the liquid metal droplet during the entire control process, a motion control equation of the liquid metal droplet is constructed. By solving the equation, the net external force required for the stable flow of the liquid metal droplet at the current moment can be obtained, and then the motion acceleration of the liquid metal droplet at the current moment can be obtained, thereby controlling the motion of the liquid metal droplet. By considering the influence of abrasive particle size and abrasive concentration on the motion of the liquid metal droplet, and considering the external force on the liquid metal droplet during the control process, as well as the feedback force and restoring force generated by the external force, the motion control equation of the liquid metal droplet is constructed, so that the acceleration, deceleration and stable motion of the liquid metal droplet can be controlled in real time and accurately, thereby improving the processing accuracy and the surface finish of the inner wall of the flow channel. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below according to specific embodiments of the present invention in conjunction with the accompanying drawings, wherein: Figure 1 A schematic diagram of the application of liquid metal motion characteristics provided in this application; wherein, Figure 1 (a) is a schematic diagram of liquid metal droplets transporting hydrogels. Figure 1 (b) is a schematic diagram of a liquid metal-driven rolling robot. Figure 1 (c) is a schematic diagram of a liquid metal-driven vehicle and cargo transportation; Figure 2 A flow chart of the method for controlling the movement of liquid metal in abrasive liquid provided in the present application; Figure 3A schematic diagram of the structure of the motion control system of liquid metal in abrasive liquid provided in this application; Figure 4 A schematic diagram of the motion control framework of a liquid metal droplet in an abrasive liquid provided in an embodiment of the present application; Figure 5 A schematic diagram of a damping coefficient fitting surface provided in an embodiment of the present application; Figure 6 A schematic diagram of the motion control results of liquid metal in abrasive liquid provided in an embodiment of the present application; wherein: Figure 6 (a) is a schematic diagram showing the position of a liquid metal droplet changing with time. Figure 6 (b) is a schematic diagram showing the change of the velocity of the liquid metal droplet over time. Figure 6 (c) is a schematic diagram of the change of the acceleration of the liquid metal droplet over time. DETAILED DESCRIPTION
[0018] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.
[0019] See also Figure 2 , Figure 2 The figure shows a flow chart of a method for controlling the movement of liquid metal in abrasive liquid provided by the present application, and the method specifically comprises: S10: obtaining the abrasive particle size, abrasive particle concentration, mass of liquid metal droplet, position and movement speed of liquid metal droplet at time k, and target position of liquid metal droplet at time k+1; S20: Use a polynomial regression model to fit the relationship between abrasive particle size and abrasive concentration and the damping coefficient, and construct a damping coefficient equation; Based on the damping coefficient equation and the movement speed of the liquid metal droplet at time k, construct a viscous force equation at time k; S30: constructing a net external force equation at time k based on the mass of the liquid metal droplet and the motion acceleration of the liquid metal droplet at time k; S40: constructing a feedback force equation at time k based on the velocity feedback coefficient and the movement velocity of the liquid metal droplet at time k; S50: constructing a restoring force equation at time k based on the position of the liquid metal droplet at time k+1, the target position of the liquid metal droplet at time k+1, the nonlinear restoring force coefficient and the position restoring force coefficient; S60: Based on the fact that the sum of the viscosity force equation at time k, the net external force equation at time k, the feedback force equation at time k and the restoring force equation at time k is 0, a control equation for the motion of the liquid metal droplet at time k is constructed; S70: solving the liquid metal droplet motion control equation at time k to obtain the motion acceleration of the liquid metal droplet at time k, thereby controlling the motion speed of the liquid metal droplet.
[0020] Specifically, since the abrasive particle size and abrasive particle concentration in the abrasive liquid affect the flow resistance in the abrasive liquid, and thus affect the movement speed of the liquid metal in the abrasive liquid, for example, when the abrasive particle size increases, the flow resistance of the abrasive liquid increases, resulting in a decrease in the movement speed of the liquid metal droplets; therefore, the present application fits the relationship between the abrasive particle size and the abrasive particle concentration and the damping coefficient to produce a suitable mapping relationship between the abrasive particle size, the abrasive particle concentration and the movement speed of the liquid metal.
[0021] Furthermore, since the influence of abrasive particle size and abrasive concentration on the damping coefficient may be linear or nonlinear, the damping coefficient equation is constructed using a polynomial regression model in the present application.
[0022] Specifically, when the polynomial regression model is a linear regression model, the damping coefficient equation is: , in, represents the damping coefficient equation; represents the base damping coefficient; It represents the influence coefficient of abrasive particle size on damping coefficient; Indicates the abrasive particle size; Represents the influence coefficient of abrasive concentration on damping coefficient; Indicates the abrasive concentration.
[0023] When the polynomial regression model is a nonlinear regression model, the damping coefficient equation is: , in, represents the damping coefficient equation; represents the base damping coefficient; It represents the influence coefficient of abrasive particle size on damping coefficient; Indicates the abrasive particle size; Represents the influence coefficient of abrasive concentration on damping coefficient; Indicates the abrasive concentration; Represents the high-order influence coefficient of abrasive particle size on the damping coefficient; Represents the high-order influence coefficient of abrasive concentration on the damping coefficient.
[0024] When constructing the damping coefficient equation using a nonlinear polynomial regression model, more complex mapping relationships are expressed by introducing square terms or higher-order terms, so that the effects of abrasive particle size and abrasive concentration on the movement speed of liquid metal droplets can be found more accurately.
[0025] Furthermore, the viscosity force equation at time k is: , in, represents the viscosity force equation at time k; represents the damping coefficient equation; represents the movement speed of the liquid metal droplet at time k.
[0026] The net external force equation at time k is: , in, represents the net external force equation at time k; represents the mass of the liquid metal droplet; represents the acceleration of the liquid metal droplet at time k.
[0027] The feedback force equation at time k is: , in, represents the feedback force equation at time k; represents the speed feedback coefficient; represents the movement speed of the liquid metal droplet at time k.
[0028] The restoring force equation at time k is: , in, represents the restoring force equation at time k; represents the position restoring force coefficient; represents the nonlinear restoring force coefficient; represents the position of the liquid metal droplet at time k; represents the target position of the liquid metal droplet at time k+1.
[0029] Since the movement behavior of liquid metal droplets in a complex fluid mechanics environment has very significant nonlinear characteristics, the present application introduces a nonlinear restoring force term based on the tanh function, which can more accurately describe the recovery process of liquid metal droplets when they move at high speeds or undergo large deformations, thereby more accurately regulating the movement of the droplets.
[0030] Furthermore, the control equation of the motion of the liquid metal droplet at time k is: , in, represents the viscosity force equation at time k; represents the net external force equation at time k; represents the feedback force equation at time k; represents the restoring force equation at time k.
[0031] Optionally, in some embodiments of the present application, after controlling the movement speed of the liquid metal droplet, the method further includes: Obtaining the actual position of the liquid metal droplet at time k+1, and calculating the difference between the actual position of the liquid metal droplet at time k+1 and the target position of the liquid metal droplet at time k+1; The position restoring force coefficient and the nonlinear restoring force coefficient are adjusted based on the difference, k=k+1 is updated, and the motion control equation of the liquid metal droplet at time k is reconstructed to control the movement speed of the liquid metal droplet, until the difference between the actual position of the liquid metal droplet at time k+1 and the target position of the liquid metal droplet at time k+1 is less than or equal to a preset threshold.
[0032] By adjusting the position restoring force coefficient and the nonlinear restoring force coefficient in the nonlinear restoring force equation in real time based on the position of the liquid metal droplet, the restoring force on the liquid metal droplet can be analyzed more accurately, thereby constructing a more accurate motion control equation and achieving high-precision liquid metal droplet motion control.
[0033] Based on the method for controlling the motion of liquid metal in abrasive liquid provided in the above embodiment, the embodiment of the present application also provides a control system for the motion of liquid metal in abrasive liquid, such as Figure 3 As shown, the system specifically includes: A multi-dimensional sensor array is connected to the flow channel and is used to obtain the abrasive particle size, abrasive particle concentration, liquid metal droplet mass, and the position and movement speed of the liquid metal droplet at time k in the abrasive liquid in the flow channel; An alternating power supply, whose positive and negative electrodes are respectively connected to the two ends of the flow channel, and is used to change the positive and negative electrode directions and voltage magnitudes based on the control signal sent by the host computer, thereby changing the direction and intensity of the electric field in the flow channel to control the movement speed of the liquid metal droplets; In one embodiment, if Figure 3 As shown in , the alternating power supply can be connected to the flow channel through a resistor, and an ammeter can be set to detect the output current of the alternating power supply in real time, and the output current value can be fed back to the host computer so that the host computer can adjust the control signal in real time according to the current value.
[0034] The host computer is connected to the multi-dimensional sensor array and the alternating power supply, and specifically includes: A data receiving module is used to receive the abrasive particle size, abrasive particle concentration, liquid metal droplet mass, and the position and movement speed of the liquid metal droplet at time k in the abrasive liquid in the flow channel; The equation construction module is used to fit the relationship between the abrasive particle size and abrasive concentration and the damping coefficient using a polynomial regression model to construct a damping coefficient equation; based on the damping coefficient equation and the movement speed of the liquid metal droplet at time k, the viscous force equation at time k is constructed; based on the mass of the liquid metal droplet and the movement acceleration of the liquid metal droplet at time k, the net external force equation at time k is constructed; based on the velocity feedback coefficient and the movement speed of the liquid metal droplet at time k, the feedback force equation at time k is constructed; based on the position of the liquid metal droplet at time k, the target position of the liquid metal droplet at time k+1, the nonlinear restoring force coefficient and the position restoring force coefficient, the restoring force equation at time k is constructed; based on the sum of the viscous force equation at time k, the net external force equation at time k, the feedback force equation at time k and the restoring force equation at time k being 0, the liquid metal droplet motion control equation at time k is constructed; The adaptive control module is used to solve the motion control equation of the liquid metal droplet at time k, obtain the motion acceleration of the liquid metal droplet at time k, and generate a control signal based on the motion acceleration of the liquid metal droplet at time k and send it to the alternating power supply.
[0035] In order to verify the effectiveness of the method for controlling the motion of liquid metal in abrasive liquid provided in the above embodiment, the present application also performed simulation in Matlab software, and the specific simulation code is as follows: % Define basic parameters m = 0.0025; % mass of liquid metal droplet, unit: kg K_q = 0.5; % Speed feedback gain coefficient K_p = 10.0; % Position restoring force constant K_r = 1.0; % nonlinear restitution coefficient q_g = 2.0; % target position, unit: mm % Fitting relationship parameters of expanded particle size, concentration and viscosity alpha = 0.001; % Particle size influence coefficient beta = 0.02; % concentration influence coefficient K2_base = 0.5; % base damping coefficient % Current particle size and concentration values d_p = 10; % particle size (in microns) C_p = 0.3; % concentration (unit: volume fraction) % Calculate the damping coefficient K2 K_2 = K2_base + alpha * d_p + beta * C_p; % Initial conditions q0 = 0.1; % Initial position q_dot0 = 0; % Initial velocity tspan = [0 3]; % simulation time interval % Define the differential equation odefun = @(t, y) [y(2); % y(1) = q, y(2) = q_dot -(K_2 + K_q) * y(2) / m - K_p * tanh(K_r * (y(1) - q_g)) / m]; % Solve the differential equation [t, y] = ode45(odefun, tspan, [q0 q_dot0]); % Drawing display figure; % Position change graph subplot(3, 1, 1); plot(t, y(:, 1), 'LineWidth', 2); xlabel('Time(s)'); ylabel('Position q (mm)'); title('Changes of droplet position over time'); % Speed change diagram subplot(3, 1, 2); plot(t, y(:, 2), 'LineWidth', 2); xlabel('Time(s)'); ylabel('Speed q (mm / s)'); title('Changes of droplet velocity over time'); % Calculate acceleration and plot acceleration = zeros(size(t)); for i = 1:length(t) acceleration(i) = -(K_2 + K_q) * y(i, 2) / m - K_p * tanh(K_r * (y(i,1) - q_g)) / m; end % Acceleration change diagram subplot(3, 1, 3); plot(t, acceleration, 'LineWidth', 2); xlabel('Time(s)'); ylabel('Acceleration q (mm / s^2)'); title('Changes in droplet acceleration over time'); grid on; like Figure 4 The figure shows a schematic diagram of the motion control framework of a liquid metal droplet in an abrasive liquid provided by an embodiment of the present application. In the figure, 1 is a summer, which is used to combine different forces together, such as the net external force and feedback force in the control equation; 2 is a mass gain module of the liquid metal droplet; 3 is an integrator, which is used to integrate acceleration and output velocity; 4 is an integrator, which is used to integrate velocity and output position; 5 is an oscilloscope display module; 6 is a velocity feedback gain module; 7 is a MatlabFunction module, whose input is the particle size. and concentration , the output is the damping coefficient 8 is a position feedback gain module; 9 is a Matlab Function module, which is used to amplify the feedback signal and apply the tanh function for nonlinear processing, output the feedback signal and pass to zoom in.
[0036] Firstly, the damping coefficient equation was constructed by simulating the relationship between abrasive particle size and abrasive particle concentration and the damping coefficient using a polynomial linear regression model. like Figure 5 The figure shows a schematic diagram of the damping coefficient fitting surface provided in this embodiment, wherein the x-axis represents the abrasive particle size, the y-axis represents the abrasive concentration, and the z-axis represents the damping coefficient; the reference damping coefficient obtained by experimental fitting , the influence coefficient of abrasive particle size on damping coefficient , the influence coefficient of abrasive concentration on damping coefficient .
[0037] Based on the damping coefficient equation, the viscosity force equation, net external force equation, feedback force equation and restoring force equation are constructed to obtain the liquid metal droplet motion control equation. Based on the control equation, the liquid metal droplet is controlled to obtain the following: Figure 6 The control result diagram is shown.
[0038] from Figure 6As can be seen from (a) in the figure, the position q of the liquid metal droplet rises rapidly in the initial stage, and quickly rises to a maximum value close to the target position about 0.5s before, and then gradually stabilizes; after nearly 1s, the position of the liquid metal droplet remains basically stable, indicating that the liquid metal droplet has reached the target position without obvious oscillation or overshoot.
[0039] from Figure 6 As can be seen from (b), the movement speed of the liquid metal droplet At the initial moment (close to 0.5s), it rapidly increases to the maximum value and then rapidly decreases, indicating that the liquid metal droplet is affected by the driving force at the initial moment and accelerates. When the movement speed reaches the maximum value, it randomly begins to decrease and gradually approaches zero, indicating that the movement speed of the liquid metal droplet gradually decreases when approaching the target position and eventually stops.
[0040] from Figure 6 As can be seen from (c), the acceleration of the liquid metal droplet is It is very large and positive at the initial moment, indicating that the liquid metal droplet is subjected to a large driving force at the initial moment and accelerates rapidly; after about 0.5s, the motion acceleration quickly becomes negative, indicating that the liquid metal droplet begins to decelerate due to the braking force after reaching the maximum speed; finally, the motion acceleration decays rapidly to zero, indicating that the liquid metal droplet is subjected to force balance when approaching the target position and reaches a stable state.
[0041] from Figure 6 It can be seen that the position of the liquid metal droplet is finally stabilized at a fixed value, indicating that the liquid metal droplet can be stably moved to the target position through the motion control method of liquid metal in abrasive liquid provided in the present application.
[0042] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.
[0043] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.
[0044] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.
[0045] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.
[0046] Obviously, the above embodiments are merely examples for the purpose of clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the present invention.
Claims
1. A method for controlling the movement of liquid metal in abrasive liquid, characterized in that: include: Obtaining the abrasive particle size, abrasive particle concentration, mass of liquid metal droplets, position and movement speed of liquid metal droplets at time k, and target position of liquid metal droplets at time k+1; A polynomial regression model is used to fit the relationship between the abrasive particle size, the abrasive concentration and the damping coefficient to construct a damping coefficient equation; based on the damping coefficient equation and the movement speed of the liquid metal droplet at time k, a viscous force equation at time k is constructed; Based on the mass of the liquid metal droplet and the acceleration of the liquid metal droplet at time k, the net external force equation at time k is constructed; Based on the velocity feedback coefficient and the moving velocity of the liquid metal droplet at time k, the feedback force equation at time k is constructed; Based on the position of the liquid metal droplet at time k, the target position of the liquid metal droplet at time k+1, the nonlinear restoring force coefficient and the position restoring force coefficient, a restoring force equation at time k is constructed; Based on the sum of the viscosity force equation at time k, the net external force equation at time k, the feedback force equation at time k and the restoring force equation at time k being 0, constructing a liquid metal droplet motion control equation at time k; The motion control equation of the liquid metal droplet at the time k is solved to obtain the motion acceleration of the liquid metal droplet at the time k, thereby controlling the motion speed of the liquid metal droplet.
2. The method for controlling the movement of liquid metal in abrasive liquid according to claim 1, characterized in that: When the polynomial regression model is a linear regression model, the damping coefficient equation is: ， in, represents the damping coefficient equation; represents the base damping coefficient; It represents the influence coefficient of abrasive particle size on damping coefficient; Indicates the abrasive grain size; Represents the influence coefficient of abrasive concentration on damping coefficient; Indicates the abrasive concentration.
3. The method for controlling the movement of liquid metal in abrasive liquid according to claim 1, characterized in that: When the polynomial regression model is a nonlinear regression model, the damping coefficient equation is: ， in, represents the damping coefficient equation; represents the base damping coefficient; It represents the influence coefficient of abrasive particle size on damping coefficient; Indicates the abrasive grain size; Represents the influence coefficient of abrasive concentration on damping coefficient; Indicates the abrasive concentration; Represents the high-order influence coefficient of abrasive particle size on the damping coefficient; Represents the high-order influence coefficient of abrasive concentration on the damping coefficient.
4. The method for controlling the movement of liquid metal in abrasive liquid according to claim 1, characterized in that: The viscosity force equation at the time k is: ， in, represents the viscosity force equation at time k; represents the damping coefficient equation; represents the movement speed of the liquid metal droplet at time k.
5. The method for controlling the movement of liquid metal in abrasive liquid according to claim 1, characterized in that: The net external force equation at time k is: ， in, represents the net external force equation at time k; represents the mass of the liquid metal droplet; represents the acceleration of the liquid metal droplet at time k.
6. The method for controlling the movement of liquid metal in abrasive liquid according to claim 1, characterized in that: The feedback force equation at time k is: ， in, represents the feedback force equation at time k; represents the speed feedback coefficient; represents the movement speed of the liquid metal droplet at time k.
7. The method for controlling the movement of liquid metal in abrasive liquid according to claim 1, characterized in that: The restoring force equation at time k is: ， in, represents the restoring force equation at time k; represents the position restoring force coefficient; represents the nonlinear restoring force coefficient; represents the position of the liquid metal droplet at time k; represents the target position of the liquid metal droplet at time k+1.
8. The method for controlling the movement of liquid metal in abrasive liquid according to claim 1, characterized in that: The governing equation for the motion of the liquid metal droplet at time k is: ， in, represents the viscosity force equation at time k; represents the net external force equation at time k; represents the feedback force equation at time k; represents the restoring force equation at time k.
9. The method for controlling the movement of liquid metal in abrasive liquid according to claim 1, characterized in that: After controlling the movement speed of the liquid metal droplet, the method further comprises: Acquire the actual position of the liquid metal droplet at time k+1, and calculate the difference between the actual position of the liquid metal droplet at time k+1 and the target position of the liquid metal droplet at time k+1; The position restoring force coefficient and the nonlinear restoring force coefficient are adjusted based on the difference, k=k+1 is updated, and the liquid metal droplet motion control equation at time k is reconstructed to control the movement speed of the liquid metal droplet, until the difference between the actual position of the liquid metal droplet at time k+1 and the target position of the liquid metal droplet at time k+1 is less than or equal to a preset threshold.
10. A motion control system for liquid metal in abrasive liquid, characterized in that: A method for controlling the movement of liquid metal in abrasive liquid according to any one of claims 1 to 9, comprising: A multi-dimensional sensor array is connected to the flow channel and is used to obtain the abrasive particle size, abrasive particle concentration, liquid metal droplet mass, and the position and movement speed of the liquid metal droplet at time k in the abrasive liquid in the flow channel; An alternating power supply, whose positive and negative electrodes are respectively connected to the two ends of the flow channel, and is used to change the positive and negative electrode directions and voltage magnitudes based on the control signal sent by the host computer, thereby changing the direction and intensity of the electric field in the flow channel to control the movement speed of the liquid metal droplets; A host computer is connected to the multi-dimensional sensor array and the alternating power supply, and specifically includes: A data receiving module, used for receiving the abrasive particle size, abrasive particle concentration, liquid metal droplet mass, and the position and movement speed of the liquid metal droplet at time k in the abrasive liquid in the flow channel; An equation construction module is used to fit the relationship between the abrasive particle size and the abrasive concentration and the damping coefficient using a polynomial regression model to construct a damping coefficient equation; construct a viscous force equation at time k based on the damping coefficient equation and the movement speed of the liquid metal droplet at time k; construct a net external force equation at time k based on the mass of the liquid metal droplet and the movement acceleration of the liquid metal droplet at time k; construct a feedback force equation at time k based on the velocity feedback coefficient and the movement speed of the liquid metal droplet at time k; construct a restoring force equation at time k based on the position of the liquid metal droplet at time k+1, the target position of the liquid metal droplet at time k+1, the nonlinear restoring force coefficient and the position restoring force coefficient; construct a liquid metal droplet motion control equation at time k based on the sum of the viscous force equation at time k, the net external force equation at time k, the feedback force equation at time k and the restoring force equation at time k being 0; The adaptive control module is used to solve the motion control equation of the liquid metal droplet at the k moment to obtain the motion acceleration of the liquid metal droplet at the k moment, and generate a control signal based on the motion acceleration of the liquid metal droplet at the k moment and send it to the alternating power supply.