Torque compensation method, device and equipment for electric screw driver and storage medium

Abstract

The invention relates to the technical field of motor torque control, and discloses a torque compensation method, device and equipment of an electric screw driver and a storage medium. The method comprises the following steps: acquiring a preset locking moment set by a user; calculating a compensation torque according to the historical motor angular velocity of the motor of the electric screw driver and the dynamic relationship between the motor and the load; superposing the preset locking moment and the compensation moment to obtain a target locking moment; and controlling a motor of the electric screw driver to generate the target locking torque. According to the embodiment of the invention, the precision of the locking torque of the electric screw driver can be improved, so that the torque does not exceed the limit in the locking process.

Description

Technical Field

[0001] The present application relates to the technical field of motor torque control, and in particular to a torque compensation method, device, equipment and storage medium for an electric screwdriver. Background Art

[0002] An electric screwdriver can effectively improve the operation efficiency of workers. In particular, the emergence of a micro-torque screwdriver is used in the final stage of tightening a screw to ensure that the screw or bolt can be tightened. However, if it is necessary to improve the screwing yield of the micro-torque screwdriver, precise torque control of the output torque is required.

[0003] In the related art, usually the output torque of the motor of the electric screwdriver is used as the final locking torque, without considering the dynamic index in the locking process, resulting in an excessive locking torque. Summary of the Invention

[0004] The purpose of the present application is to provide a torque compensation method, device, equipment and storage medium for an electric screwdriver, aiming to improve the accuracy of the locking torque of the electric screwdriver so that the torque in the locking process does not exceed the limit.

[0005] The embodiment of the present application provides a torque compensation method for an electric screwdriver, including: Obtain a preset locking torque set by a user; Calculate a compensation torque according to the historical motor angular velocity of the motor of the electric screwdriver and the dynamic relationship between the motor and the load; Superimpose the preset locking torque and the compensation torque to obtain a target locking torque; Control the motor of the electric screwdriver to generate the target locking torque.

[0006] In one embodiment, before calculating the compensation torque according to the historical motor angular velocity of the motor of the electric screwdriver and the dynamic relationship between the motor and the load, it further includes: Periodically sample the motor angular velocity of the motor to obtain the historical motor angular velocities at multiple historical moments.

[0007] In one embodiment, calculating the compensation torque according to the historical motor angular velocity of the motor of the electric screwdriver and the dynamic relationship between the motor and the load includes: Determine the offset between the preset locking torque and the torque transmitted to the workpiece at the historical moment according to the historical motor angular velocity and the dynamic relationship between the motor and the load, to obtain the compensation torque.

[0008] In one embodiment, determining the offset between the preset locking torque and the torque transmitted to the workpiece at the historical moment according to the historical motor angular velocity and the dynamic relationship between the motor and the load includes: Calculating the frictional torque and the accelerating torque of the motor at the historical moment according to the historical motor angular velocity; the accelerating torque is the torque required to generate corresponding accelerations for the motor shaft and the load; Superposing the frictional torque and the accelerating torque of the motor at the historical moment to obtain the compensation torque.

[0009] In one embodiment, the calculation formula for the compensation torque is: , wherein, is the compensation torque, is the friction coefficient, is the historical motor angular velocity, is the combined inertia of the motor shaft and the load, is the frictional torque of the motor at the historical moment, is the accelerating torque of the motor at the historical moment.

[0010] In one embodiment, calculating the frictional torque and the accelerating torque of the motor at the historical moment according to the historical motor angular velocity includes: Calculating the frictional torque and the accelerating torque of the motor at the previous historical moment according to the historical motor angular velocity at the previous historical moment; or fitting the historical motor angular velocities at multiple historical moments according to the change rate of the historical motor angular velocity, and calculating the frictional torque and the accelerating torque of the motor at the previous historical moment according to the fitted historical motor angular velocity.

[0011] In one embodiment, controlling the motor of the electric screwdriver to generate the target locking torque includes: Generating a current loop control command for causing the motor to generate the target locking torque, and outputting the current loop control command to the motor.

[0012] The embodiment of the present application further provides a torque compensation device for an electric screwdriver, including: A first module, configured to obtain a preset locking torque set by a user; A second module, configured to calculate a compensation torque according to the historical motor angular velocity of the motor of the electric screwdriver and the dynamic relationship between the motor and the load; A third module, configured to superpose the preset locking torque and the compensation torque to obtain a target locking torque; A fourth module, configured to control the motor of the electric screwdriver to generate the target locking torque.

[0013] An embodiment of the present application further provides an electronic device, which includes a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, the torque compensation method of the electric screwdriver described above is implemented.

[0014] An embodiment of the present application further provides a computer-readable storage medium, which stores a computer program, and when the computer program is executed by a processor, the torque compensation method of the electric screwdriver described above is implemented.

[0015] Advantages of the present application: By calculating the compensation torque based on the historical motor angular velocity of the motor of the electric screwdriver and the dynamic relationship between the motor and the load, controlling the motor of the electric screwdriver to generate a target locking torque obtained by superimposing a preset locking torque and the compensation torque, so that the locking torque acting on the workpiece does not exceed the motor electromagnetic torque of the motor, improving the accuracy of the locking torque of the electric screwdriver, so that the torque during the locking process does not exceed the limit. Description of the Drawings

[0016] Figure 1 is an application scenario diagram of the torque compensation method of the electric screwdriver provided by the embodiment of the present application.

[0017] Figure 2 is a flowchart of the torque compensation method of the electric screwdriver provided by the embodiment of the present application.

[0018] Figure 3 is a schematic structural diagram of the torque compensation device of the electric screwdriver provided by the embodiment of the present application.

[0019] Figure 4 is a schematic hardware structure diagram of the electronic device provided by the embodiment of the present application. Detailed Embodiments

[0020] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0021] It should be noted that although the functional modules are divided in the device schematic diagram and the logical order is shown in the flowchart, in some cases, the steps shown can be executed in a different order from the module division in the device or the flowchart. Terms such as "first" and "second" in the description, claims and drawings are used to distinguish similar objects and are not used to describe a specific order or sequence.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terms used herein are for the purpose of describing embodiments of this application only and are not intended to limit this application.

[0023] The application scenarios of the torque compensation method for the electric screwdriver provided by the embodiments of this application will be introduced below. Figure 1 It is an application scenario diagram of the torque compensation method for the electric screwdriver provided by the embodiments of this application. Refer to Figure 1 , in this application scenario, an electric screwdriver is included. The electric screwdriver is configured with a motor driver 1 and a motor 2. The motor 2 is used to torsionally cooperate with an external load through a motor shaft. In this embodiment, the motor driver 1 is used to obtain a preset locking torque set by the user, calculate a compensation torque based on the historical motor angular velocity of the motor 2 of the electric screwdriver and the dynamic relationship between the motor 2 and the load, superimpose the preset locking torque and the compensation torque to obtain a target locking torque, and control the motor 2 of the electric screwdriver to generate the target locking torque.

[0024] The technical solutions of this application and how the technical solutions of this application solve the above technical problems will be described in detail below with specific embodiments. These specific embodiments below can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of this application will be described below with reference to the accompanying drawings.

[0025] Figure 2 It is a flowchart of the torque compensation method for the electric screwdriver provided by the embodiments of this application. Refer to Figure 2 , in one embodiment, the method includes but is not limited to steps S201 to S204.

[0026] Step S201, obtain the preset locking torque set by the user.

[0027] The locking torque refers to the torque (moment) applied by the electric screwdriver when tightening a screw, that is, the magnitude of the rotational force required to lock the screw to the workpiece. It is a key parameter in the screw tightening process and directly affects the connection quality and reliability of the screw. The preset locking torque refers to the locking torque set by the user through the electric screwdriver. It can be set by operating the torque setting module of the electric screwdriver to set the preset locking torque, or by interacting with an external torque setting module, and the external torque setting module sets the preset locking torque of the electric screwdriver. The embodiments of this application do not make limitations.

[0028] The user operates the electric screwdriver directly or indirectly to generate a torque setting instruction including a corresponding preset locking torque and transmit it to the motor driver of the electric screwdriver, so that the electric screwdriver generates the corresponding preset locking torque when operated. It can be understood that after receiving the torque setting instruction, the electric screwdriver drives the motor to generate the corresponding preset locking torque, that is, the motor electromagnetic torque of the motor is equal to the preset locking torque set by the user. When the electric screwdriver locks the screw to the workpiece, the locking torque acting on the workpiece will be less than the motor electromagnetic torque of the motor. Therefore, there is an offset between the locking torque acting on the workpiece and the motor electromagnetic torque of the motor.

[0029] Step S202: Calculate the compensation torque according to the historical motor angular velocity of the motor of the electric screwdriver and the dynamic relationship between the motor and the load.

[0030] It can be understood that since there is a corresponding offset between the locking torque acting on the workpiece and the motor electromagnetic torque of the motor, during the process of the electric screwdriver locking the screw to the workpiece, in order to make the locking torque acting on the workpiece not exceed the motor electromagnetic torque of the motor, an additional compensation torque is superimposed on the preset locking torque to increase the motor electromagnetic torque of the motor. Calculating the compensation torque according to the historical motor angular velocity of the motor of the electric screwdriver and the dynamic relationship between the motor and the load may be to determine the offset term between the locking torque acting on the workpiece and the preset locking torque according to the dynamic relationship between the motor and the load, substitute the historical motor angular velocity of the motor of the electric screwdriver into the corresponding offset term for offset calculation, and use the calculated offset as the compensation torque.

[0031] In one embodiment, before step S202, it further includes: periodically sampling the motor angular velocity of the motor to obtain the historical motor angular velocities at multiple historical moments.

[0032] Periodically sampling the motor angular velocity of the motor can be achieved by sensor solutions such as encoders, Hall sensors or tachogenerators, or by the back electromotive force method to deduce the motor angular velocity of the motor through the induced voltage of the motor winding. After obtaining the sampling signal, periodically acquire the sampled sampling signal, and calculate the historical motor angular velocity at this historical moment through the sampling signal.

[0033] In one embodiment, step S202 includes: determining the offset between the preset locking torque at the historical moment and the torque transmitted to the workpiece according to the historical motor angular velocity and the dynamic relationship between the motor and the load, to obtain the compensation torque.

[0034] Determine the offset term between the locking torque acting on the workpiece and the preset locking torque according to the dynamic relationship between the motor and the load, including the friction torque term and the acceleration torque term. Substitute the historical motor angular velocity into the friction torque term and the acceleration torque term to calculate the offset between the preset locking torque at the historical moment and the torque transmitted to the workpiece, which is used as the compensation torque at the current moment.

[0035] In one embodiment, according to the historical motor angular velocity and the dynamic relationship between the motor and the load, determine the offset between the preset locking torque at the historical moment and the torque transmitted to the workpiece, including: calculating the friction torque and the acceleration torque of the motor at the historical moment according to the historical motor angular velocity; superimposing the friction torque and the acceleration torque of the motor at the historical moment to obtain the compensation torque. Among them, the acceleration torque is the torque required to generate the corresponding acceleration of the motor shaft and the load.

[0036] In a specific embodiment, the calculation formula of the compensation torque is: , where, is the compensation torque, is the friction coefficient, is the historical motor angular velocity, is the combined inertia of the motor shaft and the load, is the friction torque of the motor at the historical moment, is the acceleration torque of the motor at the historical moment.

[0037] The compensation torque is set based on the deviation between the preset locking torque set by the user and the torque transmitted to the workpiece. The dynamic equation of the motor of the electric screwdriver is: , where, is the output torque of the motor, , is the preset locking torque, is the torque transmitted to the workpiece, is the current motor angular velocity, is the friction torque of the motor at the current moment, is the acceleration torque of the motor at the current moment.

[0038] Due to and existing, it can be seen that the torque transmitted to the workpiece during operation is not equal to the output torque of the motor (i.e., the preset locking torque). Even during deceleration, due to and is a negative value, resulting in the torque transmitted to the workpiece exceeding the output torque of the motor. Therefore, in order to ensure that the torque transmitted to the workpiece does not exceed the output torque of the motor during the entire operation, a compensation torque is superimposed on the preset locking torque. This compensation torque is equal to the sum of the acceleration torque of the motor at the historical moment and the frictional torque of the motor at the historical moment, increasing the output torque of the motor and reducing the deviation between the output torque of the motor and the torque transmitted to the workpiece.

[0039] In one embodiment, calculating the frictional torque and acceleration torque of the motor at the historical moment based on the historical motor angular velocity includes: calculating the frictional torque and acceleration torque of the motor at the previous historical moment based on the historical motor angular velocity at the previous historical moment; or fitting the historical motor angular velocities at multiple historical moments according to the change rate of the historical motor angular velocity, and calculating the frictional torque and acceleration torque of the motor at the previous historical moment based on the fitted historical motor angular velocity.

[0040] Calculating the frictional torque and acceleration torque of the motor at the previous historical moment based on the historical motor angular velocity at the previous historical moment can be to substitute the historical motor angular velocity obtained from the most recent acquisition into the frictional torque term and the acceleration torque term after converting it into angular velocity form, so as to calculate the offset between the preset locking torque and the torque transmitted to the workpiece at the previous historical moment as the compensation torque at the current moment. Calculating the frictional torque and acceleration torque of the motor at the previous historical moment based on the fitted historical motor angular velocity can be to weight and fit the historical motor angular velocities at multiple historical moments into a fitted angular velocity according to the change rate and direction of the historical motor angular velocity, and substitute the fitted angular velocity into the frictional torque term and the acceleration torque term, so as to calculate the offset between the preset locking torque and the torque transmitted to the workpiece at the previous historical moment as the compensation torque at the current moment.

[0041] Step S203: Superimpose the preset locking torque and the compensation torque to obtain the target locking torque.

[0042] After superimposing the preset locking torque and the compensation torque, the expression of the current motor angular velocity of the motor and the dynamic relationship between the motor and the load is: , , where is the target locking torque.

[0043] Step S204: Control the motor of the electric screwdriver to generate the target locking torque.

[0044] In one embodiment, step S204 includes: generating a current loop control command for the motor to generate the target locking torque, and outputting the current loop control command to the motor.

[0045] Please refer toFigure 3 , an embodiment of the present application further provides a torque compensation device for an electric screwdriver, which can implement the torque compensation method of the above electric screwdriver. The device includes: A first module 301, configured to obtain a preset locking torque set by a user; A second module 302, configured to calculate a compensation torque according to the historical motor angular velocity of the motor of the electric screwdriver and the dynamic relationship between the motor and the load; A third module 303, configured to superimpose the preset locking torque and the compensation torque to obtain a target locking torque; A fourth module 304, configured to control the motor of the electric screwdriver to generate the target locking torque.

[0046] The specific implementation manner of the torque compensation device of the electric screwdriver is basically the same as that of the specific embodiment of the torque compensation method of the above electric screwdriver, and will not be elaborated here.

[0047] Figure 4 is a schematic diagram of the hardware structure of an electronic device provided by an embodiment of the present application.

[0048] Next, refer to Figure 4 to describe the electronic device 400 according to this embodiment of the present disclosure.

[0049] Figure 4 The electronic device 400 shown is only an example and should not impose any limitations on the functions and usage scope of the embodiments of the present disclosure.

[0050] As Figure 4 shown, the electronic device 400 is presented in the form of a general-purpose computing device. The components of the electronic device 400 may include, but are not limited to: at least one processing unit 410, at least one storage unit 420, a bus 430 connecting different system components (including the storage unit 420 and the processing unit 410), a display unit 440, etc.

[0051] Among them, the storage unit stores program code, and the program code can be executed by the processing unit 410, so that the processing unit 410 executes the steps according to various exemplary embodiments of the present disclosure described in the torque compensation method part of the above electric screwdriver in this specification.

[0052] The storage unit 420 may include a readable medium in the form of a volatile storage unit, such as a random access storage unit (RAM) 4201 and / or a cache storage unit 4202, and may further include a read-only storage unit (ROM) 4203.

[0053] The storage unit 420 may also include a program / utilities 4204 having a set (at least one) of program modules 4205. Such program modules 4205 include, but are not limited to: an operating system, one or more application programs, other program modules, and program data. Each or some combination of these examples may include an implementation of a network environment.

[0054] The bus 430 may represent one or more of several types of bus structures, including a memory bus or memory controller, a peripheral bus, an accelerated graphics port, a processing unit, or a local bus using any of a variety of bus structures.

[0055] The electronic device 400 may also communicate with one or more external devices 400' (such as a keyboard, a pointing device, a Bluetooth device, etc.), and may also communicate with one or more devices that enable a user to interact with the electronic device 400, and / or communicate with any device that enables the electronic device 400 to communicate with one or more other computing devices (such as a router, a modem, etc.). Such communication may be carried out through an input / output (I / O) interface 450. In addition, the electronic device 400 may also communicate with one or more networks (such as a local area network (LAN), a wide area network (WAN), and / or a public network, such as the Internet) through a network adapter 460. The network adapter 460 may communicate with other modules of the electronic device 400 through the bus 430. It should be understood that, although not shown in the figure, other hardware and / or software modules may be used in conjunction with the electronic device 400, including but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage systems, etc.

[0056] An embodiment of the present application also provides a computer-readable storage medium storing a computer program, which when executed by a processor implements the torque compensation method of the electric screwdriver described above.

[0057] The torque compensation method, device, equipment, and storage medium of the electric screwdriver provided by the embodiment of the present application calculate a compensation torque according to the historical motor angular velocity of the motor of the electric screwdriver and the dynamic relationship between the motor and the load, and control the motor of the electric screwdriver to generate a target locking torque obtained by superimposing a preset locking torque and the compensation torque, so that the locking torque acting on the workpiece does not exceed the motor electromagnetic torque of the motor, improving the accuracy of the locking torque of the electric screwdriver, so that the torque does not exceed the limit during the locking process.

[0058] From the description of the above embodiments, those skilled in the art can easily understand that the exemplary embodiments described herein can be implemented by software, or by a combination of software and necessary hardware. Therefore, the technical solutions according to the embodiments of the present disclosure can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (which can be a CD-ROM, a USB flash drive, a mobile hard disk, etc.) or on a network, including several instructions to enable a computing device (which can be a personal computer, a server, or a network device, etc.) to execute the above method according to the embodiments of the present disclosure.

[0059] The program product can adopt any combination of one or more readable media. The readable media can be a readable signal medium or a readable storage medium. The readable storage medium can be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination of the above. More specific examples (non-exhaustive list) of the readable storage medium include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0060] The computer-readable storage medium may include a data signal propagated in a baseband or as a part of a carrier wave, in which the readable program code is carried. Such a propagated data signal can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. The readable storage medium can also be any readable medium other than the readable storage medium, which can send, propagate, or transmit a program for use by or in combination with an instruction execution system, apparatus, or device. The program code contained on the readable storage medium can be transmitted by any appropriate medium, including but not limited to wireless, wired, optical cable, RF, etc., or any suitable combination of the above.

[0061] Those skilled in the art can understand that the above-mentioned modules can be distributed in the device according to the description of the embodiments, or can be correspondingly changed and distributed in one or more devices that are uniquely different from this embodiment. The modules of the above embodiments can be combined into one module, or further split into multiple sub-modules.

[0062] The above specifically shows and describes the exemplary embodiments of the present disclosure. It should be understood that the present disclosure is not limited to the detailed structures, settings, or implementation methods described herein; on the contrary, the present disclosure is intended to cover various modifications and equivalent settings included within the spirit and scope of the appended claims.

Claims

1. A torque compensation method for an electric screwdriver, characterized in that: include: Obtaining the preset locking torque set by the user; Calculating a compensation torque based on a historical motor angular velocity of a motor of the electric screwdriver and a dynamic relationship between the motor and a load; Superimposing the preset locking torque and the compensation torque to obtain a target locking torque; The motor of the electric screwdriver is controlled to generate the target locking torque.

2. The torque compensation method of an electric screwdriver according to claim 1, characterized in that: Before calculating the compensation torque according to the historical motor angular velocity of the motor of the electric screwdriver and the dynamic relationship between the motor and the load, the method further includes: The motor angular velocity of the motor is periodically sampled to obtain historical motor angular velocities at multiple historical moments.

3. The torque compensation method of an electric screwdriver according to claim 1, characterized in that: The calculating of the compensation torque according to the historical motor angular velocity of the motor of the electric screwdriver and the dynamic relationship between the motor and the load comprises: According to the historical motor angular velocity and the dynamic relationship between the motor and the load, the offset between the preset locking torque and the torque transmitted to the workpiece at the historical moment is determined to obtain the compensation torque.

4. The torque compensation method of an electric screwdriver according to claim 3, characterized in that: The determining, based on the historical motor angular velocity and the dynamic relationship between the motor and the load, an offset between the preset locking torque and the torque transmitted to the workpiece at a historical moment, comprises: Calculating the friction torque and acceleration torque of the motor at a historical moment according to the historical motor angular velocity; the acceleration torque is the torque required to make the motor shaft and the load generate corresponding acceleration; The compensation torque is obtained by superimposing the friction torque and the acceleration torque of the motor at the historical moment.

5. The torque compensation method of an electric screwdriver according to claim 4, characterized in that: The calculation formula of the compensation torque is: ， in, To compensate the torque, is the friction coefficient, is the historical motor angular velocity, is the combined inertia of the motor shaft and the load, is the friction torque of the motor at the historical moment, is the acceleration torque of the motor at the historical moment.

6. The torque compensation method of an electric screwdriver according to claim 4, characterized in that: The calculating the friction torque and acceleration torque of the motor at a historical moment according to the historical motor angular velocity comprises: The friction torque and acceleration torque of the motor at the previous historical moment are calculated based on the historical motor angular velocity at the previous historical moment; or the historical motor angular velocities at multiple historical moments are fitted according to the change rate of the historical motor angular velocity, and the friction torque and acceleration torque of the motor at the previous historical moment are calculated based on the fitted historical motor angular velocities.

7. The torque compensation method of an electric screwdriver according to claim 1, characterized in that: The controlling the motor of the electric screwdriver to generate the target locking torque comprises: A current loop control instruction is generated to enable the motor to generate the target locking torque, and the current loop control instruction is output to the motor.

8. A torque compensation device for an electric screwdriver, characterized in that: include: The first module is used to obtain a preset locking torque set by a user; A second module is used to calculate the compensation torque according to the historical motor angular velocity of the motor of the electric screwdriver and the dynamic relationship between the motor and the load; A third module is used to superimpose the preset locking torque and the compensation torque to obtain a target locking torque; The fourth module is used to control the motor of the electric screwdriver to generate the target locking torque.

9. An electronic device, characterized in that: The electronic device comprises a memory and a processor, wherein the memory stores a computer program, and the processor implements the torque compensation method for the electric screwdriver according to any one of claims 1 to 7 when executing the computer program.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the torque compensation method for the electric screwdriver according to any one of claims 1 to 7 is implemented.

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