CN111360833B

CN111360833B - Mechanical arm origin position calibration method and system, control terminal and mechanical arm

Info

Publication number: CN111360833B
Application number: CN202010213845.4A
Authority: CN
Inventors: 田军; 马吉宏; 方俊骅
Original assignee: Huiling Technology Shenzhen Co ltd
Current assignee: Huiling Technology Shenzhen Co ltd
Priority date: 2020-03-24
Filing date: 2020-03-24
Publication date: 2021-06-11
Anticipated expiration: 2040-03-24
Also published as: CN111360833A

Abstract

The application provides a method and a system for calibrating an original point position of a mechanical arm, a control terminal, the mechanical arm and a storage medium, relates to the technical field of computers, and can solve the problem of accuracy of finding the original point position of the mechanical arm by returning to a limit switch. The method comprises the following steps: setting an encoder at each joint of the mechanical arm, and reading first position information corresponding to the encoder at each joint; controlling each joint of the mechanical arm to move from a first position to a first preset position, and acquiring a first moving step number of the stepping motor corresponding to each joint in the moving process; determining a calibration step number corresponding to each joint according to the first moving step number, a preset joint cycle step number and a preset calibration step number; and controlling the stepping motor corresponding to each joint to move the calibration steps corresponding to each joint.

Description

Mechanical arm origin position calibration method and system, control terminal and mechanical arm

Technical Field

The application relates to the technical field of computers, in particular to a method and a system for calibrating an origin position of a mechanical arm, a control terminal and the mechanical arm.

Background

When the existing mechanical arm is driven by a stepping motor, the moving track of the existing mechanical arm is closely related to the position of an original point. Therefore, in use, the origin position of the robot arm needs to be calibrated first. At present, motor position recording is often performed with the aid of encoders. However, due to the volume limitation of the mechanical arm, a single-turn encoder is often arranged at the stepping motor end. However, after the stepping motor is powered off, the joints of the mechanical arm can still stop moving due to inertia through the speed reducer, so that the single-turn encoder cannot accurately acquire the original point position of the mechanical arm, and the problem of low precision exists when the mechanical arm returns to the limit switch to find the original point.

Disclosure of Invention

The embodiment of the application provides a method and a system for calibrating the position of an origin of a mechanical arm, a control terminal and the mechanical arm, and can effectively solve the problem that the position of the origin of the mechanical arm is inaccurate due to inertial movement after a stepping motor is powered off.

In a first aspect, the present application provides a method for calibrating an origin position of a robot arm, which is applied to a control terminal, where the robot arm includes at least one joint, each joint is controlled by a stepping motor corresponding to the joint, and an encoder is disposed at each joint, and the method includes:

reading first position information displayed by the encoder at each joint;

controlling each joint of the mechanical arm to move from a first position to a first preset position, and acquiring a first moving step number of the stepping motor corresponding to each joint in the moving process, wherein the first position is a position corresponding to the first position information, and the first preset position is a position corresponding to the first preset position information;

determining a calibration step number corresponding to each joint according to the first moving step number, a preset joint cycle step number and a preset calibration step number;

and controlling the stepping motor corresponding to each joint to move the calibration steps corresponding to each joint.

By adopting the method for calibrating the original point position of the mechanical arm, the encoder is arranged at each joint of the mechanical arm, so that the first position information of each joint can be read through the encoder, the original point position of the mechanical arm can be calibrated according to the first position information, and the inaccuracy of the original point position of the mechanical arm caused by inertial movement can be eliminated to a certain extent. Therefore, the accuracy of finding the original point position by the mechanical arm return limit switch is ensured.

In a second aspect, the present application provides a method for calibrating an origin position of a robot arm, which is applied to a robot arm including at least one joint, each joint being controlled by a stepping motor corresponding to the joint, and an encoder being disposed at each joint, the method including:

responding to a first moving instruction sent by a control terminal, and controlling the stepping motors corresponding to the joints to move from first positions to first preset positions, wherein the first moving instruction carries first position information and first preset position information, the first position information is position information displayed by the encoders at the joints, the first positions are positions corresponding to the first position information, and the first preset positions are positions corresponding to the first preset position information;

and responding to a second movement instruction sent by the control terminal, controlling the stepping motor corresponding to each joint to move the calibration step number corresponding to each joint, wherein the second movement instruction carries the calibration step number, and the calibration step number is determined by the control terminal according to the first movement step number, a preset joint cycle step number and a preset calibration step number.

In a third aspect, the present application provides a system for calibrating an origin position of a robot arm, where the system includes a control terminal and the robot arm, the robot arm includes at least one joint, each joint is controlled by a stepping motor corresponding to the joint, and an encoder is disposed at each joint;

the control terminal is used for reading first position information displayed by the encoder at each joint, acquiring a first moving step number of the stepping motor corresponding to each joint when each joint moves from a first position to a first preset position, and determining a calibration step number corresponding to each joint according to the first moving step number, a preset joint cycle step number and a preset calibration step number;

the mechanical arm is used for controlling the stepping motors corresponding to the joints to move from a first position to a first preset position after responding to a first moving instruction sent by the control terminal, and controlling the stepping motors corresponding to the joints to move the calibration steps corresponding to the joints respectively after responding to a second moving instruction sent by the control terminal;

the first moving instruction carries first position information and first preset position information, the first position is a position corresponding to the first position information, and the first preset position is a position corresponding to the first preset position information; and the second movement instruction carries the calibration step number, and the calibration step number is determined by the control terminal according to the first movement step number, a preset joint cycle step number and a preset calibration step number.

In a fourth aspect, the present application provides a control terminal comprising a processor, a memory, and a computer program stored in the memory and executable on the processor, the processor implementing the method according to the first aspect when executing the computer program.

In a fifth aspect, the present application provides a robot arm, including at least one joint, where each joint is controlled by a stepping motor corresponding to the joint, and an encoder is disposed at each joint;

the robot arm further includes: a processor, a memory and a computer program stored on the memory and executable on the processor, the computer readable storage medium storing a computer program which, when executed by the processor, implements the method of the second aspect as described above.

In a sixth aspect, the present application provides a control terminal, including:

the reading module is used for reading first position information displayed by the encoder at each joint;

the acquisition module is used for controlling each joint of the mechanical arm to move from a first position to a first preset position and acquiring a first moving step number of the stepping motor corresponding to each joint in the moving process, wherein the first position is a position corresponding to the first position information, and the first preset position is a position corresponding to the first preset position information;

the determining module is used for determining the calibration step number corresponding to each joint according to the first moving step number, the preset joint circulation step number and the preset calibration step number;

and the control module is used for controlling the stepping motor corresponding to each joint to move the calibration steps corresponding to each joint respectively.

In a seventh aspect, the present application provides a robot arm, where the robot arm includes at least one joint, each joint is controlled by a stepping motor corresponding to the joint, and an encoder is disposed at each joint, and the robot arm further includes a control module; the control module includes:

the first control unit is used for responding to a first moving instruction sent by a control terminal, and controlling the stepping motors corresponding to the joints to move from first positions to first preset positions, wherein the first moving instruction carries first position information and first preset position information, the first position information is position information displayed by the encoders at the joints, the first positions are positions corresponding to the first position information, and the first preset positions are positions corresponding to the first preset position information;

and the second control unit is used for responding to a second movement instruction sent by the control terminal, controlling the stepping motor corresponding to each joint to move the calibration step number corresponding to each joint, wherein the second movement instruction carries the calibration step number, and the calibration step number is determined by the control terminal according to the first movement step number, a preset joint circulation step number and a preset calibration step number.

It is to be understood that, the beneficial effects of the second to seventh aspects may be referred to the relevant description of the first aspect, and are not repeated herein.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.

FIG. 1 is a schematic diagram of a robotic arm according to a first embodiment of the present application;

fig. 2 is a schematic structural diagram of a system for calibrating an origin position of a robot arm according to a second embodiment of the present disclosure;

fig. 3 is a schematic flowchart of a method for calibrating an origin position of a robot arm according to a third embodiment of the present disclosure;

FIG. 4 is a flowchart illustrating an implementation of S302 in FIG. 3 in an embodiment;

FIG. 5 is a schematic flow chart illustrating the calculation of calibration steps for each joint;

fig. 6 is a schematic flowchart of a method for calibrating an origin position of a robot arm according to a third embodiment of the present application;

FIG. 7 is a flowchart illustrating an implementation of S601 in FIG. 6;

fig. 8 is a schematic structural diagram of a control terminal according to a fourth embodiment of the present application;

FIG. 9 is a schematic diagram of a control module of a robotic arm according to a fifth embodiment of the present application;

fig. 10 is a schematic diagram of a control terminal provided in a sixth embodiment of the present application;

fig. 11 is a schematic view of a control module of a robot arm according to a seventh embodiment of the present application.

Detailed Description

In the following description, for purposes of explanation and not limitation, specific details are set forth, such as particular system structures, techniques, etc. in order to provide a thorough understanding of the embodiments of the present application. It will be apparent, however, to one skilled in the art that the present application may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present application with unnecessary detail.

It should be understood that the term "and/or" as used in this specification and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items. Furthermore, in the description of the present application and the appended claims, the terms "first," "second," "third," and the like are used for distinguishing between descriptions and not necessarily for describing or implying relative importance.

It should also be appreciated that reference throughout this specification to "one embodiment" or "some embodiments," or the like, means that a particular feature, structure, or characteristic described in connection with the embodiment is included in one or more embodiments of the present application. Thus, appearances of the phrases "in one embodiment," "in some embodiments," "in other embodiments," or the like, in various places throughout this specification are not necessarily all referring to the same embodiment, but rather "one or more but not all embodiments" unless specifically stated otherwise. The terms "comprising," "including," "having," and variations thereof mean "including, but not limited to," unless expressly specified otherwise.

Before explaining the origin position calibration method of the robot arm provided by the present application, an exemplary description of the operation principle of the robot arm of the present application will be first given with reference to fig. 1.

Fig. 1 is a schematic structural diagram of a robot arm according to a first embodiment of the present application. As shown in fig. 1, the mechanical arm 1 includes a fixed end 01 and a movable end 02, the fixed end 01 and the movable end 02 are mechanically connected through a transmission device (the transmission device is not shown in the figure), the fixed end 01 includes two stepping motors 001, the movable end 02 includes two joints 002, each joint 002 is controlled by the corresponding stepping motor 001, and an encoder 20 is disposed at each joint 002.

In this embodiment, the mechanical arm 1 includes two joints 002 and two stepping motors 001 as an example, and it is understood that in other embodiments, the mechanical arm 1 may include a different number of joints, and the number of joints of the mechanical arm is designed by a manufacturer according to an application scenario of the mechanical arm, and is not limited herein.

In this application, each joint 002 moves along with its corresponding stepper motor 001, each stepper motor 001 is connected with a control module (not shown in the control module diagram), the control module controls each stepper motor 001 to move, each stepper motor 001 drives its corresponding joint 002 to move through a transmission device in the moving process, and an encoder located at each joint 002 can record the position information of the corresponding joint 002 in real time. Note that the encoder 20 records position information of each joint 002 with respect to its corresponding stepping motor 001, respectively. Wherein, the control module respectively controls each stepping motor 001 to move according to the control instruction sent by the control terminal.

It can be seen that, in the embodiment of the present application, by placing an encoder at each joint of the robot arm, the position information of each joint relative to its corresponding stepping motor can be obtained in real time, and then the origin position of the robot arm can be found according to the position information of each joint relative to its corresponding stepping motor.

The following provides an exemplary explanation of a method for calibrating the position of the origin of the robot arm according to the present invention by way of an example.

Referring to fig. 2, fig. 2 is a schematic structural diagram of a system for calibrating an origin position of a robot according to a second embodiment of the present disclosure. As shown in fig. 2, the system 20 for calibrating the origin position of the robot arm provided by the embodiment of the present application includes a control terminal 200 and a robot arm 201, where the robot arm 201 includes at least one joint, each joint is controlled by a stepping motor corresponding to the joint, and an encoder is disposed at each joint. Specifically, the structural description of the robot arm 201 can be referred to in fig. 1, and is not repeated herein;

the control terminal 200 is configured to read first position information displayed by the encoder at each joint, obtain a first moving step number of the stepping motor corresponding to each joint when each joint moves from a first position to a first preset position, and determine a calibration step number corresponding to each joint according to the first moving step number, a preset joint cycle step number, and a preset calibration step number.

In an example, after the control terminal 200 detects that the mechanical arm 201 enters the power-on state, the first position information of the encoder at each joint is read, it should be noted that, when the mechanical arm is powered off, the mechanical arm needs to pass through the speed reduction mechanism, and due to backlash of the speed reduction mechanism, there is a deviation between the first position information displayed by the encoder and the origin position of the mechanical arm, so that the origin position of the mechanical arm is inaccurately positioned. In this embodiment, according to the characteristic that the precision of the stepping motor of the mechanical arm is high in an integer number of steps, for each joint of the mechanical arm, a first moving step number corresponding to the movement of the stepping motor when the joint moves from the first position to the first preset position is obtained, so as to determine the calibration step number corresponding to the joint. It should be noted that the first moving step number is an integer number of steps.

In the present embodiment, the calibration step number corresponding to each joint is determined by the first movement step number of each stepping motor, the preset joint cycle step number, and the preset calibration step number.

The preset joint circulation step number is the moving step number of a stepping motor corresponding to the joint when the joint rotates for one circle, and the preset calibration step number is the calibration step number obtained by a manufacturer in a calibration environment before the mechanical arm leaves a factory. It is understood that the preset number of joint cycle steps and the preset number of calibration steps are usually preset by a manufacturer, and different preset values are corresponding to different joints of the mechanical arm.

The mechanical arm 201 is configured to control the stepping motors corresponding to the joints to move from the first position to the first preset position after responding to the first movement instruction sent by the control terminal 200, and control the stepping motors corresponding to the joints to move the calibration steps corresponding to the joints respectively in response to the second movement instruction sent by the control terminal 200.

It can be seen that, in this embodiment, by placing an encoder at each joint of the robot arm, the first position information of each joint relative to the corresponding stepping motor can be obtained in real time, and then the calibration step number corresponding to each joint can be determined according to the first moving step number of the corresponding stepping motor of each joint when each joint moves from the first position to the first preset position, so as to calibrate the origin position of the robot arm, and accurately find the origin position of the robot arm.

Fig. 3 is a schematic flowchart of a method for calibrating an origin position of a robot arm according to a third embodiment of the present disclosure. In this embodiment, an execution main body of the method for calibrating the origin position of the robot arm is a control device, and the control device is a computer which can directly send a control command to the robot arm and serves as an upper computer of the robot arm. The origin position calibration method of the robot arm shown in fig. 3 may include:

s301, reading first position information displayed by the encoder at each joint.

In this example, first position information of the joints relative to the corresponding stepping motors can be recorded by the encoders at each joint, and the control terminal reads the first position information.

S302, controlling each joint of the mechanical arm to move from a first position to a first preset position, and acquiring a first moving step number of the stepping motor corresponding to each joint in the moving process, wherein the first position is a position corresponding to the first position information, and the first preset position is a position corresponding to the first preset position information.

For each joint, after reading the first position information, the control terminal may perform joint movement control to obtain a first movement step number of the joint moving from the first position to a first preset position. For example, if the control terminal reads that the first position information of the joint S is a, the first preset position information is B, and the corresponding stepping motor for controlling the movement of the joint S is H, the control terminal sends a control instruction to the robot arm to control the joint S to move from the position a to the position B, and obtains a first movement step number of the stepping motor H. It should be noted that the first moving step number is an integer number of steps.

In practical applications, after the step motor of the mechanical arm is powered off, the joint of the mechanical arm needs to pass through the speed reducing mechanism to stop moving, and the backlash of the speed reducing mechanism affects the precision of the joint position, in an embodiment of the present application, in order to solve the backlash effect of the speed reducing mechanism, for any joint, first, the joint is controlled to move from the first position to a second preset position, then, the joint is controlled to move from the second preset position to the first preset position, and the backlash effect of the speed reducing mechanism is eliminated by calculating a difference value of moving steps, which is described in detail in fig. 4.

Fig. 4 is a flowchart illustrating a specific implementation of S302 in fig. 3 in an embodiment. As can be seen from fig. 3, in this embodiment, S302 includes:

and S3021, controlling each joint of the mechanical arm to move from a first position to a second preset position, and acquiring a second movement step number of the stepping motor corresponding to each joint when each joint moves from the first position to the second preset position.

The second preset position is a position corresponding to second preset position information, a distance difference between the second preset position and the first position is smaller than a distance difference between the first preset position and the first position, and a distance difference between the second preset position and the first preset position is smaller than a preset difference threshold.

In the embodiment of the present application, the influence of the backlash of the reduction mechanism on the position accuracy can be eliminated by defining the first preset position and the second preset position, and since the stepping motor has the highest accuracy in integer steps, all the moving steps acquired in the embodiment of the present application are integer steps. It should be noted that the movement of the stepping motor is divided into clockwise and counterclockwise, in this embodiment of the application, the number of steps of clockwise movement is positive, and the number of steps of counterclockwise movement is recorded as negative, for example, when any stepping motor controls the corresponding joint to move from the first position to the second preset position, the stepping motor moves 5 steps counterclockwise, and the obtained second movement step number is-5. It should be noted that backlash of the speed reduction mechanism is understood to mean a gap existing between the speed reduction mechanism and the joint or other element, that is, a displacement position deviation occurring between the speed reduction mechanism and the joint or other element.

For the displacement position deviation, the larger the displacement position deviation between the speed reduction mechanism and the joint or other element, the larger the influence on the position information deviation recorded by the encoder, and conversely, the smaller the displacement position deviation between the speed reduction mechanism and the joint or other element, the smaller the influence on the position information deviation recorded by the encoder. It will be appreciated that typically the displacement position deviation between the reduction mechanism and the joint or other element is within a preset position deviation threshold, in this embodiment the position deviation between the first position and the second preset position being equal to the preset position deviation threshold.

And S3022, controlling each joint of the mechanical arm to move from the second preset position to the first preset position, and acquiring a third moving step number of the stepping motor corresponding to each joint when each joint moves from the second preset position to the first preset position.

In the embodiment of the application, for any joint, the backlash influence of the speed reducing mechanism on the position precision is realized by arranging the second preset position between the first position and the first preset position.

S3023, calculating a sum of the absolute value of the second movement step number and the third movement step number to obtain a target movement step number.

It is to be understood that, since the second moving step number may be positive or negative, in this example, the target moving step number obtained by summing the absolute value of the second moving step number and the corresponding third moving step number when the second moving step number is moved from the second preset position to the first preset position may be regarded as the actual moving step number of the stepping motor from the power-on state to the first preset position without the backlash effect of the speed reducing mechanism.

And S303, determining the calibration step number corresponding to each joint according to the first moving step number, the preset joint cycle step number and the preset calibration step number.

For each joint, the joint is controlled to move from a first position to a first preset position, a first moving step number of a corresponding stepping motor is obtained, the first moving step number is an actual moving step number corresponding to the stepping motor which moves from power-on to the first preset position without considering the influence of backlash of a speed reducing mechanism, and the number of redundant steps to be circulated by the stepping motor can be determined by calculating the remainder between the actual moving step number and the number of circulating steps required by the stepping motor to actually move for one circle.

However, after the robot is shipped from a factory, in practical applications, the reading accuracy of the encoder is affected, and the data read by the encoder may have errors, so that the remainder is compared with the preset calibration step number, and the calibration step number is finally determined.

Further, in consideration of the backlash effect of the speed reducing mechanism, the actual number of moving steps of the stepping motor from the power-on state to the first preset position needs to be eliminated when the moving position deviation caused by the backlash effect is eliminated, specifically, the backlash effect is eliminated by setting the second preset position, and the specific elimination process is described in detail in the above S302. After the backlash influence is eliminated, determining the calibration step number corresponding to each joint according to the target moving step number, a preset joint cycle step number and a preset calibration step number.

Fig. 5 is a schematic flow chart illustrating the calculation of the calibration steps for each joint. As can be seen from fig. 5, for each of the joints, calculating the calibration step number corresponding to each joint includes:

s501, calculating the remainder between the target moving step number corresponding to the joint and the preset joint circulating step number.

The preset joint cycle step number is the moving step number of a stepping motor corresponding to the joint when the joint rotates for one circle, the target moving step number is the actual moving step number corresponding to the first preset position after the stepping motor is powered on and moves from the first position, the actual moving step number is divided by the preset joint cycle step number, the obtained remainder is the power-on position deviation value of the stepping motor, and the deviation value is correspondingly consistent with the original point position deviation value of the mechanical arm.

And S502, calculating a difference value between the remainder and the preset calibration step number, wherein the difference value is used as the calibration step number corresponding to the joint.

It can be understood that, in the use process of the mechanical arm, the precision of each joint of the mechanical arm changes with the use time, so after the power-on position deviation value of the stepping motor is obtained, the difference between the preset calibration step number and the obtained calibration step number is needed. The preset calibration steps are calibration steps acquired by a manufacturer in a calibration environment before the mechanical arm leaves a factory.

It can be understood that, in general, the precision deviation of each joint of the robot arm is within a certain controllable range during the use process, and if the precision of each joint is not within the controllable range, the robot arm is in failure and needs to be repaired.

Illustratively, whether the precision of each joint of the mechanical arm is in a controllable range or not can be determined by calculating the absolute value of the difference value and a preset difference value threshold value.

Specifically, if the absolute value of the difference is smaller than a preset difference threshold, determining the difference as the calibration step number corresponding to the joint;

and if the absolute value of the difference is larger than a preset difference threshold, sending early warning prompt information to a predetermined terminal.

S304, controlling the stepping motor corresponding to each joint to move the calibration steps corresponding to each joint respectively.

It can be seen that, in this embodiment, the actual moving step number of the stepping motor moving from the actual power-on position to the preset position is determined, the calibration step number of the stepping motor is determined according to the remainder between the actual moving step number and the preset joint cycle step number and the preset calibration step number, and the stepping motor is controlled to move according to the calibration step number, so that the calibration of the original point position of the mechanical arm is realized, and the accuracy of finding the original point position by the mechanical arm return limit switch is ensured.

Fig. 6 is a schematic flowchart of a method for calibrating an origin position of a robot arm according to a third embodiment of the present disclosure. In this embodiment, the main body of the method for calibrating the position of the origin of the robot arm is the robot arm, the robot arm includes at least one joint, each joint is controlled by a corresponding stepping motor, and an encoder is disposed at each joint. The origin position calibration method of the robot arm shown in fig. 6 may include:

s601, responding to a first moving instruction sent by a control terminal, and controlling the stepping motors corresponding to the joints to move from first positions to first preset positions, wherein the first moving instruction carries first position information and first preset position information, the first position information is position information displayed by the encoders at the joints, the first positions are positions corresponding to the first position information, and the first preset positions are positions corresponding to the first preset position information.

As shown in fig. 7, it is a flowchart of a specific implementation of S601 in fig. 6. As can be seen from fig. 7, S601 includes:

s6011, in response to a third movement instruction sent by the control terminal, control the stepping motors corresponding to the joints to move from the first positions to second preset positions, where the third movement instruction carries first position information and second preset position information, the second preset positions are positions corresponding to the second preset position information, a distance difference between the second preset positions and the first positions is smaller than a distance difference between the first preset positions and the second preset positions, and a distance difference between the second preset positions and the first preset positions is smaller than a preset difference threshold.

S6012, in response to a fourth movement instruction sent by the control terminal, control the stepping motors corresponding to the joints to move from the second preset positions to the first preset positions, where the fourth movement instruction carries the second preset position information and the first preset position information.

And S602, responding to a second movement instruction sent by the control terminal, controlling the stepping motor corresponding to each joint to move the calibration step number corresponding to each joint, wherein the second movement instruction carries the calibration step number, and the calibration step number is determined by the control terminal according to the first movement step number, a preset joint cycle step number and a preset calibration step number.

Fig. 8 is a schematic structural diagram of a control terminal according to a fourth embodiment of the present application. As can be seen from fig. 8, the control terminal 8 provided in this embodiment includes:

a reading module 801, configured to read first position information displayed by the encoder at each joint;

an obtaining module 802, configured to control each joint of the mechanical arm to move from a first position to a first preset position, and obtain a first moving step number of the stepping motor corresponding to each joint in a moving process, where the first position is a position corresponding to the first position information, and the first preset position is a position corresponding to the first preset position information;

a determining module 803, configured to determine, according to the first moving step number, a preset joint cycle step number, and a preset calibration step number, a calibration step number corresponding to each joint;

and the control module 804 is configured to control the stepping motors corresponding to the joints to move the calibration steps corresponding to the joints respectively.

In an optional implementation method, the obtaining module 802 includes:

the first obtaining unit is used for controlling each joint of the mechanical arm to move from a first position to a second preset position and obtaining a second moving step number of the stepping motor corresponding to each joint when each joint moves from the first position to the second preset position, the second preset position is a position corresponding to second preset position information, a distance difference value between the second preset position and the first position is smaller than a distance difference value between the first preset position and the second preset position, and a distance difference value between the second preset position and the first preset position is smaller than a preset difference threshold value;

and the second acquisition unit is used for controlling each joint of the mechanical arm to move from the second preset position to the first preset position and acquiring a third movement step number of the stepping motor corresponding to each joint when each joint moves from the second preset position to the first preset position.

A calculating unit, configured to calculate a sum of the absolute value of the second moving step number and the third moving step number to obtain a target moving step number;

correspondingly, the calculation module is specifically configured to:

and determining the calibration step number corresponding to each joint according to the target moving step number, the preset joint circulation step number and the preset calibration step number.

In an optional implementation manner, the computing module includes:

a first calculating unit, configured to calculate, for each joint, a remainder between the target movement step number corresponding to the joint and the preset joint cycle step number;

and the second calculating unit is used for calculating a difference value between the remainder and the preset calibration step number, and the difference value is used as the calibration step number corresponding to the joint.

In an optional implementation manner, the computing module further includes:

the first determining unit is used for determining the difference value as the calibration step number corresponding to the joint if the absolute value of the difference value is smaller than a preset difference value threshold;

and the second determining unit is used for sending early warning prompt information to a predetermined terminal if the absolute value of the difference is greater than a preset difference threshold.

Fig. 9 is a schematic structural diagram of a control module of a robot arm according to a fifth embodiment of the present application. It should be noted that the robot arm provided by the present application not only includes at least one joint and a stepping motor corresponding to each joint (see fig. 1 in particular), but also includes a control module as shown in fig. 9, where as shown in fig. 9, the control module 9 includes:

a first control unit 901, configured to control, in response to a first movement instruction sent by a control terminal, the stepping motors corresponding to the joints to move from first positions to first preset positions, where the first movement instruction carries first position information and first preset position information, the first position information is position information displayed by the encoders at the joints, the first position is a position corresponding to the first position information, and the first preset position is a position corresponding to the first preset position information;

a second control unit 902, configured to control, in response to a second movement instruction sent by the control terminal, the stepping motor corresponding to each joint to move the calibration step number corresponding to each joint, where the second movement instruction carries the calibration step number, and the calibration step number is determined by the control terminal according to the first movement step number, a preset joint cycle step number, and a preset calibration step number.

In an optional implementation manner, the first control unit 901 includes:

the first control subunit is configured to control, in response to a third movement instruction sent by the control terminal, the stepping motors corresponding to the joints to move from the first position to a second preset position, where the third movement instruction carries first position information and second preset position information, the second preset position is a position corresponding to the second preset position information, a distance difference between the second preset position and the first position is smaller than a distance difference between the first preset position and the second preset position, and a distance difference between the second preset position and the first preset position is smaller than a preset difference threshold;

and the second control subunit is configured to control, in response to a fourth movement instruction sent by the control terminal, the stepping motors corresponding to the joints to move from the second preset position to the first preset position, where the fourth movement instruction carries the second preset position information and the first preset position information.

In this application embodiment, because the actual number of steps of moving to the default position from the power-on position, the preset number of joint circulation steps and the preset calibration accuracy of the stepper motor can eliminate the deviation of the original position of the mechanical arm, the actual number of steps of moving to the default position from the power-on position is obtained first, and then the calibration step for each stepper motor can be determined according to the actual number of steps of moving, the preset number of joint circulation steps and the preset calibration accuracy, so that the original position of the mechanical arm can be accurately found.

Fig. 10 is a schematic diagram of a control terminal according to a sixth embodiment of the present application. As shown in fig. 10, the control terminal 10 of this embodiment includes: a processor 100, a memory 101 and a computer program 102 stored in said memory 101 and executable on said processor 100, such as a home position calibration program for a robot arm. The processor 100, when executing the computer program 102, implements the steps in the method embodiments shown in fig. 2 to 5, such as the steps 201 and 204 shown in fig. 2. Alternatively, the processor 100, when executing the computer program 102, implements the functions of the modules/units in the above-described apparatus embodiment shown in fig. 8.

Illustratively, the computer program 102 may be partitioned into one or more modules/units that are stored in the memory 101 and executed by the processor 100 to accomplish the present application. The one or more modules/units may be a series of computer program instruction segments capable of performing specific functions, which are used to describe the execution process of the computer program 102 in the control terminal 10. For example, the computer program 102 may be divided into a reading module, an obtaining module, a determining module and a control module, and specific functions of each module are described in the embodiment corresponding to fig. 8, which is not described herein again.

The control terminal may include, but is not limited to, a processor 100, a memory 101. It will be understood by those skilled in the art that fig. 10 is only an example of a control terminal 10 and does not constitute a limitation of the control terminal 10, and may include more or less components than those shown, or some components in combination, or different components, for example, the video processing device may also include an input-output device, a network access device, a bus, etc.

The Processor 100 may be a Central Processing Unit (CPU), other general purpose Processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), an off-the-shelf Programmable Gate Array (FPGA) or other Programmable logic device, discrete Gate or transistor logic, discrete hardware components, etc. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

The memory 101 may be an internal storage unit of the control terminal 10, such as a hard disk or a memory of the control terminal 10. The memory 101 may also be an external storage device of the control terminal 10, such as a plug-in hard disk, a Smart Media Card (SMC), a Secure Digital (SD) Card, a Flash memory Card (Flash Card), and the like, which are equipped on the control terminal 10. Further, the memory 101 may also include both an internal storage unit and an external storage device of the control terminal 10. The memory 101 is used to store the computer program and other programs and data required by the control terminal 10. The memory 101 may also be used to temporarily store data that has been output or is to be output.

Fig. 11 is a schematic diagram of a control module of a robot arm according to a seventh embodiment of the present application. It should be noted that the robot arm of this embodiment includes, in addition to the mechanism shown in fig. 1 (the structure shown in fig. 1 is not shown in fig. 11), as shown in fig. 11, a processor 110, a memory 111, and a computer program 112 stored in the memory 111 and executable on the processor 110, for example, an origin position calibration program of the robot arm. The processor 110 executes the computer program 112 to implement the steps in the method embodiments shown in fig. 6 to 7, such as the steps 601 and 602 shown in fig. 6. Alternatively, the processor 110 implements the functions of the modules/units in the above-described apparatus embodiment shown in fig. 9 when executing the computer program 112.

Illustratively, the computer program 112 may be partitioned into one or more modules/units that are stored in the memory 111 and executed by the processor 110 to accomplish the present application. The one or more modules/units may be a series of computer program instruction segments capable of performing specific functions that describe the execution of the computer program 112 in the robotic arm. For example, the computer program 112 may be divided into a first control unit and a second control unit, and specific functions of each unit are described in the embodiment corresponding to fig. 9, which is not described herein again.

The control module may include, but is not limited to, a processor 110, a memory 111. Those skilled in the art will appreciate that figure 11 is merely an example of a robotic arm 11 and does not constitute a limitation of the robotic arm 11 and may include more or fewer components than shown, or some components in combination, or different components, e.g., the video processing device may also include input output devices, network access devices, buses, etc.

The Processor 110 may be a Central Processing Unit (CPU), other general purpose Processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), an off-the-shelf Programmable Gate Array (FPGA) or other Programmable logic device, discrete Gate or transistor logic, discrete hardware components, etc. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

The memory 111 may be an internal storage unit of the robot 11, such as a hard disk or a memory of the robot 11. The memory 111 may also be an external storage device of the robot arm 11, such as a plug-in hard disk, a Smart Media Card (SMC), a Secure Digital (SD) Card, a Flash memory Card (Flash Card), and the like, provided on the robot arm 11. Further, the memory 111 may also include both an internal storage unit and an external storage device of the robot arm 11. The memory 111 is used to store the computer program and other programs and data required by the robot arm 11. The memory 111 may also be used to temporarily store data that has been output or is to be output.

An embodiment of the present invention further provides a computer-readable storage medium, in which a computer program is stored, and the computer program, when being executed by a processor, may implement the method for calibrating the origin position of the robot arm described in fig. 2 to 5, or the computer program, when being executed by the processor, may implement the method for calibrating the origin position of the robot arm described in fig. 6 and 7.

The present application provides a computer program product, which when running on a control terminal, enables the control terminal to execute the method for calibrating the origin position of the robot arm described in fig. 2 to 5, or when running on a robot arm, enables the robot arm to execute the method for calibrating the origin position of the robot arm described in fig. 6 and 7.

It will be apparent to those skilled in the art that, for convenience and brevity of description, only the above-mentioned division of the functional units and modules is illustrated, and in practical applications, the above-mentioned function distribution may be performed by different functional units and modules according to needs, that is, the internal structure of the apparatus is divided into different functional units or modules to perform all or part of the above-mentioned functions. Each functional unit and module in the embodiments may be integrated in one processing unit, or each unit may exist alone physically, or two or more units are integrated in one unit, and the integrated unit may be implemented in a form of hardware, or in a form of software functional unit. In addition, specific names of the functional units and modules are only for convenience of distinguishing from each other, and are not used for limiting the protection scope of the present application. The specific working processes of the units and modules in the system may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In the above embodiments, the descriptions of the respective embodiments have respective emphasis, and reference may be made to the related descriptions of other embodiments for parts that are not described or illustrated in a certain embodiment.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

The above-mentioned embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present application and are intended to be included within the scope of the present application.

Claims

1. The method for calibrating the position of the origin of the mechanical arm is applied to a control terminal, and is characterized in that the mechanical arm comprises at least one joint, each joint is controlled by a stepping motor corresponding to the joint, and an encoder is arranged at each joint, and the method comprises the following steps:

reading first position information displayed by the encoder at each joint;

controlling the stepping motor corresponding to each joint to move the calibration steps corresponding to each joint;

the controlling each joint of the mechanical arm to move from a first position to a first preset position and acquiring a first moving step number of the stepping motor corresponding to each joint in the moving process comprises:

controlling each joint of the mechanical arm to move from a first position to a second preset position, and acquiring a second moving step number of the stepping motor corresponding to each joint when each joint moves from the first position to the second preset position, wherein the second preset position is a position corresponding to second preset position information, a distance difference value between the second preset position and the first position is smaller than a distance difference value between the first preset position and the first position, and a distance difference value between the second preset position and the first preset position is smaller than a preset difference threshold value;

and controlling each joint of the mechanical arm to move from the second preset position to the first preset position, and acquiring a third moving step number of the stepping motor corresponding to each joint when each joint moves from the second preset position to the first preset position.

2. The method for calibrating the origin position of a robot arm according to claim 1, wherein said acquiring a third number of steps of movement of the stepping motor corresponding to each of the joints when each of the joints moves from the second preset position to the first preset position comprises:

calculating the sum of the absolute value of the second moving step number and the third moving step number to obtain a target moving step number;

correspondingly, the determining the calibration step number corresponding to each joint according to the first moving step number, the preset joint cycle step number and the preset calibration step number includes:

3. The method for calibrating the origin position of a robot arm according to claim 2, wherein said determining the calibration step number corresponding to each of the joints based on the target moving step number, a preset joint cycle step number, and a preset calibration step number comprises:

for each joint, calculating the remainder between the target moving step number corresponding to the joint and the preset joint cycle step number;

and calculating a difference value between the remainder and the preset calibration step number, wherein the difference value is used as the calibration step number corresponding to the joint.

4. The method of calibrating an origin position of a robot arm according to claim 3, comprising, after said calculating a difference between the remainder and the preset calibration step number:

if the absolute value of the difference is smaller than a preset difference threshold, determining the difference as the calibration step number corresponding to the joint;

5. The method for calibrating the position of the origin of the mechanical arm is applied to the mechanical arm and is characterized in that the mechanical arm comprises at least one joint, each joint is controlled by a stepping motor corresponding to the joint, and an encoder is arranged at each joint, and the method comprises the following steps:

responding to a second movement instruction sent by the control terminal, controlling the stepping motor corresponding to each joint to move the calibration step number corresponding to each joint, wherein the second movement instruction carries the calibration step number, and the calibration step number is determined by the control terminal according to the first movement step number, a preset joint cycle step number and a preset calibration step number;

the step motor corresponding to each joint is controlled to move in response to a first movement instruction sent by a control terminal, and the step motor comprises:

responding to a third movement instruction sent by the control terminal, controlling the stepping motors corresponding to the joints to move from the first position to a second preset position, wherein the third movement instruction carries first position information and second preset position information, the second preset position is a position corresponding to the second preset position information, a distance difference value between the second preset position and the first position is smaller than a distance difference value between the first preset position and the second preset position, and a distance difference value between the second preset position and the first preset position is smaller than a preset difference threshold value;

and responding to a fourth movement instruction sent by the control terminal, and controlling the stepping motors corresponding to the joints to move from the second preset position to the first preset position, wherein the fourth movement instruction carries the second preset position information and the first preset position information.

6. An origin position calibration system of a robot arm, the system comprising a control terminal and a robot arm, the control terminal being configured to implement the origin position calibration method of the robot arm according to any one of claims 1 to 4, the robot arm being configured to implement the origin position calibration method of the robot arm according to claim 5, the robot arm comprising at least one joint, each of the joints being controlled by a stepping motor corresponding thereto, and an encoder being provided at each of the joints;

7. A control terminal, characterized in that it comprises a processor, a memory and a computer program stored in the memory and executable on the processor, which when executed by the processor implements the method according to any one of claims 1 to 4.

8. The mechanical arm is characterized by comprising at least one joint, wherein each joint is controlled by a stepping motor corresponding to the joint, and an encoder is arranged at each joint;

the robot arm further comprising a processor, a memory, and a computer program stored on the memory and executable on the processor, the computer readable storage medium having stored thereon the computer program, wherein the computer program when executed by the processor implements the method of claim 5.