CN113601551B - Mechanical arm tail end motion performance evaluation and measurement device and method - Google Patents

Abstract

The invention discloses a device and a method for evaluating and measuring the motion performance of the tail end of a mechanical arm. Through the measuring device, the repeated positioning precision measurement of the tail ends of the single arm and the double arms of the mechanical arm can be measured. Meanwhile, a camera is added, and the device can be used for measuring the motion response error of the mechanical arm and the speed error of the two arms. The measuring device provided by the invention has the advantages of simple structure, multiple testing functions and high testing precision.

Description

A device and method for evaluating and measuring the motion performance of the end of a mechanical arm

technical field

The invention relates to the field of robot arm positioning, in particular to a device and method for evaluating and measuring the motion performance of the end of a robot arm.

Background technique

In recent years, with the industrial upgrading and the further development of the intelligent manufacturing industry. The demand for robotic arms in the industry is also increasing. As one of the representatives of intelligent automatic control equipment, the robotic arm is widely used in industry, commerce, agriculture, aerospace and other fields. Robotic arms can replace humans in repetitive, dangerous tasks. In order to ensure the reliable operation of the manipulator, it is necessary to evaluate and measure the end motion performance of the manipulator. Among them, the repetitive positioning accuracy of the end of the manipulator is one of the important indicators of the manipulator, which is closely related to the competent work of the manipulator. Due to the wear and tear of the manipulator during long-term operation and the aging of the equipment, the repeated positioning accuracy of the end of the manipulator will continue to decrease. The reduction of this indicator will affect the performance of terminal tasks. In order to ensure that the repetitive positioning accuracy of the end of the robotic arm is kept within the required range during use, it is necessary to measure the repetitive positioning accuracy of the end. Considering the specific execution tasks of the end of the manipulator, the trajectory tracking accuracy is also one of the key indicators. It is necessary to measure the trajectory tracking accuracy of the end of the manipulator to evaluate the end motion execution ability of the manipulator. At present, the repetitive positioning accuracy and trajectory tracking accuracy of the end of the robotic arm mainly rely on methods such as wire-drawn encoders, visual measurement, and laser trackers. Among them, the pull wire encoder has a complex mechanism and high operation requirements; the binocular vision measurement is expensive and low in accuracy; the laser tracker equipment is expensive and the measurement cost is high. In addition, dual-arm robots have emerged in new applications such as human-machine collaboration and human-like services in recent years. In addition to the end repeat positioning accuracy and trajectory tracking accuracy indicators, the motion response speed error between the arms is also a key indicator. This index reflects the synchronicity of the dual-arm cooperative task, and is the basic index of the dual-arm cooperative task. Due to factors such as controllers, actuators, and structures, the two arms of the dual-arm robot will cause the end execution time to be asynchronous.

For example, the patent document of application publication number CN201810321280.4 discloses a device and method for measuring the repetitive positioning accuracy of the end of an industrial robot. The invention uses a laser transmitter and a reflector to replace high-cost optical equipment through high-precision image acquisition, and the mechanical structure design replaces complex algorithm calculations, reducing equipment costs. However, due to the use of laser transmitters and pan/tilts, the equipment is inconvenient to carry and the cost is still high.

For example, the patent document with the application publication number CN201911065792.X provides a device for measuring the repetitive positioning accuracy of the end effector of the robotic arm, including a probe-type measuring device, a clamping device, a probe ball at the end of the robotic arm, and a computer. The invention can realize the repeated positioning accuracy measurement of the end of a single arm at a single fixed position, but it cannot realize the repeated positioning accuracy measurement of multiple positions at the end of the mechanical arm.

For example, the patent document with the application publication number CN110328669B discloses a method and device for collecting and tracking the end trajectory of a robot used for practical training. The invention uses a camera to obtain the trajectory of the robot end through image processing. However, the accuracy of the end position obtained by this method is poor, and it is not suitable for the measurement occasions that require high end accuracy.

Contents of the invention

Aiming at the technical problems in the prior art of low measurement accuracy, complex mechanism, single measurement index, relatively expensive equipment and not easy to carry, the present invention proposes a device and method for evaluating and measuring the motion performance of the end of a mechanical arm. The specific technical solution is as follows:

A measuring device for evaluating and measuring the kinematic performance of the end of a mechanical arm, the device includes a planar movement measuring device, a measuring ball head, a data acquisition and motion control box, and a control terminal;

The plane movement measuring device comprises a Y-axis left guide rail, a Y-axis right guide rail, a Y-axis motor guide rod, an X-axis guide rail, an X-axis motor guide rod, a base slide block and a three-dimensional measuring device; the Y-axis left guide rail and the Y-axis motor guide rod The right axis guide rail is arranged in parallel on both sides of the Y-axis motor guide rod, and the two ends of the X-axis guide rail are respectively embedded in the Y-axis left guide rail and the Y-axis right guide rail, which can be left The guide rail and the Y-axis right guide rail move along the Y-axis direction, and the Y-axis motor guide rod is connected to the X-axis guide rail through a ball screw nut pair; the X-axis motor guide rod is fixed on the X-axis guide rail, The base slider is embedded in the chute of the X-axis guide rail, and is connected with the X-axis motor guide rod through a ball screw nut pair;

The three-dimensional measuring device includes a measuring table mounting frame and three measuring tables, the bottom of the measuring table mounting frame is fixed on the base slider, and the top of the measuring table mounting frame is a three-dimensional triangular pyramid shape. One side plate, three measuring tables are respectively fixed on the three side plates, and the measuring axes of the three measuring tables are perpendicular to each other, and the measuring axis of each measuring table is also perpendicular to the corresponding side plate;

The measuring ball head is used to be fixed on the end of the mechanical arm during measurement, and ensure that the measuring ball head is in contact with the probes at the ends of the three measuring gauges;

The data acquisition and motion control box is used for electrical connection with three measuring meters, the X-axis motor guide rod and the Y-axis motor guide rod, and the control terminal is used for electrical connection with the mechanical arm and the data acquisition and motion control box , the control terminal is used to control the various components of the entire control device and calculate the measurement data.

Further, there are two planar movement measuring devices and two measuring ball heads, respectively corresponding to the left arm and the right arm of the mechanical arm.

Further, a camera is also included, the camera is also electrically connected to the computing terminal, and the camera is used to collect moving images of the end of the mechanical arm.

Further, a camera is also included, the camera is also electrically connected to the computing terminal, and the camera is used to collect moving images of the end of the mechanical arm.

A method for measuring the repetitive positioning accuracy of the end of a mechanical arm, the method is implemented based on the above-mentioned device, and the method specifically includes the following steps:

(1) multiple test positions are set, and at each test position, the control terminal first controls the movement of the X-axis motor guide rod and the Y-axis motor guide rod to drive the slider of the measurement base to move to the test position, and then The control terminal then controls the end of the mechanical arm to move to the same testing position, and makes the measuring ball head contact the tips of the three measuring gauges; then move to the next measuring position and repeat the above operations; during this process, the data Acquisition and motion control box collects the data of three measuring tables;

(2) Establish a rectangular coordinate system, the X-axis is along the length direction of the X-axis motor guide rod, the Y-axis is along the length direction of the Y-axis motor guide rod, and the Z-axis is the vertical direction. Solve the following equations and discard unreasonable solutions. Get the center coordinates of the measuring ball head, which is the end coordinates of the robot arm (x ₁ , y ₁ , z ₁ ):

Among them, (x _c1 , y _c1 , z _c1 ), (x _c2 , y _c2 , z _c2 ), (x _c3 , y _c3 , z _c3 ) are the center coordinates of the three hemispheres at the tip of the measuring ball, and R is The radius of the measuring ball head, r is the radius of the hemispherical surface of the tip of the measuring meter, (x _r1 , y _r1 , z _r1 ) is the coordinates of the intersection of the axes of the three measuring meters and the inner surface of the side plate of the measuring meter mounting frame; l _r1 , l _r2 and l _r3 are the distances from the center of the tip hemisphere of the three measuring meters to the inner surface of the side plate of the measuring meter mounting frame when the measuring ball head is in contact with the three measuring meters; among them, (x _r , y _r , z _r ) is the coordinates of the center S _r of the equilateral triangle formed by the intersection of the axes of the three measuring meters and the inner surface of the side plate of the measuring meter mounting frame, and l is the side length of the equilateral triangle; x _r , y _r are read by reading the X axis The angle values of the motor guide rod and the Y-axis motor guide rod are converted, and z _r is obtained according to the structural parameters of the entire measuring device.

(3) According to the coordinates (x ₁ , y ₁ , z ₁ ) of the end of the manipulator calculated at each test position of the base slider and the standard position of the end of the manipulator when the end of the manipulator is still at the same test position By comparison, the end positioning error at each test position at the end of the manipulator is obtained.

A method for measuring a motion response error at the end of a mechanical arm, the method is implemented based on the above-mentioned device, and the method specifically includes the following steps:

(1) According to the structure of the manipulator, define several key points on each shaft and joint, so that several key points are connected in turn, and the arranged shape is used as the motion feature of a single manipulator;

(2) During measurement, the control terminal controls the movement of the mechanical arm, the X-axis motor guide rod, and the Y-axis motor guide rod, thereby driving the end of the mechanical arm and the base slider to move, and the camera monitors the end of the mechanical arm in real time. Taking pictures; during this process, the data of three measurement tables is collected through the data acquisition and motion control box; the control terminal recognizes the motion trajectory characteristics of the mechanical arm according to the built-in feature tracking algorithm, and certain changes occur in the motion trajectory characteristics of the current and subsequent frames. change, and the change lasts for several frames, it is considered that the robotic arm has responded to the start command issued by the control terminal, and at this time, record the time stamp of the first frame of the change, which is the movement start time stamp; the current and subsequent frames The motion trajectory features of the motion trajectory do not change for several consecutive frames, and it is considered that the robot arm has executed the stop command issued by the control terminal. At this time, the time stamp of the first frame of the several consecutive frames that does not change is recorded, and the time stamp is the motion end timestamp;

(3) Statistically calculate the error between the start command issued by the control terminal and the start timestamp, and the error between the stop command issued by the control terminal and the end timestamp, to obtain the motion response error of the end of the mechanical arm.

A method for measuring the velocity error at the end of a mechanical arm, the method is implemented based on the above-mentioned device, and the method specifically includes the following steps:

(1) According to the structure of the manipulator, define several key points on each shaft and joint, so that several key points are connected in turn, and the arranged shape is used as the motion feature of a single manipulator;

(2) During measurement, the control terminal controls the movement of the mechanical arm, the X-axis motor guide rod, and the Y-axis motor guide rod, thereby driving the end of the mechanical arm and the base slider to move, and the camera monitors the end of the mechanical arm in real time. Take pictures, and ensure that the control terminal sends motion commands to the two robotic arms at the same time; during the motion process, the data of the three measurement meters is collected through the data acquisition and motion control box; the control terminal recognizes the The motion trajectory characteristics of the two robotic arms, when the motion trajectory characteristics of the front and rear frames change to a certain extent, and the change lasts for several frames, it is considered that the robotic arm has responded to the start command issued by the control terminal, and the changed information is recorded at this time. The time stamp of the first frame, which is the start time stamp of the movement; the motion trajectory characteristics of the current and subsequent frames do not change for several consecutive frames, and it is considered that the mechanical arm has executed the stop command issued by the control terminal, and the continuous record is recorded at this time. The timestamp of the first frame of several frames that do not change, which is the timestamp of the end of motion;

(3) Statistically collect the data of the three measuring tables collected by the motion control box and the position data of the measuring base slider respectively, and obtain the real position coordinate data of the end of the double arm at each moment; Fit the real position coordinate data to obtain the trajectory of the end of the arms, calculate the first derivative of the position trajectory, and obtain the velocity trajectory of the end of the arms; then according to the respective starting moments and movement time intervals of the arms, the end of the arms can be obtained The speed of the speed at the same moment and the same time interval of the movement are the respective error situations in the two cases.

The beneficial effects of the present invention are as follows:

(1) The present invention can meet the evaluation and measurement of three key indicators of the end motion performance of a dual-arm robot, including end repeat positioning accuracy, trajectory tracking accuracy, and dual-arm response speed error.

(2) The mechanism of the present invention is relatively simple, easy to disassemble, carry and install, and the cost is lower compared with measuring equipment such as laser base stations.

(3) The device of the present invention can realize the automatic measurement of multi-point repetitive positioning accuracy, without repeated disassembly and assembly, and can realize the repetitive accuracy measurement of multiple positions with only three measuring meters.

Description of drawings

FIG. 1 is a schematic diagram of Embodiment 1 of the device for evaluating and measuring the kinematic performance of the end of a mechanical arm according to the present invention.

Fig. 2 is the perspective view of planar mobile measuring device;

Fig. 3 is the top view of planar mobile measuring device;

Fig. 4 is the schematic diagram that measuring ball head contacts with three measuring tables;

Fig. 5 is a schematic diagram of Embodiment 2 of the measurement device for evaluating the kinematic performance of the end of the mechanical arm.

Fig. 6 is a schematic diagram of Embodiment 3 of the measurement device for evaluating the kinematic performance of the end of the mechanical arm.

Fig. 7 is a schematic diagram of Embodiment 4 of the measurement device for evaluating the kinematic performance of the end of the mechanical arm.

In the figure, a planar mobile measuring device 1, a measuring ball head 2, a data acquisition and motion control box 3, a control terminal 4, a dual-arm robot 5, a camera 6, a three-axis measuring device 101, an X-axis fixing seat 102, and a sliding base for measuring Block 103, Y-axis left guide rail 104, Y-axis motor guide rod 105, Y-axis holder 106, Y-axis right guide rail 107, X-axis guide rail 108, X-axis motor guide rod 109, measuring table mount 1011, measuring table 1012.

Detailed ways

The present invention will be described in detail below with reference to the accompanying drawings and preferred embodiments, and the purpose and effect of the present invention will become clearer. It should be understood that the specific embodiments described here are only used to explain the present invention and are not intended to limit the present invention.

Embodiment one

A device for evaluating and measuring the motion performance of the end of a double arm. The measured object is a dual-arm robot 5 and other robots of the same type. , camera 6, as shown in FIG. 1 .

As shown in Figure 2, the planar movement measuring device 1 includes a three-axis measuring device 101, an X-axis fixed seat 102, a measurement base slider 103, a Y-axis left guide rail 104, a Y-axis motor guide rod 105, a Y-axis fixed seat 106, Y-axis right guide rail 107, X-axis guide rail 108, X-axis motor guide rod 109. The Y-axis left guide rail 104 and the Y-axis right guide rail 107 are respectively arranged on the left and right sides of the Y-axis fixed seat 106, and the upper parts of the Y-axis left guide rail 104 and the Y-axis right guide rail 107 are provided with Y-axis slide grooves, and the X-axis guide rail 108 The middle part passes through the ball screw nut pair and the Y-axis motor guide rod 105, and the left and right sections of the X-axis guide rail 108 are respectively clamped in the Y-axis chute of the Y-axis left guide rail 104 and the Y-axis right guide rail 107, and the X-axis guide rail 108 follows The Y-axis motor guide rod 105 is driven to move linearly along the Y-axis direction. The X-axis guide rail 108 fixes the X-axis holder 102, the two ends of the X-axis motor guide rod 109 are fixed on the X-axis holder 102, and the measuring base slider 103 is connected with the X-axis motor guide rod 109 through a ball screw nut pair and can be Driven by the X-axis motor guide rod 109, it moves linearly along the X-axis direction. The three-axis measurement device 101 is fixed on the top of the measurement base slider 103 by screws.

As shown in Figures 3 and 4, the three-axis measuring device 101 includes a measuring table mounting base 1011 and three measuring tables 1012. The bottom of the measuring table mounting base 1011 is fixed with the measuring base slider 103 by screws, and the measuring table mounting frame 1011 is fixed. The top is composed of three side plates in the shape of a regular triangular pyramid. Three measuring tables 1012 are respectively fixed on the three side plates. The measuring axes of the three measuring tables 1012 are perpendicular to each other. The board is vertical. The measuring gauge 1012 is a dial indicator or a dial indicator, and the measuring ball head 2 is installed at the end of the mechanical arm to be tested, and is in contact with the probes at the ends of the three measuring gauges 1012 during use.

The measuring ball head 2 is used to be fixed at the end of the mechanical arm during measurement, and to ensure that the measuring ball head is in contact with the probes at the ends of the three measuring gauges 1012 .

The data acquisition and motion control box 3 is connected to three measuring meters 1012 through data lines, and the data acquisition and motion control box 3 is connected to the Y-axis motor guide rod 105 and the X-axis motor guide rod 109 to collect and control the measurement on the plane mobile measuring device 1 X-axis and Y-axis coordinate positions of the base slider 103 .

The method for measuring the repetitive positioning accuracy of the end of the mechanical arm based on the set of measuring devices of this embodiment includes the following measuring steps:

Step 1: Assemble the measuring device and set multiple test positions. At each test position, the control terminal 4 first controls the movement of the X-axis motor guide rod 109 and the Y-axis motor guide rod 105 to drive the slider 103 of the measurement base to move to The test position, then the control terminal 4 controls the end of the mechanical arm to move to the same test position, and makes the measuring ball head contact with the tips of the three measuring tables; then move to the next measuring position and repeat the above operations; During this process, the data acquisition and motion control box collects the data of the three measurement meters;

Step 2: Measure the radius of the ball head 2 as R, the tip of the measuring gauge 1012 is a hemispherical surface, and the radius of the hemispherical surface is r, and the measuring axes of the three measuring gauges 1012 are perpendicular to each other and intersect at one point and are aligned with the inner surface of the measuring gauge mounting seat 1011 Vertically, the axes of the three measuring tables 1012 are connected to the three intersection points on the inner surface of the measuring table mounting seat 1011 to form an equilateral triangle, the side length of the triangle is l, and the lower left corner of the plane motion measuring device 1 is taken as the origin, and the In a Cartesian coordinate system, the normal line of the center of the measuring base slider 103 on its top passes through the center S of an equilateral triangle, wherein the coordinates of the center S _r of the planar motion measuring device 1 are (x _r , y _r , z _r ), and the plane The coordinates of the intersection points of the axes of the three measuring gauges 1012 on the motion measuring device 1 and the inner surface of the side plate of the measuring gauge mounting seat 1011 are (x _r1 , y _r1 , z _r1 ), (x _r2 , y _r2 , z _r2 ), ( x _r3 , y _r3 , z _r3 ), the distances from the center of the ends of the three measuring gauges 1012 to the inner surface of the measuring gauge mount 1011 are l _r1 , l _r2 , l _r3 when the contact of the measuring ball head is in place, and the three measuring gauges The intersection coordinates of the axis and the side plate are:

The center coordinates of the ends of the three measuring tables are:

Assuming that the center coordinates of the measuring ball head 2 at the end of the dual-arm robot 5 are (x ₁ , y ₁ , z ₁ ), according to the contact constraint relationship between the measuring ball head 2 and the three measuring tables 1012:

Step 3: Solve the above equation to obtain the coordinates of the measuring ball head 2 at the end of the dual-arm robot 5, discard unreasonable solutions, and obtain accurate coordinate values;

Step 4: According to the obtained coordinates (x ₁ , y ₁ , z ₁ ) of the end of the manipulator calculated at each test position of the base slider and the standard position of the end of the manipulator when the end of the manipulator is still at the same test position By comparison, the end positioning error at each test position at the end of the manipulator is obtained.

Embodiment two

As shown in FIG. 5 , on the basis of Embodiment 1, a set of measuring devices is added, which can be used to measure the repeated positioning accuracy of the arms. The specific measurement method is also the same as that of Embodiment 1. However, at this time, compared with single-arm positioning accuracy measurement, when both arms perform positioning accuracy measurement at the same time, they will be constrained by the mutual position of the two arms.

Embodiment Three

A camera 6 is added on the basis of the measuring device in the first embodiment, which can be used to measure the motion response error of the end of the mechanical arm. The specific measurement device is shown in Figure 6. The measurement method of the motion response error specifically includes the following steps:

Step 1: Add a camera 6 on the basis of the device in Embodiment 1, the camera 6 is connected to the control terminal 4, and is directly controlled by the control terminal 4;

Step 2: According to the structure of the robot arm, define several key points on each shaft and joint, so that several key points are connected in sequence, and the arranged shape is used as the movement feature of a single robot arm;

Step 3: During measurement, the control terminal 4 controls the movement of the mechanical arm of the dual-arm robot 5, the X-axis motor guide rod 109, and the Y-axis motor guide rod 105, thereby driving the measuring ball head 2 and the measuring base at the end of the mechanical arm The slide block 103 moves, and the camera 6 takes pictures of the mechanical arm in real time, and all devices are uniformly timed by the control terminal 4; in this process, the data of three measurement tables 1012 are collected by the data acquisition and motion control box 3; The control terminal 4 recognizes the motion trajectory characteristics of the mechanical arm according to the built-in feature tracking algorithm. When the motion trajectory characteristics of the current and subsequent frames change to a certain extent, and the change lasts for several frames, it is considered that the mechanical arm has responded to the start of the control terminal 4. Instruction, record the time stamp of the first frame that changes at this time, and the time stamp is the movement start time stamp; the motion trajectory characteristics of the current and subsequent frames do not change for several consecutive frames, and it is considered that the robotic arm has executed the control terminal. At this time, record the time stamp of the first frame of the consecutive frames that do not change, and the time stamp is the end time stamp of the motion;

Step 4: Count the error between the start command issued by the control terminal 4 and the start time stamp, and the error between the stop command issued by the control terminal 4 and the end time stamp, respectively, and obtain the motion response of the end of the mechanical arm error.

Embodiment Four

On the basis of Embodiment 2, a camera 6 can also be added, and the resulting measurement device is shown in Figure 7, so as to test the speed error at the end of both arms. The measurement method specifically includes the following steps:

Step 1: Add a camera 6 on the basis of the device described in Embodiment 2, and the camera is controlled by the control terminal 4;

Step 2: According to the structure of the robot arm, define several key points on each shaft and joint, so that several key points are connected in sequence, and the arranged shape is used as the movement feature of a single robot arm;

Step 3: During measurement, the control terminal 4 controls the movement of the left and right mechanical arms, the X-axis motor guide rod 109, and the Y-axis motor guide rod 105 of the dual-arm robot 5, thereby driving the measuring ball head 2 and the measuring base at the end of the mechanical arm. The seat slider 103 moves, the camera 6 takes pictures of the mechanical arms in real time, and ensures that the control terminal 4 sends motion instructions to the two mechanical arms at the same time, and all devices are uniformly timed by the control terminal 4; during the movement, through The data collection and motion control box 3 collects the data of three measurement tables 1012 in the two planar mobile measurement devices 1; the control terminal 4 recognizes the motion track characteristics of the left and right arms of the dual-arm robot 5 according to the built-in feature tracking algorithm. When the motion trajectory characteristics of the next frame change to a certain extent, and the change lasts for several frames, it is considered that the robotic arm has responded to the start command issued by the control terminal. At this time, the timestamp of the first frame where the change occurs is recorded, and the timestamp It is the movement start time stamp; the motion trajectory characteristics of the current and subsequent frames do not change for several consecutive frames, it is considered that the robot arm has executed the stop command issued by the control terminal, and at this time record the first frame of the several consecutive frames that do not change The time stamp of , which is the end time stamp of the movement;

Step 4: Statistically collect the data of the three measurement tables 1012 and the position data of the measurement base slider 103 through the data acquisition and motion control box 3 respectively, and obtain the real position coordinate data of the center of the measuring ball head 2 at the end of the arms at each moment; Fit the real position coordinate data of the ends of the arms at each moment to obtain the trajectory of the ends of the arms, and calculate the first-order derivative of the position trajectory to obtain the velocity trajectory of the ends of the arms; then according to the respective starting moments of the arms As well as the movement time interval, the respective error conditions of the speed of the ends of the arms at the same time and the same time interval of movement can be obtained. The error includes numerical error and direction deviation.

Those of ordinary skill in the art can understand that the above description is only a preferred example of the invention, and is not intended to limit the invention. Although the invention has been described in detail with reference to the foregoing examples, for those skilled in the art, it can still be understood. The technical solutions described in the foregoing examples are modified, or some of the technical features are equivalently replaced. All modifications, equivalent replacements, etc. within the spirit and principles of the invention shall be included in the scope of protection of the invention.

Claims (2)

1. A method for measuring the motion response error at the end of a mechanical arm, characterized in that the method is implemented based on a measuring device for evaluating the motion performance of the end of the mechanical arm, and the measuring device for evaluating the motion performance of the end of the mechanical arm includes a planar movement measuring device, a measuring ball head , data acquisition and motion control box and control terminal; The plane movement measuring device comprises a Y-axis left guide rail, a Y-axis right guide rail, a Y-axis motor guide rod, an X-axis guide rail, an X-axis motor guide rod, a base slide block and a three-dimensional measuring device; the Y-axis left guide rail and the Y-axis motor guide rod The right-axis guide rail is arranged in parallel on both sides of the Y-axis motor guide rod, and the two ends of the X-axis guide rail are respectively embedded in the Y-axis left guide rail and the Y-axis right guide rail. The Y-axis right guide rail moves along the Y-axis direction, and the Y-axis motor guide rod is connected to the X-axis guide rail through a ball screw nut pair; the X-axis motor guide rod is fixed on the X-axis guide rail, and the Y-axis motor guide rod is fixed on the X-axis guide rail. The base slider is embedded in the chute of the X-axis guide rail, and is connected with the X-axis motor guide rod through a ball screw nut pair; The three-dimensional measuring device includes a measuring table mounting frame and three measuring tables, the bottom of the measuring table mounting frame is fixed on the base slider, and the top of the measuring table mounting frame is a three-dimensional triangular pyramid shape. One side plate, three measuring tables are respectively fixed on the three side plates, and the measuring axes of the three measuring tables are perpendicular to each other, and the measuring axis of each measuring table is also perpendicular to the corresponding side plate; The measuring ball head is used to be fixed on the end of the mechanical arm during measurement, and ensure that the measuring ball head is in contact with the probes at the ends of the three measuring gauges; The data acquisition and motion control box is used for electrical connection with three measuring meters, the X-axis motor guide rod and the Y-axis motor guide rod, and the control terminal is used for electrical connection with the mechanical arm and the data acquisition and motion control box , the control terminal is used to control the movement of the mechanical arm, the X-axis motor guide rod, and the Y-axis motor guide rod, and calculate the measurement data; The device for evaluating and measuring the motion performance of the end of the mechanical arm also includes a camera, which is also electrically connected to the control terminal, and the camera is used to collect moving images of the end of the mechanical arm; The method for measuring the motion response error at the end of the mechanical arm specifically includes the following steps: (1) According to the structure of the manipulator, define several key points on each shaft and joint, so that several key points are connected in sequence, and the arranged shape is used as the movement feature of a single manipulator; (2) During measurement, the control terminal controls the movement of the mechanical arm, the X-axis motor guide rod, and the Y-axis motor guide rod, thereby driving the end of the mechanical arm and the base slider to move, and the camera monitors the end of the mechanical arm in real time. Taking pictures; during this process, the data of three measurement tables is collected through the data acquisition and motion control box; the control terminal recognizes the motion trajectory characteristics of the mechanical arm according to the built-in feature tracking algorithm, and certain changes occur in the motion trajectory characteristics of the current and subsequent frames. change, and the change lasts for several frames, it is considered that the robotic arm has responded to the start command issued by the control terminal, and at this time, record the time stamp of the first frame of the change, which is the movement start time stamp; the current and subsequent frames The motion trajectory features of the motion trajectory do not change for several consecutive frames, and it is considered that the robot arm has executed the stop command issued by the control terminal. At this time, the time stamp of the first frame of the several consecutive frames that does not change is recorded, and the time stamp is the motion end timestamp; (3) Count the error between the start command issued by the control terminal and the start time stamp, and the error between the stop command issued by the control terminal and the end time stamp, respectively, to obtain the motion response error of the end of the mechanical arm. 2. A method for measuring the velocity error at the end of a mechanical arm, characterized in that the method is realized based on a measurement device for evaluating the motion performance of the end of the mechanical arm, and the measurement device for evaluating the motion performance of the end of the mechanical arm includes a planar movement measuring device, a measuring ball Head, data acquisition and motion control box and control terminal; The plane movement measuring device comprises a Y-axis left guide rail, a Y-axis right guide rail, a Y-axis motor guide rod, an X-axis guide rail, an X-axis motor guide rod, a base slide block and a three-dimensional measuring device; the Y-axis left guide rail and the Y-axis motor guide rod The right-axis guide rail is arranged in parallel on both sides of the Y-axis motor guide rod, and the two ends of the X-axis guide rail are respectively embedded in the Y-axis left guide rail and the Y-axis right guide rail. The Y-axis right guide rail moves along the Y-axis direction, and the Y-axis motor guide rod is connected to the X-axis guide rail through a ball screw nut pair; the X-axis motor guide rod is fixed on the X-axis guide rail, and the Y-axis motor guide rod is fixed on the X-axis guide rail. The base slider is embedded in the chute of the X-axis guide rail, and is connected with the X-axis motor guide rod through a ball screw nut pair; The three-dimensional measuring device includes a measuring table mounting frame and three measuring tables, the bottom of the measuring table mounting frame is fixed on the base slider, and the top of the measuring table mounting frame is a three-dimensional triangular pyramid shape. One side plate, three measuring tables are respectively fixed on the three side plates, and the measuring axes of the three measuring tables are perpendicular to each other, and the measuring axis of each measuring table is also perpendicular to the corresponding side plate; The measuring ball head is used to be fixed on the end of the mechanical arm during measurement, and ensure that the measuring ball head is in contact with the probes at the ends of the three measuring gauges; The data acquisition and motion control box is used for electrical connection with three measuring meters, the X-axis motor guide rod and the Y-axis motor guide rod, and the control terminal is used for electrical connection with the mechanical arm and the data acquisition and motion control box , the control terminal is used to control the movement of the mechanical arm, the X-axis motor guide rod, and the Y-axis motor guide rod, and calculate the measurement data; The plane moving measuring device and the measuring ball head are two, respectively corresponding to the left arm and the right arm of the mechanical arm; The device for evaluating and measuring the motion performance of the end of the mechanical arm also includes a camera, which is also electrically connected to the control terminal, and the camera is used to collect moving images of the end of the mechanical arm; The method for measuring the speed error at the ends of the two arms of the mechanical arm specifically includes the following steps: (1) According to the structure of the manipulator, define several key points on each shaft and joint, so that several key points are connected in sequence, and the arranged shape is used as the movement feature of a single manipulator; (2) During measurement, the control terminal controls the movement of the mechanical arm, the X-axis motor guide rod, and the Y-axis motor guide rod, thereby driving the end of the mechanical arm and the base slider to move, and the camera monitors the end of the mechanical arm in real time. Take pictures, and ensure that the control terminal sends motion commands to the two robotic arms at the same time; during the motion process, the data of the three measurement meters is collected through the data acquisition and motion control box; the control terminal recognizes the The motion trajectory characteristics of the two robotic arms, when the motion trajectory characteristics of the front and rear frames change to a certain extent, and the change lasts for several frames, it is considered that the robotic arm has responded to the start command issued by the control terminal, and the changed information is recorded at this time. The time stamp of the first frame, which is the start time stamp of the movement; the motion trajectory characteristics of the current and subsequent frames do not change for several consecutive frames, and it is considered that the mechanical arm has executed the stop command issued by the control terminal, and the continuous record is recorded at this time. The timestamp of the first frame of several frames that do not change, which is the timestamp of the end of motion; (3) Statistically collect the data of the three measurement tables collected by the data collection and the motion control box and the position data of the base slider to obtain the real position coordinate data of the end of the double arm at each moment; the real position data of the end of the double arm at each moment Fit the position coordinate data to obtain the position trajectory of the end of the arms, calculate the first-order derivative of the position trajectory, and obtain the velocity trajectory of the end of the arms; The respective error conditions under the two situations of speed at the same moment and the same time interval as motion.

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