CN205734940U - A kind of online fast calibration device of TCP being applied to industrial robot - Google Patents

Abstract

The utility model discloses a TCP online rapid calibration device applied to industrial robots, which comprises a control cabinet, a TCP calibration device, an industrial robot, terminal tools and a control bus. The control cabinet is respectively connected to the TCP calibration device and the industrial robot through the control bus. The tool is installed on the industrial robot; the TCP calibration device includes a TCP detection device, a calibration controller and an installation base. The TCP detection device is fixedly installed on one side of the industrial robot through the installation base, and the measurement plane is parallel to the XOY plane of the industrial robot's base coordinate system. According to the on-off signal of the through-beam photoelectric sensor, record the flange pose data, calculate and compensate the pose deviation of the end tool in the X/Y axis and Z axis direction, and reduce the TCP calibration error through repeated operations, effectively Improve the working accuracy of industrial robots, reduce the downtime and maintenance time of industrial robots, and improve the automation of industrial production lines.

Description

A TCP online rapid calibration device applied to industrial robots

technical field

The invention relates to an industrial robot terminal tool calibration technology, in particular to a TCP online rapid calibration method and device applied to an industrial robot.

Background technique

With the rapid development of industrial robot technology, it has gradually been more and more widely used in welding, cutting, assembly and other fields. By installing different end tools, industrial robots can complete a variety of tasks. Among them, the pose calibration accuracy of the Tool Center Point (TCP) directly affects the operation accuracy of the industrial robot.

After working for a long time, the end tools of industrial robots (such as stud welding guns, cutting tools, etc.) will have certain posture deviations, which will cause problems such as the inability of industrial robots to complete preset functions. At present, the calibration of the end tool TCP of industrial robots mainly adopts the multi-point method of offline manual teaching. In this method, the TCP of the end tool of the industrial robot is first aligned to a fixed point, and then the TCP calibration is realized by adjusting the joint angle of the industrial robot. However, this method has certain disadvantages: (1) The TCP calibration process of the multi-point method is mainly affected by human factors (such as operating experience, etc.), which inevitably introduces large errors; (2) The calibration process takes a long time , will affect the production efficiency of industrial robots; (3) in order to achieve periodic calibration of the production line, it will consume a lot of human resources and reduce the overall production capacity of the production line. The fast online and accurate calibration of industrial robot TCP is directly related to the product quality and production efficiency of the production line. Therefore, it is urgent to propose a TCP fast online calibration method applied to industrial robots, which can not only ensure the working accuracy of industrial robots, but also improve the quality of industrial robots. degree of automation.

Contents of the invention

In order to solve the deficiencies in the prior art, the object of the present invention is to provide a TCP online rapid calibration method and device applied to industrial robots that can realize the degree of freedom calibration of industrial robot TCP.

In order to achieve the above object, the present invention adopts the following technical solutions:

A TCP online rapid calibration device applied to industrial robots, including a control cabinet, a TCP calibration device, an industrial robot, an end tool and a control bus, the control cabinet is respectively connected to the TCP calibration device and the industrial robot through the control bus, and the end tool is installed on the On the industrial robot; the TCP calibration device includes a TCP detection device, a calibration controller and a mounting base, the TCP detection device is fixedly installed on one side of the industrial robot through the mounting base, and the measurement plane is parallel to the XOY plane of the industrial robot base coordinate system.

The above-mentioned TCP detection device includes a device upper cover, a device body, an accuracy inspection switch and four groups of opposite-beam photoelectric sensors. The accuracy inspection switch is arranged on the upper surface of the device body. The beam-type photoelectric sensors are respectively arranged on the longitudinal centerline of the inner side of the device body, and the laser rays of the beam-type photoelectric sensors are perpendicular to each other and on the same horizontal plane.

The above-mentioned calibration controller includes a device shell, a microcontroller unit, a display unit, a key unit, a status indicator light and a communication interface, and the calibration controller obtains the output signal of the precision inspection switch and the on-off signal of four groups of through-beam photoelectric sensors , communicate with the control cabinet through the control bus connected to the communication interface, and feed back the working information through the display unit and status indicator light.

A TCP online rapid calibration method applied to industrial robots, comprising the following steps:

S1. Keep the end tool of the industrial robot perpendicular to the XOY plane of the base coordinate system, realize the alignment of the end tool of the industrial robot with the precision detection switch of the TCP detection device through the manual teaching method, and record the space pose data of the flange of the industrial robot;

S2. After the industrial robot has been working continuously for a period of time, the industrial robot detects whether the TCP point of the current industrial robot has a large offset according to the spatial pose data of the initial manual teaching. If it cannot meet the production requirements, it enters the calibration procedure;

S3. Calibration program: the calibration controller controls the terminal tool of the industrial robot to perform a calibration movement of a square trajectory in the TCP detection device with an initial posture through the control cabinet; during the movement process, the microcontroller unit of the calibration controller monitors the TCP detection device According to the on-off state of the four groups of through-beam photoelectric sensors, according to the time point of the on-off signal, read and store the flange space pose data of the industrial robot at that time point, and use the space pose data stored above to calculate the industrial robot The position deviation and angle deviation of the end tool in the direction of X-axis and Y-axis, and realize the error compensation of TCP;

S4, repeating the operation of step S3, and reducing the TCP calibration error through the iteration of the calibration results;

S5. Control the end tool to perform uniform linear motion in the Z-axis direction of the base coordinate system to determine the position deviation of the industrial robot TCP in the Z-axis direction and compensate for the error of the TCP;

S6. Repeat the operation of step S5, and reduce the TCP calibration error by iterating the calibration results.

The above-mentioned TCP online rapid calibration method applied to industrial robots is characterized in that the calculation method of the position deviation of the end tool in the X-axis and Y-axis directions in the step S3 is:

During the calibration movement, every time the end tool passes through a group of through-beam photoelectric sensors, the calibration controller reads the space pose data of the flange coordinate system of the industrial robot, which is recorded as P _ijn ;

The i represents the i-th group of through-beam photoelectric sensors, i=1 or 2 or 3 or 4, wherein 1 is the through-beam photoelectric sensor 1, 2 is the through-beam photoelectric sensor 2, and 3 is the through-beam photoelectric sensor 3 , 4 is the through-beam photoelectric sensor 4;

Said j represents the on-off of the through-beam photoelectric sensor, j=1 or 2, 1 means that the through-beam photoelectric sensor signal is connected, and 2 means that the through-beam photoelectric sensor signal is disconnected;

The n represents the nth pass through the i-th group of through-beam photoelectric sensors in a single cycle movement, n=1 or 2;

Based on the space pose data of the flange coordinate system obtained by the calibration controller,

A. When the end tool passes through the first group of through-beam photoelectric sensors 1 for the first time, the Y-axis coordinates of the intersection point between the center line of the end tool and the laser beam of the through-beam photoelectric sensor 1 are:

${\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 11</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 111</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; Y</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 121</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; Y</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; ,</span>$

When the end tool passes through the third group of through-beam photoelectric sensors 3 for the first time, the Y-axis coordinates of the intersection point between the center line of the end tool and the laser ray of the through-beam photoelectric sensor 3 are:

${\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 31</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 311</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; Y</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 321</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; Y</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; ,</span>$

When the end tool passes through the first group of through-beam photoelectric sensors 1 for the second time, the Y-axis coordinates of the intersection point between the center line of the end tool and the laser ray of the through-beam photoelectric sensor 1 are:

${\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 12</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 112</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; Y</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 122</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; Y</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; ,</span>$

When the end tool passes through the third group of through-beam photoelectric sensors 3 for the second time, the Y-axis coordinates of the intersection point between the center line of the end tool and the laser ray of the through-beam photoelectric sensor 3 are:

${\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 32</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 312</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; Y</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 322</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; Y</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; ,</span>$

Therefore, the position deviation of the TCP of the end tool in the Y-axis direction can be calculated by the following formula:

${\mathrm{<span\; class="notranslate">\; TCP</span>}}_{\mathrm{<span\; class="notranslate">\; \&Delta;</span>}\mathrm{<span\; class="notranslate">\; Y</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 11</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 12</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 31</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 32</span>}}}{\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; ;</span>$

B. When the end tool passes through the second group of through-beam photoelectric sensors 2 for the first time, the X-axis coordinates of the intersection point between the center line of the end tool and the laser ray of the through-beam photoelectric sensor 2 are:

${\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; one</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 211</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 221</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; x</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; ,</span>$

When the end tool passes through the third group of through-beam photoelectric sensors 4 for the first time, the Y-axis coordinates of the intersection of the center line of the end tool and the laser ray of the through-beam photoelectric sensor 4 are:

${\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 41</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 411</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 421</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; x</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; ,</span>$

When the end tool passes through the second group of through-beam photoelectric sensors 2 for the second time, the X-axis coordinates of the intersection of the centerline of the end tool and the laser ray of the through-beam photoelectric sensor 2 are:

${\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; two</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 212</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 222</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; x</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; ,</span>$

When the end tool passes through the third group of through-beam photoelectric sensors 4 for the second time, the Y-axis coordinates of the intersection point between the center line of the end tool and the laser ray of the through-beam photoelectric sensor 4 are:

${\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 42</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 412</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 422</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; x</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; ,</span>$

Therefore, the position deviation of the TCP of the end tool in the X-axis direction is calculated as:

${\mathrm{<span\; class="notranslate">\; TCP</span>}}_{\mathrm{<span\; class="notranslate">\; \&Delta;</span>}\mathrm{<span\; class="notranslate">\; x</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; one</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; two</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 41</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 42</span>}}}{\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; .</span>$

The calculation method of the angular deviation in the above step S3 is:

The distance between the upper and lower layers of opposite-beam photoelectric sensors 1 and 3 is d, and the angle deviation in the Y direction of the end tool is calculated as follows:

${\mathrm{<span\; class="notranslate">\; TCP</span>}}_{\mathrm{<span\; class="notranslate">\; \&Delta;</span>}\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; Y</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; arctan</span>}\frac{\mathrm{<span\; class="notranslate">\; L</span>}}{\mathrm{<span\; class="notranslate">\; d</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; arctan</span>}<span\; class="notranslate">\; (</span>\frac{{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 41</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; one</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 42</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; two</span>}}}{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; d</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span>$

The distance between the upper and lower layers of opposite-beam photoelectric sensors 2 and 4 is d, and the angle deviation in the X direction of the end tool is calculated as follows:

${\mathrm{<span\; class="notranslate">\; TCP</span>}}_{\mathrm{<span\; class="notranslate">\; \&Delta;</span>}\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; x</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; arctan</span>}\frac{\mathrm{<span\; class="notranslate">\; L</span>}}{\mathrm{<span\; class="notranslate">\; d</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; arctan</span>}<span\; class="notranslate">\; (</span>\frac{{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 31</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 11</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 32</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 12</span>}}}{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; d</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; .</span>$

The calculation method of the position deviation of the industrial robot TCP in the Z-axis direction in the above step S5 is:

The calibration controller controls the end tool of the industrial robot to move directly above the intersection of the through-beam photoelectric sensors 1 and 2 through the control cabinet, and moves downward along the Z axis at a constant speed. The through-beam photoelectric sensors 1 and 2 detect the end tool The difference between the pose data at the intersection of the two rays and the initial value P _TCP0 obtained through manual teaching is the deviation of the TCP of the end tool in the Z-axis direction:

TCP _Δz =P _TCP .ZP _TCP0 .Z.

The benefits of the present invention are: a TCP detection device and method applied to a TCP online rapid calibration device of an industrial robot provided by the present invention: 1. It can effectively improve the working accuracy of the industrial robot; 2. It can reduce the downtime and maintenance of the industrial robot 3. Effectively improve the automation of industrial production lines, save manpower and material resources, and reduce costs.

Description of drawings

Fig. 1 is a schematic structural diagram of a TCP online rapid calibration device applied to industrial robots according to the present invention.

FIG. 2 is a schematic structural diagram of a TCP calibration device of the present invention applied to a TCP online rapid calibration device for industrial robots.

Fig. 3 is a schematic structural diagram of a TCP detection device of a TCP online rapid calibration device applied to an industrial robot according to the present invention.

Fig. 4 is a structural schematic diagram of a calibration controller of a TCP online rapid calibration device applied to an industrial robot according to the present invention.

Fig. 5 is a schematic diagram of the movement trajectory of the end tool of a TCP online rapid calibration device applied to an industrial robot according to the present invention.

Fig. 6 is a schematic diagram of measuring the displacement error in the X/Y axis direction by the TCP detection device of a TCP online rapid calibration device applied to an industrial robot according to the present invention.

Fig. 7 is a schematic diagram of measuring angular errors in the X/Y axis direction by a TCP detection device of a TCP online rapid calibration device applied to an industrial robot according to the present invention.

Fig. 8 is a schematic diagram of measuring the displacement error in the Z-axis direction by a TCP detection device of a TCP online rapid calibration device applied to an industrial robot according to the present invention.

FIG. 9 is a flow chart of a TCP online calibration method of a TCP online rapid calibration device applied to an industrial robot according to the present invention.

The meanings of the marks in the accompanying drawings are as follows:

1. Control cabinet, 2. TCP calibration device, 3. Industrial robot, 4. End tool, 5. Control bus;

201. TCP detection device, 202. Installation base, 203. Calibration controller;

301, through-beam photoelectric sensor 1, 302, through-beam photoelectric sensor 2, 303, through-beam photoelectric sensor 3, 304, through-beam photoelectric sensor 4, 305, accuracy inspection switch, 306, upper cover, 307, device Ontology;

401. Device shell, 402. Display unit, 403. Key unit, 404. Status indicator light, 405. Communication interface.

detailed description

The present invention will be described in further detail below in conjunction with the accompanying drawings and embodiments.

As shown in Figure 1: a TCP online rapid calibration device applied to an industrial robot 3, including a control cabinet 1, a TCP calibration device 2, an industrial robot 3, an end tool 4 and a control bus 5, and the control cabinet 1 passes through the control bus 5 respectively Connect the TCP calibration device 2 and the industrial robot 3, and the end tool 4 is installed on the industrial robot 3;

As shown in Figure 2: the TCP calibration device 2 includes a TCP detection device 201, a calibration controller 203 and an installation base 202, the TCP detection device 201 is fixedly installed on one side of the industrial robot 3 through the installation base 202, and the measurement plane is basically the same as the industrial robot 3 The XOY plane of the coordinate system is parallel.

The laser rays of the through-beam photoelectric sensors 1-301 and 3-303 are parallel to the X-axis of the industrial robot 3 base coordinate system. The laser rays of the through-beam photoelectric sensors 2-302 and 4-304 are parallel to the Y-axis of the industrial robot's 3-base coordinate system.

As shown in Figure 3: the TCP detection device 201 includes a device upper cover 306, a device body 307, an accuracy inspection switch 305 and four groups of through-beam photoelectric sensors, the accuracy inspection switch 305 is arranged on the upper surface of the device body 307, and the device The main body 307 is a rectangular parallelepiped with a hollowed out longitudinal direction. Four groups of through-beam photoelectric sensors are arranged on the inner side of the device body 307 respectively. The through-beam photoelectric sensors 1-301 and 3-303 are in the same vertical plane, and the installation distance of the sensors is d. The through-beam photoelectric sensors 2-302 and 4-304 are in the same vertical plane, and the installation distance of the sensors is d. The laser rays of the through-beam photoelectric sensors 3-303 and 4-304 are perpendicular to each other and in the same horizontal plane. The laser rays of the type photoelectric sensors 1-301, 2-302 are also perpendicular to each other and in the same horizontal plane.

As shown in Figure 4, the calibration controller 203 includes a device housing 401, a microcontroller unit, a display unit 402, a key unit 403, a status indicator light 404 and a communication interface 405, and the calibration controller 203 obtains the output of the precision inspection switch 305 The signals and the on-off signals of the four groups of through-beam photoelectric sensors communicate with the control cabinet 1 through the control bus 5 connected to the communication interface 405 , and feed back the working information through the display unit 402 and the status indicator light 404 .

As shown in Figure 9: a TCP online fast calibration method applied to an industrial robot 3, characterized in that it comprises the following steps:

S1. Keep the end tool 4 of the industrial robot 3 perpendicular to the XOY plane of the base coordinate system, realize the alignment of the end tool 4 of the industrial robot 3 with the precision detection switch of the TCP detection device 201 through manual teaching methods, and record the space of the flange of the industrial robot 3 pose data;

S2. After the industrial robot 3 has been working continuously for a period of time, the industrial robot 3 detects whether the current TCP point of the industrial robot 3 has a large offset according to the spatial pose data of the initial manual teaching. If it cannot meet the production requirements, it enters the calibration procedure;

S3. Calibration program: the calibration controller 203 controls the end tool 4 of the industrial robot 3 through the control cabinet 1 to perform a calibration movement of a square trajectory in the TCP detection device 201 with an initial posture; during the motion process, the microcontroller of the calibration controller 203 The unit monitors the on-off status of the four sets of through-beam photoelectric sensors in the TCP detection device 201, reads and stores the flange space pose data of the industrial robot 3 at the time point according to the time point of the on-off signal, and uses the above storage Calculate the position deviation and angle deviation of the end tool 4 of the industrial robot 3 in the X-axis and Y-axis directions based on the space pose data, and realize TCP error compensation;

S4. Repeat the operation of step S3 twice, and reduce the TCP calibration error by iterating the calibration results;

S5. Control the end tool 4 to perform a uniform linear motion in the Z-axis direction of the base coordinate system, so as to determine the position deviation of the industrial robot 3TCP in the Z-axis direction and compensate the error of the TCP;

S6. Repeat the operation of step S5 twice, and reduce the TCP calibration error by iterating the calibration results.

In the above-mentioned TCP online rapid calibration method applied to the industrial robot 3, the calculation method of the position deviation of the end tool 4 in the X-axis and Y-axis directions in step S3 is:

As shown in Figure 5, the end tool 4 performs a calibration movement of a square trajectory in the TCP detection device 201. During the movement, the end tool 4 in the first half of the path keeps its posture unchanged, and the end tool 4 in the second half of the path wraps around the flange. The Z axis of the coordinate system is rotated by 180°.

As shown in FIG. 6 , the calibration controller 203 controls the end tool 4 of the industrial robot 3 to perform a calibration movement of a square trajectory in the TCP detection device 201 at an initial posture through the robot control cabinet 1 . During the calibration movement, the end tool 4 first passes through the through-beam photoelectric sensors 1-301 and 3-303. After passing through a group of through-beam photoelectric sensors, the calibration controller 203 reads the space pose data of the industrial robot 3 flange coordinate system, which is denoted as P _ijn

The i represents the i-th group of through-beam photoelectric sensors, i=1 or 2 or 3 or 4, wherein 1 is the through-beam photoelectric sensor 1-301, 2 is the through-beam photoelectric sensor 2-302, and 3-303 is The through-beam photoelectric sensor 3-303, 4-304 is the through-beam photoelectric sensor 4-304;

Said j represents the on-off of the through-beam photoelectric sensor, j=1 or 2, 1 means that the through-beam photoelectric sensor signal is connected, and 2 means that the through-beam photoelectric sensor signal is disconnected;

The n represents the nth pass through the i-th group of through-beam photoelectric sensors in a single cycle movement, n=1 or 2;

Based on the flange coordinate system space pose data acquired by the calibration controller 203,

A. When the end tool 4 passes through the first group of through-beam photoelectric sensors 1-301 for the first time, the Y-axis coordinates of the intersection point between the center line of the end tool 4 and the laser beam of the through-beam photoelectric sensor 1-301 are:

${\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 11</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 111</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; Y</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 121</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; Y</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; ,</span>$

When the end tool 4 passes through the third group of through-beam photoelectric sensors 3-303 for the first time, the Y-axis coordinates of the intersection of the centerline of the end tool 4 and the laser ray of the through-beam photoelectric sensor 3-303 are:

${\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 31</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 311</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; Y</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 321</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; Y</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; ,</span>$

When the end tool 4 passes through the first group of through-beam photoelectric sensors 1-301 for the second time, the Y-axis coordinates of the intersection of the centerline of the end tool 4 and the laser ray of the through-beam photoelectric sensor 1-301 are:

${\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 12</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 112</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; Y</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 122</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; Y</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; ,</span>$

When the end tool 4 passes through the third group of through-beam photoelectric sensors 3-303 for the second time, the Y-axis coordinates of the intersection point between the centerline of the end tool 4 and the laser beam of the through-beam photoelectric sensor 3-303 are:

${\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 32</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 312</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; Y</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 322</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; Y</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; ,</span>$

Therefore, the position deviation of the TCP of the end tool 4 in the Y-axis direction can be calculated by the following formula:

${\mathrm{<span\; class="notranslate">\; TCP</span>}}_{\mathrm{<span\; class="notranslate">\; \&Delta;</span>}\mathrm{<span\; class="notranslate">\; Y</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 11</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 12</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 31</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 32</span>}}}{\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; ;</span>$

B. When the end tool 4 passes through the second group of through-beam photoelectric sensors 2-302 for the first time, the X-axis coordinates of the intersection of the center line of the end tool 4 and the laser beam of the through-beam photoelectric sensor 2-302 are:

${\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; one</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 211</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 221</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; x</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; ,</span>$

When the end tool 4 passes through the third group of through-beam photoelectric sensors 4-304 for the first time, the Y-axis coordinates of the intersection of the center line of the end tool 4 and the laser beam of the through-beam photoelectric sensor 4-304 are:

${\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 41</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 411</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 421</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; x</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; ,</span>$

When the end tool 4 passes through the second group of through-beam photoelectric sensors 2-302 for the second time, the X-axis coordinates of the intersection of the center line of the end tool 4 and the laser ray of the through-beam photoelectric sensor 2-302 are:

${\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; two</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 212</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 222</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; x</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; ,</span>$

When the end tool 4 passes through the third group of through-beam photoelectric sensors 4-304 for the second time, the Y-axis coordinates of the intersection of the centerline of the end tool 4 and the laser ray of the through-beam photoelectric sensor 4-304 are:

${\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 42</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 412</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 422</span>}}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; x</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; ,</span>$

Therefore, the position deviation of the TCP of the end tool 4 in the X-axis direction is calculated as follows:

${\mathrm{<span\; class="notranslate">\; TCP</span>}}_{\mathrm{<span\; class="notranslate">\; \&Delta;</span>}\mathrm{<span\; class="notranslate">\; x</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; one</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; two</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 41</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 42</span>}}}{\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; .</span>$

The calculation method of the angular deviation in the above step S3 is:

As shown in Figure 7: the distance between the upper and lower layers of opposite-beam photoelectric sensors 1-301 and 3-303 is d, and the angle deviation in the Y direction of the end tool 4 is calculated as follows:

${\mathrm{<span\; class="notranslate">\; TCP</span>}}_{\mathrm{<span\; class="notranslate">\; \&Delta;</span>}\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; Y</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; arctan</span>}\frac{\mathrm{<span\; class="notranslate">\; L</span>}}{\mathrm{<span\; class="notranslate">\; d</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; arctan</span>}<span\; class="notranslate">\; (</span>\frac{{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 41</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; one</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 42</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; twenty\; two</span>}}}{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; d</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span>$

The distance between the upper and lower layers of opposite-beam photoelectric sensors 2-302 and 4-304 is d, and the angle deviation in the X direction of the end tool 4 is calculated as follows:

${\mathrm{<span\; class="notranslate">\; TCP</span>}}_{\mathrm{<span\; class="notranslate">\; \&Delta;</span>}\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; x</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; arctan</span>}\frac{\mathrm{<span\; class="notranslate">\; L</span>}}{\mathrm{<span\; class="notranslate">\; d</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; arctan</span>}<span\; class="notranslate">\; (</span>\frac{{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 31</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 11</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 32</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 12</span>}}}{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; d</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; .</span>$

The calculation method of the position deviation of the industrial robot 3TCP in the Z-axis direction in the above step S5 is:

As shown in Figure 8: the calibration controller 203 controls the end tool 4 of the industrial robot 3 to move directly above the intersection of the through-beam photoelectric sensors 1-301 and 2-302 through the control cabinet 1, and goes straight down along the Z-axis direction at a constant speed Motion, when the through-beam photoelectric sensors 1-301 and 2-302 detect the pose data when the end tool 4 reaches the intersection of the two rays, the difference between the initial value P TCP0 and the initial value P _TCP0 obtained through manual teaching is the value of the end tool 4 The deviation of TCP in the Z-axis direction:

TCP _Δz =P _TCP .ZP _TCP0 .Z.

During the process of the industrial robot 3 executing the task, the robot control cabinet 1 performs deviation compensation on the coordinates of the end tool 4 of the industrial robot 3 .

The basic principles, main features and advantages of the present invention have been shown and described above. Those skilled in the industry should understand that the above-mentioned embodiments do not limit the present invention in any form, and all technical solutions obtained by means of equivalent replacement or equivalent transformation fall within the protection scope of the present invention.

Claims (3)

1. A TCP online rapid calibration device applied to industrial robots, characterized in that it comprises a control cabinet, a TCP calibration device, an industrial robot, an end tool and a control bus, and the control cabinet is connected to a TCP calibration device and an industrial robot respectively by a control bus , the terminal tool is installed on the industrial robot; the TCP calibration device includes a TCP detection device, a calibration controller and a mounting base, the TCP detection device is fixedly installed on one side of the industrial robot through the mounting base, and the measurement plane is in the same position as the base coordinate system of the industrial robot The XOY planes are parallel. 2. A kind of TCP online rapid calibration device applied to industrial robots according to claim 1, characterized in that said TCP detection device includes a device upper cover, a device body, an accuracy inspection switch and four groups of through-beam photoelectric sensors, The accuracy inspection switch is arranged on the upper surface of the device body, the device body is a rectangular parallelepiped with a vertical hollow square, and four groups of through-beam photoelectric sensors are respectively arranged on the longitudinal midline of the inner side of the device body, and the laser beams of the through-beam photoelectric sensors perpendicular to each other and on the same level. 3. A kind of TCP online rapid calibration device applied to industrial robots according to claim 1, characterized in that said calibration controller includes a device housing, a microcontroller unit, a display unit, a key unit, a status indicator light and a communication Interface, the calibration controller obtains the output signal of the precision inspection switch and the on-off signals of four groups of through-beam photoelectric sensors, and performs data communication with the control cabinet through the control bus connected to the communication interface, and feeds back through the display unit and the status indicator light work messages.