CN110978059A - Portable six-axis manipulator calibration device and calibration method thereof - Google Patents
Portable six-axis manipulator calibration device and calibration method thereof Download PDFInfo
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- CN110978059A CN110978059A CN201911342593.9A CN201911342593A CN110978059A CN 110978059 A CN110978059 A CN 110978059A CN 201911342593 A CN201911342593 A CN 201911342593A CN 110978059 A CN110978059 A CN 110978059A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
- B25J—MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
- B25J19/00—Accessories fitted to manipulators, e.g. for monitoring, for viewing; Safety devices combined with or specially adapted for use in connection with manipulators
- B25J19/0095—Means or methods for testing manipulators
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
- B25J—MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
- B25J9/00—Programme-controlled manipulators
- B25J9/16—Programme controls
- B25J9/1628—Programme controls characterised by the control loop
- B25J9/1653—Programme controls characterised by the control loop parameters identification, estimation, stiffness, accuracy, error analysis
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Abstract
The invention discloses a portable six-axis manipulator calibration device, wherein a calibration sensing device is arranged at the end part of a manipulator; the calibration device is provided with a calibration ball device which is fixedly arranged, and the calibration ball is fixedly arranged on the calibration ball device; four or more than four laser displacement sensors are arranged on the calibration sensing device, and coordinate parameters of the calibration sphere center at different positions and postures of the manipulator are obtained through the laser displacement sensors. The invention also discloses a calibration method of the calibration device. By adopting the technical scheme, the determination mode of the teaching points is simple, time-saving and labor-saving; by adopting non-contact measurement, the working range of the laser displacement sensor is large, and the calibration equipment cannot be damaged; the mechanical arm can measure the calibration ball in a larger range of the working space; meanwhile, the laser displacement sensor has a large working distance, so that the calibration ball device is easier to place in the working space of the manipulator.
Description
Technical Field
The invention belongs to the technical field of articulated manipulator calibration equipment. More particularly, the invention relates to a portable six-axis manipulator calibration device, which is applied to calibration of geometric model parameters of a general articulated manipulator. The invention also relates to a calibration method of the calibration device.
Background
Firstly, introduction of related technical development background of mechanical arm calibration:
1. the errors of the manipulator mainly come from two aspects:
first, geometric errors: the mechanical arm is mainly caused by manufacturing and assembling errors existing in the machining and manufacturing process of the mechanical arm, abrasion existing in the later-stage mechanical arm operation process and the like, and the geometric errors are unrelated to the load and the movement of the mechanical arm;
second, non-geometric errors: the method is mainly caused by the deformation of a connecting rod of the manipulator, the yield deformation of joints, the clearance of gears, friction and the like, and non-geometric errors are related to the load and the motion of the manipulator; the errors in the two aspects cause deviation between an actual kinematics model and an ideal kinematics model of the manipulator, and finally cause pose errors at the tail end of the manipulator.
2. The non-geometric errors are variable due to the correlation with the load and the motion of the manipulator, and the error generation mechanism is more complex, so that an error model is generally difficult to determine; the geometric error is irrelevant to the load and the motion of the manipulator and is only relevant to the kinematic parameters and the joint positions of the manipulator, an error model can be established easily, and model parameters can be identified.
3. The geometric model calibration is carried out on the manipulator, the absolute precision of the manipulator can be improved, and the manipulator manufacturer can also be used as a reference for checking the manufacturing quality.
4. The traditional manipulator calibration device mainly comprises two types:
first, a coordinate measuring machine: the method comprises the following steps of calibrating a mechanical arm by using a coordinate measuring machine, wherein the mechanical arm is required to be arranged on a tail end flange of the mechanical arm by means of a specially designed device, the device generally comprises a plurality of markers (such as spheres), and the position or the pose of a marker combination on the device under a coordinate system of the coordinate measuring machine is measured by the coordinate measuring machine; when the manipulator reaches different joint positions, the position or the pose of the marker combination of the end device is obtained by measuring through a coordinate measuring machine, and the kinematic parameters of the manipulator can be calibrated through a set data processing method;
secondly, a laser tracker: the method comprises the steps that a laser tracker is used for calibrating a mechanical arm, target balls need to be installed at the tail end of the mechanical arm by means of the target balls, when the mechanical arm reaches different joint positions, the positions of the target balls under a coordinate system of the laser tracker are obtained through measurement of the laser tracker, certain laser trackers are also provided with pose measurement matching devices, the devices can also be installed at the tail end of the mechanical arm, at the moment, when the mechanical arm is located at different joint positions, the poses of the manipulator tail end matching devices can be measured through the laser trackers, and similarly, kinematic parameters of the mechanical arm can be calibrated through a set data processing method.
5. The prior art has the following disadvantages: the traditional manipulator calibration device can provide a large working space, but the equipment is heavy, expensive, inconvenient to carry and very complex in use method.
Secondly, searching relevant literature conditions in the prior art:
1. chinese patent documents: an industrial robot calibration device (201720566859.8) based on a three-dimensional force sensor, which adopts the technical scheme that: the calibration device comprises a calibration measurement component and a calibration ball component, wherein the calibration measurement component is arranged on a terminal flange of the robot, and the calibration ball component is fixed in a working space of the robot; the calibration ball assembly comprises a fixed base, a connecting piece fixedly arranged at the upper end of the fixed base and a calibration ball structure which is fixedly arranged at the upper end of the connecting piece through a bolt and corresponds to the measurement ball structure. The technical scheme of the method is simple in structure, the operation steps of the calibration method are simple, and the calibration precision is high.
2. Chinese patent documents: a quick positioner (201720526966.8) of end target ball is measured to industrial robot, its technical scheme is: the rapid positioning device comprises a calibration plate and a transition disc, wherein the front surface of the calibration plate is provided with at least three step surfaces, the front surface of the calibration plate is provided with at least 4 positioning holes for mounting a target ball base, and at least 3 positioning holes in all the positioning holes are respectively positioned on the three step surfaces; the transition disc comprises a first connecting part and a second connecting part, the first connecting part is fixedly connected with the calibration plate through a first device connecting and fixing piece, and the second connecting part is fixedly connected with the flange of the robot through a second device connecting and fixing piece. The patent literature considers that the technical scheme can collect multiple groups of data through the combination of different target ball base positioning holes, effectively improves the quality of collected data, is favorable for improving the test precision, and avoids the problem of singular points possibly occurring in the traditional planar calibration plate.
3. Chinese patent documents: a three-dimensional positioning device (201710185981.5) for industrial robot position calibration adopts the technical scheme that: the positioning device comprises a stand column base, a stand column lead screw assembly X shaft assembly, a Y shaft assembly and the like, wherein the X shaft assembly and the Y shaft assembly are respectively fixed on the stand column lead screw assembly and the stand column base, and a red laser emitter and a green laser emitter on a Z shaft linear sliding table module on an X shaft and a Z shaft linear sliding table module on a Y shaft emit laser, so that the coordinate calibration of the designated position of the manipulator is realized. The patent literature considers that compared with the prior art, the technical scheme does not need to add an additional device at the tail end of the manipulator in the positioning process, and has the advantages of visual image, simple operation, low cost and convenient installation.
Thirdly, the problems of the closest prior art:
1. the teaching point is difficult to determine when the manipulator is calibrated, and teaching is complex and laborious. As described in the patent document "an industrial robot calibration device (201720566859.8) based on three-dimensional force sensor": when the teaching point is determined, the measuring ball is required to be in contact with the calibration ball, and because the contact of the two balls is point contact, the specific contact condition of the two balls is difficult to judge;
2. the wear is large in the use process and the service life is short. As described in the patent document "an industrial robot calibration device (201720566859.8) based on three-dimensional force sensor": when the teaching point is determined, the contact between the measuring ball and the calibration ball needs to be ensured, and the manipulator is in a motion state, so that some uncontrollable collision impact exists between the measuring ball and the calibration ball, and certain loss is generated on the service life of calibration equipment;
3. the calibration equipment is not easy to be arranged in the working space of the manipulator. As described in the patent document "an industrial robot calibration device (201720566859.8) based on three-dimensional force sensor": in order to calibrate the kinematic parameters of the robot in a larger range of the working space of the robot and simultaneously measure the calibration balls in a contact mode, support equipment is possibly needed when the calibration balls are arranged, so that the calibration balls can be positioned in different areas of the whole working space of the manipulator;
4. the calibration process is complex and the operation is complex. As described in the patent document "a three-dimensional positioning device (201710185981.5) for industrial robot position calibration": in the process of obtaining the three-dimensional coordinates of the designated position of each robot end, the following steps are required: operating the positioning equipment to calibrate the zero point before the movement of the manipulator, operating the manipulator to move to a certain joint position, and operating the positioning equipment to calibrate the coordinate after the movement of the manipulator, wherein the whole process is too complicated;
5. the calibration equipment has complex system, easy accumulation of errors and poor system reliability. As described in the patent document "a three-dimensional positioning device (201710185981.5) for industrial robot position calibration": the positioning equipment comprises a plurality of motion axes (an X axis, a Y axis and a Z axis), and the irradiation condition of the two laser transmitters to the tail end of the manipulator needs to be judged by controlling the motion of the three axes, so that the errors are easy to accumulate in a multi-axis system.
Disclosure of Invention
The invention provides a portable six-axis manipulator calibration device, and aims to enable the calibration device of a manipulator to be convenient and easy to use.
In order to achieve the purpose, the invention adopts the technical scheme that:
according to the portable six-axis manipulator calibration device, the end part of the manipulator is provided with the calibration sensing device, the calibration device is provided with the calibration ball device, and the calibration ball is fixedly arranged on the calibration ball device; the calibration sensing device is provided with four or more than four laser displacement sensors, and coordinate parameters of the calibration sphere center at different positions and postures of the manipulator are obtained through the laser displacement sensors.
The calibration sensing device is provided with a connecting column and a connecting disc, one end of the connecting column is fixedly connected with a flange at the end part of the manipulator through one connecting flange, and the other end of the connecting column is coaxially and fixedly connected with the connecting disc through the other connecting flange; the laser displacement sensor is fixedly arranged on the connecting disc, and the mounting surface of the laser displacement sensor and the mounting surface of the connecting column on the connecting disc are opposite.
When the number of the laser displacement sensors is four, three of the laser displacement sensors are respectively arranged on the connecting disc through a square fixing plate and are evenly distributed in a trisection manner along the circumferential direction of the connecting disc; a laser displacement sensor is mounted on the connecting disc through an L-shaped fixing plate.
The calibration ball is fixedly arranged on a bottom plate of the calibration ball device through a calibration ball connecting column; the bottom plate is respectively fixed at a plurality of different positions in the working space of the manipulator in the calibration process.
In order to achieve the same purpose as the technical scheme, the invention also provides a calibration method of the portable six-axis manipulator calibration device, which comprises the following steps:
the calibration method sets a unified coordinate system S for calibrating the sensing device; when the manipulator is operated and the laser displacement sensors aim at the calibration ball placed in the working space of the manipulator, three-dimensional coordinate parameters (x, y, z) of the center of the calibration ball under the unified coordinate system S of the calibration ball device are calculated according to the readings of the laser displacement sensors and the known radius r of the calibration ball.
The specific process of the calibration method is as follows:
1. fixedly mounting the calibration sensing device 2 on a flange at the tail end of a manipulator;
2. fixedly mounting the calibration ball device 3 in a working space of a manipulator;
3. operating the manipulator to enable laser beams of a plurality of laser displacement sensors on the calibration sensing device to be capable of being shot on the calibration ball; meanwhile, the calibration ball is ensured to be within the working distance of all the laser displacement sensors; at the moment, the readings of all the laser displacement sensors are recorded, the coordinates of the sphere center of the calibration sphere under the unified coordinate system S are calculated according to the radius r of the calibration sphere, and meanwhile, the joint angle position of the mechanical arm is recorded;
4. keeping the calibration ball device still, operating the mechanical arm again to enable the mechanical arm to be located at other joint positions, enabling laser beams of all laser displacement sensors to be capable of striking the calibration ball, recording readings of all laser displacement sensors at the moment, calculating coordinates of the center of the calibration ball 31 under the unified coordinate system S at the moment, and recording joint angle positions of the mechanical arm at the same time;
5. according to the joint angle position of the manipulator 1 for measuring the calibration sphere center twice and the established manipulator kinematic model, the conversion relation from a manipulator base coordinate system B to a calibration sensing device unified coordinate system S can be established, and the solved calibration sphere center can be converted from the S coordinate system of the calibration sensing device to the coordinate under the manipulator base coordinate system B; because the description of the spherical center coordinates of the calibration spheres measured twice under the manipulator base coordinate system B is unchanged, three coordinate conversion equations can be established;
6. changing the position of the calibration ball device in the working space of the manipulator m times, and repeating the steps 3, 4 and 5 to establish 3m coordinate conversion equations; the model parameters of the manipulator can be calculated by a set data processing method;
the number of times of repeating m is large enough to make 3m larger than the number of model parameters.
By adopting the technical scheme, when the manipulator is calibrated, the method for determining the teaching points is simple, and the teaching is time-saving and labor-saving; due to the adoption of non-contact measurement, the working range of the laser displacement sensors in the calibration device is large, and only the laser beams of 4 laser displacement sensors are required to be irradiated on the calibration ball at the same time, so that the determination of the teaching points is very simple; the calibration device is not damaged due to factors such as too fast movement speed and touch of the manipulator in normal use; the calibration ball device is placed once, and the mechanical arm can measure the calibration ball in a larger range of the working space; meanwhile, the laser displacement sensor has a larger working distance, so that the calibration ball device is easier to place in the working space of the manipulator, and even no support equipment is needed; the whole calibration process is simple to operate, and only the calibration ball device and the operation manipulator are required to be placed, so that the whole operation is simple and convenient.
Drawings
The contents of the drawings and the reference numbers in the drawings are briefly described as follows:
FIG. 1 is a schematic diagram of the general structure of the present invention;
FIG. 2 is a schematic structural diagram of a calibration sensing apparatus according to the present invention;
FIG. 3 is a schematic diagram of the distribution of the laser displacement sensor of the present invention;
FIG. 4 is a schematic view of the calibration ball mounting connection of the present invention.
Labeled as:
1. the mechanical arm 2 is used for calibrating the sensing device 3 is used for calibrating the ball device;
201. the laser displacement sensor comprises a connecting flange, 202, a connecting column, 203, a connecting flange, 204, a connecting disc, 205, a square fixing plate, 206, a square fixing plate, 207, a square fixing plate, 208, an L-shaped fixing plate, 209, a laser displacement sensor, 210, a laser displacement sensor, 211, and 212;
31. calibration balls 32, calibration ball connecting columns 33 and a bottom plate.
Detailed Description
The following detailed description of the embodiments of the present invention will be given in order to provide those skilled in the art with a more complete, accurate and thorough understanding of the inventive concept and technical solutions of the present invention.
First, the structure of the present invention as shown in fig. 1 to 4:
the invention relates to a portable six-axis manipulator calibration device, which solves the problem of the kinematic parameter calibration of a manipulator. And a calibration sensing device 2 is arranged at the end part of the manipulator 1.
In order to overcome the defects of the prior art and achieve the invention purpose of enabling the calibration device of the manipulator to be convenient and easy to use, the invention adopts the technical scheme that:
as shown in fig. 1, the portable six-axis manipulator calibration device of the present invention is provided with a calibration ball device 3, and a calibration ball 31 is fixedly installed on the calibration ball device 3; the calibration sensing device 2 is provided with four or more than four laser displacement sensors, and coordinate parameters of the center of the calibration ball 31 are obtained through the laser displacement sensors when the manipulator 1 is at different positions and postures.
The invention provides a portable and easy-to-use calibration device for the calibration of the manipulator. It mainly comprises: the device comprises a manipulator 1, a calibration sensing device 2 and a calibration ball device 3.
Adopt above-mentioned technical scheme's beneficial effect:
1. during calibration, the determination mode of the teaching point is simple, and teaching is time-saving and labor-saving;
2. due to the adoption of non-contact measurement, the working range of the laser displacement sensors in the calibration device is large, and only the laser beams of 4 laser displacement sensors are required to be irradiated on the calibration ball at the same time, so that the determination of the teaching points is very simple;
3. when the calibration device is normally used, the service life of the calibration device cannot be damaged due to factors such as the excessively high movement speed of the manipulator and the like;
4. the calibration ball device is placed once, and the mechanical arm can measure the calibration ball in a larger range of the working space; meanwhile, the laser displacement sensor has a larger working distance, so that the calibration ball device is easier to place in the working space of the manipulator, and even no support equipment is needed;
5. the whole calibration process is simple to operate, and only the calibration ball device and the operation manipulator are required to be placed, so that the whole operation is simple and convenient.
Secondly, calibrating the sensing device 2 as shown in fig. 2:
the calibration sensing device 2 mainly comprises a connecting flange 201, a connecting column 202, a connecting flange 203, a connecting disc 204, a square fixing plate 205, a square fixing plate 206, a square fixing plate 207, an L-shaped fixing plate 208, a laser displacement sensor 209, a laser displacement sensor 210, a laser displacement sensor 211 and a laser displacement sensor 212.
The connection mode of the constituent structure of the calibration sensing device 2 is as follows:
the calibration sensing device 2 is provided with a connecting column 202 and a connecting disc 204, one end of the connecting column 202 is fixedly connected with a flange at the end part of the manipulator through a connecting flange 201, and the other end of the connecting column 202 is coaxially and fixedly connected with the connecting disc 204 through another connecting flange 203; the laser displacement sensor is fixedly arranged on the connecting disc 204.
The laser displacement sensor is arranged on the surface of the connecting disc 204 facing the calibration ball 31
The calibration sensing device 2 has the following structures and functions:
1. the connecting flange 201: through holes are arranged on the manipulator 1 along the circumferential direction, the manipulator is connected with a flange of the manipulator 1 through bolts, a counter bore is arranged in the center of the connection surface connected with the flange of the manipulator 1, and the manipulator is connected with the connection column 202 through the counter bore;
2. connecting column 202: the upper cylindrical end surface and the lower cylindrical end surface are both provided with bolt holes, the upper end surface is connected with the connecting flange 201 through the bolt holes, and the lower end surface is connected with the connecting flange 203 through the bolt holes;
3. the connecting flange 203: through holes are arranged on the connecting disc 204 along the circumferential direction, the connecting disc 204 is connected with the through holes through bolts, a counter bore is arranged in the center of the connecting surface connected with the connecting disc 204, and the connecting column 202 is connected with the counter bore through the counter bore;
4. a connecting plate 204, the central area of the upper surface of which is provided with a threaded hole along the circumferential direction, is connected with the connecting flange 203 through the threaded hole, 3 disc spokes exist along the circumferential direction, each disc spoke is provided with a through hole, and is connected with a square fixing plate 205, a square fixing plate 206 and a square fixing plate 207 below through the through holes; meanwhile, the area near the center of the connecting disc 204 is also provided with the same through hole, so that an L-shaped fixing plate 208 is connected to the area below the center of the connecting disc through the through hole.
Thirdly, the mounting structure of the laser displacement sensor is shown in fig. 3:
when the number of the laser displacement sensors is four, three of the laser displacement sensors 209, 210 and 211 are respectively installed on the connecting disc 204 through a square fixing plate 205, 206 and 207 and are evenly distributed in trisection along the circumferential direction of the connecting disc 204; a laser displacement sensor 212 is mounted on the interface disc 204 by means of an L-shaped retaining plate 208.
The laser displacement sensor mounting structure and the effect are respectively as follows:
1. square fixing plate: including square fixed plate 205, square fixed plate 206 and square fixed plate 207: the upper side surface of the connecting disc is provided with threaded holes for connecting with three spokes of the connecting disc 204, and the main surface of the connecting disc is provided with through holes for respectively connecting with a laser displacement sensor 209, a laser displacement sensor 210 and a laser displacement sensor 211;
2. l-shaped fixing plate 208: a threaded hole is formed in a side plate of the laser displacement sensor and used for being connected with the connecting disc 204, and a through hole is formed in a main plate of the laser displacement sensor and used for being connected with the laser displacement sensor 212;
3. a laser displacement sensor: including laser displacement sensor 209, laser displacement sensor 210, laser displacement sensor 211 and laser displacement sensor 212, its side has two screw holes that are used for fixing, wherein laser displacement sensor 209, laser displacement sensor 210 and laser displacement sensor 211 are used for being connected with square fixed plate 205, square fixed plate 206 and square fixed plate 207 respectively, and laser displacement sensor 212 is connected with L shape fixed plate 208.
Fourthly, the calibration ball device is shown in figure 4:
the calibration ball device 3 mainly comprises three parts: calibration balls 31, a calibration ball connection post 32 and a bottom plate 33. The calibration ball 31 is fixedly arranged on a bottom plate 33 of the calibration ball device 3 through a calibration ball connecting column 32; the base plates 33 are fixed at a plurality of different positions in the working space of the manipulator during the calibration process.
The structure and the effect of the calibration ball device are respectively as follows:
1. calibration ball 31: the surface of the calibration ball 31 has certain sphericity and surface roughness, the radius r is known, and a threaded hole is arranged below the calibration ball for connecting with the calibration ball connecting column 32;
2. calibration ball connecting post 32: the upper thread of the calibration ball connecting column 32 is used for being connected with a calibration ball, the lower thread of the calibration ball connecting column is used for being connected with the bottom plate 33, and a conical surface is arranged at the joint of the upper thread and the main body part of the calibration ball connecting column for transition;
3. bottom plate 33: the center of the bottom plate 33 is provided with a threaded hole for connecting the calibration ball connecting column 32, and in addition, four corners of the bottom plate 33 are provided with unthreaded holes for fixing the whole calibration ball device.
The invention relates to a calibration method of a portable six-axis manipulator calibration device, which adopts the technical scheme that (taking four laser displacement sensors as an example):
after the calibration sensing device 2 is assembled and fixed, the relationship between the default coordinate systems of the four laser displacement sensors can be calibrated.
Setting a unified coordinate system S of the calibration sensing device 2; when the manipulator 1 is operated to aim the four laser displacement sensors at the calibration sphere 31 placed in the working space of the manipulator 1, the three-dimensional position (x, y, z) of the centre of the calibration sphere in the unified coordinate system S of the calibration sphere device 2 can be calculated according to the readings of the 4 laser displacement sensors (d1, d2, d3, d4) and the known radius r of the calibration sphere 31.
The unified coordinate system S may be set at a default coordinate system of any one of the 4 laser displacement sensors, or may be set at any other position.
The specific process of the calibration method is as follows:
1. fixedly mounting the calibration sensing device 2 on a flange at the tail end of a manipulator;
2. fixedly installing the calibration ball device 3 in a working space of the manipulator 1;
3. operating the manipulator 1 to enable laser beams of four laser displacement sensors on the calibration sensing device 2 to strike the calibration ball 31; meanwhile, the calibration ball 31 is ensured to be within the working distance of the four laser displacement sensors at the same time; at the moment, the readings of the four laser displacement sensors are recorded (d1, d2, d3 and d4), the coordinates of the sphere center of the calibration sphere in the unified coordinate system S are calculated according to the radius r of the calibration sphere 31, and the joint angle positions of the manipulator are recorded (a1, a2, a3, a4, a5 and a 6);
4. keeping the calibration ball device 3 still, operating the manipulator 1 again to enable the manipulator to be located at other joint positions, enabling laser beams of the four laser displacement sensors to strike the calibration ball 31, recording the readings of the four laser displacement sensors at the moment, calculating the coordinates of the center of the calibration ball 31 under the unified coordinate system S at the moment, and recording the joint angle position of the manipulator 1;
5. according to the joint angle position of the manipulator 1 for measuring the spherical center of the calibration ball 31 twice and the established manipulator kinematic model, the conversion relation from a manipulator base coordinate system B to a unified coordinate system S of the calibration sensing device 2 can be established, and the solved spherical center coordinate of the calibration ball 31 can be converted from the S coordinate system of the calibration sensing device 2 to the coordinate under the manipulator base coordinate system B; because the description of the spherical center coordinates of the calibration ball 1 measured twice under the manipulator base coordinate system B is unchanged, three coordinate conversion equations can be established;
6. changing the position of the calibration ball device 3 in the working space of the manipulator 1 m times, and repeating the steps 3, 4 and 5 to establish 3m coordinate conversion equations; the model parameters of the manipulator 1 can be calculated by a set data processing method;
the number of times of repeating m is large enough to make 3m larger than the number of model parameters.
Sixthly, comparative analysis of the invention and the prior art publications:
1. with respect to prior art documents: an industrial robot calibration device (201720566859.8) based on a three-dimensional force sensor; the invention is different from the method for acquiring the local three-dimensional position of the auxiliary calibration object, and the applied sensor is different.
The technical document is that a local three-dimensional coordinate of an auxiliary calibration object is obtained based on a three-dimensional force sensor, a calibration ball is touched by a measurement ball, and a three-dimensional coordinate of the center of the calibration ball under a local coordinate system of the measurement ball is calculated according to a three-dimensional force signal obtained by detection; according to the invention, the three-dimensional coordinates of the center of the calibration sphere under the unified coordinate system of the laser displacement sensors are calculated by means of 4 laser displacement sensors according to the distance readings of the 4 laser displacement sensors.
In the technical literature, a contact method is adopted for detecting the three-dimensional coordinates of the center of the calibration sphere; the invention adopts a non-contact method for detecting the three-dimensional coordinates of the center of the calibration ball.
2. With respect to prior art documents: an industrial robot measuring end target ball quick positioning device (201720526966.8); the technical literature is mainly used for fixing target balls of the laser tracker and is matched with laser tracker equipment for use so as to realize the calibration of a manipulator; the invention is a complete set of calibration equipment for calibrating the kinematic parameters of the manipulator.
3. With respect to prior art documents: a three-dimensional positioning device (201710185981.5) for industrial robot position calibration; the technical document explicitly calculates the three-dimensional position of the designated position of the tail end of the manipulator in an external measurement coordinate system through the motion of two laser transmitters in the positioning device and the X axis, the Y axis and the Z axis; the three-dimensional position of the designated position (the sphere center of the calibration sphere) in the external coordinate system is not explicitly calculated, and only a constraint equation about the three-dimensional position is established.
The calibration precision of the technical document mainly depends on the moving precision of each axis (X axis, Y axis and Z axis) of the positioning device; the calibration accuracy of the invention mainly depends on the accuracy of the laser displacement sensor.
Seventhly, summarizing the technical innovation points and the technical key points of the invention:
1. the three-dimensional coordinates of the center of the fixed calibration ball are determined by adopting 4 laser displacement sensors, the minimum number of the center of the calibration ball is determined by adopting 4 laser displacement sensors, and compared with measuring equipment such as a laser tracker, a coordinate measuring machine and the like, the system is simple, low in cost, strong in portability and convenient to install;
2. the three-dimensional coordinates of the center of the fixed calibration ball are determined by adopting 4 laser displacement sensors, the mode of determining the calibration teaching points is simpler, only the laser beams of the 4 laser displacement sensors are required to be simultaneously hit on the calibration ball, the teaching is simple, and the operation is convenient;
3. the specifications of the 4 laser displacement sensors are variable, the radius r of the calibration ball 1 is variable, and the laser displacement sensors with different working distances and the calibration balls with different radii can be configured aiming at the mechanical arms with different working spaces, so that the calibration equipment can be used on the mechanical arms with different types, namely the calibration equipment is wide in application range and strong in expandability.
Eighth, more specific embodiment of the present invention:
1. in the invention, 4 laser displacement sensors are adopted in the calibration sensing device 2 to measure the three-dimensional position of the calibration ball 31, which is the minimum number of required laser displacement sensors, so that the configuration of more than 4 laser displacement sensors can also be applied to the invention and higher measurement precision can be provided; furthermore, if the sensor in the calibration sensing device 2 can directly obtain the surface point cloud of the calibration sphere, the method can also be directly applied to the invention, such as a surface structured light sensor, a TOF camera, and the like;
2. the installation positions of 4 laser displacement sensors in the calibration sensing device 2 are adjustable so as to adapt to calibration balls with different radiuses; for example, for a calibration ball with a smaller radius, the installation positions of the 4 laser displacement sensors can be adjusted to enable the included angle between the laser beams emitted by the 4 laser displacement sensors to be smaller, so that the calibration teaching points can be determined more conveniently; of course, for a calibration ball with a larger radius, the included angle between the light beams of the 4 laser displacement sensors can be adjusted to be larger;
3. the connecting flange 201 in the calibration sensing device 2 can be provided with a plurality of circumferential through hole configurations so as to meet the installation requirements of flanges at the tail ends of different manipulators;
4. the precision of 4 laser displacement sensors in the calibration sensing device 2 can be selected from different specifications to adapt to different calibration precision requirements;
5. working distances of 4 laser displacement sensors in the calibration sensing device 2 can also be selected to be different in specification so as to adapt to different working intervals of different manipulators;
6. the calibration ball 31 in the calibration ball device 3 can adopt different radii, and the sphericity, the roughness and the like of the spherical surface can be configured with different specifications to meet different calibration precision requirements.
The invention has been described above with reference to the accompanying drawings, it is obvious that the invention is not limited to the specific implementation in the above-described manner, and it is within the scope of the invention to apply the inventive concept and solution to other applications without substantial modification.
Claims (7)
1. The utility model provides a six portable manipulator calibration device, manipulator (1) tip set up and mark sensing device (2), its characterized in that: the calibration device is provided with a calibration ball device (3), and a calibration ball (31) is fixedly arranged on the calibration ball device (3); the calibration sensing device (2) is provided with four or more than four laser displacement sensors, and coordinate parameters of the sphere center of the calibration sphere (31) at different positions and postures of the manipulator (1) are obtained through the laser displacement sensors.
2. The portable six-axis robot calibration device according to claim 1, wherein: the calibration sensing device (2) is provided with a connecting column (202) and a connecting disc (204), one end of the connecting column (202) is fixedly connected with a flange at the end part of the manipulator through a connecting flange (201), and the other end of the connecting column (202) is coaxially and fixedly connected with the connecting disc (204) through another connecting flange (203); the laser displacement sensor is arranged on the surface of the connecting disc (204) facing the calibration ball (31).
3. The portable six-axis robot calibration device according to claim 2, wherein: when the number of the laser displacement sensors is four, three laser displacement sensors (209, 210 and 211) are respectively arranged on the connecting disc (204) through a square fixing plate (205, 206 and 207) and are evenly distributed in trisection along the circumferential direction of the connecting disc (204); a laser displacement sensor (212) is mounted on the connecting plate (204) by an L-shaped fixing plate (208).
4. The portable six-axis robot calibration device according to claim 1, wherein: the calibration ball (31) is fixedly arranged on a bottom plate (33) of the calibration ball device (3) through a calibration ball connecting column (32); the bottom plate (33) is respectively fixed on a plurality of different positions in the working space of the manipulator in the calibration process.
5. The calibration method of the portable six-axis robot calibration device according to any one of claims 1 to 4, wherein: the calibration method sets a unified coordinate system S for calibrating the sensing device (2); when the manipulator (1) is operated and the laser displacement sensors aim at the calibration ball (31) placed in the working space of the manipulator (1), three-dimensional coordinate parameters of the center of the calibration ball (31) under the unified coordinate system S of the calibration ball device (2) are calculated according to the readings of the laser displacement sensors and the known radius of the calibration ball (31).
6. The calibration method of the portable six-axis robot calibration device according to claim 5, wherein: the specific process of the calibration method is as follows:
1) fixedly mounting the calibration sensing device (2) on a flange at the tail end of the manipulator;
2) the calibration ball device (3) is fixedly arranged in the working space of the manipulator (1);
3) the manipulator (1) is operated, so that laser beams of a plurality of laser displacement sensors on the calibration sensing device (2) can all be shot on the calibration ball (31); meanwhile, the calibration ball (31) is ensured to be within the working distance of all the laser displacement sensors; at the moment, reading numbers of all the laser displacement sensors are recorded, coordinates of the sphere center of the calibration sphere (31) under a unified coordinate system S are calculated according to the radius of the calibration sphere (31), and meanwhile, the joint angle position of the manipulator (1) is recorded;
4) keeping the calibration ball device (3) still, operating the mechanical arm (1) again to enable the mechanical arm (1) to be located at other joint positions, enabling laser beams of all laser displacement sensors to strike the calibration ball (31) in the same way, recording readings of all the laser displacement sensors at the moment, calculating coordinates of the center of the calibration ball (31) at the moment under a unified coordinate system S, and recording joint angle positions of the mechanical arm (1) at the same time;
5) according to the joint angle position of the manipulator (1) for measuring the sphere center of the calibration ball (31) twice and the established manipulator kinematic model, the conversion relation from a manipulator base coordinate system B to a unified coordinate system S of the calibration sensing device (2) can be established, and the calculated sphere center of the calibration ball (31) can be converted from the S coordinate system of the calibration sensing device (2) to the coordinate under the manipulator base coordinate system B; because the description of the center coordinates of the calibration ball (1) measured twice under the manipulator base coordinate system B is unchanged, three coordinate conversion equations can be established;
6) changing the position of the calibration ball device (3) in the working space of the manipulator (1) m times, and repeating the step 3), the step 4) and the step 5), so that 3m coordinate conversion equations can be established; the model parameters of the manipulator (1) can be calculated by a set data processing method.
7. The calibration method of the portable six-axis manipulator calibration device according to claim 6, wherein: the number of times of repeating m is large enough to make 3m larger than the number of model parameters.
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112361958A (en) * | 2020-11-04 | 2021-02-12 | 同济大学 | Line laser and mechanical arm calibration method |
| CN112720470A (en) * | 2020-12-18 | 2021-04-30 | 南京中科煜宸激光技术有限公司 | Mechanical arm TCP manual rapid calibration device and method for additive machining |
| CN112936341A (en) * | 2021-02-01 | 2021-06-11 | 威海威高骨科手术机器人有限公司 | Reset platform assembly process and calibration method |
| CN113084798A (en) * | 2021-03-16 | 2021-07-09 | 浙江大学湖州研究院 | Robot calibration device based on multi-station measurement |
| CN113510708A (en) * | 2021-07-28 | 2021-10-19 | 南京航空航天大学 | Contact industrial robot automatic calibration system based on binocular vision |
| CN113548443A (en) * | 2020-04-23 | 2021-10-26 | 上海微电子装备（集团）股份有限公司 | Detection method and detection device for manipulator handover |
| CN113878586A (en) * | 2021-11-04 | 2022-01-04 | 上海景吾智能科技有限公司 | Robot kinematics calibration device, method and system |
| CN114043087A (en) * | 2021-12-03 | 2022-02-15 | 厦门大学 | Three-dimensional trajectory laser welding seam tracking attitude planning method |
| CN114536324A (en) * | 2022-01-11 | 2022-05-27 | 重庆智能机器人研究院 | Workpiece calibration method for automatic tool of industrial robot |
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BE1010211A6 (en) * | 1996-05-14 | 1998-03-03 | Den Bossche Johan Van | Method for programming a robot by means of external coordinate measuring system and manual probe |
| CN105058387A (en) * | 2015-07-17 | 2015-11-18 | 北京航空航天大学 | Industrial robot base coordinate system calibration method based on laser tracker |
| CN107042527A (en) * | 2017-05-20 | 2017-08-15 | 天津大学 | A kind of industrial robot caliberating device and scaling method based on three-dimensional force sensor |
| CN107560538A (en) * | 2017-08-17 | 2018-01-09 | 安徽零点精密机械有限责任公司 | The scaling method of six-DOF robot tool coordinates system based on laser tracker |
| CN107738254A (en) * | 2017-08-25 | 2018-02-27 | 中国科学院光电研究院 | The conversion scaling method and system of a kind of mechanical arm coordinate system |
| US20190099887A1 (en) * | 2017-09-29 | 2019-04-04 | Industrial Technology Research Institute | System and method for calibrating tool center point of robot |
| CN109676636A (en) * | 2019-03-06 | 2019-04-26 | 南京航空航天大学 | A kind of industrial robot kinematics calibration system and scaling method |
-
2019
- 2019-12-23 CN CN201911342593.9A patent/CN110978059B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BE1010211A6 (en) * | 1996-05-14 | 1998-03-03 | Den Bossche Johan Van | Method for programming a robot by means of external coordinate measuring system and manual probe |
| CN105058387A (en) * | 2015-07-17 | 2015-11-18 | 北京航空航天大学 | Industrial robot base coordinate system calibration method based on laser tracker |
| CN107042527A (en) * | 2017-05-20 | 2017-08-15 | 天津大学 | A kind of industrial robot caliberating device and scaling method based on three-dimensional force sensor |
| CN107560538A (en) * | 2017-08-17 | 2018-01-09 | 安徽零点精密机械有限责任公司 | The scaling method of six-DOF robot tool coordinates system based on laser tracker |
| CN107738254A (en) * | 2017-08-25 | 2018-02-27 | 中国科学院光电研究院 | The conversion scaling method and system of a kind of mechanical arm coordinate system |
| US20190099887A1 (en) * | 2017-09-29 | 2019-04-04 | Industrial Technology Research Institute | System and method for calibrating tool center point of robot |
| CN109571546A (en) * | 2017-09-29 | 2019-04-05 | 财团法人工业技术研究院 | Robot tool center point correction system and method thereof |
| CN109676636A (en) * | 2019-03-06 | 2019-04-26 | 南京航空航天大学 | A kind of industrial robot kinematics calibration system and scaling method |
Non-Patent Citations (4)
| Title |
|---|
| 向民志等: "激光跟踪仪与机器人坐标系转换方法研究", 《航空制造技术》 * |
| 徐艳华等: "基于激光测距传感器的机械臂运动学参数标定", 《激光杂志》 * |
| 王胜华等: "机器人定点变位姿手-眼标定方法", 《清华大学学报(自然科学版)》 * |
| 袁康正等: "机器人末端位移传感器的安装位置标定方法", 《浙江大学学报(工学版)》 * |
Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113548443B (en) * | 2020-04-23 | 2022-03-25 | 上海微电子装备（集团）股份有限公司 | Detection method and detection device for manipulator handover |
| CN113548443A (en) * | 2020-04-23 | 2021-10-26 | 上海微电子装备（集团）股份有限公司 | Detection method and detection device for manipulator handover |
| CN112361958A (en) * | 2020-11-04 | 2021-02-12 | 同济大学 | Line laser and mechanical arm calibration method |
| CN112361958B (en) * | 2020-11-04 | 2022-06-21 | 同济大学 | Line laser and mechanical arm calibration method |
| CN112720470A (en) * | 2020-12-18 | 2021-04-30 | 南京中科煜宸激光技术有限公司 | Mechanical arm TCP manual rapid calibration device and method for additive machining |
| CN112720470B (en) * | 2020-12-18 | 2022-05-13 | 南京中科煜宸激光技术有限公司 | Mechanical arm TCP manual rapid calibration device and method for additive machining |
| CN112936341A (en) * | 2021-02-01 | 2021-06-11 | 威海威高骨科手术机器人有限公司 | Reset platform assembly process and calibration method |
| CN113084798A (en) * | 2021-03-16 | 2021-07-09 | 浙江大学湖州研究院 | Robot calibration device based on multi-station measurement |
| CN113510708A (en) * | 2021-07-28 | 2021-10-19 | 南京航空航天大学 | Contact industrial robot automatic calibration system based on binocular vision |
| CN113878586A (en) * | 2021-11-04 | 2022-01-04 | 上海景吾智能科技有限公司 | Robot kinematics calibration device, method and system |
| CN114043087A (en) * | 2021-12-03 | 2022-02-15 | 厦门大学 | Three-dimensional trajectory laser welding seam tracking attitude planning method |
| CN114536324A (en) * | 2022-01-11 | 2022-05-27 | 重庆智能机器人研究院 | Workpiece calibration method for automatic tool of industrial robot |
| CN114536324B (en) * | 2022-01-11 | 2023-11-07 | 重庆智能机器人研究院 | Industrial robot automatic tool workpiece calibration method |
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