CN110355788B - Large-scale space high-precision online calibration system of mobile operation robot - Google Patents
Large-scale space high-precision online calibration system of mobile operation robot Download PDFInfo
- Publication number
- CN110355788B CN110355788B CN201910673549.XA CN201910673549A CN110355788B CN 110355788 B CN110355788 B CN 110355788B CN 201910673549 A CN201910673549 A CN 201910673549A CN 110355788 B CN110355788 B CN 110355788B
- Authority
- CN
- China
- Prior art keywords
- calibration
- mobile
- robot
- measuring
- mechanical arm
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000005259 measurement Methods 0.000 claims abstract description 42
- 238000004891 communication Methods 0.000 claims abstract description 18
- 239000012636 effector Substances 0.000 claims description 29
- 230000000007 visual effect Effects 0.000 claims description 12
- 238000001514 detection method Methods 0.000 claims description 8
- 239000000919 ceramic Substances 0.000 description 10
- 238000012545 processing Methods 0.000 description 7
- 238000000034 method Methods 0.000 description 6
- 230000000694 effects Effects 0.000 description 4
- 230000036544 posture Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 238000009826 distribution Methods 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- 229910000831 Steel Inorganic materials 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 238000004364 calculation method Methods 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 239000000284 extract Substances 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 238000003801 milling Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000007480 spreading Effects 0.000 description 1
- 238000003892 spreading Methods 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 238000011179 visual inspection Methods 0.000 description 1
Classifications
-
- 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
-
- 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
-
- 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
- B25J9/1694—Programme controls characterised by use of sensors other than normal servo-feedback from position, speed or acceleration sensors, perception control, multi-sensor controlled systems, sensor fusion
Landscapes
- Engineering & Computer Science (AREA)
- Robotics (AREA)
- Mechanical Engineering (AREA)
- Manipulator (AREA)
- Length Measuring Devices By Optical Means (AREA)
Abstract
The invention relates to a large-size space high-precision online calibration system of a mobile operation robot, which comprises a calibration compensation subsystem and a calibration subsystem. The measuring subsystem comprises a multi-view measuring device with a view field covering the working space of the mobile operation robot, at least one group of local measuring devices and a vehicle-mounted laser micrometer device arranged on the mobile platform, and the calibration compensation subsystem comprises a mobile operation robot controller, a communication module connected with the measuring subsystem and a calibration workstation. The multi-view measuring device comprises an infrared camera, an image acquisition workstation connected with the infrared camera and a reflective target ball associated with the mobile platform. Each local measurement device includes a CCD camera and a plurality of laser ranging sensors. Compared with the calibration and the calibration of the traditional mobile robot, the scheme of the invention has the advantages of full automation, large space and online calibration; meanwhile, the operation flexibility is improved, the cost is reduced, and the practical value of the mobile operation robot system is effectively improved.
Description
Technical Field
The invention relates to the technical field of robots, in particular to a large-scale space high-precision online calibration system of a mobile operation robot.
Background
The processing and measuring of large and complex structural members, such as aerospace structural members, high-speed railway car body structural members and the like, generally have the requirements of high precision and high surface quality, and depend on large processing equipment such as a gantry machine tool, a large milling machine and the like, and the processing equipment is needed for the part to be processed. Therefore, this not only results in very high input costs for the processing equipment, but also, if the characteristics of the processed parts change, or the size increases, the original equipment may not meet new requirements, resulting in high input risk of equipment, and meanwhile, the flexible requirements during practical application cannot be met.
Therefore, the mobile operation robot system formed by combining the industrial robot and the mobile robot is a feasible scheme facing the processing of large and complex structural parts, has higher dexterity and extremely large working space, and can effectively improve the working efficiency through the cooperative operation of the multi-mobile operation robot system.
However, a key problem encountered with mobile handling robotic systems is the wide range of high precision positioning. The current solutions all measure the robot end directly or indirectly and ensure the absolute accuracy of the robot end in a large working space by a robot motion control mode, and the solutions all need to be completed by means of high-cost iGPS, laser tracker and other devices. Furthermore, this requires that the end of the operating arm of the mobile operating robot must be tracked and measured in real time. Therefore, when the number of mobile operation robots is increased, or the number of the iGPS or the laser trackers is blocked by a complicated processing environment, the number of the iGPS or the laser trackers must be increased, which not only results in a significant increase in cost, but also greatly reduces the flexibility of application thereof. At present, although a small amount of such application appears in the field of aerospace processing, manufacturing and measurement, the popularization and application of the application are greatly limited by the high price and the low flexibility of the application.
In summary, calibration of the traditional fixed industrial robot is often implemented in a small indoor space, the measurement range of the used precise measuring instrument is generally below a few meters, and high-precision measurement can be realized by combining a precise mechanical structure and an optical principle; the traditional mobile operation robot has a large free working space, but is limited by centimeter-level positioning precision. Based on the above, it is necessary to provide an online calibration system capable of realizing large-space and high-precision on-line of a mobile operation robot, so that real-time tracking and measuring of the terminal pose of the robot is not required to ensure the precision. The calibration system meeting the requirements can not only greatly improve flexibility, but also reduce cost, and effectively improve the practical value of the mobile operation robot system.
Disclosure of Invention
The invention provides a high-precision online calibration scheme of a mobile robot applicable to a large-scale space, which aims to solve the technical problems.
The technical scheme of the invention is that the on-line calibration system of the mobile operation robot comprises a sub-system and a calibration compensation sub-system. The measuring subsystem comprises a multi-view measuring device, at least one group of local measuring devices and a vehicle-mounted laser micrometer device, wherein the visual field of the multi-view measuring device covers the working space of the mobile operation robot, the vehicle-mounted laser micrometer device is arranged on the mobile platform, and the calibration compensation subsystem comprises a mobile operation robot controller, a communication module and a calibration workstation, wherein the communication module is connected with the measuring subsystem. The multi-view measuring device comprises an infrared camera, an image acquisition workstation connected with the infrared camera and a reflective target ball associated with the mobile platform. Each of the local measuring devices comprises a CCD camera and a plurality of laser ranging sensors.
According to some aspects of the invention, an array of infrared cameras of different perspectives is arranged over the workspace of the mobile manipulator robot; the image acquisition workstation is in communication connection with each infrared camera; and a plurality of reflective target balls are arranged at the corners of the mobile platform.
According to some aspects of the invention, the plurality of laser ranging sensors are distributed around the CCD camera in a space triangle under the support of the clamp; the shooting direction of the CCD camera faces to the movement area of the mobile operation robot.
According to some aspects of the present invention, the external accessory device of the local measurement device further comprises an equilateral triangle target, a support fixture and a linear motion device, wherein the equilateral triangle target is mounted at the tail end of a mechanical arm of the mobile operation robot, and the local measurement device is fixed on a motion table of the linear motion device through the support fixture, so that the linear motion device can drive the local measurement device to perform linear motion with controlled distance.
According to some aspects of the invention, the linear motion device comprises a linear motor, a guide rail for guiding the motion table to linearly move, a grating sensor and a motion driver connected with the linear motor and the grating sensor.
According to some aspects of the invention, the on-board laser micrometer apparatus comprises a biaxial outer diameter micrometer fixedly mounted on the mobile platform by a mounting support; the working part of the double-shaft outer diameter micrometer is plate-shaped, a laser measuring area is reserved in the middle of the working part, and the working part is used for detecting the outer diameter of a rod-shaped object inserted into the laser measuring area and providing a measuring basis for the pose calibration of an end effector of an operating arm with rod-shaped characteristics.
According to some aspects of the invention, the tail end of the mechanical arm is provided with equilateral triangular blocks serving as targets, the vertexes of the equilateral triangular blocks are respectively provided with target balls, and the center positions of the equilateral triangular blocks are provided with visual detection marks.
According to some aspects of the invention, the mobile manipulator robot controller includes an industrial motion controller, a memory, and a motion control program for the mobile manipulator robot.
According to some aspects of the invention, the calibration workstation is connected to the mobile operation robot controller by utilizing the communication module, controls the mechanical arm to move to a measurement pose, receives the in-place information of the mechanical arm and collects the angle data of each joint of the mechanical arm, and is also connected to each electrical device of the measurement subsystem by utilizing the communication module so as to receive the data of the measurement subsystem and control the measurement subsystem; and the calibration workstation stores a mechanical arm kinematic error model, acquires nominal geometric parameters from the mechanical arm controller, respectively calibrates the mechanical arm body base coordinate parameters, geometric parameters and end effector bias parameters at the operation position based on the real values obtained by the measurement subsystem, generates a new motion track and compensates the motion controller.
According to some aspects of the invention, the laser ranging sensor is pre-calibrated by an off-line calibration device comprising a laser tracker, one or more target balls associated with the laser tracker and disposed at the end of the mechanical arm, a rod connected to the target balls, and a laser tracker auxiliary measuring means Tmac.
The technical scheme of the invention also relates to a method for calibrating the large-scale space of the mobile operation robot with high precision, which comprises the following steps:
s1, arranging a global reference network of a large-scale space under a world coordinate system of a field space, and deploying multi-view measuring equipment for coarse measurement and a plurality of local measuring equipment for fine measurement based on the global reference network;
S2, after the mobile platform of the mobile operation robot stops at a preset operation position, performing coarse positioning on the mobile platform by utilizing multi-view measuring equipment, and controlling the tail end of the mechanical arm of the mobile operation robot with the homemade target to enter the measuring range of the local measuring equipment by taking the mechanical arm base coordinate system under the coarse positioning as a reference;
S3, in a precise measurement range, guiding a target at the tail end of the mechanical arm to move to a position through local visual recognition, so that the target is successfully hit by measurement laser, calculating the tail end pose of the mechanical arm according to a multi-laser ranging principle and target geometric information, then changing the tail end pose of the mechanical arm for a plurality of times, measuring and recording the changed tail end pose value, and calibrating the coordinate system deviation and the kinematic geometric parameter error of the mechanical arm base;
s4, recalculating the planned pose of the end effector of the mechanical arm based on the pose errors of the mechanical arm body and the base obtained by calculation, and compensating the errors of the end effector of the robot through a compensation algorithm;
s5, building a vehicle-mounted laser micrometer system on the mobile platform, and performing pose measurement on the columnar reference by using the vehicle-mounted laser micrometer system to calibrate the bias parameters of the end effector of the mechanical arm on line.
The beneficial effects of the invention are as follows:
Compared with the calibration and calibration of the traditional fixed and mobile robots, the online calibration scheme with global coarse precision and local high precision has the advantages of full automation, large space and online calibration; in addition, the calibration scheme of the invention also improves the operation flexibility, reduces the cost and effectively improves the practical value of the mobile operation robot system.
Drawings
FIG. 1 is a schematic diagram of a global vision measurement subsystem and an online calibration system.
Fig. 2 is a schematic view of a rail-based mobile partial visual guide apparatus.
Fig. 3 is a schematic diagram of a mobile manipulator robot on-board dual-axis laser micrometer measurement.
Fig. 4 is a global reference dot example schematic.
Fig. 5 is an enlarged detail view of the end target of fig. 4.
FIG. 6 is a flow chart of an on-line calibration system implementation.
FIG. 7 is a calibration compensation flow chart for a calibration workstation.
FIG. 8 is a diagram showing the relationship between the components of the on-line calibration system and the calibration implementation flow.
Detailed Description
The conception, specific structure, and technical effects produced by the present application will be clearly and completely described below with reference to the embodiments and the drawings to fully understand the objects, aspects, and effects of the present application. It should be noted that, without conflict, the embodiments of the present application and features of the embodiments may be combined with each other.
It should be noted that, unless otherwise specified, when a feature is referred to as being "fixed" or "connected" to another feature, it may be directly or indirectly fixed or connected to the other feature. Further, the descriptions of the upper, lower, left, right, etc. used in the present invention are merely with respect to the mutual positional relationship of the constituent elements of the present invention in the drawings. As used in this specification and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.
It should be understood that although the terms first, second, third, etc. may be used in this disclosure to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element of the same type from another. For example, a first element could also be termed a second element, and, similarly, a second element could also be termed a first element, without departing from the scope of the present disclosure.
The term "large-sized space" as used herein refers to a space that is several times larger than the size of a conventional fixed or mobile robot itself. Generally, it is understood that a space of at least 10m x 10m is considered, but in various practical applications, a "large-sized space" may be considered and defined comprehensively according to factors such as a machined part, a robot movement range, and the like. The invention refers to high precision, which is higher than the machining precision and the motion precision of the prior art in various application occasions, so as to obtain better technical effects and improvements.
Referring to fig. 1-3, a calibration system according to the present invention includes a set of measurement subsystems and a set of calibration compensation subsystems.
The measurement subsystem is used to make visual measurements of the mobile platform 110 coordinate system, the pose of the robot end 113, and the pose offset of the robot end effector.
The measurement subsystem includes: spatially distributed multi-view measuring devices, local measuring devices 120, and on-board laser micrometer devices.
The multi-view measuring apparatus includes: an infrared camera 116, an image acquisition workstation 130 connected to the infrared camera 116, and a reflective target ball associated with the mobile manipulator robot 109.
The infrared camera 116 is disposed in an upper space where the mobile manipulation robot 109 operates. A plurality of infrared cameras 116 can be fixedly installed through distribution type by using supports such as steel materials, aluminum materials and the like and a cross beam. The measurement fields of view of the plurality of infrared cameras 116 can cover a large scale space, such as a space covering at least 10 meters by 10 meters.
The image acquisition workstation 130 establishes communication connection with each camera, controls the cameras to synchronously acquire the image information of the mobile platform 110, extracts characteristic points of the images and fuses the image data with the multi-camera data, and obtains positioning information of the mobile platform 110 to be delivered to the calibration workstation 127.
The reflective target balls are mounted at four corners of the robot mobile platform 110, so that the camera can position the mobile platform 110 in space.
The local measuring device 120 and its external accessory devices may be provided in a work area of the robot arm 111 of the mobile manipulator robot 109.
The external accessory includes a linear motion device having high-precision linear motion characteristics. The linear motion device comprises a linear motor, a guide rail, a grating sensor, a driver and the like.
The local measuring device 120 is fixed to the motion stage of the linear motion apparatus by the support jig 102 so that the linear motion apparatus can drive the local measuring device 120 to perform a fine linear motion of which the distance is controlled.
The local measuring device 120 comprises a plurality of (preferably 9) laser ranging sensors 121 and a CCD camera 122. The CCD camera 122 is used to guide the robot arm tip 113 target into the measurable area of the laser ranging sensor 121 and is thus mounted in the center position of the jig. The plurality of laser ranging sensors 121 may be divided into 3 groups, and distributed around the CCD camera 122 in a spatial triangle (e.g., 120 ° interval) on the jig. Each group of lasers can determine the space position of the center of one target ball in the target of the tail end 113 of the mechanical arm, and is used for further calculating the position and the posture information of the center point of the equilateral target;
the equilateral triangle target 123 is mounted on the arm end 113 of the mobile manipulator robot 109. A high-precision reflective target ball is respectively arranged at the top of the triangular target 123, and a visual detection mark 128 is stuck at the center of the triangular block. The reflective target ball is, for example, a ceramic target ball with a smooth surface, or a polished target ball made of other metal materials.
The in-vehicle laser micrometer apparatus includes a mounting support and a dual-axis outside diameter micrometer 125 that is mounted and secured to the moving platform 110 of the robot. The working part of the double-shaft outer diameter micrometer is plate-shaped, a laser measuring area is reserved in the middle of the working part, and the working part is used for detecting the outer diameter of a rod-shaped object inserted into the laser measuring area and providing a measuring basis for the pose calibration of an end effector of an operating arm with rod-shaped characteristics.
The calibration compensation subsystem includes: a mobile manipulator robot controller 129, a communication module and a calibration workstation 127.
The mobile manipulator robot controller 129 is used for controlling the motion of the body of the mechanical arm 111 and the mobile platform 110, and the geometric nominal parameters of the motion of the mechanical arm 111 are stored in the controller. The mobile manipulator robot controller 129 includes an industrial motion controller (e.g., PLC, motion control card), a driver of the mobile manipulator robot 109, and the like.
The communication module is used for communication among the controller, the field bus, the switch and various devices, and can comprise a gateway, the switch, a data repeater of various protocols, a wireless network card and the like.
Calibration workstation 127: the communication module is connected to the mobile operation robot controller 129 to control the mechanical arm 111 and the mobile platform 110 to move to a measuring pose, receive the in-place information of the mechanical arm 111 and collect the angle data of each joint of the mechanical arm 111; each electrical device (including image acquisition workstation 130) connected to the measurement subsystem with a communication module, receives measurement subsystem data and can exercise control over the measurement subsystem; by establishing a mechanical arm 111 kinematic error model, calculating mechanical arm 111 motion geometric nominal parameters from mechanical structures of the mechanical arm 111, calibrating mechanical arm 111 body base coordinate parameters, geometric parameters and end effector bias parameters at the operation position respectively based on the real values obtained by the measurement subsystem, generating new motion tracks and compensating a controller.
Some embodiments of the calibration operation flow of the calibration system according to the invention will be described below with reference to fig. 6 to 8, through 5 main steps. As shown in fig. 8, step S1 involves the construction of each hardware platform of the calibration system and the off-line calibration of the corresponding ranging sensor. Steps S2 to S5 involve the online calibration system gradually advancing from the low-precision calibration of the 110 cm level of the mobile platform to the high-precision calibration of the 111 micron level of the mechanical arm, and further achieving the micron-level high-precision calibration of the tool at the end 113 of the mechanical arm. In some application scenarios, each sensing device of the online calibration system according to the present invention needs to be calibrated offline once, and then the processes of steps S2 to S5 can be repeated in real time during the working process of the mobile operation robot 109, and the pose and calibration tool of the robot can be updated online. Step S2 is mainly implemented by the infrared camera 116 of the multi-view measuring device and the vehicle-mounted reflective target ball on the mobile operation robot 109; the guiding step S3.1 in step S3 is performed by the visual detection mark 128 provided by the CCD camera 122 and the robot tip 113 of the local measuring device 120, and the subsequent measuring step S3.2 is performed by the targets and targets mounted by the laser ranging sensor 121 and the robot tip 113 of the local measuring device 120; step S4 may be performed by an external computing device, or may be performed directly or indirectly by a motion controller of the mobile manipulator robot 109; step S5 is mainly performed by moving the dual axis micrometer sensor on the on-board platform of the manipulator robot 109.
The individual steps are described below by way of detailed examples.
Step S1
The global reference network of the large-scale space is built to solve the problem of error accumulation caused by multiple interconversions of the reference coordinate system of the measuring equipment in the manufacturing site of the large-scale industrial robot. The distribution of the net points of the global reference net is related to the measurement distance and precision of the sensors in the space, space shielding and other factors.
The pose information of the sensor in the space is directly or indirectly measured at the reference lattice point by using non-contact, large-range and high-convenience standard measuring equipment such as the laser tracker 101, the laser tracker 101 is moved to the next reference lattice point aiming at the sensor equipment outside the measurable space, the pose information of a part of the last lattice point sensor can be measured at the reference lattice point, and the transformation information of the lattice point relative to the last lattice point is calculated. In order to reduce accumulated errors among the net points, the method of spreading from the center net point to the periphery is adopted for construction, and finally, pose information of the sensor in the space relative to a unified world coordinate system is established by using a splicing method.
In one example, as in fig. 4 and 5, the laser tracker 101 is built with (e.g., the Leica company's product) as a fiducial point while calibrating the pose of a certain laser ranging sensor 121 and a certain infrared camera 116 in the fiducial point. The support jig 102 is mounted on the arm end 113, and is mounted with: (1) A minute diameter (e.g., 1 mm) high precision ceramic target ball 124 for reflecting the laser light of the laser ranging sensor 121; (2) The auxiliary measuring device Tmac of the laser tracker can directly feed back the 6-DOF position and posture information; (3) a set of retroreflective target spheres 105 for infrared camera 116 identification. The reflective target balls are connected by a high-precision rod member 106.
Controlling the mechanical arm 111 to move to the first position 107, so that the ceramic target ball 124 is aligned with the laser line of the laser ranging sensor 121, and capturing and converting the laser line into the pose of the ceramic target ball 124 at the position through the laser tracker 101; the robot 111 is controlled to move to the second position 108, and the ceramic target ball 124 is aligned with the laser line of the laser ranging sensor 121, so that the pose of the ceramic target ball 124 can be obtained. The direction of the laser entering the laser ranging sensor 121 can be obtained through the pose of the two points of the ceramic target ball 124, the distance information can be measured through the laser ranging sensor 121, and finally the pose information of the laser ranging sensor 121 at the datum point can be obtained. Similarly, the infrared camera 116 can also obtain its pose relative to the reference point by measuring the reflective target ball set 105 twice.
Step S2
To reduce the probability of obstruction of the space, as shown in fig. 1, an infrared camera 116 vision measurement subsystem is mounted by using a bracket 115 composed of a support such as steel, aluminum and a beam. The reflective target ball 117 is installed at four corners of the mobile platform 110, and when the mobile manipulator robot 109 and the mobile platform 110 move within a measurable range of the infrared camera 116, the infrared camera 116 recognizes the reflective target ball 117 and further calculates and determines the spatial position of the mobile platform 110 according to the geometric distribution of the reflective target ball.
As a result of the spatial deployment of multiple infrared cameras 116. The mobile platform 110 may be captured simultaneously by multiple infrared cameras 116, utilizing redundant positioning data generated by multiple cameras and optimized with a data fusion algorithm.
Then, since the mechanical arm base 112 and the mobile platform 110 are rigidly connected through the vehicle body, the conversion relationship between them can be determined through off-line calibration in factory shipment; thus, under the condition that the pose information of the mobile platform 110 is obtained through the above measurement, the pose information of the robot arm base 112 with respect to the world coordinate system can be obtained. However, the accuracy of visual measurement in a large space is limited, and the positioning of the manipulator base 112 is only a preliminary positioning, which provides a reference for the next step of controlling the movement of the manipulator end 113 to a local high-accuracy measurement area under the world coordinate system.
Step S3
As shown in fig. 2, an equilateral triangular block 123 is precisely machined, three high-precision ceramic target balls 124 are respectively mounted at the vertexes of the triangular block 123, a visual detection mark 128 (for example, mark point mark) is stuck at the center position of the triangular block 123, and the equilateral triangular block 123 is mounted as a target on a flange of the end 113 of the mechanical arm (or on the end flange through an extension rod). The 9 laser ranging sensors 121 and the CCD camera 122 (e.g., CCD guide camera) are combined into one local measuring device 120, which is mounted on the support jig 102 movable with the precision linear guide 118. To correspond to the targets 123 of the equilateral triangle, the 9 laser ranging sensors 121 are divided into 3 groups, each occupying one corner of the spatial triangle, and the CCD camera 122 is mounted at the center of the spatial triangle.
In the local high-precision local measurement area where the target 123 of the mechanical arm terminal 113 moves, at this time, the visual detection mark 128 attached to the target 123 enters the field of view of the guiding CCD camera 122, and the mechanical arm terminal 113 is guided to a certain pose by the visual detection mark 128, and under the pose, 3 laser beams of each group of laser ranging sensors 121 can hit the corresponding target ball 124 in the equilateral triangle target 123. At this time, the robot arm 111 is suspended, and the calibration workstation 127 records the ranging data of the respective laser ranging sensors 121 via the communication module, and captures the respective joint values of the robot arm 111 via the mobile operation robot controller 129. According to trilateration, each group of lasers can determine the spatial position of the center of one target sphere 124, and through geometric calculation, the position and posture information of the center point of the equilateral triangular block 123 can be calculated. The CCD camera 122 is utilized to track the mark pose, on the premise that 3 groups of lasers can hit respective target balls, the pose of the tail end 113 of the mechanical arm is changed for many times, the measurement result is recorded, and the deviation and the kinematic geometric parameter error of the coordinate system of the base 112 of the mechanical arm relative to the world coordinate system are obtained through the calibration algorithm of the calibration workstation 127.
In view of the free movement of the mobile manipulator within the working space of a large space, to ensure that at least one local measuring device 120 beside each working point performs high-precision measurement on the manipulator end 113, and to save the number of deployments of the local measuring devices 120, the segmented high-precision mobile rail 118 is used to carry the local measuring devices 120 to move into the operable range of the manipulator 111. In order to improve the quality of parameter calibration of the robot 111, at least two local measuring devices 120 are ensured, and a certain spatial distance is kept between the two local measuring devices 120, and the pose of the robot 111 is changed enough to "excite" as many kinematic parameters to be calibrated as possible in the mathematical operation process.
Step S4
Generally, to ensure the efficiency and accuracy of robot programming, the robot's work tasks and positioning programs must be planned and generated by an offline programming system, with the robot programmed by specifying the absolute pose of the end effector center point (TCP) in the world coordinate system. The calibration of the base coordinate system parameters and the geometric parameters of the manipulator 111 at the working site is performed based on steps S2-S3, respectively, and the calibration of the end effector bias parameters requires that the manipulator 111 body is accurate after the calibration and compensation of the geometric parameters of the manipulator 111.
As shown in fig. 7, since not every robot 111 can allow direct modification of the kinematic parameters file, it is more desirable to compensate the robot 111 by modifying the end effector pose. The base coordinate system of the mechanical arm 111 is firstly compensated into the pose of the mechanical arm end effector after offline programming, the compensated pose is subjected to kinematic inverse solution by using real geometric parameters to obtain each joint value, and then the joint values are subjected to kinematic correct solution by using nominal geometric parameters (or geometric parameters calibrated last time) to obtain new pose values of the end effector. The compensation of the end effector bias is also to compensate for the pose value of the end effector.
By communication between the calibration workstation 127 and the mobile manipulator robot controller 129, controller instructions are modified to complete the compensation based on the pose value of the new end effector.
Step S5
As shown in fig. 3, an on-board dual-axis laser micrometer 125 is built on the mobile platform 110, and after the geometric parameters of the robotic arm 111 are calibrated, if the end effector has a cone-shaped or stick-shaped geometric feature. The mechanical arm end effector is controlled to be vertically inserted into the center plane of the biaxial laser micrometer 125, the position point of the biaxial laser micrometer 125, where the light receiving elements crossing two directions are blocked, is recorded, and is used as the reference position of the end effector bias, and the bias of the end effector pose at the reference position is zero. After the mechanical arm end effector works for a period of time, whether the relation between the end effector and the mechanical arm end 113 is changed is detected, the end effector is moved to be inserted into the center plane according to the originally set movement instruction again, at this time, the bias of the end effector will be represented as the change of the position point where the light receiving element in the laser micrometer 125 is blocked, and at this time, the end effector needs to be calibrated.
The end effector with offset is inserted into the center detection surface of the biaxial laser micrometer 125 for a plurality of times in different postures, the waiting calibration workstation 127 records the position points where the light receiving elements in two directions are blocked each time the end effector is inserted into the center surface, captures the joint angle of the mechanical arm 111 at the moment, and calculates the offset value of the relation of the end effector relative to the mechanical arm end 113.
The present invention is not limited to the above embodiments, but can be modified, equivalent, improved, etc. by the same means to achieve the technical effects of the present invention, which are included in the spirit and principle of the present disclosure. Are intended to fall within the scope of the present invention. Various modifications and variations are possible in the technical solution and/or in the embodiments within the scope of the invention.
List of reference numerals description
101 Laser tracker
102 Support clamp
103 Micro-diameter high-precision ceramic target ball
104 Laser tracker auxiliary measuring device Tmac and 105 reflecting target ball group
106 Rod piece
107 First position
108 Second position
109 Mobile operation robot
110 Mobile platform
111 Mechanical arm
112 Mechanical arm base
113 Mechanical arm end
115 Support
116 Infrared camera
117 Infrared reflecting target ball
118 Linear motion guide rail
119 Support clamp
120 Local measuring device
121 Laser ranging sensor
122 CCD camera
123 Equilateral triangle target
124 Ceramic target ball
125 Biax laser micrometer
126 Mechanical arm control cabinet
127 Calibration workstation
128 Visual inspection markers
129 Mobile operation robot controller
130 Image acquisition workstation.
Claims (8)
1. A high-precision online calibration system for a large-scale space of a mobile operation robot (109) comprises a measurement subsystem and a calibration compensation subsystem, wherein the mobile operation robot (109) comprises a mobile platform (110) and a mechanical arm (111),
The system is characterized in that the measuring subsystem comprises a multi-view measuring device with a view field covering the working space of the mobile operation robot (109), at least one group of local measuring devices (120) and a vehicle-mounted laser micrometer device arranged on the mobile platform (110), and the calibration compensation subsystem comprises a mobile operation robot controller (129), a communication module connected with the measuring subsystem and a calibration workstation (127), wherein:
the multi-view measuring device comprises an infrared camera (116), an image acquisition workstation (130) connected with the infrared camera (116) and a reflective target ball associated with the mobile platform (110);
each of said local measuring devices (120) comprises a CCD camera (122) and a plurality of laser ranging sensors (121);
The mobile operation robot controller (129) comprises an industrial motion controller, a memory and a motion control program of the mobile operation robot (109);
The calibration workstation (127) is connected to the mobile operation robot controller (129) through a communication module, controls the mechanical arm (111) to move to a measurement pose, receives in-place information of the mechanical arm (111) and acquires angle data of each joint of the mechanical arm (111), and is also connected to each electrical device of the measurement subsystem through the communication module so as to receive the data of the measurement subsystem and control the measurement subsystem;
And the calibration workstation (127) stores a kinematic error model of the mechanical arm (111), acquires nominal geometric parameters from a mechanical arm (111) controller, respectively calibrates the base coordinate parameters, geometric parameters and bias parameters of the end effector of the mechanical arm (111) body at the operation position based on the real values obtained by the measurement subsystem, generates a new motion track and compensates the motion controller.
2. The online calibration system of claim 1, wherein:
Arranging an array of infrared cameras (116) of different perspectives over a workspace of said mobile manipulator robot (109);
The image acquisition workstation (130) establishes communication connection with each infrared camera (116);
a plurality of the reflective target balls are mounted at corners of the moving platform (110).
3. The online calibration system of claim 1, wherein:
the plurality of laser ranging sensors (121) are distributed around the CCD camera (122) in a space triangle under the support of the clamp;
the shooting direction of the CCD camera (122) faces the movement area of the mobile operation robot (109).
4. An on-line calibration system according to claim 1 or 3, characterized in that the external attachment device of the local measuring device (120) further comprises an equilateral triangle target (123), a support jig (102) and a linear motion device, wherein the equilateral triangle target (123) is mounted on the arm end (113) of the mobile manipulator robot (109), and the local measuring device (120) is fixed to the motion stage of the linear motion device through the support jig (102) so that the linear motion device can drive the local measuring device (120) to perform a distance-controlled linear motion.
5. The on-line calibration system according to claim 4, wherein the linear motion device comprises a linear motor, a guide rail for guiding the linear motion of the motion stage, a grating sensor, and a motion driver connected to the linear motor and the grating sensor.
6. The online calibration system of claim 1, wherein:
The vehicle-mounted laser micrometer device comprises a double-shaft outer diameter micrometer (125) fixedly mounted on the mobile platform (110) through a mounting support piece;
The working part of the double-shaft outer diameter micrometer (125) is plate-shaped, a laser measuring area is reserved in the middle of the working part, and the working part is used for detecting the outer diameter of a rod-shaped object inserted into the laser measuring area and providing a measuring basis for the pose calibration of an end effector of an operating arm with rod-shaped characteristics.
7. The online calibration system of claim 1 or 6, wherein:
the tail end (113) of the mechanical arm is provided with equilateral triangular blocks serving as targets, the vertexes of the equilateral triangular blocks are respectively provided with target balls, and the center positions of the equilateral triangular blocks are provided with visual detection marks (128).
8. The on-line calibration system according to claim 1, wherein the laser ranging sensor (121) is pre-calibrated by an off-line calibration device comprising a laser tracker (101), and one or more target balls associated with the laser tracker (101) and arranged at the end (113) of the robot arm, a rod (106) connecting the target balls and a laser tracker auxiliary measuring means Tmac (104).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910673549.XA CN110355788B (en) | 2019-07-24 | 2019-07-24 | Large-scale space high-precision online calibration system of mobile operation robot |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910673549.XA CN110355788B (en) | 2019-07-24 | 2019-07-24 | Large-scale space high-precision online calibration system of mobile operation robot |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110355788A CN110355788A (en) | 2019-10-22 |
| CN110355788B true CN110355788B (en) | 2024-05-14 |
Family
ID=68220717
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910673549.XA Active CN110355788B (en) | 2019-07-24 | 2019-07-24 | Large-scale space high-precision online calibration system of mobile operation robot |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110355788B (en) |
Families Citing this family (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111716355A (en) * | 2020-06-16 | 2020-09-29 | 海克斯康制造智能技术(青岛)有限公司 | Robot absolute positioning precision compensation system and method |
| CN112008937A (en) * | 2020-07-28 | 2020-12-01 | 上海发那科机器人有限公司 | System and method for automatically filling foam by robot |
| CN113146613B (en) * | 2021-01-22 | 2022-11-04 | 吉林省计量科学研究院 | Three-dimensional self-calibration device and method for D-H parameters of industrial robot |
| CN112706193B (en) * | 2021-01-27 | 2022-03-01 | 浙江谱麦科技有限公司 | Cleaning robot performance detection system based on dynamic capture camera |
| CN113386052A (en) * | 2021-05-12 | 2021-09-14 | 华南理工大学 | Hull abrasive water jet paint and rust removing equipment and implementation method thereof |
| CN114367993A (en) * | 2021-12-29 | 2022-04-19 | 上海航天设备制造总厂有限公司 | Device, system and method for converting space coordinates and scanning coordinates of complex curved surface |
| CN114359410B (en) * | 2022-01-10 | 2024-04-19 | 杭州巨岩欣成科技有限公司 | Swimming pool drowning prevention multi-camera space fusion method and device, computer equipment and storage medium |
| CN114305705B (en) * | 2022-03-15 | 2022-06-03 | 珠海维尔康生物科技有限公司 | Automatic correcting device and method for position of surgical robot |
| CN116379984B (en) * | 2023-04-03 | 2023-10-03 | 广州橘子电气有限公司 | Industrial robot positioning accuracy calibration method and system |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101799271A (en) * | 2010-04-01 | 2010-08-11 | 哈尔滨工业大学 | Method for obtaining camera calibration point under large viewing field condition |
| CN102208108A (en) * | 2011-04-01 | 2011-10-05 | 哈尔滨工业大学 | Large-field high-precision quick field overall calibration method for camera |
| CN108858124A (en) * | 2018-09-07 | 2018-11-23 | 北京特种机械研究所 | Its method for carrying mechanical arm position is demarcated using AGV location information |
| CN109099883A (en) * | 2018-06-15 | 2018-12-28 | 哈尔滨工业大学 | The big visual field machine vision metrology of high-precision and caliberating device and method |
| CN210819622U (en) * | 2019-07-24 | 2020-06-23 | 哈尔滨工业大学（深圳） | Large-scale space high-precision online calibration system of mobile operation robot |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2012153629A1 (en) * | 2011-05-12 | 2012-11-15 | 株式会社Ihi | Device and method for controlling prediction of motion |
| JP7069105B2 (en) * | 2016-07-08 | 2022-05-17 | マクドナルド デットワイラー アンド アソシエイツ インコーポレーテッド | Systems and methods for automated artificial vision guided dispensing of viscous fluids for caulking and sealing operations |
-
2019
- 2019-07-24 CN CN201910673549.XA patent/CN110355788B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101799271A (en) * | 2010-04-01 | 2010-08-11 | 哈尔滨工业大学 | Method for obtaining camera calibration point under large viewing field condition |
| CN102208108A (en) * | 2011-04-01 | 2011-10-05 | 哈尔滨工业大学 | Large-field high-precision quick field overall calibration method for camera |
| CN109099883A (en) * | 2018-06-15 | 2018-12-28 | 哈尔滨工业大学 | The big visual field machine vision metrology of high-precision and caliberating device and method |
| CN108858124A (en) * | 2018-09-07 | 2018-11-23 | 北京特种机械研究所 | Its method for carrying mechanical arm position is demarcated using AGV location information |
| CN210819622U (en) * | 2019-07-24 | 2020-06-23 | 哈尔滨工业大学（深圳） | Large-scale space high-precision online calibration system of mobile operation robot |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110355788A (en) | 2019-10-22 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110355788B (en) | Large-scale space high-precision online calibration system of mobile operation robot | |
| CN210819622U (en) | Large-scale space high-precision online calibration system of mobile operation robot | |
| US5828566A (en) | Vision assisted fixture construction | |
| CN106247932B (en) | A kind of online error-compensating apparatus of robot based on camera chain and method | |
| CN108871209B (en) | Large-size workpiece moving measurement robot system and method | |
| JP5199452B2 (en) | External system for improving robot accuracy | |
| JP7153085B2 (en) | ROBOT CALIBRATION SYSTEM AND ROBOT CALIBRATION METHOD | |
| JP4021413B2 (en) | Measuring device | |
| CN108827264B (en) | Mobile workbench and its mechanical arm optics target positioning device and localization method | |
| US20050273198A1 (en) | Method and device for controlling manipulators | |
| CN104786226A (en) | Posture and moving track positioning system and method of robot grabbing online workpiece | |
| US20200262080A1 (en) | Comprehensive model-based method for gantry robot calibration via a dual camera vision system | |
| CN111360812B (en) | Industrial robot DH parameter calibration method and calibration device based on camera vision | |
| CN111707189A (en) | Laser displacement sensor light beam direction calibration method based on binocular vision | |
| JPH03213251A (en) | Workpiece position detecting device | |
| Peng et al. | Development of an integrated laser sensors based measurement system for large-scale components automated assembly application | |
| CN113681563A (en) | Assembling method and system based on double cameras | |
| US4851905A (en) | Vision target fixture construction | |
| CN115179323A (en) | Machine end pose measuring device based on telecentric vision constraint and precision improving method | |
| CN112828454B (en) | Two-dimensional galvanometer online plane precision compensation system and compensation method thereof | |
| Jian et al. | On-line precision calibration of mobile manipulators based on the multi-level measurement strategy | |
| JP2014149182A (en) | Method of positioning relative to workpiece | |
| CN114147723B (en) | Automatic lofting robot system and operation method thereof | |
| Liu et al. | An automated method to calibrate industrial robot joint offset using virtual line-based single-point constraint approach | |
| EP3224004B1 (en) | Robotic system comprising a telemetric device with a laser measuring device and a passive video camera |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |