Robot motion indication light spot position rapid acquisition device based on four PSDs

Abstract

The invention relates to the technical field of joint robot calibration, in particular to a robot motion indication light spot position rapid acquisition device based on four PSDs, and aims to solve the problem that in an existing joint robot calibration device based on the PSDs, it is difficult to adjust a robot to be aligned to the central points of the PSDs. The second PSD is fixed above the first laser reflection structure, the third PSD is fixed below the second laser reflection structure, and the fourth PSD is fixed above the second laser reflection structure. The first laser reflection structure and the second laser reflection structure are fixed to the reference plate, the reference plate is connected with the lower shell through bolts, a power source, a signal processor and a wireless transmitter are fixed in the lower shell, the signal processor and the wireless transmitter are connected with the power source, and the wireless transmitter and the wireless data transmission radio station conduct transmission through wireless communication. And the wireless data radio station is connected with the upper computer. The problem that laser ray constraint must be aligned with the center of the PSD for repeated adjustment is solved, the operation difficulty is reduced, and the calibration efficiency and precision are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of articulated robot calibration, and in particular to a robot motion indication spot position rapid acquisition device based on four position sensitive detectors (PSDs). Background Art

[0002] With the widespread application of articulated robots, the low absolute positioning accuracy has become a key issue restricting the development of articulated robots at home and abroad. As most articulated robot calibration devices are costly, complex to operate, and not easy to carry, robot calibration devices using lasers and photosensitive chips have begun to be studied and developed.

[0003] The Chinese patent publication number is "CN 102825602 A", and the patent name is "A method and device for self-calibration of articulated robots based on PSD". This method uses a pair of V-shaped clamps to constrain the center points of two position sensitive devices (PSDs) to form a closed-loop motion chain, and establishes a set of geometric equations of two virtual constraint lines formed by the reflection of the center point connection line of the two PSDs on the two PSD surfaces. By combining multiple groups of positions, the robot deviation value is iteratively calculated. The shortcomings of this device are: when the robot controls the laser to reach the specified position, the PSD spot signal needs to be continuously feedback-adjusted to achieve the robot control laser incident on one PSD center point and reflected to another PSD center point, that is, the robot controls the laser to aim at two PSD center points at the same time, which is difficult to achieve. Summary of the invention

[0004] In order to solve the problem that it is difficult to adjust the robot to align with the PSD center point in the existing PSD-based articulated robot calibration device, the present invention proposes a robot motion indication spot position rapid acquisition device based on four PSDs.

[0005] The technical solution of the present invention to solve the technical problem is as follows:

[0006] A robot motion indication spot position rapid acquisition device based on four PSDs, the device comprising PSD 1, PSD 2, PSD 3, PSD 4, laser reflection structure 1, laser reflection structure 2, lower shell, reference plate, power supply, signal processor, wireless transmitter, wireless data transmission radio and host computer;

[0007] The PSD 1 is fixed below the laser reflection structure 1, the PSD 2 is fixed above the laser reflection structure 1, the PSD 3 is fixed below the laser reflection structure 2, and the PSD 4 is fixed above the laser reflection structure 2; the laser reflection structure 1 and the laser reflection structure 2 are fixed to a reference plate, the reference plate is connected to the lower shell by bolts, a power supply, a signal processor and a wireless transmitter are fixed inside the lower shell, the signal processor and the wireless transmitter are connected to the power supply, the wireless transmitter and the wireless data transmission radio are transmitted through wireless communication, and the wireless data transmission radio is connected to a host computer.

[0008] Beneficial effects of the present invention:

[0009] This device designs a fast acquisition device for the position of the robot motion indication spot based on four PSDs. In the process of acquiring data, it only needs to ensure that the laser is incident on the effective measurement range of the PSD, which overcomes the problem that the laser line must be repeatedly adjusted to the center of the PSD, reduces the difficulty of operation, and improves the calibration efficiency and accuracy.

[0010] Within the effective measurement range of PSD, the device only needs to change the incident point to obtain multiple sets of different data, which overcomes the problem of the prior art that the position of PSD needs to be changed multiple times to obtain multiple sets of different data, reduces the operation steps, and speeds up the calibration speed;

[0011] The device is designed with a laser reflection structure. When the robot controls the laser, it can quickly align with the two PSD effective areas, speed up the robot calibration speed, and accurately obtain the data information on the PSD, thereby improving the accuracy of the experimental data itself, reducing the errors in subsequent calculations, and improving the calibration accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 middle Figure 1 a is a schematic diagram of the top view of the structure of the device for quickly acquiring the position of the robot motion indication spot based on four PSDs according to the present invention; Figure 1 b is Figure 1 a sectional view in the AA direction;

[0013] Figure 2 It is a front view schematic diagram of the angle relationship between the four PSDs of the present invention;

[0014] Figure 3 It is a top view schematic diagram of the angle relationship between the four PSDs of the present invention;

[0015] Figure 4 A schematic diagram of the optical path relationship formed by two groups of reflective structures irradiated by laser according to the present invention;

[0016] Figure 5 Schematic diagram of the transmission of the four PSD signals of the present invention;

[0017] Among them, 1. PSD 1, 2. PSD 2, 3. PSD 3, 4. PSD 4, 5. Laser reflection structure 1, 6. Laser reflection structure 2, 7. Lower shell, 8. Reference board, 9. Power supply, 10. Signal processor, 11. Wireless transmitter, 12. Wireless data transmission station, 13. Host computer. DETAILED DESCRIPTION

[0018] The present invention will be described in further detail below with reference to the accompanying drawings.

[0019] like Figure 1 a and Figure 1 As shown in b, a robot motion indication spot position rapid acquisition device based on four PSDs includes PSD-1, PSD-2, PSD-3, PSD-4, laser reflection structure-1, laser reflection structure-2, lower shell 7, reference plate 8, power supply 9, signal processor 10, wireless transmitter 11, wireless data transmission station 12 and host computer 13.

[0020] PSD-1 is fixed below the laser reflection structure-5, PSD-2 is fixed above the laser reflection structure-5, PSD-3 is fixed below the laser reflection structure-6, and PSD-4 is fixed above the laser reflection structure-6. The laser reflection structure-5 and the laser reflection structure-6 are fixed to the reference plate 8, and the reference plate 8 is connected to the lower shell 7 by bolts. The lower shell 7 is fixed with a power supply 9, a signal processor 10 and a wireless transmitter 11. The signal processor 10 and the wireless transmitter 11 are connected to the power supply 9, and the wireless transmitter 11 and the wireless data transmission radio 12 are transmitted through wireless communication, and the wireless data transmission radio 12 is connected to the host computer 13.

[0021] The angle relationship between the four PSDs is as follows: Figure 2 As shown, PSD 1 and PSD 2 form a group, PSD 3 and PSD 4 form a group, and the angle between the two PSDs in the same reflection relationship is designed to be α, which is complementary to the laser incident angle, and the center distance between the two PSDs is b; the angle between the two groups of reflection structures is designed to be 2α. Figure 3 As shown, the distance between the two sets of reflective structures is determined by the center distance of PSD-1 and PSD-3 and is set to c, and the distance c is ≥ 100 mm. The laser irradiates the two sets of reflective structures to form an optical path relationship as shown in Figure 4 As shown, in the actual calibration process, the operating robot makes the laser incident on PSD 1 and reflected on PSD 2 to form an incident laser straight line and a reflected laser straight line, and then incident on PSD 3 and reflected on PSD 4 to form another incident laser straight line and a reflected laser straight line. The two reflected light rays are skew lines.

[0022] Four PSD signal transmission Figure 5As shown, after communication is established, when the laser beam is irradiated onto the photosensitive surfaces of PSD 1, PSD 2, PSD 3 and PSD 4 respectively, the PSD chip will convert the optical signal into a weak electrical signal, and the signal processor 10 obtains the electrical signal generated by the PSD chip, and transmits the data information to the wireless data transmission station 12 according to the communication protocol through the wireless transmitter 11, and the wireless data transmission station 12 transmits the received data to the host computer 13.

[0023] The working process of the device of the present invention:

[0024] Step 1: Place the acquisition device in the accessible workspace of the robot, establish communication between the acquisition device and the host computer 13, and fix the laser to the end of the robot.

[0025] Step 2: Operate the robot to make the laser incident on PSD-1 and reflect it on PSD-2. The signal processor 10 obtains the electrical signal generated by the PSD chip, and transmits the data information to the wireless data transmission station 12 through the wireless transmitter 11 according to the communication protocol. The wireless data transmission station 12 transmits the received data to the host computer 13. The host computer 13 collects the coordinate information on PSD-2 and PSD-1 at this time, as well as the joint angle data on the corresponding robot teach pendant at this time; adjust the robot posture, make the laser incident on PSD-1 again and reflect it on PSD-2, repeat this operation n times, and record the coordinate information of PSD-1 and PSD-2 and the joint angle data on the corresponding robot teach pendant each time.

[0026] Step 3: After completing step 2, the operating robot moves the laser to another group of PSDs, and the operating robot incidents the laser onto PSD 3 3 and reflects it onto PSD 4 4, and repeats the operation of step 2 on another group of PSDs. The upper computer 13 records a total of n groups of PSD 3 3 and PSD 4 4 coordinate information and the joint angle data on the corresponding robot's teach pendant.

[0027] Example:

[0028] The laser used in the above is a precision semiconductor pulse laser, and the spot diameter of the laser beam is less than 1mm; the PSD used is DRX-2DPSD-GJD02, with a resolution of 0.002mm, a linear error of 0.1%, and an effective surface of 9mm*9mm square, which can detect the two-dimensional position of the pulse laser beam spot on the PSD surface; the laser and PSD are modulated to reduce background light interference. Figure 2 As shown in the figure, each group of PSD has the same structure. The angle between the upper and lower PSD chips is designed to be α = 25°, the center distance b = 60 mm, and the angle between the two groups of PSD is 2α = 50°. The distance between the two groups of PSD is determined by PSD1 and PSD3. Figure 3As shown in Figure c, the centers of PSD-1 and PSD-3 coincide with each other in the horizontal direction, and the distance between them in the vertical direction is c = 110 mm. Figure 4 As shown, the laser light is incident perpendicularly to the device to the PSD below each group of PSD structures, and can be reflected from the lower PSD to the upper PSD, forming two reflection straight lines on the two groups of PSD as skew lines, and the minimum distance between the straight lines is greater than 100mm. To adjust the laser incident on one group of PSD to another group of PSD, it is only necessary to operate the robot to move in a certain direction without adjusting the terminal posture; the 15 groups of PSD coordinate information and the corresponding robot joint angles collected by each group of PSD structures are recorded by the host computer 13. This embodiment uses this collection device to collect data for the Sino-Swiss robot.

[0029] Step 1: Place the acquisition device in the accessible workspace of the robot, establish communication between the acquisition device and the host computer 13, and fix the laser to the end of the robot;

[0030] Step 2: Operate the robot to make the laser incident on PSD-1 and reflected on PSD-2. The signal processor 10 obtains the electrical signal generated by the PSD chip, and transmits the data information to the wireless data transmission radio 12 through the wireless transmitter 11 according to the communication protocol. The wireless data transmission radio 12 transmits the received data to the host computer 13. The host computer 13 collects the coordinate information on PSD-2 and PSD-1 at this time, as well as the joint angle data on the corresponding robot teaching pendant at this time; adjust the robot posture, make the laser incident on PSD-1 again and reflected on PSD-2, repeat this operation 15 times, and record the coordinate information of PSD-1 and PSD-2 and the joint angle data on the corresponding robot teaching pendant each time;

[0031] Step 3: After completing step 2, the operating robot moves the laser to another group of PSDs, and the operating robot incidents the laser onto PSD 3 3 and reflects it onto PSD 4 4, and repeats the operation of step 2 on another group of PSDs. The upper computer 13 records a total of 15 groups of PSD 3 3 and PSD 4 4 coordinate information and the corresponding joint angle data on the robot's teach pendant.

[0032] The data is shown in Table 1-3:

[0033] Table 1 Four PSD position data

[0034]

[0035] Table 2 The first group of robot joint angle data

[0036]

[0037]

[0038] Table 3 The second group of robot joint angle data

[0039]

Claims

1. A robot motion indication spot position rapid acquisition device based on four PSDs, characterized in that: The device comprises PSD 1 (1), PSD 2 (2), PSD 3 (3), PSD 4 (4), laser reflection structure 1 (5), laser reflection structure 2 (6), lower shell (7), reference plate (8), power supply (9), signal processor (10), wireless transmitter (11), wireless data transmission station (12) and host computer (13); The PSD 1 (1) is fixed below the laser reflection structure 1 (5), the PSD 2 (2) is fixed above the laser reflection structure 1 (5), the PSD 3 (3) is fixed below the laser reflection structure 2 (6), and the PSD 4 (4) is fixed above the laser reflection structure 2 (6); the laser reflection structure 1 (5) and the laser reflection structure 2 (6) are fixed to a reference plate (8), the reference plate (8) is connected to a lower shell (7) by bolts, a power supply (9), a signal processor (10) and a wireless transmitter (11) are fixed inside the lower shell (7), the signal processor (10) and the wireless transmitter (11) are connected to the power supply (9), the wireless transmitter (11) and the wireless data transmission radio (12) are transmitted by wireless communication, and the wireless data transmission radio (12) is connected to a host computer (13).

2. The device for quickly acquiring the position of the robot motion indication spot based on four PSDs according to claim 1 is characterized in that: The angle relationship between the four PSDs is: PSD 1 (1) and PSD 2 (2) are a group, and PSD 3 (3) and PSD 4 (4) are a group. The angle between the two PSDs in the same reflection relationship is designed to be α, which is complementary to the laser incident angle, and the center distance between the two PSDs is b; the angle between the two groups of reflection structures is designed to be 2α, and the position relationship between the four PSDs is determined by the center distance between PSD 1 (1) and PSD 3 (3) and is set to c; the laser irradiates the two groups of reflection structures to form an optical path relationship. In the actual calibration, the robot is operated to make the laser incident on PSD 1 (1) and reflected on PSD 2 (2) to form an incident laser straight line and a reflected laser straight line, and then incident on PSD 3 (3) and reflected on PSD 4 (4) to form another incident laser straight line and a reflected laser straight line. The two reflected rays are non-coplanar straight lines.

3. The robot motion indication spot position rapid acquisition device based on quad PSD according to claim 1 is characterized in that: Working process of the device: Step 1: Place the acquisition device in the accessible workspace of the robot (14), establish communication between the acquisition device and the host computer (13), and fix the laser (16) to the end of the robot (15); Step 2: operate the robot (14) to make the laser incident on PSD 1 (1) and reflected on PSD 2 (2), the signal processor (10) obtains the electrical signal generated by the PSD chip, transmits the data information to the wireless data transmission station (12) according to the communication protocol through the wireless transmitter (11), the wireless data transmission station (12) transmits the received data to the host computer (13), the host computer (13) collects the coordinate information on PSD 1 (1) and PSD 2 (2) at this time, and the joint angle data on the teaching pendant of the corresponding robot (14) at this time; adjust the posture of the robot (14), make the laser incident on PSD 1 (1) again and reflected on PSD 2 (2), repeat this operation (15) times, and record the coordinate information of PSD 1 (1) and PSD 2 (2) and the joint angle data on the teaching pendant of the corresponding robot (14) each time; Step 3: After completing step 2, the operating robot (14) moves the laser (16) to another set of PSDs. The operating robot (14) causes the laser to be incident on PSD three (3) and reflected on PSD four (4). The operation of step 2 is repeated on another set of PSDs. The host computer (13) records a total of 15 sets of PSD three (3) and PSD four (4) coordinate information and the corresponding joint angle data on the robot's teaching pendant.

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