US-12623354-B2 - Positioning method and positioning device

US12623354B2US 12623354 B2US12623354 B2US 12623354B2US-12623354-B2

Abstract

There are provided a positioning method and a positioning device that can position workpieces by a simple method and configuration. A positioning method includes: gripping at least one of first and second workpieces; obtaining point group data of the at least one gripped workpiece of the first and second workpieces; calculating a translation matrix of shape fitting point group data obtained by adjusting a position of the point group data to reference data in a position adjustment state of the first and second workpieces; calculating an inverse matrix based on the translation matrix; and positioning the first and second workpieces by moving the at least one gripped workpiece of the first and second workpieces based on at least one of the translation matrix and the inverse matrix.

Inventors

Jun Masuda
Tomokazu Uchiyama
Shinji Fujino
Motohiro KAKUREYA
Kohei YAGI
Shinya Hirano
Hitoshi Fujiyama
Kenji Shimizu
Yuji Mori
Hisao HISHIKAWA
Naofumi MATSUSHITA
Shunsuke Tanaka
Yuki Inoue
Fuminori IMAIZUMI
Junya Nakamura

Assignees

AISIN SHIROKI CORPORATION
Tamadic Co., Ltd.
TACT SYSTEM Co., Ltd.

Dates

Publication Date: 20260512
Application Date: 20220722
Priority Date: 20210730

Claims (8)

1 . A positioning method comprising: gripping at least one of first and second workpieces; obtaining point group data of the at least one gripped workpiece of the first and second workpieces, wherein the point group data refers to multiple points on the at least one gripped workpiece; calculating a translation matrix of shape fitting point group data obtained by adjusting a position of the point group data to reference data in a position adjustment state of the first and second workpieces; calculating an inverse matrix based on the translation matrix; and positioning the first and second workpieces by moving the at least one gripped workpiece of the first and second workpieces based on at least one of the translation matrix and the inverse matrix, wherein the method further comprises moving the shape fitting point group data based on the inverse matrix, moving an origin of the reference data together at a time of the movement, and matching moved origins of the first and second workpieces.
2 . The positioning method according to claim 1 , wherein, in the positioning of the first and second workpieces, the first and second workpieces are positioned by giving an origin to the point group data by using the inverse matrix, calculating a movement amount for moving the one origin of the origins of the first workpiece and the second workpiece to the other origin, and moving the at least one gripped workpiece of the first and second workpieces based on the calculated movement amount.
3 . The positioning method according to claim 1 , further comprising obtaining the shape fitting point group data obtained by adjusting the position of the point group data to the reference data including the origin by using a central processing unit configured to calculate a translation matrix.
4 . The positioning method according to claim 1 , wherein, when the position of the point group data is adjusted to the reference data, a necessary number of arbitrary positions on the reference data can be set as a reference, and a priority can be set to each set reference.
5 . The positioning method according to claim 1 , wherein a grip part that grips at least one of the first and second workpieces is configured as an arm robot that includes a plurality of axes, and includes a distal end part provided with a marker that makes it possible to monitor a position coordinate and an angle of the distal end part of the arm robot, and includes a function of correcting an error of a difference between a current position and a target position of the marker at the distal end part of the arm robot by causing the plurality of axes of the arm robot to make multiple micromotions.
6 . The positioning method according to claim 5 , wherein the multiple micromotions include a function that can set coefficient adjustment of a micromotion amount and a number of times of the micromotions.
7 . The positioning method according to claim 1 , wherein one of the first and second workpieces is an upper sash, and the other one of the first and second workpieces is a column sash.
8 . A positioning device comprising: a robotic arm that grips at least one of first and second workpieces; and a central processing unit, wherein the central processing unit is configured to perform operations including: obtaining point group data of the at least one gripped workpiece of the first and second workpieces, wherein the point group data refers to multiple points on the at least one gripped workpiece; calculating a translation matrix of shape fitting point group data obtained by adjusting a position of the point group data to reference data in a position adjustment state of the first and second workpieces; and calculating an inverse matrix based on the translation matrix, wherein the robotic arm positions the first and second workpieces by moving the at least one gripped workpiece of the first and second workpieces based on at least one of the translation matrix and the inverse matrix, and wherein the central processing unit is configured to perform further operations including moving the shape fitting point group data based on the inverse matrix, moving an origin of the reference data together at a time of the movement, and matching moved origins of the first and second workpieces.

Description

CROSS-REFERENCE TO RELATED APPLICATION Field of the Invention The present invention relates to a positioning method and a positioning device. Background of the Invention Conventionally, a technique that welds a workpiece with another workpiece while gripping the workpiece by an arm robot is known. In this case, a dedicated positioning mechanism (including a mold or a jig for positioning) is used to position not only the arm robot but also the workpiece gripped by the arm robot. However, the positioning mechanism needs to be separately provided, and therefore equipment cost is high and a wide equipment installation space is necessary. Moreover, positioning mechanisms the number of which corresponds to the number of car models are necessary, and, therefore when the number of car models is large, the number of times of set-up changes becomes large, and a total set-up change time becomes longer. Furthermore, every time a new car model is launched, a similar problem occurs. JP 5290324 B2 discloses a method for positioning at least one object at a final posture in a space by an industrial robot. This method uses a first industrial robot, a first optical imaging device and at least one second optical imaging device to position the object. The first industrial robot can adjust the object to a predetermined position. The first optimal imaging device is calibrated in a three-dimensional spatial coordinate system, and is positioned at a known first position in a known direction. The second optimal imaging device is calibrated in the three-dimensional spatial coordinate system, and is positioned at a known second position in the known direction. The first optical imaging device includes a first camera, a first driving unit, and a first angle measurement unit. The first camera is optically calibrated to capture an image in a predetermined first field of view. The first driving unit is a component that determines a direction of the first camera to adjust a position of the first field of view. The first angle measurement unit detects an angular direction of the first camera, and is calibrated in the spatial coordinate system for finding the first field of view in the spatial coordinate system. The second optical imaging device includes a second camera, a second driving unit, and a second angle measurement unit. The second camera is optically calibrated to capture an image in a predetermined second field of view. The second driving unit is a component that determines a direction of the second camera to adjust a position of the second field of view. The second angle measurement unit detects an angular direction of the second camera, and is calibrated in the spatial coordinate system for finding the second field of view in the spatial coordinate system. SUMMARY OF THE INVENTION However, according to JP 5290324 B2, since devices required to position an object are large-scale (the first optical imaging device (the first camera, the first driving unit and the first angle measurement unit) and the second optical imaging device (the second camera, the second driving unit and the second angle measurement unit)), and it cannot be said that a positioning method of the devices is also simple, there has been a room for improvement. The present invention has been made based on an awareness of the above-described problem, and an object of the present invention is to provide a positioning method and a positioning device that can position workpieces by a simple method and configuration. A positioning method according to the present embodiment includes: gripping at least one of first and second workpieces; obtaining point group data of the at least one gripped workpiece of the first and second workpieces; calculating a translation matrix of shape fitting point group data obtained by adjusting a position of the point group data to reference data in a position adjustment state of the first and second workpieces; calculating an inverse matrix based on the translation matrix; and positioning the first and second workpieces by moving the at least one gripped workpiece of the first and second workpieces based on at least one of the translation matrix and the inverse matrix. The positioning method may further include moving the shape fitting point group data based on the inverse matrix, moving an origin of the reference data together at a time of the movement, and matching moved origins of the first and second workpieces. In the positioning of the first and second workpieces, the first and second workpieces may be positioned by giving an origin to the point group data by using the inverse matrix, calculating a movement amount for moving the one origin of the origins of the first workpiece and the second workpiece to the other origin, and moving the at least one gripped workpiece of the first and second workpieces based on the calculated movement amount. The positioning method may further include obtaining the shape fitting point group data obtain