US 12,333,758 B2
Visual feedback controller
Hiroyuki Sekiguchi, Tokyo (JP); and Takeyuki Kawata, Tokyo (JP)
Assigned to MITSUBISHI ELECTRIC CORPORATION, Tokyo (JP)
Appl. No. 17/926,641
Filed by Mitsubishi Electric Corporation, Tokyo (JP)
PCT Filed Jul. 7, 2020, PCT No. PCT/JP2020/026601
§ 371(c)(1), (2) Date Nov. 21, 2022,
PCT Pub. No. WO2022/009318, PCT Pub. Date Jan. 13, 2022.
Prior Publication US 2023/0196614 A1, Jun. 22, 2023
Int. Cl. G06T 7/73 (2017.01); G05B 19/418 (2006.01); G06T 1/00 (2006.01); G06T 1/60 (2006.01)
CPC G06T 7/74 (2017.01) [G05B 19/41875 (2013.01); G06T 1/0014 (2013.01); G06T 1/60 (2013.01); G05B 2219/32368 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A visual feedback controller to control a positioning operation that positions a machine tip at a position of a target object, the visual feedback controller comprising:
a camera to capture an image of the target object and output the captured image as a target object image;
a template image storage to store a template image obtained by capturing an image of the target object in advance;
processing circuitry to use the target object image and the template image to measure an actual position of the target object with subpixel accuracy, which provides a higher accuracy than a size of a pixel in the target object image and the template image, and output the measured actual position as an image processing measurement value;
to generate a drive command signal that is a command for controlling a positioning operation of a machine driver to which the machine tip is connected; and
to compensate an error of the drive command signal using the image processing measurement value such that the machine tip is positioned at the position of the target object, and generate a drive compensation signal; and
the machine driver to change a position of the machine tip relative to the target object on the basis of the drive compensation signal;
wherein
the processing circuitry generates an analysis image obtained by shifting the template image by an amount having a decimal value with respect to one pixel of the template image;
uses the analysis image and the template image to measure an amount of deviation between the analysis image and the template image by using the target object image and the template image to measure an actual position of the target object with the subpixel accuracy, and outputs the amount of deviation as a calculated deviation; and
calculates the image processing accuracy analytical value from an amount of shift of the analysis image with respect to the template image and the calculated deviation.