Robot Arm Optical Calibration Using Grating Holes and Light Intersection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional calibration methods for robotic arms, particularly tool center point calibration, face accuracy issues due to low installation precision, wear of measuring boards, and aging of return springs, leading to reduced calibration accuracy.
Innovation Solution
A calibration device and method utilizing optical sensing devices with grating holes and image recognition patterns to automatically calculate transfer matrices, allowing the robot arm to align the machine tool with a light intersection point, thereby eliminating manual alignment and enhancing calibration precision and efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If contact calibration devices are used for tool center point calibration, then calibration can be performed, but installation accuracy is low and measuring boards wear easily
Solution Approach 1:
The patent replaces the mechanical contact calibration device with an optical sensing system. The optical sensing device uses light beams and image recognition to detect the tool center point position without physical contact, eliminating wear of measuring boards and mechanical components while improving installation accuracy and calibration reliability
Solution Approach 2:
The patent creates an optical copy of the calibration target using image recognition patterns. Instead of relying on physical contact with a measuring board, the system captures images of the tool and calibration target, processes these visual copies to determine positions, thereby avoiding mechanical wear while maintaining measurement capability
2Measurement precision
If manual alignment is used in calibration process, then calibration can be performed, but calibration speed is slow and productivity is low
Solution Approach 1:
The patent implements an automated calibration system where the robot arm performs self-calibration by automatically capturing images, processing the image data to determine the tool center point position, and adjusting its own parameters without human intervention. This eliminates manual alignment operations while maintaining high precision, thereby significantly improving calibration speed and productivity
Solution Approach 2:
The patent establishes a feedback loop where the optical sensing device continuously monitors the tool position, the system processes the image data to determine deviations from the expected position, and the robot arm automatically adjusts its parameters based on this feedback. This automated feedback mechanism replaces slow manual alignment while achieving high precision and speed
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The method improves the speed, reliability, and cost-effectiveness of the calibration process by automating the alignment of the machine tool, reducing manual intervention and increasing precision through the use of optical sensing devices and grating holes.
Implementation Method 1
The first optical sensing device comprises a first light-emitting unit and a first light-receiving unit, the first light-emitting unit is disposed on one of the sidewalls of the frame and provides a first light, and the first light-receiving unit is disposed on the sidewall of the frame corresponding to the first light-emitting unit and receives the first light
Data Source
AI summary
A calibration device is provided. The calibration device includes a frame, a first optical sensing device, a second optical sensing device and a third optical sensing device. The frame includes a bottom plate and at least four sidewalls, wherein the sidewalls have a first grating hole, a second grating hole, a third grating hole and a fourth grating hole at a first height. The bottom plate has an image recognition pattern, a first measurement point, a second measurement point and a third measurement point.