Robot-Calibrated Optical Sensor Array with Auxiliary Reference Marks
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current robot-controlled optical measurement systems for workpieces, such as car bodies, face challenges in achieving high accuracy calibration, which is essential for precise measurements but often results in low accuracy due to inadequate calibration methods.
Innovation Solution
The optical measurement array is designed with reference marks on a spacer or sensor housing, allowing for accurate calibration using a tactile or optical method, and an auxiliary device with a sensor target and reference marks for precise positioning, enabling highly accurate determination of the sensor coordinate system relative to the reference marks.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional calibration methods are used for robot-controlled optical measurement systems, then the calibration process can be performed with standard equipment, but the measurement precision and calibration accuracy are insufficient for high-precision production applications
Solution Approach 1:
The patent introduces an auxiliary device as an intermediary component that bridges the robot arm and the optical sensor. This auxiliary device includes a spacer with reference marks and a sensor target, serving as a mediator that enables precise calibration by providing known geometric references for the optical sensor to measure while being mounted on the robot arm. The intermediary auxiliary device allows the calibration system to achieve high precision without requiring complex calibration equipment.
2Productivity
If multiple separate calibration steps are performed for the robot and optical sensor, then each component can be calibrated independently, but the overall calibration process becomes time-consuming and complex
Solution Approach 1:
The patent merges the calibration of the robot arm and optical sensor into a single integrated process. The auxiliary device combines both the robot mounting interface (spacer with reference marks) and the optical sensor target (sensor target with known geometry) into one component. This allows simultaneous calibration of both components in a single measurement cycle, eliminating the need for separate calibration steps and significantly reducing calibration time while maintaining simplicity.
3Measurement precision
If the optical sensor is mounted directly on the robot arm without a spacer, then the mounting structure is simpler, but the positioning accuracy and reproducibility of the sensor coordinate system are insufficient
Solution Approach 1:
The patent segments the mounting structure by introducing a spacer as a separate component between the robot arm and the optical sensor. The spacer is equipped with reference marks that serve as precise positioning references. This segmentation allows the optical sensor to be mounted with high positioning accuracy and reproducibility, as the spacer provides a stable, precisely manufactured reference structure. The segmentation also facilitates easy assembly and disassembly of the sensor while maintaining positioning accuracy.
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
This approach allows for quick, reproducible, and accurate calibration of the optical measurement array, enhancing measurement precision and reducing errors, thereby improving the accuracy of measurements in production environments.
Implementation Method 1
the reference marks can also consist of retroreflectors, in which case a highly accurate measurement of the position of these reference marks can be realized with the aid of a laser tracker
Implementation Method 2
the position of the sensor target in the sensor coordinate system is determined based on the measurement(s)
Data Source
AI summary
Disclosed is a robot-controlled optical measurement array (1) comprising an optical sensor (2) that is fastened to a spacer (3). Reference marks (22) are provided on the spacer (3) and/or on a sensor (2) housing (2′). Said optical measurement array (1) is calibrated by means of an auxiliary device (13) that is placed on the optical measurement array (1) and is provided with a sensor target (16) which is disposed on the auxiliary device so as to lie within one measurement space (17) of the optical sensor (2) when the optical measurement array (1) and the auxiliary device (13) are in the assembled state. In order to calibrate the optical measurement array (1), measured values of the sensor target (16) are generated with the aid of the sensors (2), said measured values being used for calculating the three-dimensional position of the sensor coordinate system (10) in relation to the sensor target (16). Furthermore, measurements of the three-dimensional positions of the reference marks (22) and the auxiliary device are taken using an additional (stationary) measuring apparatus (21). The three-dimensional position of the sensor coordinate system (10) relative to the reference marks (22) can be determined with great accuracy from a combination of all of said measurements.