Accuracy-Monitoring Path Optimization With Error Suppression in Laser Triangulation On-Machine Measurement

Laser triangulation on-machine measurement (LTOMM) with associated processing technology is an effective way to evaluate freeform surfaces’ quality without removing the workpiece from the machine tool. In this article, an integrated system able to acquire the sensor’s one-dimensional displacements and three-dimensional locations is presented. This system is able to prevent spatial mismatch, and then a demand-oriented LTOMM process is proposed. Different from conventional understanding of the trade-off behavior between accuracy and efficiency, an error management strategy is formed to fulfil the required accuracy by precisely controlling the inclination angle and measurement displacement. To improve efficiency, these parameters are fine-tuned adaptively to the surface characteristics by an accuracy-monitoring path optimization algorithm (AMPOA) developed. The unevenly distributed peak error is suppressed by utilizing a mathematical model to regulate the measurement path without compromising efficiency. A simulation is conducted to substantiate that this method is not only able to improve measurement efficiency but also to suppress the peak error. The algorithm and the model were verified on a freeform turbine blade surface with a required accuracy of 20
μ
m. The efficiency was improved by 42.45%, and the peak error was reduced. This would help both the researchers and industries with a more efficient and reverse-controllable demand-oriented LTOMM approach under the constraint of required accuracy in the future.