Development of a camera pose estimation algorithm for vibration analysis of an eye-in-hand flexible structure
Journal
Proceedings of SPIE - The International Society for Optical Engineering
Journal Volume
13436
Start Page
1343611
ISSN
0277786X
ISBN (of the container)
9781510686588
Date Issued
2025
Author(s)
Abstract
The rigid motion of robotic arms is a key factor for precision performance. However, the limitations are that it is bulky in size and have a high cost. Flexible structures can be a good choice for increasing the operating speed of robotic arms, but the drawback is that it sacrifices stability. Inspired by an eye-in-hand robotic system, this study introduces an innovative vision-based structural vibration measurement method by integrating a real-time image recording camera for vibration measurement and feedback control. This method integrates Digital Image Correlation (DIC) with a camera pose estimation algorithm to measure vibrations in flexible structures. A semi-window method was applied to identify the 2D image coordinates, and the actual displacement was determined by incorporating intrinsic parameters, 2D image coordinates, and known 3D coordinates into the camera pose estimation algorithm. To verify this concept, a camera was integrated on a cantilever plate to simulate vibrations of a flexible robotic arm. This system operation was based on the concept that vibrations in the structural plate induce synchronous motion in the camera such that the measured vibrations can effectively be tracked to represent the relative variations in the captured views. The experimental results demonstrated that the vibration displacement at the free end was dominated by the y-direction, with a final RMSE of 0.3762 mm for the estimated displacement in the y-direction. The results confirm that this contact-based vision sensor system can effectively measure the vibration displacement of flexible structures which can contribute to improving future designs and control of flexible robotic arms.
Event(s)
Nondestructive Characterization and Monitoring of Advanced Materials, Aerospace, Civil Infrastructure, and Transportation XIX 2025, Vancouver, 17 March 2025 - 20 March 2025
Subjects
camera
digital image correlation
flexible materials
three-point perspective theory
vibration measurement
SDGs
Publisher
SPIE
Type
conference paper