Vibration Measurement of Robot End-Effector Based on Improved Optical Flow in Stereo Vision

• Published in: International Conference on Automation, Control and Robotics Engineering (Online) pp. 23 - 28
• Main Authors: Wang, Chao, Fang, Lijin, Zhao, Qiankun, Qian, Yian
• Format: Conference Proceeding
• Language: English
• Published: IEEE 16.07.2025
• Subjects: Accuracy; End effectors; Frequency measurement; high-precision measurements; industrial robotic arms; Kalman filtering; Kalman filters; Optical flow; Robot sensing systems; Service robots; sub-pixel corner detection; three-dimensional vibration measurement; Trajectory; Vibration measurement; Vibrations
• ISSN: 2997-6278
• DOI: 10.1109/CACRE66141.2025.11119600

In the high-precision operation of industrial robotic arms, vibrations can reduce the accuracy of the end-effector trajectory. To achieve vibration suppression, it is essential to accurately measure the vibration characteristics, which makes high-precision vibration measurement particularly important. Traditional contact sensors suffer from mass loading effects and complex installation, whereas computer vision-based approaches have gained significant attention in research due to their non-contact nature. We present a binocular vision-based approach for measuring the three-dimensional vibration of the robotic arm's end effector. The technique utilizes sub-pixel corner detection technology, a video motion magnification algorithm, and an improved optical flow tracking algorithm that integrates Kalman filtering and the Hungarian algorithm. Through experimental analysis of robotic arm end-effector vibrations, the visual algorithm's output was validated against contact sensor data, confirming its efficacy in detecting microvibrations. The experimental results demonstrate that this method can achieve a high-precision measurement of minute vibrations, with a measurement accuracy of 0.01 mm. Additionally, experimental results under different load conditions indicate that the vibration frequencies of the three axes of the robot arm's end effector are concentrated around a specific frequency, further demonstrating that the end vibration frequency of the robot arm is not directly related to the magnitude of the applied load.