Robotic manipulators with unbalanced payloads rotating at nearly constant speeds can often be found in automated manufacturing tasks, such as drilling, grinding and deburring. In this paper, a sliding-mode disturbance observer (SMDOB) is designed for such systems that are subject to unknown periodic disturbances due to unbalanced rotating payloads. Stability of the closed-loop system, in which the SMDOB is in combination with a nominal controller, is addressed. Besides, this paper presents an adaptation algorithm for automatic switching-gain adjustments. To alleviate chatter, this algorithm is able to decrease switching gains according to practical operating conditions of robotic manipulators. An experimental study on a two-link direct-drive robotic manipulator was conducted. The experimental results are reported in this paper with a comparative study, realistically showing the efficacy of the proposed system.
|期刊||Journal of the Brazilian Society of Mechanical Sciences and Engineering|
|出版狀態||已發佈 - 2022 1月|
ASJC Scopus subject areas
- 工程 (全部)