Citation

Zhang S, Li S, Li X, Xiong Y, Xie Z. J. Intell. Robotic Syst. 2022; 104(1): e18.

Copyright

(Copyright © 2022, Holtzbrinck Springer Nature Publishing Group)

DOI

10.1007/s10846-021-01534-8

PMID

unavailable

Abstract

The most popular safety scheme for human-robot collaboration is that the robot will stop and wait at human's approach. This paper aims to tackle the practically very challenging problem of the balance between efficiency and safety in the safety scheme aforementioned in the intelligent manufacturing industry. The human-robot dynamic fusion algorithm (HRDF) was proposed in this paper to ensure the safety of humans initiatively, in favor of reducing the stop times of the collaborative operations. In this algorithm, the digital dynamics model of human was built and employed to estimate the minimum distance between human and robot in real-time. And the virtual force can be calculated based on the minimum distance above. Subsequently, the value and the time duration of the virtual force were employed to evaluate the safety status of human-robot system. Then, robot can conduct safety planning initiatively according to the safety status. In practice, the average response time taken from the detection of the distance change of human-robot to the adjustment of robot is 0.05s with our algorithm. Above all, the effectiveness of our approach is verified empirically with contact maintenance experiments in a non-stop mode. And the HRDF can maximally increase efficiency by 26.4% compared with the traditional stop-maintenance-restart safety mode.

Language: en

Keywords

Collaborative operations; Human-robot dynamic system; Robot-human safety; Safety state estimation