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Title: Robust planar dynamic pivoting by regulating inertial and grip forces
In this paper, we investigate the planar dynamic pivoting problem, in which a pinched object is reoriented to a desired pose through wrist swing motion and grip force regulation. Traditional approaches based on friction compensation do not work well for this problem, as we observe the torsional friction at the contact has large uncertainties during pivoting. In addition, the discontinuities of friction and the lower bound constraint on the grip force all make dynamic pivoting a challenging task for robots. To address these problems, we propose a robust control strategy that directly uses friction as a key input for dynamic pivoting, and show that active friction control by regulating the grip force significantly improves system stability. In particular, we embed a Lyapunov-based control law into a quadratic programming framework, which also ensures real-time computational speed and the existence of a solution. The proposed algorithm has been validated on our dynamic pivoting robot that emulates human wrist-finger configuration and motion. The object orientation can quickly converge to the target even under considerable uncertainties from friction and object grasping position, where traditional methods fail.  more » « less
Award ID(s):
1813920 1909021 1637908
PAR ID:
10167959
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Algorithmic Foundations of Robotics XII
Volume:
13
Page Range / eLocation ID:
464 - 479
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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