Adaptive passivity-based control of a flexible-joint robot manipulator subject to collision. (April 2015)

• Record Type: Journal Article
• Authors: Mahmoodi, Masih; Manesh, Mohammad Kojouri; Eghtesad, Mohammad; Farid, Mehrdad; Movahed, Saeid
• Is Part Of: Proceedings of the Institution of Mechanical Engineers. Volume 229:Number 5(2015)
• Page Start: 840
• Page End: 849
• Publication Date: 2015-04
• Subjects: Adaptive passivity-based method -- collision -- post-impact tracking control -- flexible-joint robot; Mechanical engineering -- Periodicals; 621.05
• DOI: 10.1177/0954406214541633
• Languages: English
• ISSNs: 0954-4062

Abstract

In this paper, passivity-based methods are used to perform tracking control of flexible robot manipulators subject to impact collision. The model taken for colliding system is an n-degree of freedom body moving in the manipulator's workspace. Impulsive forces generated in the course of impact cause sudden changes in velocity/acceleration of the links of robot and the colliding system. On the other hand, under-actuated systems subject to impact are likely to have instabilities, or poor transient responses, due to excitation of some un-actuated states. The proposed adaptive passivity-based controller not only improves the post-impact transient response of the under-actuated system (e.g. flexible-joint robot), but also needs no force sensor to measure impulse force during the impact phase of robot motion. The main advantage of the proposed controller relative to model-based inverse-dynamic algorithms is its highly robust characteristics in dampening effects of oscillation right after impact collision for an under-actuated system. This can be done through the introduction of an energy-storage function which incorporates the effects of both actuated and un-actuated states of the system.