Time domain passivity control with reference energy following

• Published in: IEEE transactions on control systems technology Vol. 13; no. 5; pp. 737 - 742
• Main Authors: Jee-Hwan Ryu, Preusche, C., Hannaford, B., Hirzinger, G.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01-09-2005; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied sciences; Computer science; control theory; systems; Control system analysis; Control systems; Control theory. Systems; Damping; Delay effects; Exact sciences and technology; Force control; Haptic interface; Haptic interfaces; Humans; Imaging phantoms; Modelling and identification; passivity controller (PC); passivity observer (PO); reference energy; Robots; System testing; time-domain passivity; Virtual environment; Stabilization; Reference; Remote operation; passivity observer (PO); time-domain passivity; Computer control; Controller; Passivity; Tactile sensitivity; Time varying system; Haptic interface; Time domain method; Energy; User interface; Observer; System identification; reference energy; High frequency; passivity controller (PC)
• ISSN: 1063-6536; 1558-0865
• DOI: 10.1109/TCST.2005.847336

A recently proposed method for stabilizing haptic interfaces and teleoperation systems was tested with a PHANToM commercial haptic device. The passivity observer (PO) and passivity controller (PC) stabilization method was applied to stabilize the system but also excited a high-frequency mode in the device. To solve this problem, we propose a method to use a time-varying desired energy threshold instead of fixed zero energy threshold for the PO, and make the actual energy input follow the time-varying energy threshold. With the time-varying energy threshold, we make the PC control action smooth without sudden impulsive behavior by distributing the dissipation. The proposed new PO/PC approach is applied to PHANToM with high stiffness (K=5000N/m), and stable and smooth contact is guaranteed. Resetting and active environment display problems also can be solved with the reference energy following idea.