Sampled- and continuous-time passivity and stability of virtual environments

• Published in: IEEE transactions on robotics Vol. 20; no. 4; pp. 772 - 776
• Main Authors: Jee-Hwan Ryu, Yoon Sang Kim, Hannaford, B.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.08.2004; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied sciences; Computer science; control theory; systems; Contact; Control theory; Control theory. Systems; Controllers; Energy measurement; Exact sciences and technology; Fluid flow measurement; Force measurement; Haptic interfaces; Humans; Miscellaneous; Observers; Passivity; Polycarbonates; Robotics; Robots; Stability; Stiffness; Time domain analysis; User interface; Velocity; Velocity measurement; Virtual environment; Sampled system; Time domain method; User interface; Observer; Virtual reality; Continuous time; System identification; Computer control; Passivity
• ISSN: 1552-3098; 1941-0468
• DOI: 10.1109/TRO.2004.829453

We propose a new time-domain passivity observer (PO) and passivity controller (PC) which removes the constant-velocity assumption during one sample time, which was used in our previous PO/PC approach. A new sampled-time definition of passivity is introduced, and this new definition is compared with the previous sampled-time definition of passivity. Through this comparison, we propose the more accurate PO/PC approach. The proposed new PO/PC approach is applied to the "Excalibur" haptic interface system with very high stiffness (K = 120 kN/spl middot/m) virtual environment, and stable contact is demonstrated.