Fundamental limits in the rendering of virtual haptic textures

We discuss the properties of force-feedback haptic simulation systems that fundamentally limit the re-creation of periodic gratings, and hence, of any texture. These include sampling rate, device resolution, and structural dynamics. Basic sampling limitations are analyzed in terms of the Nyquist and the Courant conditions. The analysis proposes that noise due to sampling and other sources injected in the system may prevent it to achieve acceptable performance in most operating conditions, unless special precautions such as the use of a reconstruction filter, make the closed-loop more robust to noise. The structural response of a PHANTOM 1.0 A device was such that no such filter could be found, and the system introduced heavy distortion in gratings as coarse as 10 mm. The Pantograph Mark-II device having more favorable structural properties could reliably create gratings between 1 and 10 mm.

[1]  Frank Tendick,et al.  A Critical Study of the Mechanical and Electrical Properties of the PHANToM Haptic Interface and Improvements for Highperformance Control , 2002, Presence: Teleoperators & Virtual Environments.

[2]  Vincent Hayward,et al.  Design and multi-objective opti-mization of a link a for a haptic interface , 1994 .

[3]  Bruce A. Francis,et al.  Feedback Control Theory , 1992 .

[4]  M. Cutkosky,et al.  Roughness Perception of Haptically Displayed Fractal Surfaces , 2000, Dynamic Systems and Control: Volume 2.

[5]  Vincent Hayward,et al.  International Conference on Intelligent Robots and Systems The Pantograph Mk-II : A Haptic Instrument * , 2005 .

[6]  Stephen P. Boyd,et al.  Closed-Loop Convex Formulation of Classical and Singular Value Loop Shaping , 1993 .

[7]  Wright-Patterson Afb,et al.  Judging the Orientation of Sinusoidal and Square-Wave Virtual Gratings Presented via 2-DOF and 3-DOF Haptic Interfaces 1 , 2000 .

[8]  Vincent Hayward,et al.  Change of Height: An Approach to the Haptic Display of Shape and Texture Without Surface Normal , 2002, ISER.

[9]  Dinesh K. Pai,et al.  Haptic texturing-a stochastic approach , 1996, Proceedings of IEEE International Conference on Robotics and Automation.

[10]  Vincent Hayward,et al.  FREEDOM-7: A High Fidelity Seven Axis Haptic Device with Application to Surgical Training , 1997, ISER.

[11]  Roderick Murray-Smith,et al.  Haptic granular synthesis: targeting, visualisation and texturing , 2004 .

[12]  Vincent Hayward,et al.  Discrete-time adaptive windowing for velocity estimation , 2000, IEEE Trans. Control. Syst. Technol..

[13]  Kenneth E. Barner,et al.  Stochastic models for haptic texture , 1996, Other Conferences.

[14]  Vincent Hayward,et al.  Performance Measures for Haptic Interfaces , 1996 .

[15]  Ming C. Lin,et al.  A perceptually-inspired force model for haptic texture rendering , 2004, APGV '04.

[16]  Hong Z. Tan,et al.  Perceived Instability of Virtual Haptic Texture. I. Experimental Studies , 2004, Presence: Teleoperators & Virtual Environments.

[17]  J. Edward Colgate,et al.  Factors affecting the Z-Width of a haptic display , 1994, Proceedings of the 1994 IEEE International Conference on Robotics and Automation.

[18]  Thomas H. Massie,et al.  The PHANToM Haptic Interface: A Device for Probing Virtual Objects , 1994 .