Customization, control, and characterization of a commercial haptic device for high-fidelity rendering of weak forces

Netta Gurari*, Gabriel Baud-Bovy

*Corresponding author for this work

Research output: Contribution to journalArticle

14 Scopus citations

Abstract

Background: The emergence of commercial haptic devices offers new research opportunities to enhance our understanding of the human sensory-motor system. Yet, commercial device capabilities have limitations which need to be addressed. This paper describes the customization of a commercial force feedback device for displaying forces with a precision that exceeds the human force perception threshold. New method: The device was outfitted with a multi-axis force sensor and closed-loop controlled to improve its transparency. Additionally, two force sensing resistors were attached to the device to measure grip force. Force errors were modeled in the frequency- and time-domain to identify contributions from the mass, viscous friction, and Coulomb friction during open- and closed-loop control. The effect of user interaction on system stability was assessed in the context of a user study which aimed to measure force perceptual thresholds. Results: Findings based on 15 participants demonstrate that the system maintains stability when rendering forces ranging from 0-0.20. N, with an average maximum absolute force error of 0.041. ±. 0.013. N. Modeling the force errors revealed that Coulomb friction and inertia were the main contributors to force distortions during respectively slow and fast motions. Comparison with existing methods: Existing commercial force feedback devices cannot render forces with the required precision for certain testing scenarios. Building on existing robotics work, this paper shows how a device can be customized to make it reliable for studying the perception of weak forces. Conclusions: The customized and closed-loop controlled device is suitable for measuring force perceptual thresholds.

Original languageEnglish (US)
Pages (from-to)169-180
Number of pages12
JournalJournal of Neuroscience Methods
Volume235
DOIs
Publication statusPublished - Sep 30 2014

    Fingerprint

Keywords

  • Force feedback device
  • Force perception
  • Grip force measurement
  • Haptics
  • Stability
  • Transparency

ASJC Scopus subject areas

  • Neuroscience(all)

Cite this