On the efficacy of haptic guidance schemes for human motor learning

Official URL: http://www.wc2009.org/World-Congress-2009/Pages/Home.aspx

This article investigates the efficacy of different haptic guidance schemes on human motor learning. In particular, the performances of four training protocols, virtual practice, virtual fixtures, fixed-gain error-reducing shared control, and progressive error-reducing shared control, are compared. The experimental results indicate that, if not designed carefully, haptic guidance protocols may be detrimental on motor learning, since such schemes actively interfere with the coupled system dynamics and cause participants to experience task dynamics that are altered from those of the real task. Results also show that the amount of assistance is an important factor, and fixed-gain assistance schemes may cause subjects to gain dependence on the existence of the guidance. Adjusting the amount of haptic guidance based on performance, utilizing progressive gains, is shown to increase the training effectiveness when compared to fixed gain controllers. Key parameters that influence the principles of motor learning in healthy human subjects may guide the design of more effective rehabilitation training protocols.