Progressive haptic and visual guidance for training in a virtual dynamic task

This paper presents the design and implementation of a novel progressive haptic guidance scheme and a similar visual guidance scheme for acquisition of a dynamic motor skill. The paper compares the schemes' performance to each other and to practice alone without any form of guidance. The target-hitting task is represented in a visual and haptic virtual environment and implemented in a training protocol that lasts eleven sessions over a two-month period. The progressive guidance controller employs as inputs two expertise-based performance measures, trajectory error and input frequency. The analysis of the experimental results demonstrates that while guidance is active, haptic guidance outperforms both visual guidance and practice alone (no guidance) until late in the protocol when all three groups saturate at the same level of performance. The results fail to show significant differences in training outcomes because the performance of all participants saturates toward the end of the protocol. The key implication of the experimental findings is that visual and haptic guidance presented in a progressive manner have no detrimental effects on performance. Our results confirm that haptic guidance, based on skill component measures, is effective early in the training protocol when participants are only beginning to understand the components of the task but should be progressively removed to avoid possible negative dependence on the guidance.