Contribution of artificial proprioception on a dynamic finger flexion task

Authors: MEHDI HOJATMADANI, EVREN SAMUR

Abstract: There has been a considerable effort to provide sensory feedback for myoelectric prostheses. Among the solutions provided in the literature, sensory substitution is an easy and cost-effective way to provide feedback through different sensory modalities at different locations on the body. In this study, we evaluate the effect of sensory substitution of force and position feedback on a two-degree-of-freedom dynamic finger flexion task. For this purpose, a new methodology and an experimental setup are developed. The experimental methodology is based on the "strength-dexterity test", working on the principle of buckling of compression springs. The experimental setup comprises a haptic interface, an input device, a force sensor, two vibration feedback tactors, and a virtual environment. A psychophysical test is conducted where subjects interact with a virtual spring with the index finger of their dominant hand through the haptic interface, the input device, or the force sensor in either isotonic or isometric mode. Three feedback conditions are tested: no sensory substitution, modality-matched sensory substitution, and modality-mismatched sensory substitution (through vibration). Sensory substitution feedback is provided on the subject's contralateral arm. Results show that sensory substitution of force and position does not have a significant contribution to subjects' performance in the proposed dynamic task.

Keywords: Robotics, interaction, virtual environment, sensory feedback, proprioception

Full Text: PDF