Evaluating Feedback Modality Preferences of Power Wheelchair Users During Manual Robotic Arm Control.

Assistive robotic arms can extend a user's capabilities, but they can be hard to control because users do not always have good situational awareness at the robot's end effector. This study investigates whether explicit feedback about the robot's distance to task-relevant objects can help users manually control such robots more easily. Specifically, we investigate light and sound as feedback modalities. In a within-subjects study, users controlled a robot arm in a kitchen task. We compared a no-feedback condition with four feedback types: discrete light, discrete sound, continuous light, and continuous sound. We assess usability, performance outcomes, mental workload and user preferences. Our findings indicate that adding feedback improved task success; however, user preferences did not consistently align with performance metrics like task efficiency or success. Instead, preferences varied, revealing insights into user perspectives on each feedback modality.