Task-Oriented Performance Evaluation for Assistive Robotic Manipulators: A Pilot Study.

OBJECTIVE: The objectives of this study were to evaluate the performance of commercially available assistive robotic manipulators (ARMs) user interfaces and to investigate the concurrent validity and sensitivity to change with task-oriented performance evaluation tools (TO-PETs) for ARMs.

DESIGN: This was a nonblinded randomized controlled study with power-wheelchair users with upper-extremity impairments (N = 10). Participants were trained to use 2 ARMs with their respective original user interfaces (keypad and joystick) and evaluated the performance using TO-PET and the adapted Wolf Motor Function Test (WMFT-ARM). Task completion time, ISO 9241-9 throughput, trajectory parameters, NASA-TLX, and questionnaires were the main outcome measurements. Concurrent validity and sensitivity were evaluated.

RESULTS: Statistical differences were found in ISO 9241-9 throughput between the 2 user interfaces for the single motion tasks and WMFT-ARM. However, there was no statistical difference found on the self-reported perceived workload and ease of use. Moderate to high correlation was found between the TO-PET and WMFT-ARM (P < 0.001). The TO-PET demonstrated higher Cohen d (0.910-1.085) than the WMFT-ARM.

CONCLUSIONS: The findings of this study provide a preliminary comparison between 2 commercial ARMs with their different user interfaces among novice ARM users. Recommendations for training and evaluation were revealed.