Assistkey: Efficient Operation & Mode Selection of a Wheelchair-mounted Assistive Robot

Research Objectives: We have developed AssistKey, which incorporates mode control and operation functions in a compact 8-key input device in which the key operations can be switched between different motion commands of a 6 degrees of freedom (DoFs) assistive robotic arm and a gripper and an efficient method of switching between the function mode of each key. AssistKey aims to enable complex operations of an assistive robot within the limited activity range of a single finger, improving the user’s ease and capability of performing activities of daily living with the help of a wheelchair-mounted assistive robot.

Design: Experimental study.

Setting: In the BioRobotics Laboratory.

Participants: We conducted experiments with six healthy individuals (age: 25-45 years, weights: 140–180 lb, height: 1.5–1.85 m) to manipulate a wheelchair-mounted assistive robot with the AssistKey to perform activities of daily living (ADL) tasks.

Interventions: Participants are seated in a powered wheelchair. The multifunctional robotic assistive arm (mR2A) was mounted on the wheelchair. Participants used the AssistKey to control mR2A performing activities of daily living (ADLs), such as picking/placing and manipulating objects in identified workspaces.

Main Outcome Measures: The study focused on assessing improvements in user’s ease and capability of controlling the assistive robot using AssistKey in contrast of using the wheelchair joystick for robot operations. User’s ease of switching between different directions of motion, and rate of error of user input for desired motion is used as the performance metric.

Results: Preliminary findings suggest that the intuitive design of the 8-key input device allowed users to efficiently switch between different modes and control the multifunctional robotic assistive arm (mR2A) with ease. However, the proximity of the keys on AssistKey may pose difficulties in accurately pressing individual buttons, and combined button presses, intended for more complex operations, were particularly challenging for individuals with limited fine motor skills.

Conclusions: The AssistKey's seamless functions enhance ADL performance, but its design needs refining for users with diverse motor skills. Future versions should focus on ergonomic improvements and adaptive technologies to ease button use and manage complex operations. By resolving these issues, AssistKey could better serve a broader disability spectrum, enhancing user independence and quality of life.

Author(s) Disclosures: The authors declare that they have no conflict of interest.