Robotic Manipulation Characteristics of Persons with Physical Disabilities

Research Objectives: This study has aimed to gain a better understanding of the characteristics of robotic manipulation performed by persons with physical disabilities.
Design: Case-control study.
Setting: Laboratory-based evaluation with a series of robotic manipulation tasks using a standardized ARM evaluation tool (ARMET). The ARMET is a task board which includes three kinds of common household items (buttons, switches, and knobs) with two different sizes and distances.
Participants: 7 subjects without disabilities (5 males and 2 females) and 7 subjects (6 males and 1 female) who have self-reported upper limb impairments that limit their abilities to perform manipulation tasks of everyday life. All subjects are over 18 years of age. They have normal vision to perform the manipulation tasks.
Interventions: Subjects were asked to complete three trials of three tasks (operating a door handle, turning a knob, manipulating a flip switch) using a touch screen control interface. In addition, they were asked to complete three trials of two real life tasks including picking-and-placing objects (i.e., a ball and a bottled water).
Main Outcome Measure(s): Objective robotic manipulation performance measures (task completion time, # of control commands used, the distance and trajectory moved around, # of sub-movements, and duration of pause).
Results: When performing robotic manipulation, individuals with physical disabilities showed several different characteristics compared to non-disabled individuals. Physically disabled individuals took longer to complete the tasks, required more sue of control commands, paused more often and for longer, showed more sub-movements, lower movement speed, a longer deceleration phase, and traveled longer distance.
Conclusion/Discussion: The physically disabled persons’ assistive robotic manipulation is characterized by longer completion time, more frequent pauses, more sub-movements, more frequent use of control commands, lower velocity, less efficient trajectory, compared to able-bodied individuals.