  Physical therapy (PT) is a key component of many rehabilitation regimens,
such as treatments for Parkinson's disease (PD). However, there are shortages
of physical therapists and adherence to self-guided PT is low. Robots have the
potential to support physical therapists and increase adherence to self-guided
PT, but prior robotic systems have been large and immobile, which can be a
barrier to use in homes and clinics. We present Stretch with Stretch (SWS), a
novel robotic system for leading stretching exercise games for older adults
with PD. SWS consists of a compact and lightweight mobile manipulator (Hello
Robot Stretch RE1) that visually and verbally guides users through PT
exercises. The robot's soft end effector serves as a target that users
repetitively reach towards and press with a hand, foot, or knee. For each
exercise, target locations are customized for the individual via a visually
estimated kinematic model, a haptically estimated range of motion, and the
person's exercise performance. The system includes sound effects and verbal
feedback from the robot to keep users engaged throughout a session and augment
physical exercise with cognitive exercise. We conducted a user study for which
people with PD (n=10) performed 6 exercises with the system. Participants
perceived the SWS to be useful and easy to use. They also reported mild to
moderate perceived exertion (RPE).
