Stretch with Stretch: Physical Therapy Exercise Games Led by a Mobile Manipulator

TL;DR

Stretch with Stretch (SWS) is presented, a novel robotic system for leading stretching exercise games for older adults with PD that includes sound effects and verbal feedback from the robot to keep users engaged throughout a session and augment physical exercise with cognitive exercise.

Abstract

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).

Figures (6)

• Figure 2: Exercises are led by a Hello Robot Stretch RE1 kemp2022design with a soft bubble end effector kuppuswamy2020soft. Users press the bubble with different body parts.
• Figure 3: Actual SWS target locations colored by whether they can be reached (green) or not (red) by a Rethink Robotics Baxter (as used in fitter2020exercising).
• Figure 4: (Left) Exercise model for a seated forward kick. The location of the 50% difficulty point $X_0$ is a function of relevant body dimensions (meters), and is shown as a black sphere. The difficulty vector $\Bar{d}$ is specified absolutely (meters), and is shown as a red arrow. The body part used to make contact with the robot during the exercise is indicated by a blue sphere. (Right) Front and isometric views of each of nine exercise models.
• Figure 5: We performed a user study with 10 PWP. (A-C) Participants performing seated reaching, kicking, and calf raise exercises. (D-F) Participants performing standing reach across, reach down, and high knees exercises. Chairs were placed near the participant as safety devices for the standing exercises.
• Figure 6: Robot Opinions Questionnaire survey response distributions.