Robotic Stretcher for Spinal Muscular Atrophy Patient: Test of User Controllability with Operating Device and Monitoring System

Abstract

Diseases such as amyotrophic lateral sclerosis and spinal muscular atrophy (SMA) often cause motor disabilities through the progressive loss of muscle power. Also, many SMA patients must lie horizontally and thus cannot operate a wheelchair. The aim of this study was to develop a robotic stretcher for an SMA patient with severe motor disabilities to enable her to maneuver independently inside a building. The concept underlying the stretcher is that the user should be able to drive the stretcher using a suitable operating device while watching a display feed from cameras mounted on the stretcher. We have developed new devices with an operating device and its algorithm, monitoring system, mechanical frame, and control system tailored to the user’s limited abilities (motion in only one finger). We have verified their functions through tests of a prototype machine operated by the target user. The tests were conducted with the machine positioned on the ground to simulate a shopping mall environment. The subject was able to control the machine effectively, aided by the monitoring system that provided visibility of the stretcher’s position within the environment. Remarkably, even without specific guidance, the subject could operate the stretcher efficiently. To enhance the stretcher’s operability, we considered focusing on controlling the straight motion performance of the mechanical body, which includes two independently motor-driven wheels and casters.