Power-Assist Chair Using Pneumatic Actuator

Abstract

The power-assist chair we propose helps the user stand from a sitting position in the chair and sit down. The pneumatic cylinder pushes the seat up. The seat angle is detected by a rotary potentiometer and force acting on the user’s foot is measured by a force sensor. These signals are input to a computer and cylinder pressure is controlled so the seat simulates a spring. We also propose the concept of motion-sensing control based on real-time modification of a nominal seatangle pattern that, in turn, is based on the difference between a nominal pattern and the actual pattern of the foot force. A pneumatic simulation model was built to ensure power-assist chair use motion-sensing control. Experiment and simulation confirmed that the power-assist chair’s motion-sensing control operated as intended.