Power-Assist Chair Using Pneumatic Actuator
Kazushi Sanada* and Yuki Akiyama**
*Department of Mechanical Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama City, Kanagawa 240-8501, Japan
**Mechanical Engineering Research Laboratory, Hitachi, Ltd., 832-2 Horiguchi, Hitachinaka-City, Ibaragi 312-0034, Japan
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.
-  K. Kawashima and T. Funaki, “Evaluation of Force Control of Pneumatic Robot Arms Used to Support Rehabilitation,” Trans. of The Japan Fluid Power System Society, 34-1, pp. 14-18, 2003.
-  D. Sasaki, T. Noritsugu, and M. Takaiwa, “Wearable Master-Slave Training Device for Lower Limb Constructed with Pneumatic Rubber Artificial Muscles,” Proc. of the 7th JFPS Int. Symposium on Fluid Power, pp. 1-45, 2008.
-  Y. Shibata, M. Takagi, T. Miyoshi et al., “Development of Gait Training System using Bi-articular Muscle Model,” Proc. of the 7th JFPS Int. Symposium on Fluid Power, pp. 1-47, 2008.
-  T. Arima, O. Oyama, and T. Yoshimitsu, “Development of Walking Assist System with Pneumatic Actuator,” Proc. of the 7th JFPS Int. Symposium on Fluid Power, pp. 1-54, 2008.
-  S. Dohta, T. Akagi, and H. Kuno, “Development of a Skin Displacement Sensor for the Pneumatic Power Assisted System,” Proc. of the 7th JFPS Int. Symposium on Fluid Power, pp. 1-32, 2008.
-  K. Sanada and A. Kitagawa, “A Study on a Power-Assist Chair,” Proc. Fifth Triennial Int. Symposium on Fluid Control, Measurement and Visualization, pp. 491-496, 1997.
-  K. Sanada, “A Study on Control Techniques for Power-assisted Chair,” Proc. of Fourth JHPS Int. Symposium on Fluid Power, Tokyo ’99,” pp. 175-180, 1999.
-  K. Sanada, “Power-Assisted Chair with Virtual Spring,” Proc. of Sixth Triennial Int. Symposium on Fluid Control, Measurement and Visualization, paper No.083, 2000.
-  K. Sanada, “Power-assisted Chair with Virtual Spring,” Trans. of The Japan Fluid Power System Society, 31-2, pp. 38-43, 2000.
-  K. Sanada, “A Study on Virtual Spring Characteristics of a Powerassisted Chair,” Trans. of The Japan Fluid Power System Society, 32-2, pp. 41-45, 2001.
-  K. Sanada, T. Takamura, and Y. Fujimaki, “A Study on Design and Evaluation of a Power-assisted Chair,” SICE Annual Conf. 2005 in Okayama, pp. 3074-3078, 2005.
-  Y. Fujimaki, K. Sakaino, M. Fukuta, and K. Sanada, “A Study on Control and Measurement of a Power-Assisted Chair,” Proc. of the 6th JFPS Int. Symposium on Fluid Power, TSUKUBA 2005, pp. 179-184, 2005.
-  K. Sanada, A. Kawamura, and Y. Akiyama, “A study on power assisted chairs,” Asia Int. Symposium onMechatronics 2008, pp. 456-459, 2008.
-  Y. Akiyama and K. Sanada, “A Study on Control of a Power-assisted Chair Based on Motion-sensing Concept,” SICE-ICASE Int. Joint Conf. 2006, pp. 5200-5203, 2006.
-  Y. Akiyama and K. Sanada, “A Study on A Power-Assisted Chair with Motion Sensing,” Trans. of The Japan Fluid Power System Society, 41-6, pp. 107-114, 2010.
-  T. Kagawa, M. Shimizu, and Y. Ishii, “A Study on the Meter-out Velocity Control of a Pneumatic Cylinder (Consideration of Air Temperature Change Effects),” J. of the Japan Hydraulics & Pneumatics Society, pp. 93-99, 1992.