Development of Ergonomic Balance Seat(e-BASE) Chair

Abstract

Objective: The aim of this study is to develop an ergonomic office chair that has an alarm function for the unbalanced sitting postures. Background: Contrary to expectation, it is reported that office workers sit on their chairs much more in unbalanced postures during daily work. Even though an office worker uses an ergonomically good-designed chair and begins their work in a good sitting posture, his/her posture is likely to shift to the unbalanced bad posture. Therefore, a posture alarm system would be very helpful in keeping office workers' good postures. Method: We developed a prototype chair with four load cells under a seat pan and one load cell beneath a backrest. Through some experiments, we set the criteria for unbalanced bad postures then implemented the criteria into the alarm system of the prototype chair. The chair called e-BASE chair could detect unbalance postures and show alarms for chair users. We also enhanced back support by developing a step-wised folding backrest. Results: The e-BASE chair showed better performance in interface pressure distributions and balanced posture ratio in VDT work. Conclusion: The ergonomic chair with posture alarm function(e-BASE chair) was developed. It showed better performance in seat pressure distribution and in keeping good posture during office work. Application: The posture alarm system and folding backrest can be applied to the new models of office chair.