ABSTRACT
A description of the research and development of the Dynafit chair follows. An experiment was conducted using a three-dimensional model of the human body to evaluate the stability of the Dynafit chair, and its ability to lock in place. The body weight of a three-dimensional human model was set at three levels, and measured with a deflection meter and load cell. The seating comfort of the Dynafit chair was evaluated by the Semantic Differential method. The seated pressure distribution and postural stability were measured to evaluate the degree of support with the dynamic back rest. Seat pressure distributions do not differ appreciably between the upright and reclined positions, and are approximately optimum in each posture. This suggests that the Dynafit chair can provide adequate pressure distribution despite dynamic changes in back rest position. As a result of vertical back rest movement the sitter is afforded considerable freedom of upper body movement, and receives continuous back support.
