Study On The Influences Of Hard Seat Shapes On Human Body Comfort

This thesis use the subjective evaluation and objective evaluation, making a study of the impact of hard seat height, shape of the front section and side section on seat comfort. The main results are as follows:(1) When the seat height is between the popliteal and 20mm below the popliteal, subjective evaluation shows higher comfort.the indicators of body pressure distribution such as the mean pressure, the maximum pressure gradient and the mean pressure gradient are smaller, which shows higher comfort, too. The subjective and objective evaluation show the same result.(2) Under the conditions that the seat height is equal to popliteal height or 20mm lower than the popliteal, the larger the radius of the front section, the better the comfort. When it is not less than 2000mm, the bend will not affect the seat comfort. When it is between 1000mm and 2000mm, seat height can be appropriately reduced to improve comfort, but it should not be less than popliteal height-20mm.(3) To the Seat side section shape, if it is flat around the ischial tuberosity, the comfort will not be affected; while the changes of radius in front of the seat will make a significant influence on subjective and objective assessment results. The radius that bring better comfort should be: 40mm and 80mm for light work chair,80mm and 120mm for light resting chair.