ABSTRACT
Researchers have noticed that elderly people expericnced difficulties in sit-to-stand and stand-to-sit maneuvers (Kao and Huang, 2008). These difficulties may be caused by the decreasing pcrformance of their lower limb muscle or knees. In this paper a chair design with an assistive device underneath the seat was proposed to resolve this problem. The effect of the assistive device was studied via an experiment in which two identical prototypes, chairs A and B, were made; chair A was equipped with an assistive device under the seat while chair B was not. Twenty-two elderly subjects are asked to test the chairs, and their usage patterns were analyzed to determine the effectiveness of the assistive device. Results show that subjectively over 80% of subjects responded that chair A provided them with better mobility. The objective metrics show that the average time needed for getting up and sitting down on chair A is significantly longer than chair B, and this slower pace may reduce the risk for subjects to fall off a chair. The researcher also finds the average leaning angle on the subjects' trunk when using chair A much smaller than chair B. This may suggest chair A is easier to use than chair B. The experiment shows that assistive chair design enables elderly to sit down and get up more easily.
