RESEARCH ON PELVIC ANGLE VARIATION WHEN USING A PELVIC SUPPORT

A pelvic support consisting of a forward sloping wedge of foam has bee n tested as an addition to conventional office seating for VDT work. I n experiment 1 a questionnaire investigation was carried out on the im pressions of 10 male and 10 female subjects who sat using pelvic suppo rts. A general result from the questionnaire was that the waist and pe lvis were felt to be stable and the evaluation was more positive with the support than without. In experiment 2, pelvis and chest inclinatio ns were measured during sitting with and without the pelvic support. O ver a long work period, significant differences were not observed. In both cases, subjects were able to move freely and there were no signif icant changes in posture. In experiment 3, pelvis and chest inclinatio ns were measured in conditions of no pelvic support and with supports of 10, 20 and 30 degrees. The experiment demonstrated that a support a ngle of 10 degrees was stable and comfortable. In this research, it wa s found that the change of inclination of the pelvis can be measured c ontinuously using an angle of inclination sensor. Imposing a forward s lope of 4 to 10 degrees on the seat pan surface using the pelvic suppo rt had a positive effect, while angles of 20 and 30 degrees had a nega tive effect.