A methodology for documenting hand positions and forces during manual work.

In the course of a study to determine work methods associated with occupational wrist injuries, a low cost method was developed for estimating the frequencies that various hand positions and the corresponding hand forces were used for certain manual jobs. Hand positions were documented by filming the hands of a worker with a super 8 mm motion picture camera at four frames per sec. (gee Fig. 1). The film was then reviewed frame by frame through several work cyclest. The positions from each frame were noted, plotted and summarized as is shown in Fig. 2. The hand forces were estimated from the integrated Fig. 1. Cinematography and ekctromyography were used to