Validation of a Frequency Weighted Filter for Repetitive Wrist Flexion Tasks against a Load
This experiment validates an instrument that implements a force and frequency weighted filter for biomechanical stress exposure assessment. This filter network was developed based on a previously established discomfort model that associated physical stress of force, posture and repetition with subjective discomfort. A simulated industrial task was used in the current study to test the instrument involving repetitively transferring a peg and inserting it into a hole against a controlled resistance. Ten subject performed the task for six conditions. Continuous wrist angular data were recorded using an electrogoniometer and processed through the filter. Subjective discomfort was reported after performing the task for one hour using a 10 cm visual analog scale. The discomfort model was shown to estimate relative discomfort for the experimental conditions tested ( r2 = 0.98, p < .05). Linear regression analysis showed that the instrument aptly predicted subjective discomfort ( r2 = 0.87, p < .05). Applications and limitations of this instrument are explored.