The magnitude of errors associated in measuring the loads applied on an assistive device While Walking

Measurement of the loads exerted on the limb is a fundamental part of designing of an assistive device, which has been done byusing strain gauges or a transducer. although calculation of loads applied on an orthosis coefficients achieved from calibration is astandard way, most of researchers determined the loads based on available equations. therefore, the aim of this research is finding theaccuracy of this method with respect to calibration. some strain gauges were attached on the lateral bar of a reciprocal gait orthosis.it was calibrated for axial force and the anteroposterior and mediolateral moments. the outputs of strain gauge were changed toforce, and moments based on the coefficients were achieved from calibration using available equations, while 5 normal subjects werewalking with the orthosis. there was a significant difference between the force and moments exerted on the orthosis during walkingbased on the two methods (mostly extension moment and compression force). the results of this research indicated that the output ofstrain gauge varies based on the methods of calculation. as calibration the gauge is a standard method, it is recommended to calibrateit before use.