Range of motion measurement of articulatio cubiti based on hough transformation

Range of Motion (ROM) is one of the movement parameters for evaluating physical rehabilitation Articulatio cubiti or elbow is one of the most important organs in the human body that is most commonly injured in some accidents happens. A physical test is needed using ROM measurement to see the severity of the injury and the effectiveness of rehabilitation. Therefore, accurate and precise ROM measurements are needed to decrease error value while diagnosing injury severity and can represent the actual condition of the joints, so the effectiveness of rehabilitation can be evaluated properly. So far. ROM measurement is still using manual devices, named goniometer. However, this device has several disadvantages: It requires human intervention, requires high clinical experience from a therapist or doctor, and goniometer cannot be used for ROM measurement in certain joints. Therefore, we need a device to do ROM measurement automatically, precise, and flexible. In this research. ROM measurements were taken on Articulatio cubiti dextra using Hough transformation method based on kinect sensors and Python programming language. There are three variations of the distance between human subject and kinect sensor; 140 cm (first distance), 220 cm (second distance), and 300 cm (third distance), and there are 10 variations of ROM values from 4° to 120°. The obtained results showed that the best ROM measurement at a first distance with a linearity of 99.59%, a sensitivity of 97.38%, an accuracy of 96.64%, and a relative standard deviation of 1.65%, followed by ROM measurement result at the second distance with a linearity of 99.46%, a sensitivity of 92.28%, an accuracy of 92.51%. and a relative standard deviation of 5.92%, and the lowest ROM measurement results are at a third distance with a linearity of 99.27%, a sensitivity of 91.68%, an accuracy of 90.25%, and a relative standard deviation of 7.28%.