Image-Processing-based Digital Goniometer using OpenCV

A goniometer measures the available range of motion of an object. In medicine, this instrument is used assessment tool for joints in the body that allows physicians to evaluate a patient's condition, which then enables therapeutic adjustments. In order to improve recording diagnosis history, and the measurement process itself, this study aimed to create a digital goniometer that allows instantaneous measurement of the elbow and knee joint angles, through pictures. The device was made possible through the use of Raspberry Pi, a microcomputer capable of supporting functional applications through integration of hardware and software components. Statistical analysis shows a 98.25% and 98.09% accuracy for the elbow and knee joints respectively, resulting from closely related values between the actual goniometer, and the device created from this study.