Motion analysis is an area with several applications for health, sports, and entertainment. The high cost of state-of-the-art equipment in the health field makes it unfeasible to apply this technique in the clinics’ routines. In this vein, RGB-D and RGB equipment, which have joint tracking tools, are tested with portable and low-cost solutions to enable computational motion analysis. The recent release of Google MediaPipe, a joint inference tracking technique that uses conventional RGB cameras, can be considered a milestone due to its ability to estimate depth coordinates in planar images. In light of this, this work aims to evaluate the measurement of angular variation from RGB-D and RGB sensor data against the Qualisys Tracking Manager gold standard. A total of 60 recordings were performed for each upper and lower limb movement in two different position configurations concerning the sensors. Google’s MediaPipe usage obtained close results compared to Kinect V2 sensor in the inherent aspects of absolute error, RMS, and correlation to the gold standard, presenting lower dispersion values and error metrics, which is more positive. In the comparison with equipment commonly used in physical evaluations, MediaPipe had an error within the error range of short- and long-arm goniometers.

In general, the motor rehabilitation process can take advantage of natural interaction based systems, including measurements from patient performance to track its evolution during time and therapy direction. Thus, the aim of this research is the analysis of the use of Kinect sensor as interaction support tool for rehabilitation systems. The Kinect sensor gives three-dimensional information about the user body, recognizing skeleton and joint positions, however does not provide the detection of the body specific movements. This way, the correct description of a rehabilitation movement (shoulder abduction, for instance) was implemented in a system prototype. A scoring mechanism was also developed in order to measure the patient performance, as well as to stimulate his improvement by displaying a positive feedback.