The use of joint coordinates to monitor patients in a movement-based interaction system

Movement-based interaction has brought about new possibilities in healthcare environments. Concretely, rehabilitation therapies represent an adequate domain in which this kind of systems can produce significant benefits. In this context, the authors have developed SIVIRE, a movement-based interaction system whose main contributions are a virtual online editor of exercises with the capacity to adapt the rehabilitation to the patients’ conditions and evolution. During the development process, we have considered some aspects regarding the monitoring process to improve the quality and accuracy of the system, such as monitoring the patient’s postures, which is a critical procedure in order to properly correct and guide them. Specifically, this paper presents a descriptive study of three methods that address the monitoring process in a different way: the first using joint coordinates, the second based on bones coordinates and the last using the angles generated by the bones. Following the analysis of these three different mechanisms, the authors discuss the reason to identify the use of joint coordinates as the best technique to monitor patients in this kind of movement-based interaction systems. Such technique has been applied in the development of SIVIRE. Finally, we present the results of the evaluation of the system implemented with this monitoring mechanism. The outcomes prove that SIVIRE offers a reliable and useful tool to support rehabilitation therapies, both for patients and physiotherapists.