Design of a device for passive knee auto-rehabilitation

Abstract

During 2016, 408,021 people with disabilities have been registered in Ecuador, from which 193,520 are physically handicapped and 9,895 of them have pathological damage in the knee, which evidences there is a high percentage of the population that needs knee rehabilitation, a problem that, in its first stage, might cause the patient is not be able to make any efforts on the knee.In order to treat this type of conditions, the use of various automated devices is common. Said devices are usually imported, which implies a high cost associated with the product. From this, it arises the need to make a conceptual design of a passive knee rehabilitation with a user’s input, composed of a simple geometry mechanism, built with materials found in the country and at the lowest possible cost. In this research, there is a hierarchical analysis of alternatives to select the one that complies globally with the aforementioned criteria and that allow to develop flexion and extension movements. It is also taken into account the aesthetic part and the needs of the product supported by the indications and the information collected with physiotherapists and oriented to the self-rehabilitation of the adult population of Ecuador. The results have shown that is possible to materialize a design which combines a cinematic analysis and resistance of materials using CAD-CAE programs that serve to completely define the geometry and materials of the device based on a mechanism of four bars, which allows flexion-extension movements of 170º to 90º that correspond to the knee rehabilitation phases. Also, it incorporates exterior forms with a chromatic set with colors that awaken and stimulate the activity of rehabilitation, these colors harmonize design with the orientation of the product.