PROTOTYPE OF AN UPPER LIMB PROSTHESIS DRIVEN BY A GRADUAL FORCE TENSOR
INTRODUCTION: Individuals with upper limb amputation can have a better quality of life with the use of prostheses. Upper limb prostheses can be mechanical, aesthetic, myoelectric, or hybrid. In general, prosthesis models produced by conventional methods are uncomfortable and heavy, so there is a very high rate of abandonment of use. Customized upper limb prostheses have been made in the last 10 years with advanced methods and the use of additive manufacturing technology. However, even these state-of-the-art models present user difficulties such as efforts to actuate active prostheses with a particular body part. OBJECTIVE: To develop and test a mechanical upper limb prosthesis activated by the elbow, with a force tensor device, to regulate the traction on the palmar grip of the prosthesis, allowing the opening or closing of the hand to hold objects, increasing the user's autonomy. MATERIAL AND METHODS: The methodology adopted was the Design Science Research, the most appropriate research method when the objective of the study is to design engineering artifacts to solve a real problem. The artifact development stages included a prototyping cycle for the acquisition of anthropometric measurements, modeling, manufacturing and assembly of the prosthesis and force tensor, and evaluation of the device in bench tests and simulations. RESULTS: The prosthesis with the mechanical force tensor device allows the gradual activation of the functions of opening, closing and remaining with the hand closed, for gripping, with gradual dosage of the applied force. To improve the performance of the gradual force tensor, comfort, safety, and use of the prosthesis, other actuation options need to be tested with volunteers.