Brushless DC Motor Control System for Active Myoelectric Prostheses

Abstract

A prosthesis is an artificial substitute for a missing part of the body that makes it possible to recover some degree of function of the lost limb. Prosthetics are classified as passive and active. These last ones require a driver system and a control system which are indispensable to determine if the motion a person is doing is executing effectively. In this sense, the driver system and the control system play a fundamental role in the functioning of active prosthetics when myoelectric sensors are used for their activation. The following paper presents the development of a Field Oriented Control of position for brushless direct current Motor equipped with Hall effect sensors. The system is built for a 5W EC-max 16 Ø16 mm brushless motor coupled to a GP 16 A Ø16 mm planetary reducer, together with an Arduino Uno board and a simple Field Oriented Control module. An open-loop position control system and a closed-loop position proportional-integral control system were implemented. The results indicate that closed-loop control shows a stability time, rise time, peak time and a steady state error less than the open-loop system. Also, that there is not notable hysteresis in the motor. These results will allow a more precise position control on a myoelectric prosthesis for transhumeral amputees.

Keywords

• active prostheses
• brushless dc motor
• hall effect sensors
• pi control
• simplefoc
• vectorial control