IJE TRANSACTIONS C: Aspects Vol. 32, No. 6, (June 2019) 820-827 Please cite this article as: S. S. Pastor, C. T. Rivera, Ó. F. Avilés * , M. F. Mauledoux, A Real-time Motion Tracking Wireless System for Upper Limb Exosuit Based on Inertial Measurement Units and Flex Sensors, International Journal of Engineering (IJE), IJE TRANSACTIONS C: Aspects Vol. 32, No. 6, (June 2019) 820-827 International Journal of Engineering Journal Homepage: www.ije.ir A Real-time Motion Tracking Wireless System for Upper Limb Exosuit Based on Inertial Measurement Units and Flex Sensors S. S. Pastor, C. T. Rivera, O. F. Avilés*, M. F. Mauledoux Mechatronics Engineering Program, Faculty of Engineering, Militar Nueva Granada University, Bogotá, Colombia PAPER INFO Paper history: Received 09 February 2018 Received in revised form 07 March 2019 Accepted 03 May 2019 Keywords: Motion Tracking Wearable Sensors Upper Limb Exosuit ABSTRACT This paper puts forward a real-time angular tracking (motion capture) system for a low cost upper limb exosuit based on sensor fusion; which is integrated by an elastic sleeve-mitten, two inertial measurement units (IMU), two flex sensors and a wireless communication system. The device can accurately detect the angular position of the shoulder (flexion-extension, abduction-adduction and internal-external rotation), elbow (flexion-extension and forearm supination-pronation), and wrist (flexion-extension) joints. In addition, the state of the hand (opened-closed). Finaly a PID controller is applied to the exosuit in order to replicate the movements performed by the arm into a 6 DOF robot arm. doi: 10.5829/ije.2019.32.06c.04 1. INTRODUCTION 1 Motion capture systems (MOCAP) are useful since they allow to obtain valuable information related to human locomotion, which may be analyzed for different purposes. For instance, to adopt strategies applied to rehabilitation processes, improve techniques to diagnose and treat neuromotor diseases, develop bio-inspired robots (humanoids) with better features and superior performance, enhance human computer interaction providing more intuitive and natural interfaces of control (e.g., operating a robot remotely with the movement of the user arm) [1, 2], apart from other possible applications. Exosuits of human limbs based on soft materials and the fusion of compact sensors (selected according to the type of joint, e.g., to measure elbow movement an adequate option is a bend/flex sensor, since elbow flexion only produces one degree of freedom. Otherwise, to track shoulder motion is useful to utilize an IMU because this joint has three degrees of freedom) that let augmenting mobility of the user without * Corresponding Author Email: oscar.aviles@unimilitar.edu.co (O. F. Avilés) restricting natural kinematics or producing extra loads on it [3-6], are transforming the way in which the motion capture is made, bringing advantages over their predecessors with rigid body structures, such as low costs, light weight, improved comfort and simpler infrastructures [5, 7]. The present work is motivated by master-slave systems existing in robotics, which require intuitive interfaces of control to tele-operate slave machines, in this particular case, humanoid robots. The authors introduced a low cost intuitive mocap system for upper limb, Figure 1, that provides not only good performance, but also a proper transportable ergonomic structure that bring the possibility to control a manipulator remotely, in a simple and intuitive way. Figure 1. Prototype of proposed exosuit for motion tracking of human upper limb TECHNICAL NOTE