College of Engineering and Applied Sciences Motion Control of Robot for passive rehabilitation of human shoulder Presented by Md Rasedul Islam PhD Student Mechanical Engineering Department Mechanical Engineering Department

American Heart Association reports Mechanical Engineering Department College of Engineering and Applied Sciences American Heart Association reports Approximately 785,000 persons experiences a new or recurrent cerebral vascular accident (CVA) in US Among which 58000 people experience mobility impairment Having difficulty doing ADLs (Reaching, Gripping, Touching etc) It is essential to restore motor function in order to perform ADL and return the domestic and social life Task specific Repetitive therapy program help regain lost mobility Limited number of health professionals Incorporation of robots in rehabilitation started back in early 1990s Mechanical Engineering Department

Robots in Rehabilitation Mechanical Engineering Department College of Engineering and Applied Sciences Robots in Rehabilitation Robots have the potentiality in rehabilitation programs. Incorporation of robots in rehabilitation started back in early 1990s. Two types end-effector type (MIT-Manus) and exoskeleton type (Armin-III) In this project, a robotic device for shoulder rehabilitation were designed and controlled. Mechanical Engineering Department

Mechanical Engineering Department College of Engineering and Applied Sciences Range of movements The table shows the range of movement and adopted from winter (2008). The current robots has 3 DOF with wider range of motion   Shoulder Joint Types of Motion Range Joint 1 Abduction 180 Adduction -50° Joint 2 Vertical Flexion 180° Vertical Extension Joint 3 Internal Rotation -90° External Rotation 90° Mechanical Engineering Department

Mechanical Engineering Department College of Engineering and Applied Sciences Kinematic Model Table-2: Modified Denavit-Hartenberg parameters Joint (i) αi-1 ai-1 di θi 1 θ1 2 90° θ2 3 L2 θ3 Figure: Link-Frame assignment Mechanical Engineering Department

Mechanical Engineering Department College of Engineering and Applied Sciences Control A non linear computed torque control technique was used to control the robot Figure: Control Architecture Mechanical Engineering Department

Mechanical Engineering Department College of Engineering and Applied Sciences Simulation To evaluate the performance of developed control technique, simulation was run to see the trajectory tracking of each joint movement. Figure: Simulation result Mechanical Engineering Department

Simulation (Continued) Mechanical Engineering Department College of Engineering and Applied Sciences Simulation (Continued) The above graphs plotted from simulated results show comparison of measured trajectory (outcome of simulation) with desired trajectory (given), error and required torque as well. The measured trajectory is almost overlapped the given trajectory (Plot of angle against time). The error (difference between reference and given trajectory) is lower than 0.05° that shows the efficacy of controller (Plot of error against time). The control is robust enough to handle the Nosie. Mechanical Engineering Department

Mechanical Engineering Department College of Engineering and Applied Sciences Future Works Our ultimate goal is to develop a whole arm wearable exoskeleton for supper limb rehabilitation. The proposed exoskeleton would be smart and intelligent. It would have a fine and adaptive controller. The control with EMG and signal would be incorporated in the controller. Mechanical Engineering Department

Mechanical Engineering Department College of Engineering and Applied Sciences Thanks Mechanical Engineering Department

Mechanical Engineering Department College of Engineering and Applied Sciences References Mozaffarian, D., Benjamin, E.J., Go, A.S., Arnett, D.K (2015). "Heart disease and stroke statistics—2015 update: a report from the American Heart Association". American Heart Association. Circulation. 2015;131:e29–e322 Heidenreich, P., Trogdon, J (2011). "Forecasting the Future of Cardiovascular Disease: A Policy Statement from the American Heart Association. Circulation" Circulation. 2011;123:933-944. https://doi.org/10.1161/CIR.0b013e31820a55f5 Craig, John J. Introduction to Robotics: Mechanics and Control. Noida, India: Dorling Kindersley (India) Pvt. Ltd, 2009. Print. 4. Pons JL, ed. Wearable robots: biomechatronic exoskeletons, vol. 338. Hoboken, NJ: Wiley; Mechanical Engineering Department