Artificial Muscle based on Flexinol motor wire Scott Renkes Advisor: David Noelle

Purpose Design a new actuator Robotics Prosthetics Teleoperation

Current Technology Actuator Pros Cons Electric Motors Light weight Low power consumption Limited torque Stress on axel Hydraulics High force Heavy Pump required Pneumatics Medium force Elastic Non linear

Why a new actuator? Replicate human movement Refined force and velocity control of device Human like movement allows for better man machine integration Humanoid robots can more easily mimic humans

Fibrous Bundled Structure Flexinol motor wire to replace muscle fibers Package wires similar to muscle Flexinol/muscle fiber proportional elasticity Similar force/length curves

Recruitment One bundle, one neuron Weak fast, slow strong Properties of motor wire allow for variety of activation Neural Network Controller Force feedback training Inverse Dynamics

Flexinol Properties Diameter (mm) Linear Resistance (W/m) Typical current (mA) Deformation Weight (g) Recovery Weight Typical Rate (cyc/min) 37 860 30 4 20 55 100 150 180 28 43 250 31 610 110 930 19 375 8 2750 393 2000 5

Neural Net Recruiting Neural Net Basics Neural Net Implementation Learning Memory Back Propagation Neural Net Implementation Computer Microcontroller Amplifier Force Controlled Force feedback Desired Force

EMG Controller Muscle Voltage vs Muscle Force EMG signals represent muscle force Neural Network for EMG pattern recognition

Human Like? Force length curve Recruitment Inverse Dynamics Normalized Use neuron control method Inverse Dynamics

Sneak Preview

Project Status Completed work Current Work Study properties of motor wire Calculate efficiency of passive cooling Develop Structure and Control for the device Design test bed Examine neural network solution Current Work Finish building actuator

Future Work Code user friendly interface for training and controlling neural network Implement portable microcontroller neural networks Design portable batter pack to drive system

Questions?