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

2. Purpose
Design a new actuator
Robotics
Prosthetics
Teleoperation

3. 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

4. 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

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

6. 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

7. 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

8. 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

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

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

11. Sneak Preview

12. 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

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

14. Questions?