Transcript Artificial Muscle based on Flexinol motor wire

Intelligent Robotics Laboratory
Vanderbilt School of Engineering
Artificial Muscle based on
Flexinol motor wire
Scott Renkes
Advisor: David Noelle
Intelligent Robotics Laboratory
Vanderbilt School of Engineering
Purpose
 Design a new actuator
 Robotics
 Prosthetics
 Teleoperation
Intelligent Robotics Laboratory
Vanderbilt School of Engineering
Current Technology
Actuator
Electric
Motors
Hydraulics
Pros
Light weight
Low power
consumption
High force
Cons
Limited torque
Stress on axel
Heavy
Pump required
Pneumatics Medium force Non linear
Elastic
Pump required
Intelligent Robotics Laboratory
Vanderbilt School of Engineering
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
Intelligent Robotics Laboratory
Vanderbilt School of Engineering
Fibrous Bundled Structure
 Flexinol motor wire to
replace muscle fibers
 Package wires similar
to muscle
 Flexinol/muscle fiber
proportional elasticity
 Similar force/length
curves
Intelligent Robotics Laboratory
Vanderbilt School of Engineering
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
Intelligent Robotics Laboratory
Vanderbilt School of Engineering
Flexinol Properties
Diameter Linear
Resistance
(mm)
(W/m)
Typical
current
(mA)
Deformation Recovery Typical
Weight
Weight
Rate
(g)
(g)
(cyc/min)
37
860
30
4
20
55
100
150
180
28
150
43
250
31
610
110
930
19
375
8
2750
393
2000
5
Intelligent Robotics Laboratory
Vanderbilt School of Engineering
Neural Net Recruiting
 Neural Net Basics
 Learning
 Memory
 Back Propagation
 Neural Net
Implementation
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Computer
Microcontroller
Amplifier
Force Controlled
 Force feedback
 Desired Force
Intelligent Robotics Laboratory
Vanderbilt School of Engineering
EMG Controller
 Muscle Voltage vs
Muscle Force
 EMG signals
represent muscle
force
 Neural Network for
EMG pattern
recognition
Intelligent Robotics Laboratory
Vanderbilt School of Engineering
Human Like?
 Force length curve
 Normalized
 Recruitment
 Use neuron control
method
 Inverse Dynamics
Intelligent Robotics Laboratory
Vanderbilt School of Engineering
Sneak Preview
Intelligent Robotics Laboratory
Vanderbilt School of Engineering
Project Status
 Completed work
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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
Intelligent Robotics Laboratory
Vanderbilt School of Engineering
Future Work
 Code user friendly interface for training
and controlling neural network
 Implement portable microcontroller neural
networks
 Design portable batter pack to drive
system
Intelligent Robotics Laboratory
Vanderbilt School of Engineering
Questions?