Prepared by: Jonathan Tran Dept. of Electrical and Computer Engineering Utah State University

1. ECE5320 MechatronicsAssignment#01: Literature Survey on Sensors and Actuators Topic: Shape Memory Alloy Prepared by: Jonathan Tran Dept. of Electrical and Computer Engineering Utah State University E: jon.tran@aggiemail.usu.edu F: (435)797-3054 (ECE Dept.) 3/11/2010

2. Outline • Reference List • To Probe Further • What is a Passive Infrared Sensor? • Major Applications • Practical Applications • How It Works • Pseudo-elasticity applications • Major Specifications • Limitations • Cost • Where to Buy ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

3. Reference list • http://en.wikipedia.org/wiki/Shape_memory_alloy • http://www.stanford.edu/~richlin1/sma/sma.html • http://www.smaterial.com/SMA/sma.html • http://webdocs.cs.ualberta.ca/~database/MEMS/sma_mems/sma.html ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

4. To explore further (survival pointers of web references etc) • http://www-civ.eng.cam.ac.uk/dsl/sma/smasite.html • http://eap.jpl.nasa.gov/ • http://www.shape-memory-alloys.com/ ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

5. What is a Shape Memory Alloy (SMA)? • An alloy that has exhibits pseudo-elasticity and shape memory effect • Shape memory effect – ability to return to an original shape after being deformed by heating • Common alloys are NiTi, CuZnAl, and CuAlNi • Variations can be created using copper, zinc, gold, and iron ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

6. Major applications • Aeronautics • Wings • Alternatives to hydraulic systems • Medical • Optometry • Bone reconstruction • Piping • Robotics • Artificial limbs ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

7. Practical Applications Robots can be given a more fluid movement in joints and limbs http://webdocs.cs.ualberta.ca/~database/MEMS/sma_mems/sma.html ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

8. Practical Applications (2) Bone plates made of SMAs can be used to apply constant pressure to help heal bones more efficiently http://webdocs.cs.ualberta.ca/~database/MEMS/sma_mems/sma.html ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

9. Practical Applications (3) Plane wings with SMA wires can change shape by inducing voltages in them. This can replace hydraulic and electromechanical actuators. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

10. Practical Applications (3 cont.) http://webdocs.cs.ualberta.ca/~database/MEMS/sma_mems/sma.html ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

11. How It Works • Alloy undergoes a solid state phase change • Alloy transition from the Martensite to the Austenite phase • Martensite phase – alloy is relatively soft and easily deformed, occurs at low temperatures • Austenite phase – alloy is stronger and in a more rigid state, occurs at higher temperatures ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

12. How It Works (2) • This illustration shows the micro and macroscopic views of the alloy http://webdocs.cs.ualberta.ca/~database/MEMS/sma_mems/sma.html ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

13. How It Works (3) • This figure shows the phases of the alloy as load and temperature are varied http://webdocs.cs.ualberta.ca/~database/MEMS/sma_mems/sma.html ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

14. How It Works – Pseudo-elasticity • Occurs when an alloy is completely in the Austenite phase • Is not dependent on temperature • When the load is increased to a point, the alloy transitions from the Austenite phase to the Martensite phase • Once the load is removed, the alloy returns to the it original Austenite shape ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

15. Pseudo-elasticity applications • Eyeglass Frames • Bra Underwires • Medical Tools • Cellular Phone Antennae • Orthodontic Arches ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

16. Major Specifications • Phase temperatures • Fatigue life • Range of displacement • Transformation Hysteresis ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

17. Limitations • Functional fatigue • Relatively expensive to manufacture (in comparison to steel and aluminum) • Stiffness/Flexibility • Extreme temperatures ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

18. Cost Information • Vary by size and length • Range from $6.50 to $125 ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

19. Where to Buy • http://www.shape-memory-alloys.com/about.html • http://www.memory-metalle.de/html/01_start/index_outer_frame.htm • http://www.memry.com/ • http://www.smallparts.com/products/descriptions/naw.cfm ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

20. Conclusion • The many uses for these kind of materials ensures a bright future for these metals • As more projects begin to develop and utilize SMAs, the research and development will continue to grow • Advancement in SMAs will provide growth in many fields ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators