DESIGN OF MAGNETIC LEVITATION DEMONSTRATION APPARTUS

1. TEAM 11 WINTER TERM PRESENTATION DESIGN OF MAGNETIC LEVITATION DEMONSTRATION APPARTUS Fuyuan Lin, Marlon McCombie, Ajay Puppala Xiaodong Wang Supervisor: Dr. Robert Bauer Dept. of Mechanical Engineering, Dalhousie University April 4, 2014 http://poisson.me.dal.ca/~dp_13_11

2. Presentation Overview • Project Description • Design Requirements • Product Architecture • Component Selection • Conceptual Design • Design Alternatives • Chassis Design • Control System • Plant Subsystem • Circuit Design: Amplifier & Driver • Controller • System Implementation • GUI • Budget • Assessing Requirements • Future Considerations

3. 1. Project Description • Design and build a magnetic levitating device • To levitate an object magnetically • Demonstrate different control theories taught in MECH 4900 Systems II course Object Levitating Arduino (MCU) & Circuitry for Levitation

4. 2. Design Requirements • Demonstrative Requirements • Levitate object magnetically • Compare simulated and experimental position of the object being levitated • Lag, lead, lag-lead P, PI, and PID control • User Requirements • Graphical User Interface (GUI) to interact with device • Plug ‘n Play • Safe and Ergonomic

5. 2. Design Requirements • Visual Requirements • Viewable from 15- 20 ft. (back of the classroom) • Levitate the object at least 2-4 cm away from the coil • Power Requirements • Conventional 120 VAC input • No potential electrical risk to the user • Operating Budget $1,500

6. 3. Product Architecture General Schematic of demonstration device

7. 4. Component Selection Table shows selected components of the subsystem

8. Electromagnetic Levitation • Strength of magnetic field generated by the coil depends on the current supplied • Control challenge: Electromagnetic Levitation

9. 5.1. Design Alternatives 2. Double Electromagnet Design 1.Single Electromagnet with Hall Effect Sensor 3. Multiple Coil Parallel Arrangement

10. 5.2. Chassis Design Design evolution of the chassis Material options for the chassis

11. 6. Control System Input Error Current Actual Position Controller Plant + _ Desired Position Unity Feedback System

12. 6.1. Plant Subsystem Voltage Output Current Position Change Sensor Levitation Breakdown of the Plant System

13. Electromagnet Design Requirements Air Gap, X = 20 mm, Object Mass = 20 g, Coil Turnings, N = 1000 For pole D = 3 cm, A= =0.00071 Permeability of free space,

14. Electromagnet Selection Assessment of 12 VDC Pneumatic Solenoid based on design requirements

15. 6.1. Plant Subsystem Voltage Output Current Position Change Sensor Levitation Breakdown of the Plant System Hall Effect Sensor

16. Sensor Component • Hall Effect Sensor • Analog position sensor (Solid State Type – SS49 Series) • Size: 30 x 4 x 2 mm • Range of Detection: up to 4 cm • Unit Cost: $2.50 Picture Courtesy of Honeywell.

17. Design Refinement Final Design Initial Design Addition of new Hall Effect Sensor to differentiate Electromagnet signal

18. Sensor Testing

19. Sensor Circuit Design Circuit for Differential Amplification of Sensor Ouput

20. 6.1. Plant Subsystem Current Sensor Measurement Sensor Calibration Voltage Output Position Change Levitation Actual Position 2 Hall Effect Sensors

21. Position Sensor Calibration

22. 6.3. Control System Input Error Current Actual Position Controller Plant + _ Desired Position Unity Feedback System

23. 6.3. Controller Component • Microcontroller - Arduino Mega 2560 • 4 – Hardware serial ports for communication with MATLAB • Runs control algorithms • Cost: $55 Picture Courtesy of Arduino

24. 7. System Implementation Receive Data Serial Communication Levitation Control • Arduino & Real Time • Arduino uses feedback data from sensors to manipulate position • MATLAB & Arduino • Manipulation of control parameters • Retrieval of feedback data

25. 8. PID Controller

26. 8. Budget Summary of Materials Cost

27. 8. Budget Summary of Budget < $568 Approved Budget

28. 9. Assessing Requirements • Demonstrative Requirements • Levitate object magnetically • Compare desired and measured controller variables • Lag, lead, lag-lead compensation techniques • P, PI, and PID control • User Requirements • Graphical User Interface (GUI) to interact with device • Plug ‘n Play • Safe and Ergonomic

29. 9. Assessing Requirements • Visual Requirements • Viewable from 15- 20 ft. back of the classroom • Levitate the object at least 2-4 cm away from the coil • Power Requirements • Conventional 120 VAC input • No potential electrical risk to the user • Operating Budget $1,500

30. 10. Future Considerations • Build more powerful electromagnet or add an extra electromagnet to repel the levitated object – Might increase the range of levitation. • Implementation of lag, lead, and lag-lead compensator. • Use different microcontroller capable of serial or other form of communication without effecting the frequency of the feedback signal. • Use different interface instead of MATLAB for example LabView

31. Acknowledgements Dr. Y.J. Pan Mechanical Dept. Professor Dr. Timothy Little Electrical Dept. Professor Al-MokhtarO. Mohamed Post-Doctoral Position Mech. Dept. Jonathan MacDonald Electrical Technician Angus MacPherson Mechanical Technician Reg Peters Wood Workshop Technician

32. Thank You & Questions?

40. References Arduino UNO webpage. http://arduino.cc/en/Main/arduinoBoardUno. Retrieved Mar. 30, 2014 ATmega238 datasheet. http://www.atmel.com/Images/doc8161.pdf. Retrieved Mar. 30, 2014 Honeywell SS49 datasheet. http://www.wellsve.com/sft503/Counterpoint3_1.pdf. Retrieved Mar. 30, 2014 "RobotShop : The World's Leading Robot Store." RobotShop. N.p., n.d.Sun. Mar. 30, 2014 “MathWorks MATLAB/Simulink website.” http://www.mathworks.com/products/simulink/. Retrieved Mar. 30, 2014 Mikonikuv Blog, “Arduino Magnet Levitation – detailed description.” http://mekonik.wordpress.com/2009/03/17/arduino-magnet-levitation/. Retrieved Nov. 20, 2013 Williams, Lance. "Electromagnetic Levitation Thesis." N.p., 2005. Web. 28 Oct. 2013.

41. Control System Question

42. System Model , A Ball Model: • Force Balance • Electromagnetic Force • For change in position, • Thus, the differential equation: Inverse Square Law! Static equilibrium: Magnetic Plant Constant: Linearization of electromagnetic force using Taylor series approximation: = =

43. System Model Electromagnet Model Inductance Reactance Electromagnetic coil driving circuit

44. System Model 87 mH, • Electromagnet Model Laplace transform: Rearranging the equation Finally, : Simplified Circuit

45. Control Systems Electromagnet Plant (Levitation) Voltage Input Position Change Ball Combination of Electromagnet & Ball Model Thus, the uncompensated system Note: Negative controller gain is required