1. Haptic Display Device John MacDuffie Woodburn Michael Vitale
Thomas Santoro – Team Leader
Villanova University

2. Agenda Purpose Theory Design Testing Results Conclusions
Acknowledgements
Questions

3. Purpose
Medical Field
Console Games
Visually Handicapped

4. Virtual Reality Block Diagram

5. Theory, Active vs Passive
Active Haptic Devices
utilize actuators
forces are actively generated by actuators
Phantom Haptic Device

6. Theory, Active vs Passive
Passive Haptic Devices
the user has to apply forces to feel any resistances
Programmable Tactile Array (TiNi Alloy)

7. Theory Magnetorheological (MR) fluids
Composed of micron-sized, magnetizable particles immersed in water or different synthetic oils
(Lord Corporation)

8. Theory Magnetorheological (MR) fluids when a magnetic field is applied
(Lord Corporation)

9. Theory Magnetorheological (MR) fluids
Exposure to an external magnetic field, induces in the fluid, a change in rheological behavior
(Lord Corporation)

10. Theory Device is similar to a damper
Cylinder is used as a core for the coil of the electromagnet
Electrical current is applied to the coil
An electromagnet changes the density of the MR fluid
Stiffening of the fluid changes the resistance felt by the user as he/she.

11. Design Requirements and limitations:
Heat generation by the electromagnet
Creating an electromagnet that will affect the viscosity of the MR fluid
Simple Design for manufacturing

12. Preliminary Designs

13. Preliminary Designs

14. Equilibrium State of Design
Final Design
Equilibrium State of Design
Inside View
Outside View

15. Final Design
Design Compressed
Inside View
Outside View

16. Final Design
Schematic of a single unit
Schematic of an array of pins

17. Final Device

18. Device Working
As weight is applied the pin moves down with no applied current
As weight is applied it is harder to move the pin down as the applied current is increased

19. Testing
Achieve a characterization that will give the input-output relationship from the current/voltage to the resistance offered.
This information can be used for resistance generation to provide haptic interactions.

20. Testing Testing Apparatus Rotational Displacement Sensor Force Sensor
Haptic Device
Power Source
Movable Platform

21. Testing Procedure
Tested the device at increments of 0.25 volts ranging from 0 to 5.0 volts.
For the first run at 0 volts
Applied 0 volts to the coil
Started the Data Studio Program
Gradual raised the device up into the force sensor
Stopped the Data Studio Program
Repeat in increments of 0.25 volts till 5.0 volts

22. Testing Procedure
Collected the data into three graphs for each increment of voltage
Applied Force versus Time
Applied Voltage versus Time
Applied Force versus Applied Voltage
Based upon Applied Force versus Applied Voltage, can find the resistive force
Each increment of applied voltage will characterize the resistive force

23. Testing Parameters
Need to measure the applied force to the pin for a constant applied voltage, Fv
Need to measure the displacement of the pin for a constant applied voltage, Dv
Need to record the applied voltage for each trial

24. Data
Y=0.7936x x x

25. Data
Y= x x x+1.038

26. Data

27. Results Y=0.0625x3-0.2698x2+0.8014x+0.1248 Applied Voltage (Volts)
Applied Force (Newtons)
0.01
0.25
0.46
0.5
0.48
0.75
0.63 1
0.7
1.25
0.77
1.5
1.75
0.92 2
1.35
2.25
1.03
2.5
1.41
2.75
1.46 3
1.95
3.25
2.14
3.5
2.47
3.75
2.56 4
2.69
4.25
3.62
Y=0.0625x x x

28. Conclusion
Accomplished our goals
Able to Characterize the MR fluid for the use of Haptic Display Device
Simple part design for mass production

29. Acknowledgements Professor Dougherty - Advisor
Professor Rungun Rama Nathan
Professor Kroos
Chris Townend and Zack Nowosad
Art Viescas and Professor Vassiliou

30. Thank you for your time and have a good day
Questions?
Thank you for your time and have a good day