Texas A&M EPICS transportation Services team

1. Engineering Projects
In Community Service
Fall 2010 - Transportation Team
Lauren Stanhouse ’11 Michelle Havlock ’11
Ryan McCarthy ’11 Marcus Fisher ’13
Danielle Egbert ’11

2. EPICS
Fall 2010 - Transportation Team
Lauren Stanhouse ’11 Michelle Havlock ’11
Ryan McCarthy ’11 Marcus Fisher ’13
Danielle Egbert ’11

3. Texas A&M University
✤ Transportation Services Mission Statement: Transportation
Services is an empowered team of professionals dedicated to
providing efficient, dynamic and innovative fleet, parking and
transit services to the community. Transportation Services
supports the teaching, research and public service mission of
Texas A&M University, with focus on customer service and
communication
✤ Smart Energy Campus Initiative: A collaboration of
departments within the University system created to establish
and promote “green energy” solutions throughout Texas
A&M University.

4. Our Mission
✤ The EPICS Transportation Team, in coordination with Texas A&M
Universities’ Transportation Services is a group of student engineers
dedicated to the sustainable practice of engineering foundations to
develop community service projects. We promote the University and
it’s subsets mission values with focus on serving the community of
students through Transportation Services.

5. Energy Harvesting Speed Bumps
✤ How can on-campus traffic be utilized to
gain the University goal of LEED
certification?
✤ Design a system to harvest energy from vehicles on campus to
supply electricity to gate systems without impeding the flow or
direction of traffic

6. The Design
✤ A plateau consisting of a series of modulated speed bumps that
convert horizontal motion into rotational motion in order to
generate electricity
✤ Light weight, high grade materials that allow for semi-
portability
✤ Modulated design allows plateau to be lengthened and/
or widened to fit traffic constraints

8. The Big Picture
✤ Using a low RPM,
permanent magnet Direct
Current generator
✤ Operates within 500
Revolutions Per
Minute
✤ Monetary Generation
of up to $14,000 per
year
* Assuming 500 RPM over a 16 hour primary operating day

9. The Mechanics
✤ Mechanical Design
✤ Fluid Dynamic Design

10. The Mechanics
✤ Mechanical Design
✤ Fluid Dynamic Design

11. Mechanical Design
✤ Direct drive, low RPM permanent magnet generator (0.5 eff)
✤ A stationary ball-screw linear actuator is rotated by vertical
translation of the speed bump. The xy-planar rotation is
transformed to xz-planar rotation using a right-angle bevel gear
which directly drives the gear with ratcheting mechanism and
generator
✤ Individual units of external-gears attached to ratcheting
mechanisms are linked in series by a chain to the primary gear
driving the generator

12. Single Unit

13. Single Unit
Series of Units

14. Comparison
✤ Advantages: ✤ Disadvantages:
✤ Higher efficiency energy conversion ✤ Requires custom parts
✤ Capable of achieving 500 RPM for ✤ Mechanical components
optimum generation require more frequent
maintenance
✤ Allows synchronous movement of
multiple units on ONE generator ✤ Open system must be
protected from weather and
unanticipated impact

15. The Mechanics
✤ Mechanical Design
✤ Fluid Dynamic Design

16. The Mechanics
✤ Mechanical Design
✤ Fluid Dynamic Design

17. Fluid Dynamic Design
✤ Micro-turbine driven, low RPM permanent magnet generator
(0.3 eff - 0.5 eff)
✤ Fluid transfer from a compressible volume to an adjacent
chamber through a tube containing a micro-turbine
✤ Closed system design

18. Fluid Dynamic Design Sketch
Micro-turbine housed within air release valve that turns shaft of generator.

19. Design Parameters
✤ The compressible volume is held under a confining pressure
prior to impact
✤ Assuming 1/2 the compressible volume is transferred upon
impact
✤ Power Generated (per car): 870 W
✤ Power Harvested: 26.1 kWh
* Power harvested accounts for the assumed 0.3 and 0.5 efficiency of the turbine and generator
respectively.
* Power harvested calculated using max University gate traffic patterns over a 16 hour operating day.

20. Comparison
✤ Advantages: ✤ Disadvantages:
✤ Closed system operates independent ✤ Requires an independent
of weather generator for each unit
✤ Fewer mechanical parts requiring ✤ Power output under optimum
maintenance operating conditions (5.87
kWh) is less then estimated
✤ System is fully modulated and acts mechanical design output
independent of other units
✤ Mechanical failure due to gas
lock within the system may
require extensive
maintenance

21. The Right Choice
✤ Mechanical Design
✤ 500 RPM is achievable
✤ Higher power output (≈ 30 kWh)
✤ Lower unit cost because of shared generator
✤ Maintains modulated design in order to adapt to traffic constraints

22. The Next Steps
✤ Finalize mechanics with a mechanical engineer to ensure the safety of
operators
✤ Dimensionalize custom parts
✤ Update speed bump design to account for proper height
displacement of mechanical components
✤ Outsource manufacturing
✤ Implement across campus