Simulation and VelomobilesSimulation and Velomobiles

The 2005 Great Midwestern Velomobile and HPV FestivalThe 2005 Great Midwestern Velomobile and HPV FestivalEastern Iowa Environmental Innovators Organization (EIEIO)Eastern Iowa Environmental Innovators Organization (EIEIO)

Nickolas Hein 11 June 2005Nickolas Hein 11 June 2005

Outline

Fundamental EquationsTerrain modelingResultsUsing the results

Bike designCoaching/Training

Possibilities - CurrentPossibilities - Future

Fundamental Equation Acceleration Equation for Human Power

a = F/m = [(P/W) - V2) ]*Wg

V (W/CdA)

V = Vprev + a*t

X = Xprev + V*t

Power Rolling Fric. Slope Wind Resistance

Constant Slope:

Sine-wave Hill= max* sin (2 * x / lhill) or = * sin (2x * max / h max)

where: max = Max hill slopelhill = Hill length. h max = Maximum hill height

3) Table Lookup from recorded data GPS recording via waypoints

GIS data from databases (Mapquest)Manual/auto recording

Terrain ModelingThree Methods

0.00

10.00

20.00

30.00

40.00

50.00

0 200 400 600 800

Distance (ft)

He

igh

t (f

t)

Terrain Profile

-3000

-2000

-1000

0

1000

2000

0 1000 2000 3000 4000 5000

Distance (m)

He

igh

t(m

)

-20

0

20

40

60

80

100

120

0 200 400 600 800 1000 1200

Faired

Unfaired

Results – Time History

Results - Phase Plot of Speed/Height

Results - Phase Plot of Speed/Accel

Using the Results - Bike Design

• How much can energy storage help?

• What is the tradeoff between weight and drag.

• What are the range of speeds/accels expected

• How does streamlining affect trip times?

• What is the effect of power input/timing?

• Does size (of hills) matter?

Using the Results – Coaching/Training

• Where do you get the most benefit from putting effort in?

• What is the effect of stopping partway up/down a hill?

• How much energy does turning require?

• Other?

Possibilities – Available & Underutilized

• Graphic Excel Spreadsheet

• Common engineering tools (esp. Simulink)

• Hacking flight simulations (esp. X-Plane)

• Hacking automotive simulations

• Combinations

Possibilities – Available Now

Possibilities - Future

• Custom-coded simulation using public-domain physics engine (TOKAMAK), user interface (Eclipse) and visual system (VRML).

• Cockpit hardware for rider training, design development, various studies

• Open source development centrally archived (Sourceforge)

• Similar projects are underway for aircraft (Flightgear) and spacecraft (Orbiter, Celestia). Does anyone know of something for road vehicles?

Possibilities – Future

Proposal

• Objective: Make it possible for developers to collaborate on simulation development

• Approach: Convene technical committee meeting to:– Survey the current technology– Identify simulation needs among riders, mfgs.– Publish standards for interfaces, methods, data formats– Identify emerging technologies and enable their use– Publish a newsletter to disseminate info and progress

reports.

Conclusion

• Technical Committee Meeting– Time? Place?

• That concludes this presentation.

• Questions?

Links1) www.x-plane.com, www.x-plane.org flight sim2) http://vamos.sourceforge.net/about.html – open source

auto sim (links to other similar sims)3) http://www.tokamakphysics.com4) http://www.simradar.com/Cockpit_Building/ - Flight

simulator cockpit building5)

http://www.mathworks.com/products/demos/simulink/Simulink_Key_Features/SL_R14_Key_Features.html Block diagram modeling

6) http://worldwind.arc.nasa.gov/ Global terrain and satellite photo viewer

7) Suggestions?

From CycleVision 2005