Section 1.0 Project General Description

Team Human Power

Taylor Brown, Kyle Chapman, Adam Cooper, Jamie Huffman, Joey Stine, Matt Strand, Tyler Jandreau, Kevin Villa and Jimmy Woodard.

1.0.1 Project Preface

This section is designed to give the reader a tangible ‘mind’s eye’ representation of the vehicle. It is, in essence, an aerodynamic bullet with a bicycle inside. The rider, James Woodard, is lying (or sitting at a very shallow angle) for maximum aerodynamic efficiency. To maximize the speed, the shell is aerodynamically analyzed to produce the smallest amount of drag, lift, turbulent wake, etc.

Figure Above: The final representation of our Human Powered Vehicle. Ours should look similar to this. [1]

The bicycle inside is custom and its design is up to the discretion of the team. All (or most) components will have to be fabricated by the team, including a way to steer and stop the vehicle.

The nature of this vehicle is unique. It provides the students working on this project integration into many different types of engineering such as aerospace, mechanical and composite engineering. It also involves the human body and the athletic power that it can produce. The students will be required to enhance the current methods and technologies used in Human Powered Vehicle design.

1.1 Describing The Project

Team Human Power is comprised of several students from various engineering backgrounds. The common goal is to design and build a vehicle that can break the collegiate land speed record of 61.5 mph. Because of the complicated nature of this project, it is necessary to break down the requirements of the work. They are as follow:

Aerodynamics to maximize the flow around the shell
Aerodynamic analysis to ensure there is to lift on the vehicle at speed
Structural Dynamics to analyze the forces and moments on the frame
Vibration Analysis to ensure the vehicle is stable at speed
Fabrication of parts with materials such as:
Carbon Fiber
Aluminum
Steel
Rubber
Fiberglass
Designing Auxiliary systems which include:
Steering linkages/systems
Rider viewing area (periscope, bubble)
Brakes which stop the vehicle in a controlled manner
Analysis of athletic output for a seasoned athlete

All the previous factors will need to be addressed to make this project a success. Because of the limited amount of sustainable power from a human (0.2 kW or 0.25 horsepower), this machine will have to be very well designed to reduce the amount of lost wattage. All the power our human rider can produce will be channeled into propelling the vehicle forward.

This project is also unique because of the complexity of the systems. The shell dimensions will have to be as close to Jimmy’s shoulders as possible and allow him to see easily. The length will be governed by the HPVA (Human Powered Vehicle Association) rules for the 2008 year, but this value will most likely be eight feet. The shell will be comprised of a single layer of carbon fiber, which was laid up in a mold that was previously constructed. The shell will have to be at least partially removable to allow easy access to the rider.

The frame will also be constructed of carbon fiber or fiberglass, depending on the cost of the material at the time of purchase. It will be fully analyzed both by hand and computer tools to ensure the safety of the frame. A factor of safety of at least 1.5 will be used (aircraft standard) for strength and lightweight construction. The composite nature of this frame will allow for ease of construction. Because none of the team members are yet machine shop certified, the experimentation with composites will be up to the discretion of the team.

The drive train will be a hybrid construction of a pulley/belt system and a conventional bicycle chain system. There will be a cassette (group of sprockets or gears) and accompanying derailleur for ratio control. The team members calculated the ratio needed to achieve the 61.5 mph goal. Different ways to obtain the ratio were investigated which will optimize human power output.

1.2Completed Work

This is an abbreviated list of the work that has already been completed

1.)Complete literature review to obtain basic concept of the Human Powered Vehicle

2.)Determine the safety of the shell by analyzing puncture strength and abrasion resistance of various carbon thicknesses and weaves

3.)Complete feasibility document which compares our available human power to the required power to achieve 61.5 mph

4.)Take measurements of our rider for geometric considerations of the frame

5.)Importing the dimensions from Jimmy to Pro|E and design the initial frame

6.)Design the drive train and optimize the ratio for maximum rider power output

7.)Crudely fabricate the frame and drive train to test calculations

1.3 Future Work

This is a rough representation of the future work, but is greatly simplified to save space.

1.)Build an aluminum frame as a testing mule

2.)Transfer drive train components from wooden frame to testing mule

3.)Begin designing and optimizing shell

4.)Complete optimization of shell

5.)Complete design of final carbon fiber shell

6.)Create mold for shell (complicated process with many subsets)

7.)Create mold for frame (complicated process with many subsets)

8.)Lay Carbon for both models

9.)Final Assembly

1.4Material Testing

There is not any remaining testing to be done that involves composites. We know the strength of the composite shell because of testing completed in Aerospace Structures Lab. The only remaining testing to be done can be completed by hand for the composites.

We also know that the aluminum will not need to be tested due to the literature that is available to us. The strength properties of this material is already known and accepted widely, so no further materials testing should be completed.

1.5Vehicle Testing

There is a substantial amount of vehicle testing to be completed because the vehicle is not constructed yet. There will need to be vehicle testing because of the nature of the vehicle itself. The drive train will have to be tested through integration to the frame, and the frame will have to be tested with the rider. Most importantly, it is necessary for our rider to experience piloting this vehicle at low speeds before attempting the land speed record. Also, the low speed vehicle tests will allow the rider to familiarize himself with control, braking and stopping.

High-speed tests will also need to be completed with the fairing, but that is generally considered dangerous. Team Human Power will attempt to replicate high speed testing through several low speed tests.

1.6 References

[1]