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Testing the  Superbike Superbike - home

At each stage the bike was extensively trialled with wind tunnel experiments, strength assessment and test riding by Australia's elite cyclists. A major aim of testing is to show that less power needs to be generated by the cyclist to move the Superbike at a particular speed compared with a conventional bike.

Activity
Read the following paper
Engineering the world's fastest bicycle to find out more about the testing carried out. This paper is suitable for students of engineering studies.

See the Milestones in design development for a summary of the paper.

Testing techniques explained
Wind tunnel testing

Activity
Look at the photo of the artificial legs rig used in wind tunnel testing; then read the passage below, summarising the information into points, for example:

  • artificial legs used to simulate rider
  • rider's legs influence flow pattern and drag
  • rear wheel driven by motor…

In order to minimise aerodynamic drag, new and innovative wind tunnel testing techniques were developed. This included the use of artificial legs to accurately study the airflow over the bicycle. With this unique rig the aerodynamics of the complete system could be represented.

Initial investigations showed that the rider's legs dramatically influenced the flow pattern and resulting drag. To obtain accurate and repeatable wind tunnel results with live athletes was extremely difficult. The sensitive wind tunnel balance required precise knowledge of the centre of mass in order to apply corrections for induced forces due to moment couples. In the development of the 'Superbike' the rider was replaced with a pair of lightweight Styrofoam® legs. A similar lightweight torso, head and arms could also be fitted. The rear wheel was driven by an electric motor beneath the wind tunnel floor. A simple belt drive under the floor also drove the front wheel. By having the motor and drive system part of the bicycle accurate and repeatable drag measurement was possible. (Thompson, 1996: 2)

Finite element modelling (FEM)
Activity
Look at the FEM diagram and read the explanation of the diagram below.

The FEM diagram in the article illustrates how load is distributed throughout the monocoque shell. Prototypes were modified using data from:

  • the mathematical performance model
  • the testing of properties and materials
  • the track tests and race data of athletes.

Maximum load is indicated by shades of red, minimum load by blue. In this image of a prototype the greatest load is in the curved section of the shell.

Activity

1. Identify another area of performance design that might use FEM during development and prototype testing. Remember, the performance goals were:
  • optimising weight
  • frame stiffness
  • aerodynamics.
2. What is the information gathered by FEM used for?
Refer to the Milestones in design development and Engineering the world's fastest bicycle
.

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