Crouching Tiger Hidden Car

The AIChE (American Institute of Chemical Engineers) ChemE Car competition is an annual event that challenges student teams from universities around the world to design and construct a small, chemically-powered car. The primary objective of the competition is to develop a vehicle that can carry a specified load of water as close to a final distance, given on the day of the competition, that is solely powered by a chemical reaction. The car stop must also be controlled by a chemical reaction. Our submission, the "Crouching Tiger Hidden Car" is powered by student developed alkaline batteries which implements the chemical powered requirement of the competition. This provides a stable power source for the motor for predictable velocity and travel time. The car stop is controlled by a vitamin C iodine clock reaction. This reaction has predictable kinetics (rate of reaction) and a very distinct and sudden color change. On board, we have an LED shining through the solution which is detected by a photoresistor. Once the LED light is "dimmed" by the color change in the reactor solution, the photoresistor value is read and compared to a threshold value to stop the car. Thus we can control the distance of car travel through solely input reactants. In our exhibit, we go over the trial and error tribulations of developing the car including manufacturing of the custom components as well as the governing theory of the car operation. This includes a delve into the car electronics and chemistry of the batteries and stopping reaction to describe how we are able to use these to create a predictable car travel distance.

3D printing the stopping reaction chamber.

Electrochemical testing on student-made batteries.

Snazzy group photo