A function structure is a tool to show the flow of materials, energy and information within a system. The material flow represents the device, the energy flow is how the device is powered, and the information flow is what controls the device. A complete function structure should have a clear boundary, with both inputs and outputs crossing the boundaries, and it should show where material, energy, and information flows intersect, demonstrating how they interact with one another. Furthermore, a function structure must be solution neutral, and sub-functions must be represented by verb-noun tuples. Figure 2.1 below shows Team Breaking Wind’s function structure for Project WindBAG.
The inputs for our function structure are of course material, energy, and information. To simplify, we essentially need to create a device which will then take those inputs, collect wind, convert it and store it in another form of energy, and use that energy to create torque which moves the device. Collecting the wind and converting it to another form of energy will cause the wind, a material input, to interact with the energy flow, as it is converted to usable energy. The torque will then power both the “drive forward” and “navigate track” verb-noun tuples. As the device drives forward and navigates the track, it will constantly need to read data in order to know how to maneuver next, so the material and information will need to work in tandem. Lastly, heat and noise will leave the system boundaries as waste as a result of converting energy and torque.
This function structure is feasible because it satisfies all the components of the problem statement; it is able to collect wind, convert it to another type of energy and store it, and use that stored energy to navigate the track for at least one lap. Moreover, this function structure does not add any unnecessary complications to being able to carry an additional payload and does not create any conflicts with the requirements list.