Groups of 3-4 students are given a 5-part project to design a cable supported traffic light system. At the start of the project the groups are only given a map showing an intersection where the lights are to be installed. The project parts are:

1. Scoping – students develop a list of questions that they will need the answers to before they can begin the design process. These may include the distance between the poles that support the cables, the weight of the lights, and the clearance above the road needed. A longer list of suggested questions can be found in the project file linked below. The class then pools the questions to produce an exhaustive list, and the groups then research these questions and submit their findings.
2. Cable design – students apply 2D static equilibrium at a point to calculate the tension in each cable section of the light system. The use the information gained from the scoping study as their inputs (though the instructor could aggregate answers and produce a standard set of requirements for the class). The calculations are not trivial as there are only three cables but four equations of equilibrium so they will need to adjust their geometry to get a correct solution. Students also use a cost function (based on the cable length and maximum tension) to calculate the cost of their design.
3. Cable calculations with wind loads – students apply 3D static equilibrium at a point to calculate the tension in each cable section of the light system when a wind load is applied to each light. The additional cost (due to the higher tensions) is reported as well.
4. Pole design – students return to the 2D calculations (from part 2) and calculate the pole support reactions using the 2D equations of rigid body equilibrium. They then apply a cost function based on the reaction magnitudes and pole height. Finally, groups look at ways to reduce overall cost by adjusting their design.