The Aerodynamic system allows us to travel at higher speeds without using too much power. Over 60km the drag force becomes much strong then rolling friction. The mirrors are not very aerodynamic and travelling at high speed without stowing them would quickly use up our solar power.
My initial design is to have a series of doors that will cover the mirror to make them more aerodynamic. The rear section of the trailer will also be covered to form a tapered shape. This shape reduces the vacuum behind the trailer which greatly the drag. The aims is to have the trailer frontal profile the exact same as frontal profile of the car to not add any profile drag. Then if the rear section is more aerodynamic then the rear of the car it is possible that the car and trailer would be more aerodynamic then just the car by itself. The problem is the added weight and complexity of all these doors (see weight and cost budget). It is also important that all doors are strong and secure to prevent the doors from flying off while the car is travelling on the highway. CFD, computer aerodynamic simulations will reveal an approximation of the drag at different speeds between the covered mirror and open mirror designs. This will then be compared to the approximate weight increase of the extra doors.
The one mirror trailer test unit will then be used to get real drag numbers. I will start by building only the rear mirror with the aerodynamic taper up against the back of the car. I will drive at different speeds with the mirror out and the mirror stowed with taper. I will be able to measure the power the electric drive motor uses for each case, using the Arduino controller.
The rear mirror will also need to have removable rear corners so it can fit inside the taper doors. The centre sections of the mirror will remain attached to the pipe and only the rear corners will be removed. They will be bolted on in a way that does not effect their optical accuracy when they are removed and reinstalled.