The priorities of building the UAV frame are to make as light as possible and as strong as possible. Reduced weight helps the quadrocopter to be more agile in the air. It increases also the battery life and therefore the overall flight time. However, the increased durability of the structure makes it more rigid and immune to damages.
The first step to achieve above goals is to find and choose the best possible material. It would have to fulfil below conditions:
From broad selection the special aluminium composite has been chosen. It consists of two layers of Aluminium and one layer of Polyethylene in between of them. It is fairly easy to cut it and form it but most importantly, it is very light and strong.
The second step is to create initial drawing of the whole construction and then redraw it again in the one of the special CAD applications. One of the biggest difficulties is to make all the measurements right, so each part will fit to the whole construction.
The CAD application was used not only to make more clear vision of how the future vehicle will look, but mostly to provide all the data needed for CNC cutter to produce perfectly matched, real copies of the designed parts.
Final stage of building the construction of the flying model is to put all the parts together. With some corrections made to the prototype all the parts fit together.
With some corrections made to the prototype all the parts fit together. With two tone colour the machine already looks very neat. In the picture below, final version of the frame with mounted engines.
