This is SCOE Robotics Demo quadcopter that was built during the 2011-2012 school year. This is mainly used for fundraising and campus events since it is small and very easy to transport.
For the demo robot we wanted a simple frame that could be built for cheap. We ran across this design thread on rcgroups.com and we liked the idea of frame made with just sheet plastic or wood.
http://www.rcgroups.com/
Our demo quadcopter is slightly different than the design on the rcgroups thread. For one, we decided to use 1/8in acetal delrin cut on a cnc router for the frame. Our frame is also larger with a motor to motor distance of 13in as opposed to 8in in the forum design. This was done to accommodate the larger props that we already had.
Our first design used a single layer of delrin for the arms and hub structure. Our first flight test showed that our motors caused a resonance issue with the derin and the arms would deflect almost 1/2in at about 30% throttle.
We redesigned and changed the arms to two layers of delrin with foam between layers to help mitigate vibration. We also added grommets to the electronics mounts and vishay grommets to the actual controller board. This helped to greatly reduce the amount of vibrations the controller registered. We are using the HoverFly quadcopter controller that was won at the 2011 CARD Competition. While it is a professional and reliable controller, its completely closed source. There is no possibility of adding our own accessories or flight modifications.
The quad had limited flight success. We are still having trouble with these Turnigy motors. The windings keep burning out and the bearings are starting to go. We will have to change these out soon.
If anyone has any questions post them here and we will do our best to answer them. Good luck with your own designs and I hope to see more flying quadcopters on this forum soon.