Most of the parts that make up this quadcopter were created using the 3D printer. The list of parts with their respective stl files are shown below.
|Battery Clip||B&S Mount 1|
|B&S Mount 2||MCU Mount|
|Motor-Fan Mount||Motor Mount|
Troubleshooting the 3D Printer
Several issues occurred when printing parts with the 3D printer. The first issue was that the plastic protector belt on the platform became warped after several printing jobs. This would cause the bottom of all the parts to have creases and bends.The issue was resolved by removing the belt completely and replacing it with aluminium foil and Kapton tape. The Kapton tape was used because the ABS plastic would not adhere to the aluminium surface.
The second issue encountered was when the printer head starting to sag. After many prints, the platform weight of the platform head started to misalign in the z axis. This is caused by the stepper motor having insufficient strength to lift the platform, causing missteps: parts printed when the printer was in this state have inconsistent heights. Adding a counterweight to support the printer head platform prevents the head from sagging and results in more uniform prints.
Another issue that consistently occurred was the uneven dispensing of the initial layer and the lifting of plastic. This occurred more often in large parts and caused major warping. Many factors contribute to this occurrence – the calibration of the extrude head, among other things – but the major cause is the temperate variation when the part is cooling. At the moment there is no solution to this issue but it is possible to reduce the number of defects by heating the platform externally (for example, with a hair dryer).
For the safety of the craft and of those around it’s flight zone, we wanted to build some sort of protector around the quadcopter. The CAD model that was drawn for the Styrofoam protector was converted into a template which was then used to trace the lines where the Styrofoam needed to be cut. The circles and curves were drawn using a compass device with a Styrofoam cutter attached to the end.
One of the problems of using Styrofoam as the protective encasing is that Styrofoam is very brittle and is prone to snapping during sudden impacts. After experimenting with different methods of strengthening this material, it was found that covering the material with tape greatly increases its strength and flexibility.
In the quadcopter design, the micro-controller is placed on the top (highest level) of the craft. This leaves the micro-controller and its circuitry exposed to physical damage. Using the bottom of a 1L club soda bottle, a protector cover was constructed to protect these vulnerable electronics. An additional bonus to this design is that the cover creates a flat surface for the craft to rest on when doing modifications underneath!