A two part updated today. After last working on my concept layout I was without an internet connection (modem failure) to publish my progress.
First up I started fleshing out an idea for power distribution. This idea being a single PCB with all 5 of the ESC’s and a battery connector soldered directly to it. Currently I have not looked at the electrical feasibility of this at all and I expect it could be challenging given the high currents being dealt with. That said other similar sized copters have implemented the same concept successfully. One possible downfall of my approach is trying to do to much in to little space. Complications (read challenges) I have introduced include:
- ESC’s on both sides of the board, this might make a simple one side +ve the other -ve approach more difficult.
- Bullet connectors included on board, individual traces will be required rather than simple +ve and -ve planes.
- 100mm length limit as this is the large size offered by http://dirtypcbs.com/
- XT60 connector directly soldered to the PCB. This may in fact be a very bad idea a for reliability, a loose battery may tear the connector from the board and fixing that will not be a quick swap without another fully populated power distribution board (5 ESC’s!) ready to go.
In any case getting this concept for power distribution together has meant that I have shuffled the overall layout about again. The power distribution board itself has been dropped low and pushed forward beyond the front boom. The fuselage structure will need to extend forward to protect this. The thrust vectoring servo’s have been repositioned in a vertical orientation in an attempt to keep the fuselage narrow, servo horns were added for a more complete picture.
The next development was to create the first draft of the motor mounts. The concept here is that the motors would first be attached to the mount before the mount is subsequently attached to the arm with its opposite number. I intend to add extra fasteners at the tips of the arms to hold the two halves together. I also need to add some thickness below the motors so that the two halves support each other at the tip whilst leaving a gap at the back end so that the two halves clamp on to the carbon tube.
Whilst the layout hasn’t changed markedly here it does illustrate what the motor mounts look like installed. An entirely different solution will be used for mounting the rear motor.