Coming from an RC sailplane background, the task of planning system wiring on a multirotor can be a bit daunting. With sailplanes, all one has to deal with are servos, rx & battery; with multirotors, and in particular, this one we have:
- Spektrum AR9020 DSMX Receiver with 3 Satellite Receivers
- Spektrum TM1000 DSMX Telemetry System with Voltage & Temperature Sensors
- DJI Wookong M Main Controller
- DJI Wookong IMU v2
- DJI Wookong M PMU (Power Monitoring Unit)
- DJI Wookong M GPS Puck
- DJI iOSD (On Screen Display)
- DJI 5.8ghz Video Transmitter
- DJI Bluetooth LED
- Gryphon Dynamics Power Distribution Board (PDB)
- Gryphon Dynamics Power Disc Dual BEC
- 8 Maytech 75 Amp Brushless ESCs with SimonK Firmware
- 8 Castle Creations CC CapPacks
- 8 Tmotor U7 490kv Motors
Not to mention all the components that will be on the camera gimbal!
So, if you’re like me ( and hopefully you’re not! ), one spends a lot of time just standing and staring at all the components, pre-organizing how all the components will be arranged on the airframe. That is what this post is all about so let’s take a looks at version 1 of my center frame components layout…
Component Mounting Philosophy
One can get caught up with trying to hide as many components and wires as possible for a clean look. My approach is to provide a clean installation while still giving quick access for key components. Really, unless one is trying to develop a water resistant / proof platform, there is no need to hide components that you would otherwise need quick access to.
As stout as GD’s frame are, they are surprisingly light which is great as at the end of the day, a lighter MR stays in the air longer. Much of this is due to all the lightening holes in the carbon plates which is great also for giving you plenty of options for wire routing. My only concern is that there are not solid slabs of carbon to mount the IMU or GPS. As you know, if the IMU were to come loose, you’re nice day of flying would turn into a sad night of weeping! That said, there is probably sufficient material for the double sided tape to adhere to. Just to be safe, I’ll be adding additional points of contact either with zip ties, velcro straps and/or dabs of hot melt glue.
Another nice thing about this frame is how quick it is to assemble. It does have a bunch of screws as some have pointed out in this thread but not any more than I personally find reasonable. A nice touch is that there are pass-through holes for your allen/hex wrench where needed for frame bracket screws and such.
Even though DJI’s iOSD Mark II provides voltage telemetry to the one looking at the camera, I’m often finding myself yelling to the camera operator (Phil in this case!) “What’s our voltage?!”. For less yelling and more peace of mind, I’ve decided to run telemetry via Spektrum’s TM1000; specifically pack voltage and temperature. I’ll run the temperature sensor first in the arms to make sure the ESCs aren’t getting too hot. Later we may monitor the temp of other components such as batteries.
As you can see in the picture, the TM1000 fits perfectly in one of the landing gear supports! I simply wrapped it in foam and slid it in for a no-slide fit. The wires then have a perfect exit point right at the center of the frame.
Instead of waxing poetic on the rest of the instal, I’ll let the pictures do the “talking”. If you have any questions, comments or suggestions please feel free to add them to the discussion below!