 |
| Figure 1: ArduPhantom Night Flying |
The DJI Phantom has some nice air frame features: A sturdy plastic injection molded polycarbonate enclosure that keeps out light rain and resists hard impacts very well; Nice motors with simple, easy to use prop-mounts that are very unlikely to come loose in flight or get bent or broken in a crash; and very light-weight ESCs that have super bright LEDs on them for easy visual orientation at great distance, and superb night flying (Figure 1).
I also wanted a very small, lightweight, and extremely rugged FPV platform that I could carry in my backpack when I go hiking. The DJI Phantom air frame seems perfect for this, as the propellers are extremely easy and fast to remove, and once removed the rest of the aircraft can be stuffed in my backpack as is, and is sturdy enough to not worry about it being damaged during the trip.
But, since I'm a fan of ArduPilot, and like to be able to perform complex auto missions and make modifications to the code, I decided to build a DJI Phantom air frame with an APM flight controller. The result was very successful, and I encourage you to do the same, following the instructions below.
Materials
For this build, you will need the following parts. Fortunately, the DJI replacement parts needed can all be purchased quite cheaply. My budget for this entire project was about $600.
1x DJI Phantom replacement case kit
1x DJI Phantom replacement screw kit
1x DJI Phantom connectors kit
2x DJI Phantom ESCs (green)
2x DJI Phantom ESCs (red)
4x DJI Phantom motors
2x DJI Phantom props (set of 1 CCW and 1 CW)
1x DJI Phantom landing gear
1x APM 2.5
1x 3DR Power Module
1x 3DR GPS module
Power System Wiring
First you'll need to mount the ESCs and motors in the case, and wire up the ESCs to the output side of the power module. When mounting the ESCs, be sure the green ones are at the front end of the aircraft (the battery door end), and the red ESCs in back. If you put the red ESCs in front instead, then the signal leads won't reach, because they are of different lengths.
There is not much space inside the case for a lot of wiring and connectors, so I just cut off the XT60 connector from the output side of the APM power module, and soldered the connection directly, insulating with heat shrink of course. If you plan to use an internal battery, make sure the wiring doesn't cross over the central area where the battery goes, because it will snag on the battery when you take it in or out, and it's already a fairly tight fit for the battery as is.
Also, be sure to keep all the wiring as low in the bottom of the case as possible, so the magnetic fields from high-current wires will not interfere with the autopilot's magnetometer (Figure 2).
 |
| Figure 2: Power Module and Power System Wiring |
Mounting APM, GPS, and RC Receiver
At first I velcro mounted the autopilot, GPS, and receiver to a thin wood plate which I screwed on to the four screw bosses protruding from the case bottom. This held it high enough above the power wiring below to avoid magnetic interference. However, I found that this piece of wood was basically a sounding board for vibration. Even adding foam between it and the autopilot wasn't enough to reduce the vibration to a reasonable level to get good accelerometer readings (Figure 3).
 |
| Figure 3: How NOT to mount your APM |
Later I found that a soft plastic cottage cheese lid made of Low-Density Polyethylene (LDPE) is a great way to mount the APM, since the soft flexible material helps to dampen vibrations (Figure 4).
 |
| Figure 4: APM mounted on LDPE food lid greatly reduces vibration |
Once you get the case on you won't want to remove those 16 screws every time you need to upload the latest version of ArduCopter, or download a flight log. So you should probably make a short USB cable that permanently connects to the APM, as shown connected in figures 3 and 4 above.
LED Connection
You won't be able to see the status of the armed and GPS lock LEDs once the APM is enclosed in the case, so you'll want to connect a couple external LEDs that you can view through the tail light port on the Phantom case. Connect one LED to A4 and one to A6 (you can also connect a buzzer to A5 if you want). Signal goes to the + side of the LED, and ground to the - side. Remember to include resistors in series with each LED to drop the voltage to the proper level for the LEDs you are using (Figure 5).
 |
| Figure 5: Armed and GPS fix LEDs visible through tailight port |
You'll also need to go into Mission Planner and change the LED_MODE to 11 (the default is 9 for some reason).
Final Assembly
You can now put the top of the case on (attached with the twelve M2.5x5 and four M2.0x8 screws from your screw pack). Once you calibrate and configure everything in Mission Planner then you should be ready to bolt on the props and go fly (Figure 6)DJI phantom
 |
| Figure 6: Ready to Fly |
Flight Testing
I added a GoPro, a 5.8 GHz video transmitter, and a 3DR telemetry module for some FPV flying during a Sunday hike in the mountains. Here's the results of the first test:
It flies very nicely, even in auto modes. The main issue is shakiness and vibration of the recorded video. Hopefully I can reduce that with some tuning, better camera mounting, and perhaps stiffer props.
Comments
Thanks for replying. I tried it but still won't work. I set it to "Fast" and even adjusted the THR_MIN to 155 but still didn't help. I can only see motor spinning after I applied some throttle. It's like the new parameters didn't even use at all.
You may need to increase the MOT_SPIN_ARMED parameter so it's giving the ESCs enough PWM in idle to keep the motors spinning.
I just finished putting APM on my phantom. My APM firmware is 3.1 but somehow when arming, the propeller will not spin until I put some throttle. Anyone having the same experience? Is it normal? The same APM when I used on other ESC will spin motor on arming.
given some of the interview comments by the ceo of dji it doesnt look like this hybrid build can be pulled with the new dji phantom vision at least not just yet(of course all bets are off after the first one is" crashed" and pulled apart on the bench). :)
BUT the other question in my my mind is how fast will replacement upper and lower shells and the rest of the repair parts for the vision be available just in case some one wanted to attempt same.(arducopter swap into a souped up vision airframe and try tackling writing the interface to the vision cam from the arducopter code
hzl
I guess twisting might have some slight advantage over just putting them tightly side by side, but it would require longer wires and more weight and space. A donut toroid would not do anything for reducing your magnetic field interference though; for the magnetic field, which is what affects the compass, it's all about the enclosed area of the current loop.
Yes, I put the 3DR telemetry module inside the Phantom case as well, although to get it to fit I removed the plastic cover from the antenna.
Yeah, the FrSky Taranis looks like amazing value for the money at least.
really thinking about cancelling the y6 order and starting this as all parts except for upgrade motor I can probably source locally(I am in oakland with 3dr offices in berkeley) and centruty helecopter for phantom parts in SJ..the frsky gear is a good bit cheaper than I thought and the only thing left is scoring a hero black for wholesale...y6 is NOT supposed to be delivered until nov 15 anyway
hzl
cool thats what I thought.. I wonder if twisting the powercabling could cancel some of the EM field affecting the compass as well as using donut toroids on the power feed wires into the APM?
wow that frsky module is small.. hmm were you able to stuff the 3dr telemetry module in as the frsky doesnt provide in that model receiver?
hzl
I used the FrSky V8R7-II receiver, as can be seen in Figures 3 and 4. It's very small and light, whereas you might have a problem fitting other receivers in such a cramped space.
My compassmot was not too bad, I think around 6%; I was careful to put the power wiring at the very bottom of the case, and zip-tie positive and negative power wires tightly together to reduce the enclosed area.
But yes, if I did it again I'd probably want to use the APM 2.6, and put the GPS outside the case.
and would the 3dr 2.6 autopilot with external compass be a better choice(?cased or decased thinking decased for absolute mininum loft weight.)
hzl
So I didnt see a ppm receiver on above parts list what rc receiver was used with this build if any?
would be arduphantom builders would like to know..
hxl
-
2
-
3
-
4
-
5
-
6
of 6 Next