Wednesday, September 9, 2015

Super Nova - Modding for flight

Never thought I would have two of these quads. Like I said, one is just for parts, but I figure ... why not have two brushless quads to mod differently and fly while they are both complete and working. It needs a model name, if for nothing else to differentiate between them in my Radio and also as I post about mods and flights here on the blog. I think I will call this one "Super Nova".

Steps here are not listed in order of importance, but rather in the order of completion. I will just edit this post until finished. Some sub-parts might link to other posts.

I suppose it starts here.

Removed foam-taped Flight-Controller and GPS-Module from Power-Board (PDB).

Added nylon washers to raise PDB about 2mm. Also, removed black foam-tape from bottom of battery compartment. This will help my Turnigy 2700 Lipos to insert and remove easier ( now that they have been exercised and puffed-up a bit) and also give a tad more room for other battery makes. Can't go too high because of other things planned. My two Turnigy lipos fit much better now.

Mounted FC with Zeal so accelerometer is near middle of quad. Cut some holes to route cables through middle (never cared for running them out the back anyway). Since PCB is not actually screwed down, installed single-sided foam tape to prevent any vibration inside case.

This is the bottom of the APM 2.52_v5.0 HobbyKing/Cheerson FC. Connected properly wired custom cable for UART (915mhz Telemetry radio). As posted elsewhere on this blog, Cheerson wired this UART-Socket exactly backwards or reversed. If your radios came with a pre-made cable, most pins will have to be carefully backed-out and moved. Red is +5v power and Black is Ground. As you can see, I did that at the FC side. I had the pin-out, but still verified VCC with a volt-meter at FC first anyway. This is ONLY for the v5.0 version of this FC. I think best to now keep this modified cable mated to this FC.

Installed the Power-Module (details) in ADC port also (black marked on socket is Ground). You can just use XT-60 connectors if you want, but I eventually found them too cumbersome.

I2C port is the existing compass cable. The socket came bent like that, but it ohms-out and solder looks ok so I'm not messing with it.

Connected FrSky X8R with FC with SBus-to-CPPM Converter.

Going to try GPS-Module foam-taped to top of FC. This should basically locate the GPS-Module in "the dome". The FC and GPS-Module are now a unit, and should still be isolated from copter vibrations with Zeal (no part of that unit is touching body).
Installed 3DR 915mhz on bottom-rear of Super-Nova.

RC Radio Setup and Config:

Using OpenTX-Companion, copied Model#1:"Nova" to Model#2:"Super Nova" and uploaded to Taranis. Radio is now programmed for new model (that was easy).

Flight-Controller (FC) Software Setup and Config in Mission-Planner:
  • Connect USB cable from laptop to bottom on Super-Nova
  • Start Mission-Planner and click connect to test port and Connect ability.
    • Use Auto at first if you don't know com-port and baud rate
    • Click Disconnect but leave cable attached
  • Upload and Verify Custom firmware file v3.1.5 (from VinnieRC) aka v3.1.5c
  • Click Connect
  • Reset (Parameters) to Defaults for v3.1.5 and Reboot
  • Save initial v3.1.5 params to file
  • Click Disconnect in MP
So, this FC originally started on v3.1.2 (stock). No strange beeping now or since I started setup, but the next time I powered-up the Super-Nova, ESCs were beeping constantly. Seems to indicate that ESCs aren't getting a signal because FC can detect that radio is not calibrated yet (getting that message in MP-HUD). Looks like the constant ESC beeping only happens with a combination of ArduCopter v3.1.5 (or higher), ESC revision v1.6 (or higher), and an un-calibrated RC radio.
  • Connected other 3DR 915mhz Radio to laptop and click Connect to Super-Nova by radio
    • The FC was not "locked up" and there was no problems connecting to it.
    • While I started using my 3DR-Radio for the remaining setup steps, you could also choose to use a wired USB cable.
  • In MP, calibrated Radio, write params, click Disconnect and power-cycle (reboot) FC.
    • Since the radio is already programmed, in addition to the sticks, step thru all the pre-programmed Flight-Modes on the switches. All channels should move (except CH6 which is not assigned to anything on Taranis).
    • If ESCs were beeping they should stop now.
  • Set Frame Type to X-Y6A
  • Click Connect and calibrate the rest of the "Mandatory Hardware" devices. Accelerometer was usual procedure (keep still and perpendiclar). Before starting Compass, I went outside to get basic GPS-Fix for Auto-Dec. Final offsets were -125, 8, -33.
At this point, I'm still running only the ArduCopter v3.1.5 Default Parameters and tuning PIDs.
Some notable Default params are:


Calibrated ESCs (especially since this is a PnF model).

Set my Flight Modes in MP interface (and write/save):
1. Stabilize
2. Loiter
3. Alt-Hold
4. Drift
5. Land
6. Auto
... and in Extended Tuning, CH7=SuperSimple and CH8=RTL
(which I have on dedicated Taranis buttons)

Changed these non-Default parameters:



Tested Fail-Safe with no props installed (passed).

Completed SuperNova assembly.

Armed and carefully did low-throttle "hold by landing gear" test. Also, verify flight modes (passed).

Ready for maiden flight.

If it survives, I'll then work on adding a camera and/or gimbal.

EDIT: Results of maiden flight are here. It flies great.

No comments:

Post a Comment

The stupid spammers have now forced me to approve each Comment before it appears (but I am usually pretty quick about it).