My First Multirotor, Comments Requested

[Autonym]

Hey folks,

I've started!

Many boxes filled with tiny electronics from exotic and far-flung places like Shenzhen, Texas, and California have found their way to my home. I've been busy with soldering iron and electrical tape assembling these items into something I hope someday will fly. I have made a chronology of my experiences here: Tree Dodger.

NOTE: I'm a complete newbie at this, so please, please, comment on my set-up, my selected components, posts from my blog, everything - I really don't know what I'm doing, and I'm sorta smashing things together until something works.

I intend on doing this in phases, to get my footing, so to speak, and also give my pocketbook a break. For things I provide a URL for, I've already purchased. For things I'm still needing to buy, I have a (TODO) after them. Suggestions for TODO items is greatly appreciated:

Phase 1 - Basic Frame, Visual Flight:
Genuine DJI Flame Wheel F450 ARF (2212/950 kv motors, 10x4.5 props, 30A ESC's) (Assembled)
Crius AOIP V2 Flight Control Board with ATMega 2560-16AU (Assembled)
Crius CO-16 OLED Display (Functional)
Crius AIOPIO Board (Assembled)
RCTimer Voltage & Current Sensor 90A (Installed, not Integrated)
RC Hobby 7A U-BEC UBEC (Assembled)
RCTimer AVDome Protection AntiVibration Dome (Partially Assembled, Pending Completion)
FlySky TH9X 9 Channel Radio with 8-Channel Receiver (Functional)
4000 mAh 30C 3S LiPo Batteries (Need Power Lead Adapter)

Phase 2 - Add First Person View Flight + GPS Autopilot + Telemetry:
Crius CN-06 GPS V2 (Need To Reflash to Correct Baudrate)
RCTimer MAVLink-OSD V1.0 (Pending)
433Mhz Radio Telemetry Kit (Pending)
Decent Low-Light Camera (TODO)
Decent Video Goggles (TODO)
Video Downlink (TODO)
3000 mAh 30C 3S LiPo Batteries (TODO)

Phase 3 - Add Gimbal-Stablized Camera + Video Switcher + Long Range RX/TX:
Video Switcher (TODO)
Gimbal (TODO)
Visible-Light Camera - GoPRO? (TODO)
Thermal Camera - FLIR Quark? (TODO)
433 MHz Transceiver replacement - Dragon Link? (TODO)

So I'm working on Phase 1, getting the frame together and parts mounted. There's a bit of blurring, as I already have some of the Phase 2 parts, and I'm working to get them integrated as well (GPS and 433 Telemetry Link for now).

I've decided to go with MultiWii over the other flight control software frankly because it seems leaner, cleaner, and less complicated. I like that.

I've already worked through the Crius OLED bug where you have to add a 100 ohm resistor to +5v to delay its initialization ever-so-slightly to get it to work right. I have some questions on how I want this to work, however, that I'll mention in a post later.

As far as I can tell, the GPS unit is a UART/TTL/FTDI and not I2C, so I'm trying to attach it to one of the 4 serial ports that the ATMega board includes, but I think its baud is set to 9600 instead of 115200, so I'm waiting on a USB/FTDI cable to reprogram it using the uCenter tool from uBlox. Has anyone used this GPS, and am I doing this correctly?

Another thing I tried playing with a little bit, and can't figure out is the 433 MHz serial telemetry link. I want it to just connect a serial console port through the radio, so I can run things like MultiWiiConf or MultiWiiWinGUI while it's airborne (without using a REALLY LONG USB cord). Yet I don't see any settings anywhere to configure such a link, or specify my secondary data serial port. I found the RCSERIAL definition, but that replaces my traditional R/C controller, which I don't want. Has anyone got the 433 MHz telemetry working?

I've also posted on this separately, but I'm also looking at integrating some AdaFruit NeoPixel lights into the frame itself to assist with visual orientation and for cool-factor. I've a 60 LED/1M strand coming in the mail (along with my FTDI/USB interface to fix my GPS) that I'll be prototyping with my Arduino Leonardo board until I can figure out how to get compiled into MultiWii without compromising flight stability.

Thanks for any help with what I've got going on here, it's greatly appreciated!

[linuxslate]

I don't see any settings anywhere to configure such a link, or specify my secondary data serial port.

I'm not an authority on this, but AFAIK, you do not have to.

MultiWii will answer MultiWii Serial Protocol communications on any serial port that is not configured for something else.

(My answer comes from the fact that it is the same as my OSD setup - I just connected it to an available serial port and it works.)

So MultiWiiEZGUI will send a request through the 433MHz system and MultiWii will answer.

You will need to flash the Mavlink Board with KVTeamOSD. MultiWii does not speak Mavlink natively (although there are projects to do this).


When I built mine, I went with a bluetooth link straight off instead of the OLED panel. With MultiWiiEZ-GUI, any android phone is a better display panel, and the BT adapter is cheaper than the OLED, lighter, too.
I'm not saying to use the BT link instead of your phase 2 TLM link, just suggesting it as an option in phase 1.
You can use it just for on-the-ground configuration (like the OLED), but you may be surprised in the range you get should you use it while flying, depending on the phone.
I just did not see the point of flying a screen I cannot see/touch while flying.
I was also making a big effort to keep my phase 1 cost down.

[Autonym]

Thanks for these great comments, Linuxslate!

I'll have to fiddle with the 433 MHz HF Link and see what's up with that. The BT option was tempting, but I do iPhone instead of Android, and I was worried about the range - I'm in a heavily wooded area, and eventually wanted some sort of laptop-setup for ground station telemetry, etc.

Yeah, the OLED was totally an impulse buy. It's all of 5 grams, so I can swing it for now. I may remove it, but the cool factor was just to much to pass up.

Also, nice tip on the KVTeamOSD bit - I'll definitely follow-up on that once I get the video transmitter purchased.

Anyone else have some helpful advice?

[Autonym]

WOOOOOOOT!

Thanks again Linuxslate, for encouraging me to "just try it". Turns out, the 433 MHz link was just set to 57.6 kbaud instead of 115.2 kbaud. Once I used *ahem* Mission Planner's 3DR configuration feature to reset the baud rate, I was good to go!