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Pumpkin drop event

GPS Help

#1
Hey guys. So after losing my tricopter from flying too far, I have vowed to never let that happen again. However, my knowledge with this sort of equipment is pretty limited. I've only messed with the KK2 and I don't like the lack of future functionality that board offers. So I ordered this stuff, in order to have a RTH function:

Multiwii and Megapirate AIO Flight Controller w/FTDI (ATmega 2560) V2.0
NEO-6M GPS Module
Multiwii FC I2C-GPS NAV Module

I definitely jumped the gun though, pretty much because the price seemed really good. Problem with this is I have no idea where this stuff connects or why I ordered 2 modules (aside from someone on hobbyking saying to order the NEO and NAV Modules). I believe the I2C thing connects to the board, and I'm guessing that the NEO goes into the transmitter (mine is a 9XR, using DragonLink). Do I have this correct? I just want to wrap my brain around it before it all arrives and I'm sitting there with a lump of cables and boards I have no idea what to do with. I'm in over my head, but I am determined to figure this stuff out. Seems the programming bit will be the most difficult. I have a USBasp. That's another question: do I need anything else? The NEO Module says you need a USB to FTDI adapter board...is that what the I2C Module is for? Sorry for all of my (probably ridiculous) questions. I just can't lose another $450 system from flying too far out...
 
#2
Alright, figured it out. The FC has the I2C thing built into it. Ran into a bigger question now, though. My understanding of how the GPS module works is fuzzy. The GPS is connected to the board, which then connects to the receiver. Now, how does the RTH function work (the whole reason I got the GPS module)? Does it use the same signal coming from your transmitter (I'll be using DragonLink) to guide itself back to you? It almost seems to good to be true, which worries me because I have a very limited budget. Thanks for any help or suggestions as to where to look! I can't find any clear-cut information on what equipment is needed for the RTH/GPS function to operate. I'm assuming I'm ok with the NEO module itself? Thanks again.
 

Tritium

Amateur Extra Class K5TWM
#3
If the system set up is correct the GPS will remember the starting Latitude and Longitude and upon loss of transmitter contact should return to those coordinates (in theory at least). Have you got your Ham Radio Call Sign yet?

Thurmond
 
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#4
That makes total sense! Geez, I feel silly even asking it now haha. Thank you.

I don't have the amateur radio license yet, but I plan to. Once I get accustomed to the new board and get gps working correctly, the next leap is into fpv. I usually fly in the middle of nowhere, so haven't given the license serious thought until all these UAV laws started coming out. Idaho is pretty conservative so I imagine they would crack down on that sort of activity.
 

FlyingMonkey

Stuck in Sunny FL
Staff member
Admin
#5
Jaya, a word of advice from someone who has been there... read as many pages of reviews, and set up guides as you can find. Likewise with videos that explain everything from plugging things in, to configuring the systems.

These boards (unless they've improved a lot since I tried my last Wii board) are not plug and play. They take a lot of tweaking to get right.

Done wrong it will flip, shoot off into the unknown, or drive itself into the ground for reasons you will never figure out.

When set up correctly they seem to be the "too good to be true" that you're looking for.

I never was able to get mine to that point.
 

Tritium

Amateur Extra Class K5TWM
#6
That makes total sense! Geez, I feel silly even asking it now haha. Thank you.

I don't have the amateur radio license yet, but I plan to. Once I get accustomed to the new board and get gps working correctly, the next leap is into fpv. I usually fly in the middle of nowhere, so haven't given the license serious thought until all these UAV laws started coming out. Idaho is pretty conservative so I imagine they would crack down on that sort of activity.
Yea, I am in the middle of nowhere also but the FCC has ears with every Ham Radio operator (if a ham intercepts transmission or interference and files a complaint then here comes the FCC) and some of the fines the FCC has handed down for no license is way more than I could afford so I took the safe route. The license is required for the long range transmitter and for certain FPV frequencies. I am using 1.2GHz for FPV and have yet to get a Dragon Link (currently using FrSky).

Flying Monkey is correct: setup for RTH is everything and difficult to obtain sometimes (I have APM 2 and have never tried to set it up but it is probably easier on APM than MultiWii or ArduPirate platforms). Still though I see reports of fly aways and unexpected crashes / strange behavior on the APM forum once in a while.

Thurmond
 
#7
Monkey: I've been reading up as much I could the last couple of days and I think I have a rough idea of what to expect. I'll admit though, I didn't even know what software to get to install the firmware until today when I PM'd lobstersmash (I believe that's his name). I was looking everywhere. The major problem was that everyone seems to be an expert already and getting into this as a complete noob, there's a major learning curve. Luckily, the board has been out a fair while now and there's almost 400 pages on rcgroups to go through.

Tritium: Well, initially I'll be using an Orange rx w/ my DX6i, since I lost my AR6200. I need to send DragonLink to Mike anyways, so he can update it. I've only hooked it up to the 9XR and got a green light, which made me happy as I've had it a couple years without messing with it because it was a huge pain to hook it to the DX6. I figured I'll be messing with with the new board and GPS long enough to get the Ham License. I plan on using 1.2 as well. May I ask what your setup it?
 

Tritium

Amateur Extra Class K5TWM
#8
RMRC "Cheap 1500mW Transmitter" 1258MHz and 1280MHz. Receiver is RMRC 900MHz-1.3GHz Audio/Video Receiver. I still need a low pass or notch filter to prevent harmonics on 2.4GHz flying frequency. I have been flying (and will again if the wind ever allows) with the standard FrSky Telemetry module.

Thurmond
 
#9
RMRC "Cheap 1500mW Transmitter" 1258MHz and 1280MHz. Receiver is RMRC 900MHz-1.3GHz Audio/Video Receiver. I still need a low pass or notch filter to prevent harmonics on 2.4GHz flying frequency. I have been flying (and will again if the wind ever allows) with the standard FrSky Telemetry module.

Thurmond
I may just copy you Thurmond, haha. Couple months out from doing FPV, though. The goal is to get out to 5 or so miles, with enough knowledge and time, that is. With the right antennas, is your system capable of that distance?
 

Tritium

Amateur Extra Class K5TWM
#10
Given perfect conditions and with the right antennas (IBCrazy's, helical or crosshair at receiver and Cloverleaf at transmitter) it should do 10 or more I believe (I really think 30 miles may be possible and am planning to test at 2 points about that far apart) but it is still untested at this distance by me. I have read of 10 miles with 500 to 800mW transmitter at this frequency.
I won't know till I have hard data which will only hint if it is possible since the distance pretesting will be on the ground with fixed stations at each end, not one moving in the air as actual conditions will be. I may just be dreaming but hey, radio experimentation is what hams do (even new ones).

My aircraft control system range is about 2 miles here in the middle of nowhere with the FrSky Module and Turnigy 9X running er9x.

I have been looking at this
http://store.rfdesign.com.au/rfd900-modem-bundle/
to use with my ArduFlyer 2.5 to let me use a Laptop computer and a joystick to fly past my regular FrSky range. Otherwise my craft could fly autonomously when out of RC transmitter range
using the APM Mission Planner to set waypoints in flight via the modem linked above.

Thurmond
 
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#11
I'll keep an eye out for your results, that's quite a goal. Wouldn't 30 miles on the ground be much more difficult than while you're airborne?

I need to look into this FrSky Module, as well. I've heard it mentioned quite a bit, but I have no idea what it is.

Shows what I know.