I just got a last minute request to record a movie production inside an old iron hanger with a high ceiling. I know that I need to have GPS off. Any other tips? I fly through a small 30 foot tunnel yesterday for a country club and I really found out what a wind vortex these things produce. I just flew it manually straight through. I think with a big wide open hanger it should be fine?
How does that work if I'm not using GPS? Does MK electronics still use the compass with GPS off? I guess I could do a quick up and down there and check the log file to see if the compass is working? Any more feedback?
On startup if checks for magnetic deviation. If it exceeds the value your get a pretty persistent error message and noise from the lady. You might have encountered this trying to take off of a concrete pad or parking lot. The rebar in the concrete affects the value and no motor start. http://www.mikrokopter.de/ucwiki/en/MagnetError?highlight=%28magnetic%29%7C%28deviation%29 You mention not using the GPS but my read of this is that you would need to disconnect it and perhaps even the NAVI board to get the compass out of the equipment path. Andy?
You can pretty much ignore the compass errors (which you'll get), or you could disconnect the Navi board altogether. You should also be super careful of being anywhere close to the roof inside. You'll find that the closer you get to the roof, the more likely you'll experience the opposite of ground effect, meaning that the copter will be drawn towards the roof. But if this is a Truly Large Space, I'm sure you'll be fine. After all, what could possibly go wrong?
So if I have the nav and GPS cables unplugged it still works fine in manual Mode? Steve as I read this I'm like oh my I can't believe what I just did then!!! Check out this video! This is part of 3 days worth of footage I did for a country club that will be used for a commercial we are doing.
Oh, I thought it was the 5D or GH3. You can "lock" the 760's exposure, which is more or less the same thing, and in this situation would accomplish the same effect.
Would disconnect the Navi-Ctrl and GPS boards entirely. That also removes the compass (which is on the Navi-Ctrl board). Then you are fully manual -- with the exception that you can still use Altitude Hold. What I'm not sure is whether you also need to check the "Ignore compass error at startup" in MK Tool. With the 860, you can either preset the aperture, or you can preset the shutter, but I don't think you can do both simultaneously. Check page 42 and following for the manual settings. Check pages 39 and 40 of the CX760 manual for Night Shot and Low Light shooting. Andy.
I just did an indoor shoot in a cathedral. I had never bothered with the flashing lights on low battery because I had fraulein Graupner to warn me. Indoors was way too noisy to hear her and I fried a battery. Oops! Steve is correct; that ceiling effect is way worse than ground effect. There are also weird drafts and vortexes from the walls too. Nothing like a good challenge. Have fun.
Yikes! Now you have me worried. What could have fried with low voltage? I had a lower than desired cell voltage but it landed safely.
Guys Thanks for the feedback. I have no problem unplugging the connectors for the GPS and NAV, the only question is why do you need to do this if you are not going to engage PH? Just trying to understand the theory and understand how the circuits work. Doesn't PH engage the GPS and if PH is off doesn't that mean the GPS and NAV are bypassed? Or are you saying that MK uses the GPS and NAV electronics even when you are flying in normal manual mode? Andy you mentioned "fully manual", is this different than flying in manual mode but with the GPS and NAV boards hooked up?
Let me see if I can construct a couple of plausible scenarios, Dave -- and let me say up-front that these are "imaginary horribles" -- they may not happen: 1. You're indoors, but you have GPS/Navi-Ctrll connected up. 2. You go to start the motors, then start, but they will not throttle up. What's causing that? Well, in MK Tool, you have set Enable GPS, and you have Min. Sat. set to 6. But you're not getting any satellites (or maybe one or two). Or perhaps you forgot to do a compass caiibration, the compass is going bonkers (because of all the distortion because you're indoors) and you have the "ignore magnet error at startup" unchecked. Or this scenario: 1. You're indoors, but you have the GPS/Navi-Ctrl connected up (but you've set the Min. Sat. to 0 and you've checked "ignore magnet error at startup.) 2. As luck would have it, you've got a good enough GPS signal through the windows to get a 3D fix on where home is when you did motor start. 3. But, because you're indoors you're not going to use PH because you know that you don't have any (or a reliable) GPS signal and indeed the GPS signal disappears shortly after take off when you move away from the windows. 4. Also, because you're indoors there is a huge amount of multi-pathing (internal reflections) of the flight control 2.4 Ghz signal -- or there are WiFi nodes all shouting on the same frequency band as your Graupner. (This is a hypothetical: I must admit I lean towards the Wifi hypothesis more than the multi-pathing hypothesis.) 5. Either way, the Copter loses contact with the Transmitter. What happens then? Will it attempt to go into PH for 5 seconds, then go to Come Home altitude, and then execute an Emergency Come Home? I'd like to think that the fact that it had a home fix, but subsequently lost GPS data, the copter would not do anything daft. Alternative: Wouldn't it be safer to disconnect the GPS and Navi boards? Actually, you just need to undo the two ribbon cables from the FC to the NC and you're done. Then the firmware on the FC realizes that there is no NC, compass, or GPS and simply shuts off that part of the logic that deals with them. What will it do then if it loses contact with the transmitter? Descend in place at emergency throttle (make sure you have the "use vario control for failsafe altitude" checked so that the Emergency Gas is a percentage and have it be some value like 90%). So, hence my suggestion. Deliberately turn off the GPS/Navi to avoid any possible unintended and unexpected consequences. I may well be wrong about this, but if I'm not, it could be an expensive way to find out. Andy.
All I meant was that I hoped the battery didn't actually fail in flight. If by frying a battery you mean that it landed OK but it's now a brick, then whew...
HI Andy Thank you so much for clarifying. It makes complete sense. I wasn't doubting what you were saying I just wanted to make sure that I understand what you meant by "complete manual" flying as I wasn't sure if the compass some how was still influencing the direction of the copter even when in PH. I can fly the copter pretty good in manual mode or I wouldn't have gone through the tunnel above but it just put another thing in my head saying "will the copter be more difficult to fly or respond differently without the GPS and NAV". I just didn't want that in my head shooting my first scene indoors in front of a lot of people. I was pretty good in making the copter going through the tunnel (man there was some strong wind vortex being produced while flying in that tunnel) and I know I need to be careful of not getting to close to the roof or sides now. One last question for you if you don't mind. Should enable GPS be unchecked as well?
Dave, I just went for it, all circuits connected. But after reading what Andy said; Yikes again. I think Andy is overly cautious but if I had read his words before I did the indoor flight I would heed his advice. It makes sense; slim chance of these scenarios playing out but why take the risk when the solution is as simple as disconnecting a few ribbon cables.