My point exactly. Why then do you 'have to keep visual LOS' at all costs as the poster I quoted suggested.
Lost mine today, RTH failed.
- Thread starter Androne
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Meta4
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Ordinary asphalt roads shouldn't cause a problem.
They are just made of compressed crushed rock + asphalt.
But be careful that you don't calibrate somewhere with buried steel pipes or power cables or structural steelwork.
There seems to be several posts where it's stated that more than one compass calibration is needed in order to achieve a successful calibration. A better way to look at this is that the failure rate is greater than 0. If multiple bad calibrations occurred then it's likely that a calibration subsequent to the successful calibration will also fail. A failure rate greater than 0 is cause for concern. It's an indication that something is wrong; either the location or the compass itself. A successful calibration after one or more failed calibrations is marginal at best.
Personally, if I had an unsuccessful calibration and thought it was location related I'd move to a new location. If a successful calibration is achieved then repeat calibrating several times to make sure that it's because of the new location. Then I'd take it back to the previous location to see if the bad calibration was caused by that location. If confirmed then back to the new location and 2 or 3 successful calibrations before flying.
Personally, if I had an unsuccessful calibration and thought it was location related I'd move to a new location. If a successful calibration is achieved then repeat calibrating several times to make sure that it's because of the new location. Then I'd take it back to the previous location to see if the bad calibration was caused by that location. If confirmed then back to the new location and 2 or 3 successful calibrations before flying.
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I can and I have terrible eyesight. Part of the experience that comes from flying RC for 25 years. Tiny dot getting smaller means going bye bye. Tiny dot getting larger means getting closer. Tiny dot going up mean well up. Tiny dot going down means well going down. Left and right should need not explanation.
I do suggest that everyone add some form of contrast improvement to their craft. The white is terrible for long distance location. Blends with the sky far to easy.
I am glad for the helpful info from the members of this group so, risking the expected spanking from Snerd for daring to show up in his hobby prior to achieving guru status, I'm going to continue to drill down on this.
If a faulty compass calibration is the accepted explanation I would assume that it went to a false RTH point and landed, right? Since the only obstruction was one very narrow tall building a block away, shouldn't the signal have reconnected once it cleared that building? It would be a huge coincidence that the craft randomly changed course to one that remained directly in that building's shadow. Or so it seems to me.
If a faulty compass calibration is the accepted explanation I would assume that it went to a false RTH point and landed, right? Since the only obstruction was one very narrow tall building a block away, shouldn't the signal have reconnected once it cleared that building? It would be a huge coincidence that the craft randomly changed course to one that remained directly in that building's shadow. Or so it seems to me.
Hi Wetdog
Just read this whole topic and ya some of the compass stuff can be confusing but..
That info of ascending to 20 meters IS correct.
What happens, which you can confirm in the simulator, if you set RTH height over 20 meters eg. 50meters and your flying below 20 meters and RTH is initiated by either a Smart RTH or you press RTH button the aircraft will rise to 20meters during which you have no stick control. It will then continue to 50 meters (or whatever you set RTH to) during which if you move the sticks it will stop ascending and head for home.You will have stick over ride so you can affect pitch and altitude but it centers on heading home. I you don't touch the sticks it will ascend to 50 meters(or what you set) and head straight home.
All just as richa's post showed
Not correct . The phantom only needs a gps signal to work properly . Check sensor mods before each flight . Based on those numbers it's easy to tell if you need a calibration. 1.5 million ft and not 1 single issue with any of my flights .
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No sir, just saying you are suppose to have a physical sight of your aircraft. Not what you can see on your Air but what what you can see.
I undestood what you said - hence my reply.
What I don't understand is "why?". Read my post again carefully and answer the questions in there.
If you believe you should always be able to see your quad the you really wasted a lot of money on your P3. A much better buy would have been a Solo or Blade with a half mile Wifi range.
True, but Smart RTH is based on the red/yellow/green battery line at the top of the Go app. Smart RTH initiates when the software determines you have just enough energy remaining in the battery(+ small reserve) to return to the home point. This is only available once during your flight. If cancelled, Smart RTH will not reactivate. The others are still available though.
There are 3 RTH modes. Smart RTH (battery energy), Failsafe RTH (loss of RC signal for 3 seconds) and RTH (user initiated). You can activate RTH as many times as you like from the RC or the tablet. I've used it 1/2 dozen times in one flight before.
SD
???? I never questioned anything about the RTH functions other than needing a gps signal.
Sorry Phantom, I wasn't questioning your info. I just quoted your post to preface the differences in all the RTH modes. A lot of users (lately) think they are all the same, and some believe RTH is just an emergency feature, which it can be but there's more to it than that.
No offense intended.
SD
It was probably coming down, it's really hard to tell sometimes but it definitely was moving down.
Cool no worries . I appreciate you clearing up the confusion with the different RTH functions .
ianwood
Taco Wrangler
The problem with an asphalt road or any other man made surface is you just don't know. Calibration may complete and look like it was successful even when there are localized magnetic fields that will skew the calibration. This is why calibrating in a place with the lowest likelihood of manmade objects or other sources of interference is best i.e. a big open field.
I'll admit this is a little paranoid but the compass is the Achilles heel of the Phantom and all compass based AHRS systems. It is the number one cause of calamities.
When I need to calibrate the compass, I go to the same place each time. Once calibrated and tested, I don't touch it until I have to go out of town.
RTH is a convenient feature of the Phantom. When returning from a long mission it is a convenience. If you prefer not to use it that's cool but please don't decide for everyone that they shouldn't take advantage of the feature!
I agree. I use it all the time, and you can have it going to Home Point and pan rear or sideways if you want for some different video perspective.
The problem with the suggestions to not recalibrate the compass is, when the app gives a compass error your choices are to recalibrate or not fly because it won't allow the motors to start until a successful recalibration is complete. Unfortunately this happened so often for me I considered it routine. It now seems to me that the app could be better designed by providing a "magnetic interference" warning instead of simply prompting to recalibrate. IMHO
I'd be concerned about needing to calibrate frequently. I would try to find the cause.
Near some unseen metal or RFI (large motor behind a wall etc.)?
Problem with the calibration procedure?
Faulty compass in the Phantom?
Software/Firmware issue?
Faulty compass calibration makes the P3 swirl around and doesn't seem to know what to do next.Scary.
I calibrate in an open field then not do it again ( if readings are near 1500) and hover is stable.
I've moved 200 miles and it's still good, yet get near a bridge and the compass goes bad readings but the calibration isn't bad. I'm too close to source of interference. Move away from it and compass is good again with no calibration. Hope that helps someone.
