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RTH Accuracy Caution

AdventureCity

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Rosenberg TX
Well, it happened. This morning I started my flight from my driveway. It always tells me that it has updated the Home Point, and it did so this time. I have a very large area that I can fly in and I found that at about a mile away, the video I was receiving was getting temperamental. I knew that I was at risk of loosing my connection, so I tried increasing height, which worked. I started the return flight when my screen went black. Oops, time to move around to see if I could regain the signal. While I was trying that, the video image started again and I could see that it was doing an automatic RTH. This was satisfying. When it was close to the house I saw it high overhead at the 150 feet that I programmed. It started it's descent, but it was very difficult for me to determine if it was over the driveway. Suddenly I realized that it might not be over my driveway, instead it may be too close to the house. I quickly tried to cancel RTH, but in looking back and forth between the drone and controller repeatedly, in my panic I clicked on "No" for Cancel. It descended until one leg was in the rain gutter. It was making a terrible racket. I then tried to fly "up", but it would not. After what seemed like forever, it finally stopped all motors and tumbled to the ground. My guess is that when its descent stopped, it thought it was on the ground.

I have heard suggestions that upon takeoff the drone should be hovered for a while high above the starting point (30 feet?) for accurate RTH, but I don't know if this is a myth or a requirement.

Moral to the story, my story, is to always cancel RTH when it is close to the landing site, if possible. Lesson learned. Fortunately the only damage included: white paint and nicks on the propellers, gimbal plate was 'out of place' and could be moved back into position, and the aftermarket lens hood shade popped off.
 
Sorry to hear about your damage, but happy it was not worse. Couple comments. Yes the the 30 foot hover upon takeoff is something that is needed in order to get a precision landing - it has been tested and does not work as well if not done or done at lower heights. Also I try to avoid launching from any point where there are trees or buildings nearby that could negatively affect the landing. You have to consider the possibility of not being able to regain the signal and if that happens you would not be able to cancel the RTH or guide it back in - depending solely on the RTH accuracy.
 
Well, it happened. This morning I started my flight from my driveway. It always tells me that it has updated the Home Point, and it did so this time. I have a very large area that I can fly in and I found that at about a mile away, the video I was receiving was getting temperamental. I knew that I was at risk of loosing my connection, so I tried increasing height, which worked. I started the return flight when my screen went black. Oops, time to move around to see if I could regain the signal. While I was trying that, the video image started again and I could see that it was doing an automatic RTH. This was satisfying. When it was close to the house I saw it high overhead at the 150 feet that I programmed. It started it's descent, but it was very difficult for me to determine if it was over the driveway. Suddenly I realized that it might not be over my driveway, instead it may be too close to the house. I quickly tried to cancel RTH, but in looking back and forth between the drone and controller repeatedly, in my panic I clicked on "No" for Cancel. It descended until one leg was in the rain gutter. It was making a terrible racket. I then tried to fly "up", but it would not. After what seemed like forever, it finally stopped all motors and tumbled to the ground. My guess is that when its descent stopped, it thought it was on the ground.

I have heard suggestions that upon takeoff the drone should be hovered for a while high above the starting point (30 feet?) for accurate RTH, but I don't know if this is a myth or a requirement.

Moral to the story, my story, is to always cancel RTH when it is close to the landing site, if possible. Lesson learned. Fortunately the only damage included: white paint and nicks on the propellers, gimbal plate was 'out of place' and could be moved back into position, and the aftermarket lens hood shade popped off.
Sorry to hear of your mishap I am glad it was not worse.
Regards,
-d.
 
Sorry to hear of your mishap I am glad it was not worse.
Regards,
-d.
Actually there was more to the damage: Gimbal recalibration, Gimbal roll adjustment, more white paint than I suggested, grass and dirt. However I am much more concerned when things are broken, so I came away from this feeling fairly good. I have told my very interested friends and observers that I intend to wear this out so I can justify the next great drone toy, thus I have flown at least once daily since I got it. Lots of fly time means things happen sooner or later. I am having a great time trying to meet my objective.
 
Try to practice switching from GPS to sport (or vice versa) without looking at the switch. It's is a fail-safe way to kill whatever automated routine the MP may be executing - including RTH and auto-landing. It works even when the screen is B&W and you still have RC comms.

It's a little late now, sorry...
 
Try to practice switching from GPS to sport (or vice versa) without looking at the switch ...

That is an excellent tip. I have my software (Multiple Flight Modes) set to recognize a change to the switch. Would you know if that tip is still true if if MFM is turned off?
 
That is an excellent tip. I have my software (Multiple Flight Modes) set to recognize a change to the switch. Would you know if that tip is still true if if MFM is turned off?

I've never flown with MFM turned off, so I can't say that it would(nt) recognize the switch. However, from accounts of others, that switch is at the very root level and takes precedence over even the most basic autonomous (firmware-driven) routines. Without testing it myself, i would say with 90% confidence that it WOULD stop the RTH/auto-land in the single-mode configuration.

ETA: I just made a quick test flight with single mode enabled. I initiated RTH, and once it was on its way back to me, I flipped up to the switch from GPS to sport, and immediately the RTH stopped. I did get the pop-up telling me I can't fly in sport mode until I enable MFM - which is normal. So, I amend my previous comment... I'm 100% certain that the sport/gps switch will cancel an RTH, regardless of the mode.
 
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I tested this and found that you are correct. I hovered for maybe 10 seconds. Would you know the minimum?

Ive read the MP has a light sequence or makes a sound when the RTH "picture" is taken. Any idea what that sequence is?
 
I tested this and found that you are correct. I hovered for maybe 10 seconds. Would you know the minimum?

Sorry I have not found anything that spells out the minimum hovering time for a solid image. All I have heard is it needs to be for a few seconds. I think it also helps to take off either from a landing pad that has nice contrasting markings or if that is not available anything that makes a certain spot look different than areas next to it. My RTH's have been really precise when using the landing pad.
 
Ever wonder why those landing pads have patterns on them? Because the downward facing cameras record them and come back to them.
If you want a precision landing, select the "precisely record takeoff position" option before you slide to take off, it will elevate to 30 meters and stop, once it stops it is done and the position is recorded. It has to go up to 30 feet to take a larger picture of the landing zone to compare to upon return.
 
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I tested this and found that you are correct. I hovered for maybe 10 seconds. Would you know the minimum?

I count to four once it's 30 feet up. So that saves you 6 seconds. Maybe more, but 4 works for me even if it's a little breezy up there.
 
I thought there was some sort of flashing LED sequence once the Precision RTH process was finished...

I haven't had the chance to try it but it seems like a good feature to have.
 
Sorry I have not found anything that spells out the minimum hovering time for a solid image. All I have heard is it needs to be for a few seconds. I think it also helps to take off either from a landing pad that has nice contrasting markings or if that is not available anything that makes a certain spot look different than areas next to it. My RTH's have been really precise when using the landing pad.

Using the landing pad makes a huge difference for me. I guess the driveway looks pretty much the same end to end so when I'm not using the landing pad, my MP seldom lands exactly where it took off from.
 
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There have been several times that I have used the auto take off function with the check box ticked to record the take off area in the hover.
My RC,when connected to my iPhone, makes a shutter sound indicating that the area has been recorded for RTH.
 
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