Does anybody else mistrust RTH?

[JS_2016]

If that really happened without any user error or a critically low battery , I'd be sending mine in for repair. Only because In my experience the RTH on the Mavic DOES indeed work flawlessly.

Yes, no user error and no critical battery warning. It just tried to land right there.

Were you less than 65 feet away from the aircraft?

yes, I was about 40-50' from the aircraft.

 

[whiskeylover]

yes, I was about 40-50' from the aircraft.

Then the aircraft behavior was as expected. It WON'T climb to the RTH altitude, but just start landing wherever it is immediately.

Here, check out this video for detailed explanation.

Remember, on RTH -
1) Aircraft closer than 65 feet will start landing immediately
2) Aircraft more than 65 feet away will ascend (but not descend) to RTH altitude, and return to home point and land
3) Forward and bottom sensors work up until the aircraft starts to land.

 

[JS_2016]

Were you less than 65 feet away from the aircraft?

It works as designed. If you are between 16 and 65 feet in distance pressing RTH will cause an immediate descent and landing. More than 65 feet and it will return to home if precision landing is enabled and you launched according to the specs required to use it. If you're at more than 65 feet distance and didn't ascend high enough at launch for precision landing, when RTH is triggered it will be accurate to a few meters from home, as it searches for terrain that resembles the launch zone.

Thanks for the info, no I didn't see that in the manual! Good to know. I'll do some test flights with RTH. Thanks!!

 

[Rogue.Aircraft]

Thanks for the info, no I didn't see that in the manual! Good to know. I'll do some test flights with RTH. Thanks!!

I have reached this conclusion. Since the downward sensors are actually cameras, I try not to use them over large, single color, reflective surfaces. As it's nearly impossible to gain any type of distance or height perspective when the whole frame is a repetitive pattern with no identifying features. I don't know if you've ever had the chance to experience this, but take my word for it, 500 feet above the ocean, or 1500 feet above the ocean, if there's no land or identifying features in sight, they both look exactly the same. This is how your backyard looks to the Mavic when it's 10 feet off the ground over the grass. There's nothing but grass, it never gets any smaller, so it can never tell how close it is based on information gathered from the bottom cameras. I apply this train of thought to large grassy area's, large bodies of water, or huge empty parking lots. Although from what I have read over time, reflective surfaces such as water and grass seem to confuse the camera more than anything else. So in that situation it's now left to rely on barometric pressure and gps to determine height. Neither of which are accurate to the foot. Maybe 1 to 2 meters if you're lucky. Notice I say height instead of altitude, because it only recognizes its distance from the altitude of the ground that it launched from. It does not know where Sea level is, so It does not know if you are on top of a hill when you launch, or in a valley. This is the one flaw that I have noticed in the Mavic. It needs to have an altimeter. Without an altimeter it can never really know it's true distance from the ground, not without being close enough for the downward facing cameras and sonar to get an accurate reading. Which is something like 30 meters max I think. Basically precision landing requires that multiple things go exactly right. If you plan to launch your drone out of the grass in your backyard and expect it to come back and land exactly where it took off from, down to the inch, it's probably not going to happen. Not unless you run through a specific checklist when you take off, to make sure it can recognize an identifying feature with the bottom cameras to use for reference at launch. Then it can use that as a visual reference for landing. I notice a misconception around here where people seem to think that GPS positioning will put something within 6 inches to a foot of where it left laterally and vertically. That isn't the case, especially if you're flying on the minimum number of satellites needed.

 

[Kate]

Do you let RTH actually land Mavic though?
Even if i used RTH, I would only ever let it get within visual of the LZ and then take manual control
to land.
Only time i let the CPU land/takeoff my Mavic was in beginner mode, my first few days with it.

edit:
O and Rogue.Aircraft..

Paragraphs are our friends

 

[mavic6611]

Do you let RTH actually land Mavic though?
Even if i used RTH, I would only ever let it get within visual of the LZ and then take manual control
to land.
Only time i let the CPU land/takeoff my Mavic was in beginner mode, my first few days with it.

edit:
O and Rogue.Aircraft..

Paragraphs are our friends

You should do a precision take off, and the RTH it.. What it land with extreme accuracy. It's amazing to see and gave me so much more confidence of this amazing aircraft. Plus it really good to know it can be trusted if you evert need to use it. Saves you standing there chewing your nails off panicking whether it will work or not.

 

[Rogue.Aircraft]

Do you let RTH actually land Mavic though?
Even if i used RTH, I would only ever let it get within visual of the LZ and then take manual control
to land.
Only time i let the CPU land/takeoff my Mavic was in beginner mode, my first few days with it.

edit:
O and Rogue.Aircraft..

Paragraphs are our friends

Lol. This ain't no college thesis. But seriously I voice text and am kind of lazy about editing it after

And I don't ever launch or land from anything but by hand. Probably 90% of the time I launch it through the sunroof of my car and catch it by reaching up out of it when I bring it back.

 

[FlyingAround]

According to my Litchi film school RTH is dead accurate IF you do the following. Take off slow and increase altitude to about 10 feet . Hover a few seconds. The quad is mapping the area below it and it does it best from about 10 feet.
I have tested this dozens of times and my Mavic will RTH and land within 1 inch or less of where it took off. Even in moderate wind it is almost dead on. I hate the **** beep beep beep beep thing but RTH is friggin awesome (IMO)

 

[Storm chaser]

RTH is not flawless. My mp is 150 feet up a tree because RTH defaulted to zero when I pushed it. Had over 40 hrs on this bird. DJI has no idea what went wrong and no support.

 

[ric96]

RTH is not flawless. My mp is 150 feet up a tree because RTH defaulted to zero when I pushed it. Had over 40 hrs on this bird. DJI has no idea what went wrong and no support.

Sounds like operator error to me.

 

[BossBob]

Never used it though I always check the home point on the map and that the RC and AC are pointing in the correct direction, even when flying in woods.
It is amazing how much GPS recievers have improved. 10 years ago a garmin gps wouldn’t get a lock if there was anything above it. Now, iPad and drone both get good locks in conditions that would defeat that dedicated gps device.

 

[Storm chaser]

Sounds like operator error to me.

Thats funny how can you say operator error with the little bit of info I posted. You just proved my point that this is the first thing that people blame these situations on without facts.

 

[Tinmania]

Thats funny how can you say operator error with the little bit of info I posted. You just proved my point that this is the first thing that people blame these situations on without facts.

I think since you didn’t really include much information they went with the odds. I know that of all the claims of flyaways, and reports of return to home not working, I don’t think I have come across any that were not operator error to some degree.

But do post your logs, if you haven’t already in another thread.




Mike

 

[wytnyt]

edit:
O and Rogue.Aircraft..

Paragraphs are our friends

agreed,thats why i skipped the post myself

 

[Jacknet007]

Works every time.

 

[JDawg]

I used to use it and it was flawless. The very large percentage of people who have struggled with it never set it up right.

 

[Sprocket]

I used to use it and it was flawless. The very large percentage of people who have struggled with it never set it up right.

I use it every time. It is amazing to me how I can tell it to come home from a quarter mile away and have it land in its own paw prints. Half the fun of flying is having it land completely hands free.

 

[ac0j]

I love the RTH. I have the attention span of a spider monkey. Sometimes after I have seen whatever I flew to look at, I am done, Hit RTH and watch it come home. Never misses.
I didnt read every post in this thread but in case these were not mentioned,
The annoying beep can be removed with a third party software. Sorry, you have to find it cause thats all I know.
RTH works different in different situations. SO read the manual before you have a problem! If you never fly too far away from the takeoff point, the RTH behaves differenly than it does from 2000' feet away and 400' high.

I use RTH almost every time and only get involved when the bird is about 5 feet off the ground over the landing point to speed things up.

 

[MyMateDave]

I am new to flying and had the first forced RTH because of a loss of connection. I guess most people have the same feeling when this happens (panic) for the first time and everything is out of your hands.

Well thankfully for me i have OCD and double check all settings before a flight. I am happy to report, and also very relieved it came right on back as it should. I now have more faith in the technology to do its job when its needed.

I think it will take me some time to worry less when these situations arise but i am glad it worked.

Dan

 

[bushie]

I use it most times i fly with Go4. Many flights i preplan with DroneHarmony where the whole flight from takeoff to landing is automated. Enjoy seeing the MP completly doing its own thing, but have been a computer nerd since TRS80 days.