Slow forward speed

[Butterfingers]

Received my new Mavic Pro last week and took it for a few test flights - loved it. All working well, RTH, flight controls, gimbal, camera, etc.

Whilst flying it on Saturday in the garden, a strong wind gust blew it into a wall whilst it was at about 1m above ground. Drone flipped over onto its back spun a few times until I managed to get to it and flipped it over and stopped the motors. Props a bit scratched and a scratch on the battery. Otherwise looked okay. Took off again and all great with one exception - forward speed very slow and maxs out at about 2m/s. Side to side tilt and speed and backward tilt and speed all normal, but forward tilt nearly negligible and therefore speed compromised. I've tried re-calibrating the Compass and IMUs - all good - but is there anything else that I can do?

Would greatly appreciate any advice!

 

[Mavicsailor]

Received my new Mavic Pro last week and took it for a few test flights - loved it. All working well, RTH, flight controls, gimbal, camera, etc.

Whilst flying it on Saturday in the garden, a strong wind gust blew it into a wall whilst it was at about 1m above ground. Drone flipped over onto its back spun a few times until I managed to get to it and flipped it over and stopped the motors. Props a bit scratched and a scratch on the battery. Otherwise looked okay. Took off again and all great with one exception - forward speed very slow and maxs out at about 2m/s. Side to side tilt and speed and backward tilt and speed all normal, but forward tilt nearly negligible and therefore speed compromised. I've tried re-calibrating the Compass and IMUs - all good - but is there anything else that I can do?

Would greatly appreciate any advice!

Are you sure the obstacle avoidance isn't slowing it down? Maybe try a wide open area or turn off OA and be careful.
You could also try sport mode in a wide open area. (Very responsive)By default OA is off in this mode.

 

[Andrew F]

You should replace the props and see how it flies. Sounds to me like something wrong with them. Also, when you remove them, make sure none of the tabs broke off and are stuck inside the motor mounts. I would also turn off the forward vision (be careful) and see if it flies normally. It's possible your crashed messed up one of the forward facing cameras. Finally, make a very close inspection of the arms and that they haven't been damaged. Pretty odd behavior. I'll be shocked if it flies normally in sport mode. It might be faster, but I doubt it would be as fast as it should be.

 

[Butterfingers]

Thanks for the advice - really appreciate it. I wonder if you've hit the nail on the head? OA is working normally, Neutral one of the cameras did get a little ding on the cover. I've flown it in a wide open space - no difference (still slow). Put it in sport mode and it took off. Not enough space to test it's top speed, but that's my next test. I'll also try turning off OA and see if it makes a difference. (By the way - I did change the props - no effect.)

I'll let you know how I go and thanks again for the advice. Nice to know that there are people out there willing to give of their time to newbies like me!

 

[Butterfingers]

You nailed it git is the OA. Turned OA off and it flew forward at normal speed. Now I have to figure out why. The front left camera has some dings in the housing cover - I wonder if the camera is damaged or the connection to the camera is loose? What would happen if one camera stops working? Would this also explain why RTH has stopped working? Press RTH and Mavic orients towards me, flies to within about 20m of landing point, then starts to climb to Max altitude (120m) when I cancel and bring it home manually. Will RTH work with OA turned off?

 

[Mavicsailor]

You nailed it git is the OA. Turned OA off and it flew forward at normal speed. Now I have to figure out why. The front left camera has some dings in the housing cover - I wonder if the camera is damaged or the connection to the camera is loose? What would happen if one camera stops working? Would this also explain why RTH has stopped working? Press RTH and Mavic orients towards me, flies to within about 20m of landing point, then starts to climb to Max altitude (120m) when I cancel and bring it home manually. Will RTH work with OA turned off?

Yes, RTH will work with OA off.

 

[Butterfingers]

Thanks - I'll do some more extensive testing (probably over the weekend) and let you know the outcome.

 

[Butterfingers]

Just done some static testing. Placed the Mavic on a bench, fired it up and connected it to the controller and phone. Turned on OA and tested the OA by checking the radar image. Both cameras are reporting obstacles within their fields of view as you'd expect. Green - Orange - Red as an object (me) approaches the cameras. Checked the left camera housing that was dinged in the crash and it appears to be slightly distorted (oval-shaped). Both cameras also seem to have distinctive marks (scratches) on the lenses - no idea how they could have happened as the lenses are quite well protected by the lens shrouds of the camera housing. (Photos attached.) I'll continue with my flight testing when I get a chance and update this thread.

 

[Dr. Dough]

The same thing happen to me last night. I accidently crashed into my house. This morning trying to fly it flew very slow forward. Ok at left, right, and backwards. In sports mode it rips.

 

[Butterfingers]

Try turning off Obstacle Avoidance (OA) and see if that "solves" the problem. It did for me, but I'm not sure that I'll be happy flying without OA enabled. Also check Return To Home - you may find that your Mavic just climbs as it "thinks" there's an obstacle in front of it that it needs to fly over. I'll keep this thread updated with what I find.

 

[erkme73]

If the slow down is consistent with OA being on even if there is nothing ahead of it, I'd try the VPS calibration process. Perhaps the lens distortion can be calibrated away? Sure beats sending it in if you can avoid it.

 

[Butterfingers]

Thanks @erkme73 - I did a re-calibration at the weekend after the crash and it seemed to make no difference, but I'm going to try again as I'm not sure that the calibration worked as it should. I'll watch a youtube video first to make sure that I'm doing it right.

 

[Andrew F]

I'm afraid one or both of the cameras are damaged and are reporting an obstacle that isn't there. It explains your RTH problem as it thinks a VERY tall tree is in its path (sorry I shouldn't joke.) Go to a very open area and see if the radar heat map shows something there. Bet it does. I'd personally plan on returning it for repairs at some point. Not an emergency if you just keep OA turned off. No worse than my Phantom 2. Good luck!

 

[Butterfingers]

Thanks Andrew - I will try that. Frustrating as I'd prefer to fly with OA on, but I don't really want to go through the pain of trying to return the drone from Australia as support here seems to be somewhat slow and limited!

 

[Andrew F]

Thanks Andrew - I will try that. Frustrating as I'd prefer to fly with OA on, but I don't really want to go through the pain of trying to return the drone from Australia as support here seems to be somewhat slow and limited!

Oh sorry, mate! Didn't know you were down under. Maybe they can send you a replacement and will refund your deposit when they get the damaged one so you never go without one. I've done that before with other similar products.

 

[Butterfingers]

Now that's an interesting idea, but before going down that route - my update...

I recalibrated the forward and downward vision sensors, compass and IMUs this afternoon. Whilst looking at the photo of the front left vision camera, I noticed that the top cover of the drone was slightly separated from the body, so pressed down on it and it moved a fraction and "clicked" into place. I'd watched a Mavic tear-down video yesterday afternoon and the guy in the video commented something about the pressure from the top covers holding the connectors for the cameras (and antennae?) in place. Interesting. So, I waited for the rain to ease off this afternoon at home and took the Mavic out for a test flight. Take off to hover and OA radar sensors reporting obstacles in front about 4m away - the fence. Took the Mavic up to 3m so it was looking over the fence and no obstructions for 10m - radar all green. Full stick forward and my demented dragonfly tipped over and took off at what looked like normal speed. Hallelujah! I couldn't take it for a full run - not enough space, but I'll put it through its paces tomorrow in the work car park and test it, including RTH. Keeping fingers crossed that she might be good...

 

[Andrew F]

Awesomeness! Solving it yourself is 10x better than getting it repaired. Good job!!!

 

[Dr. Dough]

Now that's an interesting idea, but before going down that route - my update...

I recalibrated the forward and downward vision sensors, compass and IMUs this afternoon. Whilst looking at the photo of the front left vision camera, I noticed that the top cover of the drone was slightly separated from the body, so pressed down on it and it moved a fraction and "clicked" into place. I'd watched a Mavic tear-down video yesterday afternoon and the guy in the video commented something about the pressure from the top covers holding the connectors for the cameras (and antennae?) in place. Interesting. So, I waited for the rain to ease off this afternoon at home and took the Mavic out for a test flight. Take off to hover and OA radar sensors reporting obstacles in front about 4m away - the fence. Took the Mavic up to 3m so it was looking over the fence and no obstructions for 10m - radar all green. Full stick forward and my demented dragonfly tipped over and took off at what looked like normal speed. Hallelujah! I couldn't take it for a full run - not enough space, but I'll put it through its paces tomorrow in the work car park and test it, including RTH. Keeping fingers crossed that she might be good...

I had been trying to sync up with DJI Assisant 2 for a while. After doing a compass calibration it had improved flight but still was flying slow in forward. Taking off OA did return to normal flight. After I finally successfully doing a Vision Sensor calibration. It appears to be flying normal again!

 

[garysmacman]

Now that's an interesting idea, but before going down that route - my update...

I recalibrated the forward and downward vision sensors, compass and IMUs this afternoon. Whilst looking at the photo of the front left vision camera, I noticed that the top cover of the drone was slightly separated from the body, so pressed down on it and it moved a fraction and "clicked" into place. I'd watched a Mavic tear-down video yesterday afternoon and the guy in the video commented something about the pressure from the top covers holding the connectors for the cameras (and antennae?) in place. Interesting. So, I waited for the rain to ease off this afternoon at home and took the Mavic out for a test flight. Take off to hover and OA radar sensors reporting obstacles in front about 4m away - the fence. Took the Mavic up to 3m so it was looking over the fence and no obstructions for 10m - radar all green. Full stick forward and my demented dragonfly tipped over and took off at what looked like normal speed. Hallelujah! I couldn't take it for a full run - not enough space, but I'll put it through its paces tomorrow in the work car park and test it, including RTH. Keeping fingers crossed that she might be good...

That's good news butterfingers! Do you have a link to the video you referred to? Thanks!!

 

[Butterfingers]

I watched two videos but this was the most detailed -

I took it out for a spin this morning and it was flying normally, so very happy! Not enough space to do a RTH test but will do that this weekend in a field near my home.