Hello,

Recently my P4P+ started to behave strangely. Does not matter how high the drone flies or which direction it goes, VPS sees something very close below (0.1m - 0.7m) and drone suddenly slows down considerably then speeds up again. Same goes for landing. When descending with the throttle full down with it acting like that - showing 0.1m - 0.7m and slowing down - it might decide that it has landed and turn the motors off. Any solutions? The drone never hit the ground hard or was damaged.

Can someone help me? VPS glitch repeats every single time I fly

Are you flying with the sun facing the vps sensors? (it might act as the way you described)

Have you tried to calibrate the vps using latest assistant v2?

If a calibration doesn't sort it, get in touch with DJI support, and let us know what happens.  You should get it fixed, under warrantee if necessary, since as you say, if it thinks it has landed on something that doesn't exist then it may fall.

Do you have anything added under the aircraft such as a gimbal guard?   It is probably the ultrasound bouncing off something, or just a noisy sensor...

Thank you for response. I've never did a VPS calibration. I do not have anything attached under the drone and it works pretty flawlessly apart from that occasional VPS thing.

Not sure the VPS calibration calibrates the ultrasonic sensors, it might be under IMU calibration, if it actually exists which I'm not sure of...

The VPS calibration calibrates the 4 vision cameras, the issue will be with the ultrasonic sensors.

Also do you have accessories on it? Foot extensions, gimbal guard??

Mobilcams Posted at 2017-6-26 11:00
Also do you have accessories on it? Foot extensions, gimbal guard??

No, absolutely nothing

You are talking 10-70 centimeters here. Where do you get these numbers from? From the radar chart?
What happens if you switch off Vison Positioning? You need to approch this issue by activating/deactivating the settings under 'Visual Navigation Settings'.

Seems you have flown before without problems - but did you remove the protection stickers from the sensors???

Eric13 Posted at 2017-6-26 13:49
You are talking 10-70 centimeters here. Where do you get these numbers from? From the radar chart?
What happens if you switch off Vison Positioning? You need to approch this issue by activating/deactivating the settings under 'Visual Navigation Settings'.

Those numbers appear in red on P4P+ controller screen and drone slows down. If I switch off VPS, it's all good and well... VPS is deactivated so no more any glitch. I removed all stickers before my very first flight. Now I have spent 7 hours + with drone in the air.

papartis Posted at 2017-6-27 00:59
Those numbers appear in red on P4P+ controller screen and drone slows down. If I switch off VPS, it's all good and well... VPS is deactivated so no more any glitch. I removed all stickers before my very first flight. Now I have spent 7 hours + with drone in the air.

Did you visually check that the four downward facing sensors ( 2 vision and 2 ultrasound) are actually clean of any dirt from the backwash during takeoff/landing?  Also, on what kind of surface does the glitch happpen? Reflective, monochrome and not sufficiently detailed surfaces can impair the VPS sensors...

Antonio76 Posted at 2017-6-27 02:48
Did you visually check that the four downward facing sensors ( 2 vision and 2 ultrasound) are actually clean of any dirt from the backwash during takeoff/landing?  Also, on what kind of surface does the glitch happpen? Reflective, monochrome and not sufficiently detailed surfaces can impair the VPS sensors...

Never looked at those sensors but I am going to do it tonight.  The glitch happens everywhere - it might be the grass on the ground, soil, road, street, building - no matter what. It's not constant though, it does not happen sequentially, just randomly. I can fly 100 meters above, I can fly 15 meters above the ground - it still happens at some point.