Gimble Pegs Straight up on way point mission

I have been using Litchi for several years and never had a problem. today I started a new way point mission (pre planned in mission hub) and as soon as it started the gimble pegged straight up and stayed that way. I checked the POI and that was set correctly in the actions. The drone (Phanton 4 V2 and Ipad mini) worked correctly in DJI go 4 with proper Gimble control. Anyone ever have this issue before? I will do a few additional tests on some older missions that worked previously and see if the issue is with the new mission or something with the software / drone. Any suggestions would help.

UPDATE: I checked an older mission and everything worked correctly in Litchi, so perhaps it is just a glitch in the most recent mission I created. Everything looks correct, but something is off.

If you can’t figure it out, share your mission so that we can take a look.

I observed this exact gimbal anomaly recently when I sent my Mavic 2 Pro on a long-distance range test flight over a sprawling palm tree plantation. The drone was approaching the outer limit of RC signal about 3 miles out over a tropical swamp forest fringing the plantation when suddenly the camera pitched 90 degrees vertically down.

Unsure whether the drone had suffered a raptor strike from behind, I hastily punched the RTH button, to which the drone responded normally by climbing to the RTH height of 240 feet and pivoting to face home, while I frantically worked the camera pitch thumb-wheel to raise the camera view upwards from its navel-gazing position. Long story short, the gimbal action was erratic at first, but as the drone flew back into a more reliable RC signal reach I was able to adjust the camera back to its usual minus 11-degree downward tilt.

The cause of that camera dance had been explained to me by an experienced drone owner writing in the Mavic Pilot’s forum after I wrote in to describe when such a camera abnormality occurred for the first time at the furthest reach of an earlier range test flight I ran with my older Mavic 1 Pro. Turns out that on very long flights where the RC signal breaks up to become intermittent, the signals that determine the camera’s downward pitch angle can become garbled, and thus contain erroneous instructions which cause the camera to go haywire.

For me, the workaround solution that reduced the frequency of such camera jitters was simply to power off my RC controller during the departure leg of any long-range Litchi waypoint missions that I launch, and then only turn the RC controller back on when Litchi’s estimated flight time figure predicts that the drone is inbound and not far away. Obviously, my solution would NOT be practicable if the drone is under direct pilot control as opposed to being under fully autonomous Litchi control flying waypoints far from home.

If in your instance the drone was under manual control during the flight when you noted the camera pitch erratically, I would suggest a full calibration of the camera and other aspects of the drone, after which your flights should be kept a little shorter in terms of maximum distance from home base, so as to maintain a strong RC signal throughout.

Thanks, in my case the flight was close range, and the gimble went UP (looking toward the props) as soon as the mission started. In flight I had no gimble control. Returned to home and flew the mission manually in DJI go4 and everything worked normally. I subsequently flew an older mission in Litchi at another location and all was normal. I can only assume that there was some type of strong interference or magnetic material at the initial take off location that effected the data upload. The Litchi Parameters were all correct and rechecked. Does Litchi use Actual elevations (an onboard altimeter) or is it pulling from google database. The Mission POI was set to 0 feet above ground, but placed on top of a 5 story building. Takeoff was from the ground adjacent to the building.

If the “Above Ground” option is checked in the Mission Hub, elevation data will be used to create the mission. For the height calculations to be correct, the first waypoint must be at a location that shares the same elevation at the take-off location. Neither the Litchi nor the drone has any way to determine its altitude above ground during a flight.

Altitudes are always in reference to the take-off location. Neither the Mission Hub nor any elevation data will know how tall a building is. So, the statement “placed on top of a 5-story building” is misleading and irrelevant.

“On board a drone, a barometer is used to control the flight height by detecting the atmospheric pressure change.”

Hi Wes, are you saying that the drone doesn’t know it’s altitude above sea level or are you saying that the drone doesn’t know how high it is above the ground below it?

Both. The drone only knows its height above (or below) the take-off location by the difference in barometric pressure.

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