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flight altitude

Dear All,

I am using phantom 4 pro with pix4d capture android. my start level is 876.00 m. i am arranging altitude 80m which makes 876.00+ 80= 956.00 m altitude. our tallest tower crane top level is 953.00m. So my flight level must me 3 m higher than the top of crane. Unfortunately during mission drone stop when passing on crane, i cant see from ground how close it was to the crane but i can say it was not the highest point of crane, it was even lower part of boom and drone hang itself on air for sometime, after i tried to rise it up or move and after some try it release ıtself and continue mission. So my question is, what is the obstacele sensor distance for p4p? it can fly lower then 90m, altough i see on app flying 90m? is there any calibration or etc that i have to do with dji app?

 

Thanks

 

Yunus Emre

 

At the moment we have not extensively tested the obstacle avoidance feature. 

However, it is not expected to be operational during an autonomous flight, meaning when flying a polygon, grid, double grid, or circular mission with Pix4Dcapture. As a consequence, it is recommended to make sure the flight plan is defined in a clear area and high enough to avoid obstacles. Let us know if you have any additional feedback on this topic.

Please keep in mind that flying so close to objects is forbidden in many countries. Make sure to follow local rules and regulations.

Best,

Dear Blaz

Thanks for your comment,i remember you commented same when i asked this issue before. i tested 3 times and i can say that P4P while fliying with pix4dcapture android, stop itself when there is a obstacle on the way. That is why i am asking to all people in here who is having real experiences at site, if anybody knows why it is happening even you are saying you" have not extensively tested the obstacle avoidance feature." By the way thanks P4P to save me from a crush.

Flying so close to objects; that was my question?, i didnt want to fly close, according to calculation my drone had to be 3 m higher than the closest tower crane. I am flying in a private zone by the way, its our construction site. pix4d capture shows i am flying 80 m high, but in reality it is not. the distance from my take off level(876.00) and top of crane is(953.00) 77m. i am arranging my flight parameter as 80m altitude. it has to be 956.00 but as you can see from below pic. my flight altitude on the tower crane is 950.38, which means i am not flying 80m altitude i am flying 74.38m altitude according to math. So my question again, how can it be? what i am doing wrong? It will be appreciated if anyone can comment about that.

Thanks

Yunus that’s because the GPS integrated in the Phantom 4 it’s not accurate enough for those close calculations.

What normally I do it to manually fly the drone (with DJI Software) to the highest spot in the site. Then look at the height showing in the controller and then set the height of my flight at least 5 meters over that obstacle.

Hope that suits you

@Yunus, thank you for the feedback about obstacle avoidance. 

As @Jorge already mentioned, the sensors integrated into the drone are not accurate enough and offsets of few meters, especially for the z-axis, are expected and should be taken into account when planning the mission. 

 

 

@Blaz I too can confirm that the obstacle avoidance on the P4P does indeed work whilst flying in Pix4D Capture. I didn’t mean to test this, however due to a slight miscalculation over the height of a chimney I found out it does indeed work! This is a good thing, it saved a crash.

@Yanus as per @Jorge above the Z on the P4P GPS is not very accurate, certainly I’d not rely on it to avoid a crane. Your best option would be to fly up to the top of the crane in DJIGo4, check what height your aircraft thinks it’s at and then plan your mission 5m above that height. Relying on calculations and GPS co-ordinates will lead to trouble for you.

1 Like

@keith thanks for advise, i will check with DJIGo…

@Keith, thank you for the feedback! We are glad to hear it worked. Are you using Android or iOS version?

@Blaz - I’m on IOS version. It will probably work with Android too. I was having trouble with my Ipad a while back where DJIGo kept crashing so I was flying without just on the remote. I tried flying into things with no app running, the collision avoidance still worked, so I am fairly sure that it is built into the aircraft’s hardware… I could be wrong though, so don’t blame me if your Android powered device hits a crane!

@keith i am using android, it works on it as well.