Waypoints mission exactness

[DroneSteef]

In DJI Flighthub 2 I created a mission that I still needs to fly. I wonder how precise the route will be flown. Is there any one who can advise?

 

[brett8883]

In DJI Flighthub 2 I created a mission that I still needs to fly. I wonder how precise the route will be flown. Is there any one who can advise?

I wouldn’t count on it for precision. Even if it could fly it with precision, I’d still be sure to give plenty of room for error.

 

[GadgetGuy]

In DJI Flighthub 2 I created a mission that I still needs to fly. I wonder how precise the route will be flown. Is there any one who can advise?

Two things:
1. All your height measurements are relative to the launch point, so if you launch from anywhere other than the exact same launch point selected for the mission, elevations will be off, and intended barometric elevation changes have their own margin of error from the launch elevation. When you land, you'll see that the height is almost never back to exactly 0.
2. The accuracy of the route depends upon the accuracy of the GPS, which has its own margin of error, which depends upon the number of satellites in view, and its own inaccuracy, unless using correcting survey equipment. Golfers use GPS range finders, but they always hide measurements on the greens, stating "at the green" to hide how inaccurate they are, where people can easily see the detected position and where they actually are on the green. It can easily be off by 3-10 yards which is a 20 yard diameter circle of uncertainty! So, figure up to 10 yards in either direction.

In conclusion, the precision will vary. Others have posted overlapping video flights of the same mission, and they are close, but definitely not exactly the same! YMWV.

 

[Meta4]

In DJI Flighthub 2 I created a mission that I still needs to fly. I wonder how precise the route will be flown. Is there any one who can advise?

Only as precise as consumer GPS and the drone's barometric height sensor.
Don't use waypoints for flights that are close to obstacles.

 

[DroneSteef]

Only as precise as consumer GPS and the drone's barometric height sensor.
Don't use waypoints for flights that are close to obstacles.

I do understand but also want to understand how much tolerance I need to include....

 

[DroneSteef]

Two things:
1. All your height measurements are relative to the launch point, so if you launch from anywhere other than the exact same launch point selected for the mission, elevations will be off, and intended barometric elevation changes have their own margin of error from the launch elevation. When you land, you'll see that the height is almost never back to exactly 0.
2. The accuracy of the route depends upon the accuracy of the GPS, which has its own margin of error, which depends upon the number of satellites in view, and its own inaccuracy, unless using correcting survey equipment. Golfers use GPS range finders, but they always hide measurements on the greens, stating "at the green" to hide how inaccurate they are, where people can easily see the detected position and where they actually are on the green. It can easily be off by 3-10 yards which is a 20 yard diameter circle of uncertainty! So, figure up to 10 yards in either direction.

In conclusion, the precision will vary. Others have posted overlapping video flights of the same mission, and they are close, but definitely not exactly the same! YMWV.

Thanks for the response...it indicates that there is some tolerance but when I count in a certain percentage of
"safeness" this should be enough...

 

[DroneSteef]

I wouldn’t count on it for precision. Even if it could fly it with precision, I’d still be sure to give plenty of room for error.

than my question would be to understand how much "plenty of room" should be....

 

[Ralph thompson]

You don’t explain what yr doing that requires precision. For any surveying activity you need an RTK capable drone like the M3 Enterprise. With the Inspire 1 for non precise surveying work I used Autopilot SW (now defunct)for years and always allowed 50 feet as a rough safety margin. Before the mission, I’d fly to various points on the plan to confirm obstacle positions like tree tops, wires etc then make sure there was an additional 50 Ft for safety.

 

[mobilehomer]

It is in the manual. Look at the Specs section, it gives the GPS tolerances.

 

[Zbip57]

A couple of other things to watch out for and test beforehand. I've never used DJI Flighthub, so I don't know if these are an issue or not. Just something to think about.

If your first waypoint is some distance away from your takeoff location, does your drone fly a straight line from takeoff but only gradually increasing height to that waypoint? Are there obstacles to clear on the way? Or will it first take off straight up and climb to waypoint height, before then flying at altitude toward the first waypoint?

You can ensure it'll first climb/descend straight up/down by setting the first/last waypoint at a safe height directly above the planned takeoff location.

The second is, does the flight path go directly in a straight line between waypoints, or does it "smooth" the corners? If it carves a smooth arc short of the actual waypoint, you'll need to take that into account if you're planning to fly around any obstacles.

 

[DroneSteef]

You don’t explain what yr doing that requires precision. For any surveying activity you need an RTK capable drone like the M3 Enterprise. With the Inspire 1 for non precise surveying work I used Autopilot SW (now defunct)for years and always allowed 50 feet as a rough safety margin. Before the mission, I’d fly to various points on the plan to confirm obstacle positions like tree tops, wires etc then make sure there was an additional 50 Ft for safety.

I have created in Flighthub 2 a mission for my Mavic 3 and would like to understand the tolerance for the flown path created in this mission.