Minimum Practical Orbit Radius
The other week in a post a discussion arose around an orbit that Bob Scheffler was having problems with, this particular orbit had a very small radius of 0.5 feet, so I asked Jim what the minimum radius was to which he replied:
We haven’t decided yet but certainly greater than zero. Feel free to do some tests and suggest something that still results in a good user experience.
So I took the challenge up and the following video is what i came up with
Comments
13 comments
Martin I do not know if it makes a difference but I had generated my original troubling orbit with "On-The-Fly". I know it shows an orbit of .5 feet but it was actually about 4 feet. I did the mission by flying right up to the pole and marking center then backed off a measured 2 feet. Why the plan says .5 feet I do not know, maybe it has something to do with the GPS accuracy. I also performed test similar to yours, using on-the-fly. I used a construction cone and hovered over the top to generate a center I then, like you, went out various distances. I went 3, 6 and 10. I then threw in speed, I went 1 mph 2 mph and 4 mph. My 3 foot orbit ended up looking like your spider like lines but the rest did not. At 3' and 1 mph the drone did fine staying in the lines but as I sped up it got less accurate. And all the rest tests were good. I have not been able to do much testing because every day we have been having some stiff winds.
Bob, I may well have a play with speeds as well, I actually played with the rotation rate in preview last night, to track that center at the 3.3 feet at 5mph it needs to be set 40deg/sec and I'm not trying that, weather is not good here either
Just remember that the accuracy of GPS is usually only about 16ft - so anything less than that is going to give unpredictable results.
Barry Houldsworth, totally agree which is why i mentioned at one point during the video, that although it wasn't tracking very well at the smaller radii it was doing ok considering GPS accuracy
I have heard that 16 ft accuracy many times when dealing with drones, is this also the case with boats using GPS chart plotters?
Bob Scheffler, give this a read https://www.gps.gov/systems/gps/performance/accuracy/
Def need to slow way down for very tight Orbits. If you fly closer to 1kph how tight can you get?
I'll have play Jim McAndrew
Fun video Martin, and great shirt! : )
I have often thought about putting a drone through the paces like this just to test the boundaries.
Cheers Tony, I'm going to see what I can reduce the radius to at slower speeds, that should be fun
Ok Jim McAndrew I've now put together another video to show the minimum radius that can be achieved along with a reduction in speed which can be found here https://youtu.be/7tBar77ds1w
Alejandro Dabroy This was the original Orbit test https://app.dronelink.com/ofbqZAZfv4ssKooRFqS9/Iev0ZWdX58Rt4rEsoJ3v/plan/ZFR6SImuAwvN4S3cFVyO
And this was the one for minimum radius & speed https://app.dronelink.com/ofbqZAZfv4ssKooRFqS9/Iev0ZWdX58Rt4rEsoJ3v/plan/0r4tHDhjlsnYtJzNR0bh
Thanks, Martin!!!
Please sign in to leave a comment.