Waypoint mission problem
- Thread starter shb
- Start date
The symptoms are the same, and BKushner asked about any similar behavior, so he would clearly be interested. Both are acecdotal. While shb may not be very articulate about the problem, I have no reason to doubt that what he is reporting is happening. He programs a waypoint elevation of 150 feet followed by another waypoint of 100 feet, but the drone instead descends to 50 feet, 50 feet lower than programmed. BKushner is reporting a 50 foot drop in elevation at altitude with no stick inputs, as documented by the log file. It's the same behavior in both cases. One is from multiple Waypoint Missions that resulted in two crashes, and the other a crazy independent descent without stick inputs. Something is happening to three different drones, as shb had the same problem with two. He's also right about not many people programming waypoint missions from a map, with large elevation changes that are overshot, and occurring out of signal range, on a regular basis.
Not by us, but by DJI, if he sends it in, but his flight logs on his device that he doesn't want to share (even though in a foreign country), also contain most of the same critical flight data. Both PhantomHelp and AirData can analyze those flight logs on his phone to corroborate the unprogrammed descent, just like BKushner did, showing 50’ of descent with no stick inputs!
This really isn't a motion sensor problem, unless you are expecting the motion sensors to prevent the drone from descending into the ground or into a tree from the excessive descent, which is really a separate issue, and a valid one, but unrelated to why it is not maintaining proper altitude relative to the planned elevations, which are all relative to each other, and why a drone without any stick input would descend 25-50 feet during forward flight. This is concerning!
I'm using fly on an android tablet for all my waypoint flights. Why bring up what rc pro uses? Did you see the picture where it says google?
You left out that critical fact. You are also posting in the Mavic 3 Pro thread. The Mavic 3 Pro is only sold with either the RC Pro or the DJ RC, neither of which have or can be used with Google maps. The Mavic 3 Pro also cannot be purchased with the RC-N1 controller that you must be using, and DJI doesn't yet offer a Mavic 3 Pro drone only option.
This is why you are being told that the maps are not Google. You found a Google Map loophole. You are flying with a unique combination which may explain your unique results, along with the fact that you are also not following DJI's recommendation to pre fly all waypoints for accuracy. This also explains why your RC is unpaired from the bound RC, limited you to 5 flights before needing access to the bound RC, because you, yourself, unpaired the RC it was sold with.
For someone that is supposedly warning us about your findings, repeatedly calling DJI stupid, you are withholding critical details, while posting snarky replies to anyone asking you for clarification and providing contrary information. You aren't helping us. You are ranting about DJI, which is another violation of our Community Guidelines.
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Not by the owner, because they are encrypted, only DJI can read them. Stupid again!
DJ Wes
Well-Known Member
While I hesitate to get involved with such a toxic person, I think I may know what is going on.
The Mavic 3 waypoint implementation uses a Bezier curve to define the waypoint path where the curve passed through the control points. Consider the mission pictured below if it were rotated into a vertical plane. One can see how when traversing from waypoint 3 and through waypoint 4 that the path continues to reach a lower altitude.
Without seeing any details on the OP's mission, this is only a guess. However, depending on the configuration of the OP's mission, this may explain the apparent drop in height below the lower waypoint.
The Mavic 3 waypoint implementation uses a Bezier curve to define the waypoint path where the curve passed through the control points. Consider the mission pictured below if it were rotated into a vertical plane. One can see how when traversing from waypoint 3 and through waypoint 4 that the path continues to reach a lower altitude.
Without seeing any details on the OP's mission, this is only a guess. However, depending on the configuration of the OP's mission, this may explain the apparent drop in height below the lower waypoint.
when you plan a mission you only get to see it,and plan it, in two dimensions. you do not get to see the vertical dimension. so if they're going to do that, they should, give you another view, in the vertical dimension, so you can see if it's going to go below the altitude of one of the waypoints. but I see your point it's a valid point. You must be highly intelligent! Unlike DJI!
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But you're not getting any information stored on your phone it you're out of signal range.
True, and a valid point, for those sections of your mission where the drone is not connected to the RC. However, the issues you are raising about presetting a first waypoint elevation of 150 feet at one waypoint, and an presetting an elevation of 100 feet at the second waypoint, and when flying the mission, it arrives at the second waypoint at an elevation of 50 feet instead of 100 feet (50 feet lower than programmed), should be able to be replicated on a simple preprogrammed test mission while continuously connected to the RC, so the flight data can be analyzed to figure out exactly what is causing the problem. Are you up for trying to replicate the problem within signal range, anywhere that you don't mind revealing the location?
Right now I'm on a vacation so I really don't have time for experiments. When I get back to the Philippines I could try that. Maybe I will investigate that Bezier curve a little. What I do to defeat that, when I'm going around corner, say in a urban environment, with tall buildings, is I put many waypoints close together, when I'm going around a 90° turn with tall buildings, and that way it doesn't hit the building's. I can do the same thing in the vertical plane. So at the low point, put three or 4 waypoints close together.
I don't understand exactly what you're saying, but you can see what's happening, just by doing a waypoint Mission, and imagining that that mission is flipped over on its side, and you will see, that it will go down further sometimes than any of these lowest waypoints. Just like if you're headed due north, and turn east, it will actually curve west, before it goes east. Just imagine that in the vertical plane.
So you are now convinced that @DJ Wes 's possible explanation above completely explains all your issues? If so, then it is operating as designed, rather than acting completely unexpectedly. However, your description sounded far more extreme, overshooting the 100' waypoint setting by a full 50'. Were you perhaps exaggerating originally for dramatic effect?
