CCC rapid descent crashes

[dondec]

Does CCC record the position and HEIGHT of each way point?

Reason I ask is whenever I create and store my Points (in Angle mode, usually 10-20 ft up, SAVE, then run that List, it goes to the 1st Point and stops as usual. I Left Up Stick to get the program going. It starts descending immediately and crashes.

This has happened 3x now, it generally bounces the camera, breaks a prop and that's that. I dare not run it again, and maybe some rubber cushions above the camera have worked themselves lose as a result (another issue I post separately).

Just to be completely clear:

• I use Angle mode, without OA, to a position
• then yaw and angle down/up to center the camera on the subject
• then store + the point.
• Then I move to the next point and repeat.
• I usually put 6-7 points in my list then Save it.
• Finally, I return the H to about where the 1st point was saved
• then run the list and slide the screen switch over.
• It moves to the first point ok.
• I UP left stick and … boom.

Am I missing something? My H seems to work well otherwise.

Thanks

Don

 

[rdonson]

 

[dondec]

Yeah Ron, I watched your video a couple of times before I tried it. As you're not experienced my problem I presume that means the position and HEIGHT are saved at each point, so I'm not sure why starting a mission with Left Stick up causes it to descent to hit the ground.

Don

 

[AeroJ]

Yes, CCC does include the height in its position records, but there is aprox 3-6m of variation in that when playing back the path, so it is recommended to make your lowest point about 6m off the ground to compensate for this potential inaccuracy. But what yours is doing doesn't sound entirely like regular positional inaccuracy to me. Some questions...

1.Have you crashed every single time you have run a mission, or just for 3 out of many more attempts ?
2. In the crash flights, was the second waypoint lower than the first ?
3.What was the pack voltage when you initiated the mission ?
4. When did you last calibrate compass and accelerometer ?
5. Have you extracted the telemetry / flight log data from the ST-16 so you, us, or Yuneec can analyse the problem ?

 

[dondec]

Let me know exactly what files you need posted I'll be happy to upload them (as Zip file?).

As to your other points, it crashed hard 2 out of 3 times. The only "near mishap" (2nd try) came within inches of bottoming out. I am at a mostly level RC airfield and I'll try to attach the movie via OneDrive Link:
CCC 2nd Try.mp4

Satellites good, smart mode (Green) lights up if enabled, though I didn't use it or OA for CCC.

In the 3 case, I started off 20 ft up, with 2nd point also that high. It almost went straight down when I started the route.

Pack voltage on the 3rd hard crash was near full. Others don't know.

Photography and flight in Angle or Smart modes good:
Day4 01.mp4

Don

 

[AeroJ]

Hang on - aren't we meant to be in Angle mode exclusively for CCC missions ?!

 

[dondec]

Yes, please read original post... used only Angle mode. Smart mode works just indicator of good GPS link.

Don

 

[AeroJ]

Yep, my bad, misread that

 

[Dustoff]

Did you try making a different ccc route and testing . Maybe something in the second waypoint got messed up and did not store the altitude correctly .

 

[CraigCam]

This was my original issue back in 2015 that required Yuneec warranty repair. Are you still under warranty? I was told it was the IMU and compass/GPS module not working together properly.

 

[Dustoff]

You look pretty low to the ground in the clip . Have you tried being up a little higher . And any clips showing it going down.

 

[dondec]

all 3 were different. No crash vids. Ironically the clip provided (2nd try) had points about 8-10 feet high... and that was the near miss. The others were higher, and crashed into the grass when I started, at about the same place in that field.

Can the height be controlled in some way after the route is started?

Don.

 

[AeroJ]

Can the height be controlled in some way after the route is started?

Alas, no it can't. The near miss is perhaps to be expected if your waypoints were that low, but I can't see anything you are doing that would make it just drop and crash like you describe when you start the mission... let's hope that is a mystery the telemetry can reveal the answer to... I'm not kitted up to review that myself, but plenty here are, and I will defer to them to tell you exactly which files they need...

 

[CraigCam]

Again, this is an internal flight control error. It’s a known problem. When I called Yuneec post my exact same problems, they issued a RMA immediately. My crash did the same thing and ripped my camera wires apart. It’s unacceptable behavior that’s not your fault and makes your ship a safety hazard.

 

[dondec]

Thanks CraigCam, I am under warrantee so lets see what happens next.

 

[CraigCam]

Good luck.

 

[Dustoff]

Good luck , this also serves as example to check all all modes of operation early on under warranty .

 

[Tuna]

Okay....

Yes, the CCC routes record the height of each point. Height is *relative to your take-off position*. When you first launch the H, it resets its altitude to be zero. So when you fly to the first point and store it (as say 10ft high), it means the H thinks it is 10 feet above the point it took off from. Every additional waypoint is also relative to the take-off position.

Now, the Typhoon (like most drones) uses a barometer to measure height. It is... not accurate. Changes in air pressure (including gusts of wind) will make the drone rise and fall, or record different altitudes. The same goes for changes in temperature. This is a problem for all drones that don't have commercial/redundant GPS systems. Over time, they drift. It's not uncommon for you to land the Typhoon and for it to think it's 10 feet below ground! If you keep your machine in an air conditioned car, then take it out into full sun, you may be particularly affected by altitude drift as the barometer warms up during the flight.

This means that if you take off, plan a CCC route that is relatively close to the ground and then immediately try to fly it, you can find that the machine goes up or down. Before you start flying the route, check what altitude the machine thinks it's at. If it's out by more than 10ft and your waypoints are only 10ft from the ground... you're going to have a crash.

It also means that if you took off from the top of a hill, recorded a CCC flight, then later came back and took off from the valley below - when you fly the CCC route, it will crash. It thinks that the CCC route is above the original takeoff point (the top of the hill), so taking off from somewhere lower will fly at that lower height... into the ground.

The recommendation is to either build in more leeway into your CCC route, or to land, stop the motors and then restart between flights to ensure the most accurate barometer results. If you're re-flying a route, take off from the same location (or altitude) as you originally flew from.

One other thing to remember is that the CCC route is flown as a curve. That means that if you have a part of the route that has a sudden large change in altitude, the Typhoon may swing the other way to smooth out the transition. So if you have three waypoints to make a route that goes along and then vertically upwards, the Typhoon will actually dip down as it approaches the second waypoint so it can swing up smoothly into a vertical climb. Always allow plenty of space around a CCC route as it is not flown as a series of straight lines. Always have one finger on the 'abort' button just in case you misjudged things.

Finally, it's possible (but relatively rare) you have had a hardware problem. Without reviewing both the CCC route you recorded and the flight logs, it's hard to tell. When you're flying, it's worth paying attention to the telemetry on screen to see if it looks 'realistic' - is it giving sensible numbers for altitude and distance, is the green arrow pointing the way you expect, and do you have enough satellites to be getting a reliable fix?

 

[hatfield]

Always have one finger on the 'abort' button just in case you misjudged things.

That would be a good use for the aux button.

 

[Dr Delta]

That would be a good use for the aux button.

sure, funny nobody got to that point up to now.