SOLVED: Origin/Home altitude not being reset on arm/takeoff? Rangefinder use in guided mode?

ArduCopter Copter 4.3
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1

Greetings all,
Log 20241120_WB02_Log19_Flt1.bin - Google Drive

I am trying to figure out why this system did not reset it’s origin or home altitude to 0 after arming or after takeoff. The system has a rangefinder, and while it wasn’t configured to be used in the EKF, I understand that it is used directly by the altitude controller to determine target altitudes in alt hold modes. In this case it was launched in guided mode. In guided mode, is the only way for the rangefinder to be used is by incorporating it in the ekf, either as a secondary or tertiary source, or with the EK3_RNG settings? I am attempting to fly close to the ground and for testing purposes I am constrained in how high I can go. There isn’t much room for error, so erroneous and fluctuating altitude estimates are problematic, and we are doing guided mode testing.

Thank you for your help!

Edit: Linked the wrong log, the correct log is linked

Solved:
I had left “Send home position” enabled on QGC, which was interfering with initializing the home position altitude at launch. This was an error, and ceasing this restored the “set 0 altitude initialization at launch” behavior

2

Do not set the home altitude to 0. Use 0,1 instead.

3

I’m sorry, I had the wrong log uploaded, can you review again?

4

I see, same problem here, mav cmd do set home is used incorrectly

5

Any chance you can speak to the use of the rangefinder for guided mode?

6

Are you sending the right type of altitude in guided mode commands? Should be sending terrain-altitude, not relative or absolute.

7

Can you tell me more? During normal operations I expect to be at altitudes where the rangefinder won’t see the ground. During testing, I’m restricted to only about 15 feet with overhead obstacles. Unless I don’t understand your suggestion

8

Maybe I am mistaken here. I thought you were trying to fly at low altitudes (within randefinder range)?

9

Actually, I don’t understand what you mean, do you mean set the home altitude to 0.1?

10

I am trying to test at low altitudes, and actually just change altitude, not lat/lon. I am trying to figure out why my reported altitude is drifting around while hovering within 15 feet of the ground. I expect to issue relative altitude change messages, even if close to the ground. I expect that the rangefinder would be used to help fix the altitude estimate when close to the ground, but not that I would need a special command to change the altitude in a “terrain aware” manner.

I’m sure my expectations are wrong about what is really going on

11

I had left “Send home position” enabled on QGC, which was interfering with initializing the home position altitude at launch. This was an error, and ceasing this restored the “set 0 altitude initialization at launch” behavior

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