RTL Speed Issue

While testing RLT, Smart RTL and Waypoint Navigation I discovered that the Speed was set to about 2m/s and I could not get it to go any faster despite RTL_SPEED and WPNAV_SPEED both being set to 700 cm/s. Below is links to logs and parameter file of an RTL Test

Thanks

David Ardis

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Hi David,

I’ve had a look at the logs and I see what you mean about how it’s not obeying the RTL_SPEED.

I’m unable to reproduce the issue in SITL so I’m wondering if you have any more details of what happened during the test. I see there is a do-change-speed command in the mission but as far as I can tell the mission wasn’t run before RTL was initiated. I’m also wondering if it’s possible the RTL_SPEED or WPNAV_SPEED (or other parameters) were modified before or after the vehicle was switched into RTL mode… I’m wondering in particular if there were any parameter changes made while the vehicle was flying… although I would expect these changes to show up in the logs and I don’t see them.

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Randy

This all started when I needed to do a Smart RTL from a few hundred metres from the Home position. The Quad did come back but really slowly, Checked the Wiki to see if I had missed anything and but all appeared to be set correctly. Tried Smart RTL again, the Copter did come back really slowly, Then decided to just try an RTL which climbed to 30m and returned really slowly (This is the log you have seen). A bit more head scratching and though I should run the mission as this would use WPNAV_SPEED and a short mission was already loaded into the copter the only thing removed was the DO_Change Speed, When I started the mission the speed was about again about 2m/s.

The Copter has no telemetry radio and the the channel 6 trim is not set to adjust waypoint speed.

During some of the test I did try and adjust RTL_Speed but did not make any difference.

Thanks for your help
David Ardis

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Don’t know if it is related but in my flight where i had troubles with GPS my RTL speed was very slow and “bouncy”. Maybe a completely different thing but worth checking.
In the attached log right after the RTL initiated by radio you can see RTL speed be very bouncy and very slow (it should be 8m/s as wpnav speed since rtl speed is set at 0)

https://drive.google.com/open?id=1HtRncZHWJpd0mDIbY2hCR8KQAQz3GUGb

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Did few more tests today and something very strange happened set WPNAV_SPEED to 800 cm/s and all worked as expected, then set WPNAV_SPEED to 700 cm/s again everything worked as expected. changed WPNAV_SPEED back to 700cm/s and started the mission the speed did not go above about 200cm/s.

I have logs of all the flights if required

David Ardis

Hi David,

I’d like to see the dataflash logs if you’ve got them. Basically we just need to be able to recreate the problem in SITL (the simulator) in order to figure out the details of how it’s happening. I’m reasonably confident the issue should also show up in SITL if we can follow the same steps.

Randy

As requested below is link to several test flights at 800cm/s, 600cm/s and 700cm/s

I aborted the 700cm/s flight as it was going to take too long

800cm/s https://www.dropbox.com/s/jrb6lnajfwj35k9/2018-12-30%2015-20-02.bin?dl=0
600cm/s https://www.dropbox.com/s/5y0kfqmj51f9iap/2018-12-30%2015-35-08.bin?dl=0
700cm/s https://www.dropbox.com/s/t72wcxenqlu3z2q/2018-12-30%2015-50-06.bin?dl=0

Thanks

David Ardis