Search found 248 matches

by Mitteau
Thu Jan 04, 2018 9:38 am
Forum: Support
Topic: Client freeze
Replies: 15
Views: 2622

Re: Client freeze

Hi
In the starting log I can see "estimator 2". I suppose this means Kalmann filter. The cf is eqipped with the flowdeck for a perfect stability, except fast horizontal run, or the unstabilities we are talking about here.
Regards
Jean-Claude
by Mitteau
Tue Jan 02, 2018 9:17 am
Forum: Support
Topic: Client freeze
Replies: 15
Views: 2622

Re: Client freeze

Hi I confirm the phenomenon on my cf. For some reason, mainly a crash, but not only, the controller output instability on roll rate, as in preceding figures. I did not succeed trying to enter the instability by rapid turns around roll axis. Even rough and 180°. Once the desequilibrium is attained, i...
by Mitteau
Sat Dec 30, 2017 9:18 am
Forum: Developer Discussions
Topic: [SOLVED] What port/channel for proprietary messages of GNSS receiver?
Replies: 2
Views: 760

[SOLVED] What port/channel for proprietary messages of GNSS receiver?

Hi To go further in the evaluation of a GNSS receiver on crazyflie, to exchange with it, I want to use proprietary messages (UBX messages for Ublox). But I think it should be useful to use another port than console's. My question is: can I use port 6 (localization)? And which channel (the 7th) to av...
by Mitteau
Fri Dec 29, 2017 5:47 pm
Forum: Developer Discussions
Topic: Advance in the use of Ubox GNSS receiver
Replies: 1
Views: 440

Advance in the use of Ubox GNSS receiver

Hi! I finished (there still exists posibilities for some bugs) the pilot for gps receiver, and corresponding tab to show the parameters. The receiver is a MAX 8 board from Ublox. You can find the codes on my depository github.com/Mitteau/... The firmware version is the "etape1" branch of my fork of ...
by Mitteau
Fri Dec 29, 2017 5:18 pm
Forum: Support
Topic: Client freeze
Replies: 15
Views: 2622

Re: Client freeze

Hi,
I confirm the test made on roll rate. This graph shows the beginning of the freeze.
roll_r.jpg
I also confirm that a move by hand of the cf stops the phenomenon.
This instability does not appear on pitch control, until now.
Where does this behaviour comes from?
Regards
Jean-Claude
by Mitteau
Wed Dec 27, 2017 8:56 am
Forum: Developer Discussions
Topic: [SOLVED]Hurrah! First fix with Ublox
Replies: 7
Views: 1074

Re: Hurrah! First fix with Ublox

The main problem is the long delay to get a first fix (yesterday nearly half an hour). We should try to implement memorization of ephemerides. I am investigating this question.
by Mitteau
Wed Dec 27, 2017 8:55 am
Forum: Developer Discussions
Topic: [SOLVED]Hurrah! First fix with Ublox
Replies: 7
Views: 1074

Re: Hurrah! First fix with Ublox

The main problem is the long delay to get a first fix (yesterday nearly half an hour). We should try to implement memorization of ephemerides. I am investigating this question.
by Mitteau
Mon Dec 25, 2017 10:44 am
Forum: Developer Discussions
Topic: First notices about the use of Ublox GPS receiver
Replies: 0
Views: 662

First notices about the use of Ublox GPS receiver

Hi 1/ not surprinsigly, the fix takes a lot of time. 12.5 minutes for the last one. This needs roughly 30% of the battery, 2/ this means that we must implement some way to save (on the client's machine?) the ephemeris of the satellites at the shut down to get further hot fix, 3/ close to the board t...
by Mitteau
Mon Dec 25, 2017 10:25 am
Forum: Developer Discussions
Topic: [SOLVED]Hurrah! First fix with Ublox
Replies: 7
Views: 1074

Re: Hurrah! First fix with Ublox

Hi
I made a new post on my first conclusions on the use of Ubox GPS-Glonass receiver.
The fix is obtained with receiver place at 2-3 cm from the board. But if I put the receiver side by side with cf board, the fix seems to disappear.
Jean-Claude