Self stabilizing using the 3-axis accelerometer?

Discussions and questions about the Crazyflie Nano Quadcopter
ahorvat
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Posts: 4
Joined: Sat May 18, 2013 10:46 am

Re: Self stabilizing using the 3-axis accelerometer?

Post by ahorvat » Sat May 18, 2013 10:50 am

I'm also having some issues getting the hover mode working. I've cloned, built and flashed the firmware.
Using PS3 Mode 3, clicking the O button seems only to toggle the hover mode off, at which point the quad just drops out and motors are unresponsive.

Am I missing something here?



willminers
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Joined: Sun May 12, 2013 12:50 pm

Re: Self stabilizing using the 3-axis accelerometer?

Post by willminers » Sat May 18, 2013 12:27 pm

I was getting that, ahorvat, are you sure you built the right version of the firmware? I had the right branch of the pc client, but not the correct firmware, so the hover mode was just acting as a kill switch.

The problems I am having with the hover mode are that once I turn it on, it just flies up until it hits the ceiling, and I can't seem to reduce the altitude.

pablo_paul
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Joined: Fri May 10, 2013 8:26 pm

Re: Self stabilizing using the 3-axis accelerometer?

Post by pablo_paul » Sat May 18, 2013 4:13 pm

I'm just cloning the hover branch I think the original link given was for the cloned bitcraze branch!

ahorvat
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Joined: Sat May 18, 2013 10:46 am

Re: Self stabilizing using the 3-axis accelerometer?

Post by ahorvat » Mon May 20, 2013 12:56 pm

At the time I cloned, the hover branch was already merged into the default, but something was apparently wrong. Cleaned and rebuilt the firmware.

Now I have the 'hover into the ceiling' behaviour that I've heard about...yay. So I guess this needs a bit more work. Anyone had any real success?

mjc506
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Joined: Wed Feb 20, 2013 1:41 pm

Re: Self stabilizing using the 3-axis accelerometer?

Post by mjc506 » Mon May 20, 2013 3:16 pm

I re-coded the hover 'thrust control' part of Phiamo's code here: https://bitbucket.org/mjc506/crazyflie-firmware

I still need to tweak the PID parameters (and work out a sensible D part) but so long as the set point isn't too far away, it hovers quite happily.

I'd recommend holding on to your cf at your desired height first, then switching hover mode on. The props will then start to spin, and when you let go the cf will drop a bit, but then should start to recover.

bhuism
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Joined: Thu May 09, 2013 8:51 am

Re: Self stabilizing using the 3-axis accelerometer?

Post by bhuism » Tue May 21, 2013 1:49 pm

I'm very excited about pressure driven thrust! I'll give it a try, can u put a binary up in your bitbucket or do I need to compile it myself? will you pull your changes to the main repo later?

rmirwin2
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Posts: 51
Joined: Mon May 13, 2013 6:06 pm

Re: Self stabilizing using the 3-axis accelerometer?

Post by rmirwin2 » Wed May 22, 2013 4:14 am

Also had the ceiling thing until I got your last contribution (b3f0802) today, Matt.

My Crazyflie is hovering now!! :lol:

Still some oscillation in the altitude but it's very close. Amazing!

Phillip, Matt, everyone, great work, sure is fun! Thanks!

Rich
VGer's v1.7.1 frame, 10DOF Crazyflie, Wireless Xbox360 Controller, Virtual Machine on VMware/Windows 7

mjc506
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Joined: Wed Feb 20, 2013 1:41 pm

Re: Self stabilizing using the 3-axis accelerometer?

Post by mjc506 » Wed May 22, 2013 10:15 am

It needs compiling first at the moment, once I've got it working nicely I'll stick up a compiled blob and do a pull request.

Rmirwin2, are you using the standard PID coefficients? I think they still need tweaking, but yeah, they're not too far off I think.

rmirwin2
Member
Posts: 51
Joined: Mon May 13, 2013 6:06 pm

Re: Self stabilizing using the 3-axis accelerometer?

Post by rmirwin2 » Wed May 22, 2013 3:23 pm

I suspect they are yet the standard ones as I haven't looked for them or seen an update for them.
Do you plan to post a good set?

Again, thanks for the work here. Really makes the Crazyflie easier to handle!

Rich
VGer's v1.7.1 frame, 10DOF Crazyflie, Wireless Xbox360 Controller, Virtual Machine on VMware/Windows 7

mjc506
Beginner
Posts: 13
Joined: Wed Feb 20, 2013 1:41 pm

Re: Self stabilizing using the 3-axis accelerometer?

Post by mjc506 » Wed May 22, 2013 3:53 pm

You can fiddle with them in the 'parameters' tab :)

Once I find a good set, I'll push the changes to bitbucket and provide a compiled .bin

Phiamo's done some work with my code too, but I'm still at work so I'll check it out at home :)

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