What worked for me in the end, was to first understand state observers (e.g. Luenberger observers) and then consider a Kalman filter as an optimal observer, where the observer gain is the steady-state Kalman gain.
The whole duality between state-feedback design and observer design -- and LQR and Kalman filters. Then it made sense :-)
Awesome! I attempted the same approach, but after discovering a cheap gas concentration sensor (MQ-135, tunable to CO2) I abandoned the audio approach for a minimum of data processing. I get very accurate bubble detection and highly recommend it :-)
Ooh that sounds very interesting, I'd be interested in how that works, do you put the co2 sensor near the airlock and notice 'peaks' of co2 from it, when bubbles come through.
Or is the sensor in the fermenter itself and you're kind of measuring the pressure?
I put it near the airlock and detect peaks. For now, the most valuable information I extract is when the fermentation starts and stops -- with notifications on my phone :-)
I built a Prusa i3, with most parts 3D-printed on another Prusa i3. I mainly use it for university projects, printing actuators and cases.
Last semester we printed a model boat, about half a meter long, outfitted it with a printed a linear actuator to control the rudder angle, and - as our semester project - built an autopilot for it. Great fun :-)
I did and am very pleased. Unity actually works. Suspend works. It's fast and smooth.
My only problems were in installing it on a new laptop. I wanted to dual-boot Windows 8 and Ubuntu. No dice. Turn off signed booting, wipe the weird set of partitions Sony uses for Win 8 and then things went smoothly. I'm keeping the old machine for Windows 7.
Did you upgrade or format/install? I'm pondering it now. I've had quite a few system hangs lately and am wondering if I should even attempt the upgrade to 12.10
Did an upgrade cycle from 10.04 through 11.10, installing every release. Did a clean install at 12.04. Have upgraded that to 12.10 and now 13.04. I will not say there were no issues, but I never faced data corruption or unable-to-boot issues during this time. What I did face though was random errors and broken packages. But I did not document those erors, so I cannot go into any specifics.
I upgraded from 12.04 LTS and I had a few niggles - the configs for Compiz were messed up and the AMD proprietary driver wasn't working, oh and grub got nuked.
Ultimately, blowing away the compiz configs (rm .compiz*), a dpkg --configure -a fixed the AMD driver and boot-repair from a Ubuntu LiveCD was a wonderfully simple way to redo grub.
Not painless but not particularly difficult to fix.
I'd imagine most people on 12.04 will stick with it until 14.04 comes out. 12.04 is an LTS release, and is supported for 3-5 years from the release date where 12.10 through 13.10 are normal releases, and are only supported for 9 months from release.
However, anyone on 12.10 should be able to "do-release-upgrade" and upgrade themselves to 13.04.
I wanted to stay on 12.04, however 12.10 came with the option to encrypt your whole hard-disk straight from the installer with dm-crypt, which is much better than ecryptfs, at least when it comes to performance. And manually encrypting your hard-disk with dm-crypt can be quite painful.
The downside of that is that 12.10 and non-LTS versions in general only get bug fixes for critical bugs, otherwise the bug fix is the upgrade to the next version, in this case 13.04. So you end up on the upgrade treadmill, whether you want it or not.
I'm waiting for a month at least before installing any new Ubuntu version though. At release they tend to be a little unstable.
12.04 and earlier versions always had the option for full disk encryption with dm-crypt, but you had to use the alternate install CD with the curses installer. It wasn't complicated at all. All they did with later versions was to roll the option into the standard live CD installer.
Regarding bug fixes and the need to stay on the upgrade treadmill, it's much easier nowadays to stick with LTS versions since they implemented the LTS enablement stack (https://wiki.ubuntu.com/Kernel/LTSEnablementStack). Essentially it's the kernel and X.org of the current release backported to the LTS release, so you don't miss out on new hardware support while getting all the bug fixes and stability that come from the LTS.
That being said, however, I'm finding 12.04 to be extremely buggy when you're using Unity+Compiz.
I've got one box running 12.04 and one running 12.10. Unity+Compiz is definitely buggy for me on 12.04, but they managed to make it worse on 12.10.
I really cannot fathom what is going on at Canonical. I get that they want a more friendly UI, because that will create a better user experience for a broader set of users. I even use Unity, and like where they're going with it. But can't they see that creating a flaky, unreliable experience is not actually helping? And that they're undermining Linux's major strength, a reputation for reliability?
By all means, Canonical, keep innovating. But stop breaking shit along the way. If the goal is a better user experience, make sure you're actually delivering a better user experience before releasing.
Most people seem to say that 13.04 is smoother and more stable than 12.10. Canonical seem to have their ups and downs. I don't think desktop Linux has ever really had a great reputation for reliability, though.
Duh. That's obvious from the version numbers. Everyone knows that even dozens are supported 18 months and that prime number versions are only supported half of the time.
Ubuntu backports newer kernel versions and xorg packages[1]. I hope this will land in precise soon. That's good enough for me + the additional ppa here and there. I won't be upgrading to anything non-LTS on any non home machine again. It's not worth the pain.
I don't know if it is my browser, but to me I get the feeling the site is disabled, with the very darkend colors. It's almost as if a modal is showing, and the rest of the page is faded out - but I can't see no modal. Just my first impressions. But other than that: Really cool - going straight to the bookmarks!
