Those are really cool to look at. I kept trying to click them to learn more, I wish some of them were mini blog posts to give a little bit of grounding.
It sent me back in time, very nostalgic. I even took a few minutes to sit and enjoy the moment and remember what it was like to explore the internet on a pixelated CRT in the 90s.
Yours. I can't explain your frustration then, or why the author's intent escaped you. If you use Firefox there's a little reader-mode icon in the address bar you may find convenient.
Thank you! I'm working on a robot with a very expensive slip ring, and need to send high fidelity data through it with shielding. I had no idea this was possible this will make things so much easier!
I found a related video you might find interesting.
I'm currently studying group theory and SO3 rotations (quaternions & matrix groups) and I'm also curious about the connection. I still have a lot to learn but I wouldn't be surprised if the reset rotation is unique, if we abstract away variation.
As meindnoch points out, the connection needs to loop over the rotating object. That is no problem if the only affect of the rotation that interests you is the centrifugal force.
When you give plasma (not whole blood) the nurses use a centrifuge machine that seems impossible: one tube goes from you to it (carrying whole blood), another tube goes from it back to you (carrying plasma depleted blood). The mechanism of Dale. A. Adams keeps the tubes from twisting. Search “antitwister mechanism patent” for a drawing of the mechanism. As for the principle behind the mechanism, see http://Antitwister.ariwatch.com for a PC program where you can adjust every variable imaginable.
What a fascinating project. It looks a real labor of love, and I wish I understood it more deeply. I've been making my own visualization sandboxes like this to explore configuration spaces and groups - but for much simpler, more intuitive physical systems.
I went down a few rabbit holes on the site - is this program also written in Basic?
Yes, specifically the PowerBasic console compiler version 4 (later versions don’t do animation nearly as well). The PowerBasic compilers are no longer being sold and the company appears to be defunct. Anyway, you can do a lot with a good BASIC compiler.
This is important. The mechanism doesn't really work the way you want most of the time. I occasionally see a claim that you can power a carousel with this method, but it doesn't work. You would have to have the cable go out and around the carousel structure, and then into the top. And the cable would still move relative to the ground and the carousel.
You could, in principle, have a totally internal system, but with arms that grab and release the cable at intervals so that the looped portion can pass by them. You could arrange the timing so that electrical contact is never lost. But you are still making/breaking contact and it starts to lose some apparent advantages compared to a slip ring.
That's not to say it isn't still useful for some purposes, like maybe a radio antenna that isn't too impacted by a cable moving in front on occasion. But it doesn't eliminate all uses for a slip ring.
I can't go into detail, but that's essentially my use case. I have a geodesic dome with a cable running up externally, and would like to run it through a hollow shaft coming in through the top which rotates like a carousel. I'm fairly certain this is precisely what I need.
Always happy to share! I came across this while planning a 3D scanning (photogrammetry) rig. Perhaps you'll be the one to figure out gravity can be modelled as a rotation around an axis in a fourth dimension, wrapping clingy spacetime around itself? ;) I'm not clever enough for that.
I've been using Magit for years, and have never noticed any bugs.
The interface is unique and takes a lot of getting used to. I did need to leverage my extensive experience with Git and Emacs to understand unexpected behaviour but the fault always lay with me.
Given the implications of bugs in such a critical part of a developer's workflow, can you be more specific?
Mainly random lisp errors being thrown in certain cases, likely just unimplemented functionality, I didn't record them since there are so many. I probably see one every other day but usually it's somewhat outside of the normal operation of magit. It still feels like a bug though, and very likely is.
I mean, magit is not some perfect piece of software. Of course it has bugs, I just hit them quite a lot. The slowness is more annoying though. Sometimes it takes seconds to open magit after hitting C-x g
I've also had magit get stuck in a 100% CPU usage loop a couple times
That sounds frustrating! It hasn't been my experience at all.
I'm an enthusiast when it comes to [Vanilla] Emacs. I enjoy customizing my editor, jumping into the Lisp when I find an error, and contributing - though my own config is usually the problem.
This sounds like an opportunity to improve the day-to-day for developers!
Please report any verified bugs to Github. There are only 12 open issues, most of them enhancement requests. The maintainers are celebrated in the community for their diligence and attentive engagement, and I'm sure they'd love to help.
Loved the article, and also the shoutout to Strang's lectures.
I agree with the order, the Gaussian should come later I almost closed the article - glad I kept scrolling out of curiosity.
Also I felt like I had been primed to think about nickles and pennies as variables rather than coefficients due to the color scheme, so when I got to the food section I naturally expected to see the column picture first.
When I encountered the carb/protein matrix instead, I perceived it in the form:
[A][x], where the x is [milk bread].T
so I naturally perceived the matrix as a transformation and saw the food items as variables about to be "passed through" the matrix.
But another part of my brain immediately recognized the matrix as a dataset of feature vectors, [[milk].T [bread].T], yearning for y = f(W @ x).
I was never able to resolve this tension in my mind...
I love this idea. I remember giving a live demonstration of a configuration management tool (SaltStack circa 2012) and some unknown networking conflict between my Virtual Machines and the local wifi subnet caused my commands to timeout. I was too junior to resolve it live and was left with boring slides explaining what ought to be happening.
Luckily it was a small group of devs and not a large venue. Still embarrassing...
I've been curious about knitting & crochet from a programming / robotics / simulation perspective for a while, but deferred it to cut my teeth on simpler problems. Those industrial robots seems to be knitting, not crocheting. They use the term "crochet knitting" as a sales tactic.
This short video is annoying but informative: [1]
The closest I've seen to actual robotic crochet is [2].
Which is exciting and close - but it's hard to overstate its limitations. I took the challenge in that short video seriously and spent 10-20 hours learning basic crochet. It became very clear that replicating my simple test patterns would require vision, planning and modeling capabilities beyond anything I've seen in SOTA surgical robots.
What I find interesting about the post (Knotty) is buried here [3] - apparently it's possible to ditch the grid and create an intuitive representation of the final knit pattern. I suspect that may be doable using traditional algorithms.
