Tuesday, October 30, 2007

more on intermittent motion

I was thinking about how to reproduce intermittent motion. It is not as straightforward as the little animation I linked to two posts ago because any time I give something a push, it is going to continue to rotate. There just isn't enough friction to stop it. I am thinking I will need some kind of break that allows a gear to start and stop. First I thought of a couple of ways to do it some disks with slots cut out of them to allow the gear to continue to rotate only when the disks rotate into the proper position. Then I thought about watches and the escape movement in them. Then I thought a lot about how that escape movement looks a lot like movement 114. <- in that link I dream about a processor farm and whine about only having a half gig of ram. The ram thing is just a coincidence.

The above picture is like a double escape. I plan on placing a mutilated pinion in the center, perhaps a wider center, and two other gears in between the forks of the rack. The hope is the rack slides back and forward causing the gears to start and stop rotating.

That's the plan thus far.


Monday, October 29, 2007

Intermittent Motion

It's going to be tricky!

starting the simulation

Here is the cam system in NE1. I'm starting the simulation in a few minutes, so we'll see how it goes in a couple days. Once this system is perfected (or close enough to move on), we'll have two good ways to turn rotary motion into linear motion. However these cam systems don't seem to be very efficient from an atom use point of view; it takes a lot of atoms to build these cams, and the linear motion isn't too far. But then again that is a problem I happen to encounter because I basically have to build them by hand with a computer that only, let me type that again for emphasis, only has a half gig of ram. Just thinking that these cam are basically homogeneous opposed to the pinions that contain very precisely placed oxygen atoms, they strike me as being easier to build in the lab.

Looking on, I am starting to get excited about building a diamondoid system that displays intermittent motion. In fact now I am thinking I should not have started the simulation ( I just did) on my build computer. I think I'll stop it and restart it on my main simulation computer so I can work on this new system.


Saturday, October 27, 2007

testing the cam

I am a little concerned that this cam may turn out to be as rigid as a cooked noodle, so I think I should test it out. The above picture is a rough throw together of how I plan to do it, just see how it pushes up some cnts. I am not ready to simulate it yet. I never minimized the energy on the cam itself, and at nearly 15,000 atoms it is going to take a while.


Wednesday, October 24, 2007

a couple excuses

I should be getting back into things here soon. Not to make excuses, but my math prof has insisted on an exam a week, just about. I am ok with that because a bunch of small tests are better than a few large ones if you play the odds. Also I have been spending some time (hard time) learning the ins and outs of some very large DNA structures. After a shaky start, I venture to say it's in the bag from here on out, but for a while I felt sort of like a boxer that, literally, kept jabbing with a left when he should be swinging with a right. Here is where things stand:

1. It has been suggested that maybe a boron nitride slab may be stiffer than a diamond one. I have not harassed anyone in the know about these things (initials are DA) for a while, so I may drop him a line, or just test it out. Double thanks for the suggestion though, "Guy".

2. I will spare you my quixotic quest to nail movement 114. However if I exclude quixotic quests, this blog would be thinned out considerably.


Tuesday, October 16, 2007

next version of the diamond system-simulation

Sorry-Qutemol animations just take too long with these large files. The timing is still a little off, but I'm not going to spend another five days to prefect that. Now I need to reread back through this blog and see what I was trying to do before going on this tangent. However there is an unbelievable temptation to settle the score with movement 114; that rack won't know what diamond pinion hit it.

Thursday, October 11, 2007

what is it- round 1

First person to call it in an email gets a congratulatory e-card!

Also, no dice on the Falcon Northwest sponsorship, but at least they write back. That's ok because it still leaves Cray in the hunt.

We are about 27% done on the next diamond system simulation.

Wednesday, October 10, 2007

adding some SiC gaurds

I guess we'll know the effectiveness in a few days. These are to prevent anyone from pinching their fingers as much as they are to align the rack. I wonder if Falcon Northwest is looking to sponsor some high power molecular dynamics simulations?

missed it by that much

The rack does head back after being extended, but now the timing is a little off. Actually it is off by what appears to be the exact amount I moved the diamond target & gear back. Now I will spin moving them back as a demonstration of how not to run good experiments: only change one variable between iterations. You're welcome for that lesson. I bet if you were watching me watch the first run through on the sim, you would see my face scrunch up in direct relation to how far the rack moves in the +x direction. Also you can probably tell it is time to implement one of those three ways to stabilize the rack, as anticipated.


Monday, October 8, 2007

DNA octahedron array while you're waiting

The next simulation of the diamond system won't be done for another couple days, so here is something I am working on. It is still a little rough. It is an array of DNA octahedrons. The array is being used to position silsesquioxanes. If I knew how to pronounce that, I would give you a phonetic spelling. H/T to Tee for them though; perhaps he will read this and leave a guide to pronunciation in a comment or email. I believe a similar use is what originally inspired Ned Seeman in get into DNA nanotechnology way back when.

Addendum: you can read a little more on the silsesquioxanes here

Friday, October 5, 2007

and the diamonds said smooch

That's about half of it; now to bring her on home. Oh yeah, I didn't extend the rack (yet), but I believe there are any number of things (3) to stabilize it if I need to.


and the rack went weeeeeee!

Alright no big deal and totally my fault. Instead of extending the rack I thought I would just place the pinions on the end. Don't place the pinions on the end. At least I have a time duration for the diamond chunk to rotate into position. I will double the length of the rack and shift the pinions back. Also I am thinking of adding another set of pinions, one set moving the rack in the +X direction and one that will move it in the -X instead of one pinion in each direction.

Wednesday, October 3, 2007

A plan b post with some DNA

Around 5:45 am this morning the electricity flickered and then settled around 40V for a few hours (I checked with my trusty old Fluke 23 series multitester. I always questioned the marketing wisdom of naming precision/high end testing equipment "Fluke") causing the computers to turn off. My initial test on the diamond system has to be restarted. A while back I asked if it was alright to post on a new reduced DNA model that is currently being implemented in NE1: PAM3. This model represents the DNA strand with three pseudo-atoms opposed to PAM5's five. It makes for a much more visually streamlined model.

Tuesday, October 2, 2007

moving into systems

I know I am supposed to be building a motion controller, but this is the first steps, and pretty neat on its own. I will use two mutilated pinions to drive the diamond beam in a reciprocating manner and try to time it to kiss the diamond chunk on the large gear. However I have yet to test either of these two steps and have absolutely no experience with timed motions, taking more of a let-her-rip approach in the past. I still need to work out the numbers, not tonight though.

Also, I am getting some errors with my mail service. If you were expecting an email from me and didn't get it, let me know.


diamond rack and pinion

It is the crazy auto adjusting of qutemol that gives the illusion that the pinion is just turning up the rack. I thought I compensated for it by zooming out a little, but I guess not. If anyone really wants it, I will make a NE1/POV-ray animation that shows the rack turning the pinion. However you can see there is a nice fit between the teeth for pretty precise control. Also everything is at the same scale as the rest of the diamond parts I have. The rack started out as a shaft section on my diamond cam.

The gear moiety allows for a large range of diameters too.


Monday, October 1, 2007

more on the motion controller project

This polycyclic aromatic chain is the stiffest/thinest thing I have come up with yet. Perhaps it could be made to work. However I am starting to consider something else. Take a look at this picture:

I am starting to get a nice little library of diamond-type stuff that is pretty much scaled to work with each other. So I am thinking of rebuilding the Fine Motion Controller at a scale where I can use these cams, gears, rods, etc. In fact I am thinking of making all sorts of similar scaled parts, out of diamond wherever I can, then I will have all these ready made parts that can work with each other. Oh yeah, of course I would offer to add them to the NE1 part library too, then you could have a set as well.