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Robbie
09-04-2008, 12:16 AM
Thread moved from community leader forum

I know this is off topic, but I wanted to show off my VERY early WIP 3d bits. I'm making an escapement mechanism with balance wheel animation in 3d...I had to show you guys because this is probably going to end up being my next avatar here ;)

If you don't know what an escapement is, its the mechanism in a watch that allows the spring to release itself in intervals that mark the watches movement. The clicking of the pallets on the escapement wheel gear is what makes the tick tock sound. Its really quite cool.

here's a link to an animation slowed down...mine will be close to actual time if I can pull it off...with every click being half a second...and one full swing (tick and tock) being a whole second. http://www.clockwatch.de/index.html?html/tec/hem/ank.htm

EARLY...I've modelled the important bits. Still gotta fine tune it...and when I get everything placed right, I'll make it artsy instead of just techy

delgondahntelius
09-04-2008, 02:15 AM
Artsy? Techy? ... either way it is cool... I wish I could do 3d stuff... but there is something I'll probably never be able to do ... 3d anything...

Very cool tho, can't wait to see the finished project...

And I thought an escapement was a piece of candy that you threw in your mouth after your significant other asks you a question you don't want to answer.... :D

ravells
09-04-2008, 06:14 AM
That's really beautifully rendered.

Robbie
09-04-2008, 08:32 AM
I just hope it works out in the end...thanks ;)

RPMiller
09-04-2008, 12:58 PM
Knowing a fair amount about 3D already I have to say that I never fail to be impressed by your work Robbie. I wish I had the time to really dip into the 3D tools I have so that I could try my hand at making models for Poser which is the only "toy" I seem to get time to play with other than PhotoShop and that is only once every couple weeks or so.

Robbie
09-04-2008, 02:30 PM
Eh, keep in mind I've been dicking around with 3d studio since R2.5 Thats a long time ago. Thanks for the praise though...I only wish I was better at it hehe.

Here's an update...I added the balance wheel weights, the ruby pin and all the parts to finalize the action. AND, I created the preliminary action animation. This is a full swing...2 seconds on a standard wind-up wristwatch.

ravells
09-04-2008, 02:32 PM
That is brilliant!!

Robbie
09-04-2008, 02:42 PM
I'm going to have to make the animation longer though because of the tines on the escapement gear...it resets...That may make the file size unmanageable.

delgondahntelius
09-04-2008, 02:44 PM
Excellent work..! ...

your file size might be unmanageable ... but at least you'd be in sync :D

RPMiller
09-04-2008, 03:02 PM
I can't wait to see the final version! If you save it as a flash animation wouldn't that cut down the size? I'm guessing our avatar image doesn't allow that though...

Robbie
09-04-2008, 03:36 PM
Here's a larger render of all the action bits...now all I have to do is streamline the action and make it artsy.

Robbie
09-15-2008, 05:06 PM
I'm stuck...anyone know anything about gear ratios???

I have a method in 3d studio to "wire" the rotation of one gear to the rotation of another gear to make a gear train...I can apply an expression to that wiring...for example, a gear that is "half" the size of its driver the ratio SHOULD be -1.5*Z_Rotation...but its not quite doing it right. (Negative to make it rotate the opposite direction)

Is gear ration related primarily to the number of teeth, circumference, or diameter of the gear...a website says that a 13 tooth gear linked to a 21 tooth gear should be a ratio of 1:1.62...which means the formula is -1.62*Z_Rotation, and it works sorta...but after a few rotations it starts getting off and the teeth no longer match up :(

RPMiller
09-15-2008, 05:12 PM
Are the gears fully meshed? In other words the teeth the same size as the space they go into. I believe that affects the ratio as well. I used to know the full formula and I believe circumference was part of it as well... Man that was like 2 decades ago...

EDIT: Correction. It is diameter. http://en.wikipedia.org/wiki/Gear_ratio

RobA
09-15-2008, 05:16 PM
Yep. With teeth, it is a straight ratio of the teeth. A 13 tooth gear would cause a 21 tooth gear to rotate at 13/21 or 1:1.615384615 which is probably why your 1.62*z sstarts getting off. That extra bit per clock cycle. Best to express it as a fraction in 3d studio if possible to get the max accuracy of the system.

-Rob A>

RobA
09-15-2008, 05:18 PM
Are the gears fully meshed? In other words the teeth the same size as the space they go into. I believe that affects the ratio as well. I used to know the full formula and I believe circumference was part of it as well... Man that was like 2 decades ago...

Doesn't mater if they are meshed fully or not. The circumference and tooth engagement don't affect speed, they only affect play, or slop in the geartrain (unless there is so much play you can skip teeth, of course...)

-Rob A>

RPMiller
09-15-2008, 05:28 PM
Apparently diameter factors in as well. Note edit above.

Robbie
09-15-2008, 07:15 PM
Well...its still not making sense...I did a formula: (-1*(1+(13/21)))*Z_Rotation for a 13 tooth gear and a 21 tooth gear...no dice.

Here's an example:

Gear1
ToothMin Radius: 5"
ToothMax Radius: 8"
Teeth: 21

Gear2
ToothMin Radius: 2"
ToothMax Radius: 5"
Teeth: 13

Am i dumb or something?

RPMiller
09-15-2008, 07:35 PM
Your math looks sound to me. I suspect that you are dealing with the accuracy of the modeling software though. Have you tried going out to more decimal places? If push comes to shove you could always change the number of teeth to something that gave you a clean whole number?

EDIT: Makes me think that this is where the watchmakers get their job security. They know some secret that insures they are 100% accurate, but the rest of us don't have that secret so couldn't achieve the result. Maybe they put in some sort of friction devices that slows one of the gears just enough to make it accurate or something. I don't know.

Robbie
09-15-2008, 07:46 PM
Even numbers don't even work...except 1 to 1...its weird.

RPMiller
09-15-2008, 08:20 PM
Ok, now that is weird. I wonder if the frame ratio has something to do with it? That is just weird. How about 1:2?

Robbie
09-15-2008, 08:25 PM
I just figured out the 1:2 as you wrote that...10 tooth to 20 tooth no matter what the scale always matches up at 1:2

The formula is -2*Z_Rotation for smaller gear having half the teeth...

so whats the proper math for say 13 to 21 then?

Its not (-1*(21/13))*Z_Rotation apparently

Edit: I just made a 11 and 21 gear ratio...calculated by hand as 1.9090909090~...
Punched in -1.9090909090*Z_Rotation, and it worked (but started to get off after about 30 rotations by a very small amount...thats still a result...

BUT...when I tried (-1*(21/11))*Z_Rotation I get bunk...so I think maybe my parentheses are off?

ravells
09-15-2008, 09:14 PM
I'm just a lawyer. I just know how to add a zero on the end of a bill, sometimes two.

RPMiller
09-16-2008, 12:23 AM
I just figured out the 1:2 as you wrote that...10 tooth to 20 tooth no matter what the scale always matches up at 1:2

The formula is -2*Z_Rotation for smaller gear having half the teeth...

so whats the proper math for say 13 to 21 then?

Its not (-1*(21/13))*Z_Rotation apparently

Edit: I just made a 11 and 21 gear ratio...calculated by hand as 1.9090909090~...
Punched in -1.9090909090*Z_Rotation, and it worked (but started to get off after about 30 rotations by a very small amount...thats still a result...

BUT...when I tried (-1*(21/11))*Z_Rotation I get bunk...so I think maybe my parentheses are off?
No, your parentheses are correct. I do the math as written and get -1.9090~*Z_rotation

Robbie
09-16-2008, 01:27 AM
Well, I've created more gears, and now that I know how to wire them together (and given that I'm probably going to be working primarily with 8 to 1) I've placed them where I want them to be for this device.

Even though it looks like a clock mechanism, which the mechanism is...its actually going to be a key. The small pinion gear on the top in the center is going to be the key to unlocking the Great Orrery and lead the PC's to the right places to begin to set the divine moons back to right.

Basically, the clockwork mechanism will be powered by the magic crystal, the crystal is attuned to the Divine Essence of the gods (moons) and pulses in time with the heartbeat of the Primary deity. Since thats currently not right, this key will allow the Orrery to position itself into the current "incorrect" position. Since once the moons started drifting out of alignment the sages and keepers of the Orrery shut it down since they could no longer track things.

Sorry about the stream of consciousness...I'm just planning my next few campaign sessions ;)

Whatcha think? (Other than the gears not all quite lining up yet, will work on that soon)

RPMiller
09-16-2008, 01:30 AM
Very nice and I like the back story. Very creative.

Robbie
09-16-2008, 12:37 PM
Its coming along...I've moved things around a bit...lined up the gears better so the teeth fit each other. The crystal is glowing now. I've given it a very early version of the housing. The big gear above the escape wheel is going to be the gear that interacts with the Orrery...though I'm thinking of making that the gear at the end of the chain (bottom of the balance wheel)...

Note also the jewel action can be better seen, and I added a balance spring.

Robbie
09-16-2008, 12:41 PM
Moving this thread to GD to get more feedback...Sorry guys ;)

torstan
09-16-2008, 01:17 PM
That's looking extremely cool, and I'd agree with RP - I love the backstory.

Good work.

Robbie
09-16-2008, 02:20 PM
Thanks! I'll probably be whipping out some more backstory as I get its functionality finalized...I'm thinking about changing the crystal to be part of the link up to the Orrery...so it would have a piece of crystal sticking out and a gear sticking out.

ravells
09-16-2008, 03:07 PM
That's looking really beautiful, Robbie!

Redrobes
09-16-2008, 08:05 PM
Really Awesome. The only thing I don't like is that you might lose your current avatar which I think is really cool !

someguy
09-16-2008, 08:24 PM
Very cool! That molten rock is the best I could manage.

Robbie
09-16-2008, 10:11 PM
Thanks! Yeah I may actually make this my new avatar when its done.

RobA
09-16-2008, 10:37 PM
The problem could be a integer division issue. Some software will return an integer if two integers are divided. Try 21.0/13.0 in the formula to see if that makes a difference.

-Rob A>

Robbie
09-16-2008, 10:43 PM
That was it!!! Nice find RobA!

Redrobes
09-17-2008, 07:06 AM
I was looking at your animated gif and its great but it might just look a touch easier on the eye if it had some inter frame motion blur. For me its looking like its lit with a strobe.

Another thing I am just merely curious about. The big wheel has those pins on the outside at irregular spacing. What do they do in a real clock ?

Robbie
09-17-2008, 09:22 AM
Yeah that animation was just to show the actual motion of the balance wheel and escapement...the final animation will be much more cinematic with specular bloom, lighting, and blur.

The pins are balance weights. They are irregularly spaced, but evenly spaced if you look at it in relation to the balance arm.

In a real watch/clock...the center wheel (which is the last big gear in the chain) is attached to the mainspring barrel (the spring that gets wound) which powers all the other gears in the train all the way to the escape wheel. The escape wheel basically pushes on the escape lever just enough to make the balance wheel keep its movement. The pins are adjustable by the watchmaker to account for slight imperfections in the manufacturing of the balance wheel...it has to be absolutely perfect, because a half a click (tick or a tock) inaccuracy out of every 1000 clicks could mean an inaccuracy of a couple of HOURS a day.

Do a search on youtube for balance wheel to see an example of the movement.

here's the standard geartrain on a clock.

Robbie
09-17-2008, 04:31 PM
I've decided to move th egear train out and make it longer, and go more for a "key" shape since it will technically be a key. I restarted the housing (right now just a disk at the balance wheel end) and added motion blur. Here you can see the balance wheel and the escape wheel slightly blurred because of its motion.

I have 600 frames of animation setup...thats 20 seconds of animation or ten full swings of the balance wheel. ALL the gears in the gear train are properly wired. and they work like a charm. Now I just gotta start building the housing and the method with which it will connect to the Orrery, and then render a movie.

Problem with rendering amovie is I'm currently at 1 minute per frame rendering time...thats 10 hours of rendering, give or take a few hours. Most of that time is due to the Motion Blur calculation. I tried rapid motion blur, but it crashes Max. Rapid motion blur would bring my full 600 frames render time down to 2 hours.

Here's a pic of it thus far though.

RPMiller
09-17-2008, 04:46 PM
Your players better buy the beverages for your next game session considering the amount of work you've put into this "prop". LOL

That is going to be very cool to see in action.

Robbie
09-17-2008, 04:54 PM
well...I found a workaround for the motion blur crash...I can still do motion blur and my renders at 320x240px are around 11 seconds.

Will post an .avi in about 2 hours or so.

Redrobes
09-17-2008, 09:24 PM
Just render more frames than you need by a factor of four and average 4 frames together... unless that IS the slow motion blur !

Robbie
09-17-2008, 09:55 PM
well, I dunno how it does it...its basically a mental ray rendering effect. What you're talking about is a post-processing effect. This actually lets me punch in shutter speed and f-stop and all that and it renders it accordingly.

Here's the animation...its a 15 meg .avi file. I'm probably not going to leave it up long, so see it now before I take it down.

http://www.cartographersguild.com/hosted/arankey.avi

Redrobes
09-17-2008, 10:03 PM
well, I dunno how it does it...its basically a mental ray rendering effect. What you're talking about is a post-processing effect. This actually lets me punch in shutter speed and f-stop and all that and it renders it accordingly.What your talking about (well with f-stops anyway) is depth of field rendering which does ray bundling via multiple passes through an aperture. Motion blur is basically an antialiasing thing where you oversample in the time domain and resample back to the correct frame rate again. Its exactly like rendering bigger frames and resampling down to the correct size for the spatial domain. When you resample it will do a blur as part of the process. The net result is that each of the frames of the moving wheel will be the average of 4 frames so that the moving bits are blurred but all the stationary bits are the same and thus not blurred. The more frames you use the better but if running a full speed anim of 30 fps say then the wheel should only move a little so 4 oversampled frames per real frame ought to be just enough to make it look like one seamless blur. Its always better to run anything at more res than you need, blend and resample back to the final. That goes for spatial X-Y res or time in frames res too.

I'll look at your anim now but I expect it will be superb :)

Robbie
09-17-2008, 10:18 PM
yeah f-stop is unrelated to the motion blur...but what I mentioned it for is that my rendering setup gives me full camera options...all the way down to photometric lighting even. I understand the concept though...and there was a quick rasterizer of the effect that makes it run faster that was crashing my program....the workaround eliminates the crashing part though, and still applies it.

Redrobes
09-17-2008, 10:21 PM
Ok, and your anim is very cool indeed :D

Robbie
09-17-2008, 10:37 PM
Thanks! I may scale it down to 50% keyframs...that way I get twice the movement in the same number of frames. It'll move faster though.
I also need to put in a hairspring for the balance wheel too...I deleted the old one, because it was "wrong"

Steel General
09-18-2008, 07:58 AM
This is really cool Arcana, nice work. I don't have the patience for the 3D modeling stuff.

Gamerprinter
09-18-2008, 10:56 AM
Very cool 3D, Arcana, not so much like my style of 3D - I'm very much more organic and loose about my 3D design. I could never design something like a machine or clock - too precise for my skills, but then you're an engineer, I'm an artist.

I love the 3D detailing - but as I said, it isn't something I could do, or even think of doing. Great job! Repped!

GP

RPMiller
09-18-2008, 12:57 PM
That is very smooth. I'm really curious now to see how the gem factors in and what the completed model will look like.

RobA
09-18-2008, 03:10 PM
I couldn't download. Tried straight from my server. Got 2 MB then stopped completely... I think my ISP is being a pain in the butt today...

-Rob A>

Sagenlicht
09-18-2008, 05:41 PM
well, I dunno how it does it...its basically a mental ray rendering effect. What you're talking about is a post-processing effect. This actually lets me punch in shutter speed and f-stop and all that and it renders it accordingly.

Here's the animation...its a 15 meg .avi file. I'm probably not going to leave it up long, so see it now before I take it down.

http://www.cartographersguild.com/hosted/arankey.avi

Thats really great Arcana, I am eager to read the fully story for that device :)

Redrobes
10-08-2008, 08:47 PM
Hey Arcana, did you catch this which was listed on boing boing today...

http://watchismo.blogspot.com/2008/10/1940-puja-thermo-pneumatic-clock.html

a pneumatic watch ? Its well bizarre and one for all you clockwork aficionados.

Robbie
10-11-2008, 11:58 AM
That is pretty cool! I've seen something like that before though I think.

I should probably update you guys on this thing...I rendered a quick render the other day to show the characters a general idea of what the device looked like, but its unfinished. I plan on doing some engraving and decorating overall...its missing a lot of that. Plus I'm going to tweak the gears so they're a bit more properly timed to the 20 hour days of my world.

Steel General
10-11-2008, 12:45 PM
Very nice...

I dub thee newly repped *Bonk*

Redrobes
10-11-2008, 05:32 PM
The motion blur is excellent :) Its all excellent, but the motion blur is particularly excellent ;)

Midgardsormr
02-19-2009, 01:46 AM
I ran across this impressive project while doing some research on orreries:
http://www.my-time-machines.net/astro_index.htm

For those not inclined to click through the page, this guy's building some insanely intricate clock, including an orrery and a lot of stuff that I, frankly, don't understand at all. According to his design notes, the mechanism will require a 130 pound weight to drive it all for eight days.

There are several videos of various parts in motion--it's truly amazing.