oakchas

Actually GA, I'm thinking of making a bit of a "story" out of it.... from magazine article, to CAD drawings, to primitive CAD animation, replaced by the model in wireframe and then a transition to the working model, with some transparency to begin.. finishing off with a blue screen composite of it "in situ" on a coffee table... That's the dream anyway... we'll see how reality works out.

Going off the original drawings. The piston is only ~1" in diameter. The cylinder is ~ 2 1/4" long... The Connecting rod (piston arm) is 5/16" square at the ends for a 3/32nd" piston pin. Originally designed to be made from a 1" ID plumbing pipe, pipe cap, and various scraps. This (particular) candle engine may never have been made... there's some speculation on that as vacuum engines are notoriously finicky to operate, though when they do, they are fascinating.

'kay, so here's the piston, cam and flywheels. yet to do are the cylinder and the stand. I'm trying to work (at this point) without using decals or materials. they will be added later. It's based on an old Popular Mechanics article where a candle is used to "power" this engine. The flame from the candle fills the cylinder, then a valve closes off the flame. This creates a vacuum in the cylinder which is the "power stroke" which opens the valve and the flame is then readmitted to the cylinder. and so on. I've got to get the flywheels and piston to look as though they were machined stainless steel. This is just a start, and I need to study up on reflectivity and specularity to try to make this more realistic looking. But I have to say I'm terribly impressed with what A:M can do to make the materials without using materials or maps yet... I'ts pretty cool in just it's base surface properties mode. my_piston.mov

Bingo! Of course! I agree Rodger... The brute force method works and in the time I try to look at relationships I could have done the whole thing by hand! Sometimes trying to understand all the features is unnecessary if there is a work around (especially one that works as well or better). While I am not doing anything as complex as a steam loco, I can easily visualize what has to occur for this mechanical model to function. You do have access to the tute as it is online as well as on the DVD the link is above. Now the remaining question is... in order to have the action loop without hesitation at TDC... I can eliminate the last frame (in the ACTION only) and repeat the action in the chor (as there are other actions occuring over a time where the piston cycles several revolutions)... yes? Is that correct? Thanks for your input rodger, it really helps to not think I HAVE to work all the bells and whistles, when all one needs to do (to get from point a to point b ) is sit in the drivers seat and drive the darned car... Stereo and cruise control are nice to have but you don't NEED them.

It's on the V14 extras DVD but that one is incomplete... here's the link to the original: piston tute Now I'm going back to the topic because I noticed that Johnl3d did a project with relationships.

Whoa! So, I'm in the midst of doing the piston tutorial. Everything is going along swimmingly. The tutorial works. I can make a piston go up and down while the crankshaft turns. Exactly as advertised. Well, except for those inbetween keyframes where you have to make more keyframes to get the "shaft" bone to line up correctly with the crankshaft pin... Then it's "close enough," but it really isn't. Somewhere (early on) in the tute is mentioned the fact that we're going to "brute force" this animation without relationships, etc. Great, I can handle that, as long as it works. But, it really doesn't. Well, not accurately enough. It will look fine as it's moving, but somebody's gonna step through it and see that the shaft (con rod) is not actually lined up with the center of the crank pin. So great, I'll try a relationship. Look that up in the tech ref... I get lots of references to expressions... So, I look at the recent discussion on expressions... man they do a lot, but I got scared in there... 'as easy as calculus" Colin said... Well, Chinese would be easier for me (maybe). Okay, so back to the tech ref. Bones... 100 instances of... you say "oiler", I say "you ler" and how great that is at working the constraints of a bone in a mechanical model but not so hot at human stuff... okay bingo, that's what I want.. this is a piston; mechanical as can be. But I want the center of the con rod (shaft) hole to always center on the crank pin. I can do that by making each frame a key frame. But is there another way? Easier? Aren't alot of keyframes "bad"(unnecessary)?" Anyway all that math and calculus stuff scared me back here to newbie status... Here are 2 questions as a result of the piston tutorial. 1. is there a way to make the con rod hole always line up with the crank pin without all those keyframes? 2. The action in the piston tute is 20 frames long but only needs to be animated for 19 to make one full revolution (then loop). If I want to animate over alonger period... how do I get the hitch out of the TDC position of the piston...? Eliminate a keyframe (#20)? You can explain here or just point me to something in TAO A:M or a tute I can follow to understand. I'm feeling intimidated over something simple. (which is making me feel very old). Crochety old technophobe....

HMMMM, coulda sworn... well, I thought I saw it in a tute. mustve been into a chor rather than a model... but I thought piston tute showd a drag and drop of the lug about half way thru... no time to look now... I can get it there, that's all that matters.

The libraries are on the program CD (OZ), not on the HDD I can't drag and drop a primitive from the library panel to the modeling window. I can't drag and drop a primitive from the Library panel to the PWS model that is open, or to any other (new) slot in the PWS. I CAN import a primitive to a new model window. But drag and drop would be easier. What am I doing wrong? Thanks,

Larry, Welcome back aboard! I was in somewhat the same positon as you a couple of years back. I had an older (much older)version of A:M and really needed to go through at least some of the tutorials in the book The Art of Animation:Master (Tao A:M), which you should have gotten with your upgrade. There are so many features in A:M that have changed and improved over the years that I really needed the refresher. I also have had some difficulty converting my mind from polygons in CAD to splines in Hash. There will be a learning (or in our case, re-learning) curve. But given the organic (literally) nature of your cute characters, I think you were absolutely correct in choosing this program for your upcoming interactive DVD. You may have gotten the Technical Reference book as well. And it is a bit dry and not nearly as "digestible" as the Tao A:M If you didn't get Tao A:M perhaps you could call the folks at Hash, and ask for it. Or, at least look through the tutorial section of the forums and Hash's mian web site. Here's the link to the video tutes: video tutorials Best of luck to you in your getting your characters on the screen... It can be done, very well, with your A:M. And, most everybody here is willing to help. Sincerely,

The porthole trick will do the job. Fantastic! Sometimes I get so cautious about adding more control points and splines to a model, I forget that I can do that (add more) to make something happen... The solution is pretty obvious when you think about it. Elegant solutions usually are pretty simple. Thanks again!

Thanks All! Ken, yep, that takes care of the sphere. And similarly, it's reasonably easy to do a cup or pipe cap with a hole through the center. But, how would one do a "wrist pin" through the side of an upright cylinder..? I can't look at zips here at work, so I'll look at Paul's tute tomorrow.. thanks. Charlie Added this pic... more like the one on the left.

Search was futile. I know, I'm thinking in CAD instead of A:M (for shame)... But is there a way to put a "real" hole in a sphere or a (perpendicular to the length of the) cylinder? Probably not an easy thing. Of course, beveling such a hole in a CAD program would be no joy either. As an example, the wrist pin hole in a piston. I realise that A:M lets me simply stick the pin through the cylinder at right angles. But no beveling of the hole is possible except with a bump or displacement map. And that really doesn't leave me with a hole, just a rod through a sphere or a cylinder. Must learn to think A:M again. (Looks like, not is, nor does it have to be. It only needs to look like it is). Thanks for any ideas. Charlie

Nope, just the fact that the file was missing.

nah, Ken it's camtasia. And should play through SWF which I have installed... I'm currenly downloading the original from gene's post. Just wanted to avoid DL'ing a 46 MB zip. Even with DSL (slow DSL) it's a lonnnng DL. Thanks though, I'll let you know if the DL version works. Charlie Download version works... apparently, the file PistonTutorial.swf is missing from the extras DVD.

The tute won't play, Bruce. I can open the project and decipher... the tute might help me decipher better. I've got enough mental horsepower to figure it out, but with age comes a certain desire for efficiency, IE:not excercising all the brain cells at once so as to not require a nap mid afternoon. So, bottom line: All I really wanna do is play the tute, and it won't "go" Charlie

The extras DVD: Tutorials Folder Piston Folder Piston.zip I have extracted the Piston.zip file to it's own folder on my hard drive. I have opened Piston Tutorial/Piston Tutorial.html I get the active x popup on my browser page, I click to allow (use this control) I get the "play bar" for the tute... nothing more. I need to make a working piston. I'm sad. I can't see how to do it. I want a make piston button. Uh... Help? Charlie

Missed Martin's comment, oh well... Probably misinterpreted. John, good stuff! Glad someone can make a living with A:M and do big things, without becoming "too big" for the community. Thanks for sharing. Charlie

Kinda reminds me of the music video from Money for Nothin' Enjoy Dire Straits!

Dennis, Looks good... I too would like a comparison shot... but otherwise, his jeans look a bit like teen girls wear nowadays... too short for a guy his (my?) age between the crotch and the belt. not that he should pull it up over his belly.. just needs more length between the beltline and the crotch inseam. (I know, I said crotch..)

Stian, I've already said all that I can say. This is positively awesome. The head on view (front) has no DOF or perspective that I can see. It is so (much) head on that it looks like a round boat with no pointy parts (no bow). On the other hand.. the modeling is so perfect, I don't give a rip. It's just scary good. Sigh. Less time commenting on stians work, more work on the batmobile.

Stian! It's AWESOME! There's no more to say. I do have a question. Would all the portholes always be open when not in combat? My only comment is this, and really, it's premature. It still looks like a model to me... (and that's why I say the comment is premature, I know you're not done texturing yet.) I have one more question. Why hasn't your sig line changed? You do fantastic work, you do it quickly. I honestly don't understand. You should have a job by now if not the career. Thank you for sharing your progress on this formidable ship and project with us... It could certainly be an illustration in a school text, or naval history book.

T Dogg, Looking very good! Glad to see you have had much help in my absence. Rodger's right, of course, about the lure of low patch counts.. that's my problem with the hood.. I need to bite the bullet and get back at it... it's gonna be a tough summer for me .. .many others get vacation now, and I have to work a lot of 12 hour days to cover for them... Keep going! you are doing really well.

at full rez I see no jaggies... Looks great!

looks like a mic. except the wire mesh looks painted on... is there a wire mesh? dunno if a bump map would work, splinage would be Heavvvvy, so I don't think that's the answer either. Otherwise. looks quite realistic.

Thanks Tom, T Dogg is doin' most of the work here .. I'm just "Doggin' him" to get it done... Though I am also working on mine, just more slowly.