| Mech Rig.. |
 ScotlandDave |
I was inspired by ScreamingShadows1 to finally get round to doing a mech thingy. I`ve slowly but surely chipped away at it and i`ve now got a basic model that i want to do a test rig at this stage.
So what i`ve got is a typical robot-leg thing with like a hydraulic piston like the ones on diggers and stuff. I can rig the leg no probs but i want the leg to drive the piston (or vice versa). I`ve tried messing with various linking and sliding joints and stuff but i can`t get it to work.
Anybody know of any tutorials on this?
I`ll post something tomorrow i dont have the internet at home at the mo.
Old Portfolio Madness
read 1796 times
3/8/2007 4:38:53 AM (last edit: 3/8/2007 4:38:53 AM)
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| mrgrotey |
all you should need to do is have the two halves on the piston having a look at constraint looking at eachother, should be all you need to do so they stay together no matter the angle of the leg
read 1788 times
3/8/2007 4:53:06 AM (last edit: 3/8/2007 4:53:06 AM)
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| ScotlandDave |
Ok this is it so far. Basic i know.
Here`s the max file (max8). I wanted to see how it can be rigged before i build anymore to it but i`m stuck as far as getting those pistons working is concerned.
http://davidlamont.pwp.blueyonder.co.uk/files/mechyLEG.max
(david lamonts not me by the way different dave).
Have a good weekend and i`ll see yers on monday!
Old Portfolio Madness
read 1735 times
3/9/2007 10:21:45 AM (last edit: 3/9/2007 10:21:45 AM)
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| mrgrotey |
ive had a little go at what i think it should be like, any good? obviously its only a quick version and only a crappy rig but the principal is there and working
heres how its done, hopefully you can understand it
im guessing (i dont know mind as i cant open your file due to i only have max7) that the trouble you are having is because you are not letting the cylinder body rotate freely of the upper leg? its fixed solid? just a guess.
[edit] oh and the top two pivots would only one on your model obviously the cylinder body and the upper leg will both spin around the 'knee' nut
read 1723 times
3/9/2007 12:38:09 PM (last edit: 3/9/2007 12:39:55 PM)
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| ScotlandDave |
Thanks Mr Grote! That`s pretty much exactly what i want.. Took me a bit of messing about to realise i had to stick that dummy in for the lookat to work..
New problem! Is there any way to anchor that ankle at the very heel but also have it attached and rotating at the ankle joint (like dual pivots?).. It`d be useful so that when i animate it the heel stays but when it puts a foot down..
I thought about using a helper on the heel. And i`ve added a joint at the ankle that wasn`t there before.
How did u record ur viewport action like that?
Old Portfolio Madness
read 1673 times
3/12/2007 9:46:39 AM (last edit: 3/12/2007 9:46:39 AM)
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| ScotlandDave |
Anybody? Dual pivot type thing? is it possible or am i looking at this the wrong way..
Old Portfolio Madness
read 1632 times
3/14/2007 6:19:52 AM (last edit: 3/14/2007 6:19:52 AM)
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| mrgrotey |
if im getting you right you need the ankle to pivot at the back of the foot where it meets the gorund and at the ankle? if so you pretty much have what you need in the side view you posted except for one more dummy at the ankle,
i think all you you will need to do is link the foot object to the ankle dummy, then link the ankle dummy AND ankle IK chain to the heel dummy. now when you rotate the heel dummy the two ankle objects rotate taking the lower leg and foor with it and when you rotate the ankle dummy the foot rotates, havnt tried this yet so might need a bit of tweaking
read 1623 times
3/14/2007 7:19:52 AM (last edit: 3/14/2007 7:19:52 AM)
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| ScotlandDave |
Still not getting anywhere old chap. I don`t know if it`s even possible but i`m looking for a way to make it easier to ground the foot around the heel..
Thanks again for your help Grotey!
Old Portfolio Madness
read 1610 times
3/14/2007 10:17:43 AM (last edit: 3/14/2007 10:17:43 AM)
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| mrgrotey |
right this is what you want i believe, and it was a little more complex than i thought.
ive done the funky colour guide to the linking again, (red=link direction and blue = IK solver direction as before)
the words are jsut in place of dummy objects to show you clearly what they do, they can be any object you want though just as long as the pivot is in the same place.
i think the secret to this seup is creating a dummy at the ankle, linking that to the calf object and creating an IK solver to that instead of the foot objects.
just always use the hell control to move the foot/bend the leg
oh and heres the subtree to further expalin the linking order
[edit] there is going to be a problem when you attach the piston body part to the thigh. at the moment the look at has to look at the base of the piston shaft from the center of the piston body, and therefore the pivot point of the piston head needs to be in the center. when you move the pivot point of the body to the 'knee' joint the lookat wont work right as it will be referencing form the joint rather than the center of the body. hmm tricky one there
read 1598 times
3/14/2007 1:33:49 PM (last edit: 3/14/2007 1:45:30 PM)
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| vishesh |
mrgrotey ...... Wow !! thats a great work you have done.
if you have some time, can u make a tutorial regarding the mechanical animation or may be just make a tutorial regarding how to make this Rig.
there are very few tuts on net abt mechanical Rig, kindly correct me if i am wrong.
i am quite new to IK, bones etc.... so i can't really understand how u did this :P
Cheers !!!
"Passion is the flame that burns forever."
read 1585 times
3/14/2007 3:07:02 PM (last edit: 3/14/2007 3:07:02 PM)
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| mrgrotey |
vish: cheers mate,
basically just put all the pieces in place as in the picture making sure the pivot points are in the correct place for where they need to spin around then link it all up as shown byt the red arrows, and then add the HI solver in from the thigh object to the ankle dummy object.
thats all there is to it really, the difficulty is thinking it out in the first place to get it to work as somethings create dependancy loops and something rotate with something and not with others.
having a go is your best bet here.
all you need to know is that the objects need to be linked before doing the IK chain and the joints should be partly bent in the direction you want them to bend in after the IK has been applied, other wise, if the joint is perfectly straight, max just guesses the direction and sometimes gets it wrong. Other than this its pretty straight forward to copy.
read 1575 times
3/14/2007 4:34:58 PM (last edit: 3/14/2007 4:34:58 PM)
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| vishesh |
thanks for the info abt IK, hierarchies .... mrgrotey ;)
i am gonna start playing with the IK, hierarchies now .... if i got stuck somewhere, i will let u guys know.
Cheers !!!
"Passion is the flame that burns forever."
read 1556 times
3/14/2007 11:32:51 PM (last edit: 3/14/2007 11:32:51 PM)
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| ScotlandDave |
Thanks again Grotey yer a diamond geezer! I actually figured a method last night which is slightly different from yours so i`ll post it up here for future reference..
The dummy linked to the toe is basically just an end for the IK chain. The rectangle helper is pivoted at the heel. So with these two i can have him doing tip-toes and also grounding onto his heels (which should hopefully be much more fun/easier to animate).
I`ll post up a bit of animation once i do a bit of a test walk-cycle. And once again MR GROTEY thanks for all your help if everybody was so good the world would be a fairer place.
[edit] how DID u record your viewport?
Old Portfolio Madness
read 1541 times
3/15/2007 4:37:04 AM (last edit: 3/15/2007 4:39:51 AM)
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| mrgrotey |
oh ok fair enough :) you are letting the toe part rotate as well arent you? could look very stiff animation other wise with a solid foot
read 1536 times
3/15/2007 4:40:40 AM (last edit: 3/15/2007 4:40:40 AM)
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| ScotlandDave |
DagNammit! You`re right. I think if i stick in a third IK chain between the heel and the toe.. not sure. I`m at work so when i get home i`ll try it and post up tomorrow..
Old Portfolio Madness
read 1525 times
3/15/2007 6:02:21 AM (last edit: 3/15/2007 6:02:21 AM)
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