View Full Version : Setting up to animate small moving parts

assistant pimp
08 August 2005, 07:14 PM
This is kind of spin off of my animating a robot arm post. I am planning out my animation with sketches at the moment. My question is....Lets say I have a robot arm that is on a spindle or a pivot. Now when it comes to animating this, is it important how I layer the objects? or should I make like selection sets? Like one Main object will move (lets say the entire arm), but while that arm is moving there may be a pulley turning or another object pushing to make the motion possible. I guess I am confusing myself because I really dont know where to begin. I want to start modelling, but fear I will have to start all over due to the fact I grouped or layered the objects wrong or what have you.

A good example is imagine a train wheel. So many other parts moving to make the motion of the wheel possible. Maybe if there is a tut on that, that could get me started.

help pleez.

08 August 2005, 10:29 PM
Even if you model it all wrong in terms of layers. It's all easily fixable so don't worry about that.
In fact, you could either use separate layers for each part, either modelled in place by moving the pivot in layout.. or moving the parts so that the pivot lies at 0,0,0
Or you could put it all on 1 layer, and use weightmaps and bones to animate the parts separately.

As for animating it, you can use a variety of different methods to automate motions attached to the rotation of one part. Cyclist is very good for complex motions, follower is good for simpler channel following. Ik and targeting also will do for some piston types.

With IK, you could have a Steam train piston setup. IK is good to make things point at things and to make a joint bend automatically whilst the end points at a target.

Cyclist will do practically anything as complex as you want.. You could have an animated monkey climbing up and down a tree when the arm bends up and down if you so desired. I recommend reading up on it. It's one of the most underused yet powerful tool in LW.

08 August 2005, 01:00 AM
for pistons you can also make two bones. One for the fix part and one for the jack. Each part has its own weight map. Each bone is targeted to the other one, that works great. Look at the attached scene to see a very simple bone set up that works fine for pistons.

assistant pimp
08 August 2005, 01:25 AM
Many thanks guys. I am going to read up on these terms. And try some sample things.

08 August 2005, 11:08 AM
I did the same setup for gears, bones + weight maps + followers. The ratio between the rotation speed is equal to the ration between gear radius.


assistant pimp
08 August 2005, 10:08 PM
thanks telamon.....great stuff.

CGTalk Moderation
08 August 2005, 10:09 PM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.