can you limit x y z motion?

[fabmedia]

I'm curious... I looked through the LW 7.5 manual, but I cannot find any information on limiting the distance and motion in the x y z axis. Does anybody have any information on this. I'm not talking the rotation, but the straight distance.

I have an IK chain that I want to limit the goal object to only a certain distance. This would make my life a lot easier when it comes to animating. I would like to turn or limit the x axis motion/distance to 0, Y to ? and Z to ?. As it is, the angle limits on the IK chain has been limited to the pitch. This is for landing gear.

Arlen

[NeilNafus]

An expression on the object you want limited would work. You would add a null for a reference for the expression, essentially you would just tell it, if its x pos is less than A then do nothing and if its x pos is greater than A to keep value A as the position, where A is the max x value. Something along those lines should work. I hope that will help get you pointed in the right direction.

-Neil Nafus

[fabmedia]

well... I start with an expression and now I want to control the expression with a null, but it's not working. I've animated my base item, and linked another item to mirror that animation, and then applied cycler to the initial animated object.

The inital animation takes place over the 30 frames and the controlling null over 90 of which the first 30 opens, 30-60 holds the motion, then 60-90 returns the controlling null to it's original position.

Now here's where it gets ugly. After frame 30 the doors "snap" back to thier original position, after 60 only the one side closes after it snaps out to the open position.

And to boot, the doors aren't even in thier original position. Damned if I know what's going on...

Please help. I'm in a desperate need. (Seems all of this stuff is)

here's the link... http://216.232.120.141/movies/spacejet.mov (quicktime)

and then http://216.232.120.141/movies/spacejet2.mov

Not sure what I'm doing right or wrong, but help is definitely needed.

Arlen

[fabmedia]

Okay... here's another... http://216.232.120.141/movies/spacejet3.mov

I've managed to fix it for the most part except the jerk at the very end of the cycle which of course I have no hope in hell in figuring out. SO for those who are stumpped this is for you.

To use Cycler with objects that are linked using Channel Follower (children of the parent animation) you need to tell the child objects that the animation is longer than the animation sequence of the parent object.

In this instance, the doors opening is a 30 frame animation. The mirrored door (the child object linked with Channel Follower) needs to be told that the animation is longer. So the animation end needs to be substantially longer than the parent animation. So in my case, the jet will open the landing gear doors and land. then the animation will take place for an additional 20 seconds (one continuous shot) and then take off where the landing gear doors need to close. So this tells me that the child objects animation end frame must be at least 700 frames at 30fps. Otherwise it'll screw up and look like the previous two links.

Damn well took me all day to figure this out.

Cheers!
Arlen

[dbolto]

Just in case you hadn't ran across this. This link might help:

http://www.sector3.com.au/channeLimiter.asp

Graphixkid2000

www.dbolto.com

[SplineGod]

Originally posted by fabmedia
I'm curious... I looked through the LW 7.5 manual, but I cannot find any information on limiting the distance and motion in the x y z axis. Does anybody have any information on this. I'm not talking the rotation, but the straight distance.

I have an IK chain that I want to limit the goal object to only a certain distance. This would make my life a lot easier when it comes to animating. I would like to turn or limit the x axis motion/distance to 0, Y to ? and Z to ?. As it is, the angle limits on the IK chain has been limited to the pitch. This is for landing gear.

Arlen
You could do it with expressions. Myself, I wouldnt use IK to control the landing gear. Just manually animate the gear in the open position and use cyclist to control the assembly. Its much easier IMO.

[fabmedia]

Okay, so I managed to use Channel Follower and cycler to open and close the bay doors. You can see it here.... http://216.232.120.141/movies/spacejet3.mov

Now I would really like to make my life easier by animating the controlling Null with the morph mixer. I have problems with using sliders on items that other people create, as in I can't setlect them and actually slide them about. So any suggestions?

Arlen

PS thanks for all the help by the way.

[SplineGod]

Originally posted by fabmedia
Okay, so I managed to use Channel Follower and cycler to open and close the bay doors. You can see it here.... http://216.232.120.141/movies/spacejet3.mov

Now I would really like to make my life easier by animating the controlling Null with the morph mixer. I have problems with using sliders on items that other people create, as in I can't setlect them and actually slide them about. So any suggestions?

Arlen

PS thanks for all the help by the way.
Actually I would use Cyclist in the motion panel.

[fabmedia]

I am using Cyclist on the Control null (animate the control null to open the doors). But I want to use morph mixer to control the movement of the control null.

It sounds confusing...

A

[SplineGod]

Originally posted by fabmedia
I am using Cyclist on the Control null (animate the control null to open the doors). But I want to use morph mixer to control the movement of the control null.

It sounds confusing...

A
Why do you want to use a morph control panel to move a null wh en you can simply just move the null?

[Lamont]

Originally posted by SplineGod
Why do you want to use a morph control panel to move a null wh en you can simply just move the null? It's cooler that way yo'!

Just slap Item Shape on the null and lable it. Or get rid of the null and use a slider.