pulling a cart

[cynthia]

Hello clever riggers,
I have a cat pulling an overloaded cart. The cat's walk is an additive relative walk cycle with a built-in up and down. The cat and cart are one skeleton. However, I don't want the cart to go up and down with the cat's walk. I do want the contents of the cart to sway back and forth with dynamics. I would be most grateful if anyone could please suggest a solution that will keep the cart from bouncing up and down? Maybe the cat's arm pulling the cart should be stretchy? Also I don't know why my cat has a limp. Here's a link to a video. ( I never seem to be able to make my video appear in my post. [vimeo]197136518[/vimeo])
https://vimeo.com/197136518
Many thanks

[synthsin75]

Since I don't know exactly how you've rigged/animated it, I can only show you how I'd do it.

http://www.filedropper.com/wagon

[cynthia]

Hi Synthsin,

Thank you for whipping up that rig so fast. I tried to duplicate it with my character but my character's legs didn't connect with the rest of the rig. Here's a link to a library folder containing the character and animation as I first constructed it. https://app.box.com/s/yk1ilru3paze99nibtgqhrk0zn9jijty

[synthsin75]

Here you go. Let me know if you have any questions.

http://www.filedropper.com/skeletoncatedited

[cynthia]

This is wonderful! thank you so much! Can I just review with you what you did?

It looks like you added B38 and made it a child of B17, then made B38 the target of B7. Is that right?
That's so great. I couldn't see how to make just the handle of the wagon move up and down and not the whole wagon.

Many, many thanks for this valuable lesson. It's very generous of you

[synthsin75]

Yeah, you've got it. I also unparented the handle (B7) from the hand, parented it to the wagon (B34), and made the cat's root bone (B10) control the position of the wagon (B34) on the x-axis only (so the wagon doesn't rise and fall with the cat).

Glad I could help.

[cynthia]

I didn't realize you could choose to confine the influence of one bone on the other to the x axis. I've just finished an app with a pile of sprite animation for which I had to deliver coordinates to the programmers, so this concept makes sense to me. I'm fascinated to know how it's done in Moho - I've looked at your file again and can't see how you did it.

[synthsin75]

Select bone tool>Bone constraints drop down>Position control bone>X-axis and Y-axis fields.

[cynthia]

So the wagon bone B34 is selected, and in the bone constraints menu, "Position control Bone" means the root bone of the rig? In the coordinates fields, these are not actual coordinates but the relationship or degree of influence between the wagon bone and the root bone? So your "1" in the x field means a 1 to 1 relationship between root and wagon, and in the y field, the zero means 0 influence?

[synthsin75]

Yep. Sounds like you have a good handle on it.

[cynthia]

thank you very much, indeed!! this info went straight into my "Moho tips" document, which is full of stuff I learn from the forum and tutorials.

[synthsin75]

Glad to help.