Animating an object that is constrained to character rig

[hollydepe]

Hello, I am trying to animate shopping bags that are on a characters arms and right now the bags are constrained to the elbow control on the rig so they follow her arm movements. I am unable to animate the bags because they are constrained so I tried to add a locator. If I constrain the elbow control to the locator the locator follows the rig. However, if I try to parent the bag to the locator so I can animate it, the bag and locator no longer follow the rig and are stuck in there original position. I am not sure what to do so that I can animate the bag freely while also having it stay connected to the character's arm. I read about grouping and constraining to the group but I don't know how to do that. I added the bag to a group too then tried to constrain but that didn't work either. Any help or suggestions would be great.

[stephenkmann · Accepted solution]

parent the bag to itself to create a new group. 

name that group bag_CTL

parent bag_CTL to itself to create a new group

name that group bag_OFFSET

constrain the bag_OFFSET to the elbow of the character. 

use bag_CTL to animate the bag. 

you can parent the bag as many times are you want to make lots of controls.,  and then just parentConstrain the top group to the elbow. 

hth

-=s

[hollydepe]

how do I parent the bag to itself? 

[stephenkmann]

Select bag 

edit - group 

 or 

 ctrl + g 

[hollydepe]

when I parent the elbow control to the bag_offset group, the bag does not stay on her arm anymore. It is is following next to her arm but not on her arm.

[stephenkmann]

Start over 

 Unparent the bag so it’s just the bag 

 delete the other groups you created and the parent constraint.  

Now.  Parent the bag to itself. A few times 

 then move the top group to the elbow 

 now make the parent constraint 

 ( select elbow first. Then shift select the top bag group.  Then make the constraint and in the options make sure “maintain offset “ is on ) 

[hollydepe]

thanks! i think I got it! the problem was there was a key on the bag and that's why it was changing position

[hollydepe]

this is another issue i am having you may or may not know the solution to but everything works fine in the viewport however sometimes when I scrub the animation, the bag moves back to the original position instead of where it's constrained but then I scrub again and it's fine. When I playblast, the bag is in original position and not staying where it should be constrained to the arm. I have this problem sometimes with other objects in my scene when playblasting. Do you maybe know why this is or how to solve it?

[stephenkmann]

Try using DG instead of parallel 

•     Windows | settings and preferences | Preferences.. 
•     find the "Animation"  section.  and at the top of the options, change Parallel to DG 

or This could also  be an update issue. 

• Make sure you have the latest version of Maya ( which i believe is maya 2020.2 ) 
• Make sure your drivers for your gfx card are updated. 

hth

-=s