parenting in physics???

i am using blender to make a simulation game for my schools robotics team, and im having a small problem. i need the “robot” object to have a bucket to hold the game peices you pick up, to solve the concave problem, i made the bucket im multiple peices, then parented them to the body. they move with the robot, but they are not taken into account when you colide with something. i have tried different combinations of setting in the logic pannel, but nothing is working. in all the examples i see this works fine, but just not working for me. any help would be greatly appreciated!:slight_smile:
p.s. it needs to go up a ramp (a.k.a have rolling physics)

um . . . anyone out there? it seems a simple problem, and i have seen it done in examples and mimicked them, but to no avail. i realy do need the help as this concept will be used several times in the game

am not quite sure with what you meant here…

but they are not taken into account when you colide with something.

what i mean is that they are like ghost objects.
when stuf falls into the bucket, it ignores the sides (which are seperate objects, parented to the bottom of the bucket) and rolles right out.
ive seen this done in examples, in fact, in that rube goldberge bullet physics contest there is one that has a bucket that is made like this. i looked at the blend and copied what was there, but when i trie it the objects ignor all the children, like ghosts.

Im not sure why you made the bucket out of separat objects instead of just making a tube and deleting the top faces.

But did you make all the faces collision detected in uv face mode? And I dont have any experience in this, but maybe the normals need to point to the inside? and to show a texture, make it two sided perhaps.

Hope that helps

Im not sure why you made the bucket out of separat objects instead of just making a tube and deleting the top faces.

that wouldn’t work i guess. even if your object is a top-less cylinder, the closest collision type that you can assign is still a cylinder (with tops). biskit333 i think did the right thing by making the bucket into a number of objects.

EDIT: is it possible for you to post a blend? i tried what you said (parent parts of the bucket to something) and it’s working fine for me.

heres my .blend, any help you can give is great
right now im working on making a fallback if this doesnt work
the controls on the blend are arrow keys to move, wasd to rotate camera
the green thing is the robot, and ive made the wheel a different object, parented, so i can test the concept (at the moment, the wheel goes through the floor) if you can get that working, i can impliment it on the other parts

ok just wondering, does your logic panel include buttons like “Ansiotropic” and “do Fh” and stuff? Because up until today, mine did not. then today, blender crashed for some reason, and when i opened it back up, those buttons were there. more importantly, the parenting worked!!! im wondering if everyones has these buttons, and why mine just showed up like that.
either way, ITS WORKING NOW!!!
(now time to get the whole thing done by wednesday . . .)

Those buttons have been removed in newer versions of Blender. It sounds like you somehow reverted back to an older version of Blender. What version number displays in the top menu bar of your blender window? Anyway, if it works fine in that version, there’s no reason to switch back to the other one you were using. “If it ain’t broke, don’t fix it.”

BTW, I think the correct way to solve the problem you were having earlier in newer versions of Blender is to select the bottom of the bucket, then click “Bounds” and “Compound” in the Logic Panel. I’ve never used this feature, but I believe it works with simple parenting like you’ve done.

(I remember my high school robotics team… another team member showed me a cool program called Blender… version 1.70. “It’s not professional quality,” he said, “but it’s a great way to learn 3D animation for free.” Strange how that reminds me of the things that people are saying about a certain Game Engine I know of…)

wow, thats almost creepy (but btw, im in a middle school robotics team going to the state competition against all high schoolers (best middle school for this competition in the country yo!)) but anyway, i tried the compound thing, and no such luck. but i agree, if i can get it working in the old version, ill use that and then figure it out after the competition this saturday.