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sebrady
08-27-2009, 07:12 AM
I need to find a way to rotate a front end loader. see pic.

There is a long middle arm that moves the hydrolics on top, back and forth based on how the long middle arm is rotated.

I need the lower "B" arm to push the scoop. I need the hole "A" and the arm "B" to stay lined up at all times. The pusher arm "B" always points to the hole but if the middle arm rotates, the scoop does not follow accordingly.

I know this is hard to explain. I hope there is an answer out there. Thanks.

Otterman
08-27-2009, 08:09 AM
1-you need to create two nulls at each pivot point of the arm. Call em 'pivotA' and 'pivotB'
2-have them target each other.
3. put 'parent in place on'....
5. and parent 'pivotA' to the bucket and 'pivotB' to the Loader arm (not the smaller one).....then
6. parent the smaller arm to 'pivotB'.

Providing your pivots are in the correct place-u should have a rigged bucket.

If you search through my post there should be a very similar rig for you to pick apart. I will see if i can dig it out

sebrady
08-27-2009, 08:30 AM
thanks, I did that for the hydraulics on the top half of the arm, I cant get the same result on the bottom of the rotating arm, I have 1 null at the center of the hole in the bucket, but I cant keep the hole in the bucket over the push arm...........even if I have a null on the push arm.

I'll try what you suggest. Thanks.

sebrady
08-27-2009, 08:33 AM
when you say arm..........do you mean the highlighted "B" arm in my photo.

Otterman
08-27-2009, 08:37 AM
Hey having another look at your wires-it doesnt look posible to achieve what your after with its current pivot position-what are you using as reference? From a single pivot arm it needs to be more like the attached image.

sebrady
08-27-2009, 08:52 AM
here are the LW files

Otterman
08-27-2009, 08:54 AM
Heres a quick n dirty rig i knocked up, it uses bones and IK and a goal null. Hava a lok and il try and walk you through it.

Otterman
08-27-2009, 08:58 AM
arh-i see how it works now-il try and crack this one for ya....

sebrady
08-27-2009, 09:10 AM
here is a screen grab movie

Otterman
08-27-2009, 09:19 AM
Here you go-excuse me if its a little rough n ready but i go home in 20mins.


....whoa-just noticed your using 8.5. I did this in 9.6 and it wont worky worky for you and i cant save down past 9....argh!

sebrady
08-27-2009, 09:49 AM
my path to 9.6 upgrade is coming very soon, but not soon enough. thanks for any help you can be provide though.

sebrady
08-27-2009, 09:50 AM
dang dude, you did it, cant I just use bones????????

Otterman
08-27-2009, 09:54 AM
Im off home in a minute-pm me tommorrow n il walk you through how i did it.

Try this anyways......

sebrady
08-27-2009, 10:38 AM
I have a demo of 9.6, can you send me what you have and I'll check it out and apply it to my 8.5 version. Thanks..............I hope.

gpdesigner
08-27-2009, 06:53 PM
Question . . how does that bucket move without a piston on it?
to me it looks like the only arms attached to it are pivot arms . . . I could be wrong but that is what I am seeing . .
gp

Otterman
08-28-2009, 12:51 AM
Question . . how does that bucket move without a piston on it?
to me it looks like the only arms attached to it are pivot arms . . . I could be wrong but that is what I am seeing . .
gp

it's a little difficult to decipher on the screen grab but examining the model itself-the loadarm ram pushes a kind of a rocker which has a fixed link that pushes on the bucket-see the above movie I did-it's usually how these things are rigged-trust me I work on loads of machines like this.

Sebrady-all you need is attached above-I managed to export the 9.6 scene down to a much earlier version (see last attachment)-fingers crossed itl work for ya. Let me know how u get on.