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sticks3d
01-26-2008, 04:53 AM
I am trying to animate a water wheel with 48 vanes (or buckets.)
I want the water in one bucket to morph to the next bucket below as the wheel is turning (anti-clockwise at one revolution in 180 frames at 24 fps.)
I would like to tie the water morph object to the rotation of the water wheel.
At 0 degrees there would be the base water object and at -7.5 degrees there would be 100 percent morphing.
Then, as the wheel turns further, the process would repeat.
At -7.5 degrees there would be the base water object and at -15 degrees there would be 100 percent morphing.
Each of the water objects on one side would have a separate morph to the next bucket down.
All my attempts to make an expression have failed and key framing does not allow any variations in water wheel rotation speed.

meshpig
01-29-2008, 10:02 PM
Hi

Sounds challenging. A water wheel as in driven by water or a wheel which buckets water from one level to another?

A few things which aren't clear;

-Do the buckets remain level?
-What expressions have you tried?
-Why doesn't key framing give you variation in rotation speed?


Perhaps a pic would help?:)

m

sticks3d
01-30-2008, 06:34 AM
Hi - thanks for looking.
The water wheel is like an old mill.
I want to animate the water driving the wheel. Eventually I may try and model the rest of the mill with grinding stones.
The water pours onto the wheel from a trough and drives the wheel.
The wheel's variable rotation speed is up to one revolution in 180 frames.
The water will come into the first bucket (vane) and the morph will give the illusion of following the bucket into the new bucket position at 7.5 degrees later.
I only did the water morph for the first 2 buckets. I don't want to model the rest until I solve the morph speed problem.
I added an expression for the morph in the graph editor water morph group (from help I received from another post.)
[wheel_02.Rotation.B]/360
The problem is that it goes from 0 percent to 100 percent morph in 360 degree revolution of the wheel.
It needs to go from 0 percent to 100 percent morph in 7.5 degrees.
I've attached the scene I have so far.

meshpig
01-30-2008, 03:17 PM
Cool. How do you mean the rotation speed is variable?

-I'll give it some more thought later but it seems to me the wheel is turning too fast for something that size?? and the morph needs to be one complete object like a chain maybe, because it leap frogs over itself.

In which case you'd only need to graph the morph. , also can't see where the expression is applied?? You will need one for the wheel and one for the morph??

See what other people say.

m:)

Hopper
01-30-2008, 08:49 PM
...I'll give it some more thought later but it seems to me the wheel is turning too fast for something that size??
Maybe not so much at 24fps

sticks3d
01-31-2008, 03:26 AM
You are right about the wrong speed of the wheel. I calculated wrong.
If this particular water wheel turns at 8 rpm.
That makes one rpm (or 360 degrees) in 7.5 seconds.
If my frame rate is 24 fps, then one revolution of the wheel would take 180 frames (or 90 degrees in 60 frames.)
This was at maximum water flow rate. The speed of a water mill is controlled by the water flow (i.e. less water means less rpm.)
As the water in the buckets move towards the ground, it starts spilling out.
That's why I thought morphs were the best way to simulate it.
It would be just a repeating series of morphs.
I only modeled the first bucket of water for now. The expression is in the graph editor for the morph channel of the water (I don't know why it was missing in the other scene.)
I made a new scene (see attached) with the correction.

sticks3d
02-01-2008, 10:20 AM
I finally got it to work with a little help from the 'mod' function found in the copter tutorial.

http://www.newtek.com/lightwave/tutorials/animation/copter/partIV.html

The scene that works is attached.

meshpig
02-03-2008, 03:25 AM
I finally got it to work with a little help from the 'mod' function found in the copter tutorial.

http://www.newtek.com/lightwave/tutorials/animation/copter/partIV.html

The scene that works is attached.

S3D

OK, I see it now, the expression is very cluey! I still reckon it's rotating too fast.

-Scene swapping is cool, hey?

... what do you make of this where the 3rd hydraulic ram is not connecting with the bucket hierarchy?

The schematics are sort of organized.

m:)

54410