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Skinner3D
08-26-2007, 02:56 PM
On my p-61 (which is shown on another thread) I need to rotate things like landing gear bay doors, flaps, ailerons, etc. All of which do not lie nicely along the x,y, or z axis. How do I go about making these work? I would like to use morph maps, but I can't get the pieces to rotate along a certain edge.
Is there a way to define a group of points or edges to act as a hinge group or do I need to do something other than morph maps?
:help:

cagey5
08-26-2007, 03:01 PM
I would add a null for each rotation item, line that up on the required axis and parent to it.

Skinner3D
08-26-2007, 03:09 PM
That is a good idea and I will try it.

Is there anyway to do this in modeler?

cagey5
08-26-2007, 03:13 PM
Not so far as I am aware. You can move pivot points for each later but not rotate them. Until someone tells me otherwise.
But it's dead simple to do in Layout anyhow.

cagey5
08-26-2007, 03:25 PM
That should of course of read '.... for each layer ....' 5 minute edit limit.... grumble, grumble.

Ztreem
08-26-2007, 04:14 PM
Not so far as I am aware. You can move pivot points for each later but not rotate them. Until someone tells me otherwise.
But it's dead simple to do in Layout anyhow.

You can rotate around pivot points in modeler, just change mode to pivot instead of mouse. That way you can test if your pivot point is in a good position.

cagey5
08-26-2007, 04:23 PM
I understand that, but you can't actually rotate the pivot point as far as I know.

Surrealist.
08-26-2007, 10:42 PM
On my p-61 (which is shown on another thread) I need to rotate things like landing gear bay doors, flaps, ailerons, etc. All of which do not lie nicely along the x,y, or z axis. How do I go about making these work? I would like to use morph maps, but I can't get the pieces to rotate along a certain edge.
Is there a way to define a group of points or edges to act as a hinge group or do I need to do something other than morph maps?
:help:

It seems to me that the easiest way than nulls or even bones is to set it up right from modeler.

Since the angles of the wings are oblige and thus the pivot points will be so - in layout - you need to set up your moving parts so that they are in parallel/perpendicular alignment with XYZ first. This will have them rotating from a native HPB that is in alignment with the part. (Tip: Use numeric pannel to bump part at less than 1 degree so it is in alignment. Another tool is rotate to ground.)

Then they should be centered (or pivot point adjusted) so that they will rotate from the proper axis point when positioned on the wing in layout.

In layout simply position it to the oblique angle of the plane part (wing etc.)

(It is much easier to position a part. A null has to be parented and unparented to readjust the part. Bones need to be activated and unactivated to keep testing the rotation.) Otherwise the rotation will be off from the orientation of the part.

Once positioned switch to Coordinate Local Axes and it will rotate properly from its position. To readjust simply set it back to parent and rotate then to local to test and for animation.

To me that is much less work in the long run and you have less things cluttering up your animation.

SplineGod
08-26-2007, 11:58 PM
Some things you can use endomorphs on since they dont rotate much. Others you can parent to nulls and rotate the nulls into the proper positions. Its also possible to use bones as well. Each part can have its own set of bones or you can make everything a single piece and use bones and endomorphs.

Skinner3D
08-27-2007, 02:17 PM
Thanks guys that helps a lot:D

From my limited knowledge all of these different methods will work with expressions, right?
Which one would be best? I am trying to get it so that all I have to do is animate the path that the plane follows, and the control surfaces are automatically adjusted to make it look real. (Attempting to follow the tutorial from Inside Lightwave 7)

Thanks again for the help so far

If expressions work like I think that they do, then the above question might be a very stupid question :o

Surrealist.
08-28-2007, 12:28 AM
The Expressions will simply automate or trigger rotations and such based on some other input so that would work fine providing you have your rotations set up correct. Once you have that then all will be fine. A bank rotation of the plane can trigger each flap and so on.

Mess around with a simple plane wing and a flap just as a simple way to test it and you'll see exactly how the oblique angle really needs attention based on how I described the set up.

If it were me - especially with expressions - I would try to keep it simple and have less controllers.

Skinner3D
09-02-2007, 11:37 AM
I am stuck again:D

I got the front landing gear doors to rotate, but the flaps are giving me a headache. :bangwall: Is there anyway to use more than one pivot point on an object? Or is there anyway to fix points? When I set up the flap it wont stay in its socket even when I only manipulate one rotation axis.

SplineGod
09-02-2007, 11:54 AM
Lets say you would normall have the flaps parented to the wings but you need to rotate the flaps because the wings arent straight out from the sides and are swept back.
Create a null and parent the flap to it. Place the null and rotate it so that flaps in the right spot. Now when you pivot the flap it will do so relative to the null.
If you need to have more control, parent the first null to another null and so on.

Skinner3D
09-05-2007, 07:35 PM
:D My frustration levels have offically reached the point at which I almost give up :D
Anyway, here is a zip file with a basic scene and part of my p-61. I set up one of the flaps, and it is the best I have see so far (by just rotating the green handle), but it still has problems especially on the outboard end of the flap.
Could some of you please download this and either see what I am doing wrong or try out some of the things that you have been suggesting?
If you get it working so that the two corners of the flap that are not on the edge of the wing don't move using simple rotation (because I have to express it later :D) I will be forever grateful.

SplineGod
09-05-2007, 08:48 PM
Theres a couple of things I would look at.
I looked at some blueprints and they indicate that the line along the flap is straight not curved. If its curved theres no way to get it to rotate and look correct.
The 2nd thing is that where you have the null probably isnt quite correct.
You have to worry about lining it up to rotate correctly from above along the edge of the flap AND from the front view along the edge of the flap since the wings arent straight out to the sides.

akademus
09-05-2007, 09:29 PM
how about changing Coordinate system from Parent to World or Local. It works sometimes for me when I have weird or impossible rotations. Just a thought

Skinner3D
09-08-2007, 07:49 PM
It is starting to look like several of my movable parts have to rotate on at least 2 axis in order to stay in postion. I think morphing is going to be my best bet in these situations, but can morph maps go across several layers?
As in layer 3, 5, 6, 2 etc all use the same morph map or do I have put them all in the same layer and then morph?

SplineGod
09-08-2007, 07:54 PM
Do the flaps on the real plane rotate in 2 axis? If not you should make sure youve got it modeled properly.
You can have multiple layers and tie the morphs of the other layers to the morphs of the first layer using channel follower, cycler etc OR move it all into a single layer and use one set of morphs.

Skinner3D
09-08-2007, 08:23 PM
It is good to know that I can tie morphs together. I think I will use that method for now unless someone thinks up something easier.
As for the real plane I really dont know. I haven't ever seen one in real life; although I really wish I could get the chance to see one up close. All of this work has been done off a set of blueprints and couple of pictures.

Surrealist.
09-10-2007, 12:23 PM
Looked at your file - nice model!

Unfortunately I don't have time to mess with it but your problem is a classic case for the solutions I outlined. This will give you a simple rotation - set to local after you position it in Layout.

Simplified:

1) Rotate layer with flap so that it is perpendicular to the XYZ. ( you cam make note of these rotation amounts) In Layout rotate to set the flap back in place ( use noted reference rotations from modeler if you want it exact)

2) Set to local and rotate on pitch.

Giacomo99
09-10-2007, 02:26 PM
What Larry said: your flap is curved, and the null doesn't look to be lined up quite right. This accounts for part of the problem

The far larger problem is that in the file you sent, you have "Coordinate System" set to "Parent." I switched it to "Local" and everything worked fine.

("Coordinate System" is under "General" in the "Modify" tab.)

Skinner3D
09-15-2007, 04:07 PM
I think I see what you guys mean about the different coordinate systems. I went ahead (before I had read the posts just above :foreheads) and created morph maps for all of the control surfaces. The only thing left to do is the landing gear bays.

Dumb question, where is channel follower or cycler? I can't find them in either the motions properties window or the normal properties window.

Ztreem
09-16-2007, 05:29 AM
Cycler and follower is in the 'add modifier' window in motion options.

metallo
09-19-2007, 12:25 PM
why on earth can't modeler rotate the pivots? seems like a simple thing to do and it would seem to eliminate monkeying around with an object in layout when it's perfectly arranged in modeler!

Skinner3D
09-19-2007, 05:20 PM
:confused: I think that I found cycler and follower but neither of them have controls to follow an objects morph. Am I missing somthing or is it not possible to express morphs?

metallo
09-19-2007, 05:31 PM
skinner,

i'm doing the same thing you are now, rigging an aircraft. i've decided the best way to do it properly is to use bones. create skelegons along the hinge axis for each surface. go to layout and convert skelegons to bones for the each control surface. animate the pitch axis of the bone to rotate your control surface.

unfortunately, if you deform or flex your wing with a morph map, it won't quite work right when you animate the bone and the morph at the same time. in that case, use a combination of morphs is probably the best.

regarding morph maps and expressions, you can definitely add expressions and modifiers when you edit the envelope on an objects morph. double click the morph mixer in "object properties" panel, click the envelope box "E" and you'll see you can do the usual stuff using the graph editor.

SplineGod
09-19-2007, 11:46 PM
:confused: I think that I found cycler and follower but neither of them have controls to follow an objects morph. Am I missing somthing or is it not possible to express morphs?

Cycler is a channel based version of cyclist and allows control over other channels besides, x,y,z, h,p,b etc. I use it with morphs all the time.
Channel follower is a channel based version of follower and also works with morphs.