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clborrelli
02-18-2019, 05:30 PM
I am making a helicopter go from the ground to a destination, I would like to know how I can make the rotation of the blades on the top go faster and faster and then stop.
I use zero at zero then in on second or 30 frames, I create the rotation of the blades, will say for this the blades rotate 360˚ 4 times in 30 frames or my next frame at
30 will be 1440˚ - my question is is there a way in graph editor to slow the rotation down and speed it up. I usually use the repeat, pre and post but this project
is asking that I start slow go real fast then slow down again. If I wanted to make the rotation at frame 90 to go 2880˚ which would be faster, can it be done?
Is this possible ???

Thanks so much
Carol

ernpchan
02-19-2019, 06:34 AM
I would use this script to control your rotor animation.
https://youtu.be/1ZYD-AntO3E

MonroePoteet
02-19-2019, 05:29 PM
If you're using a version of LW that implements Bullet Constraints with Motors, you could use the Bullet Motors to spin up and slow down the rotors as well.

A sample scene is attached.

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MOV file (small): 144191

The simple helicopter has a main Hull layer, then MainRotor and RearRotor layers (should have named it TailRotor!). The rotors are positioned to their respective hubs on the Hull. To add a Bullet Hinge, select the MainRotor, hold down CTRL and select the Hull, and then push the FX Tools=>Constraint=>Hinge button. The Bullet hinge will be added, named "Constraint", connecting the rotor with the hull. The Hinge has to be rotated 90 degrees in Pitch so the axis of rotation is in Y. I then use ALT-n to rename it to MainRotorHinge for clarity.

To set up the Motor, select the Motors tab, enable Motors, and specify a fixed Motor Force (I used 3000). I then set up an Envelope on the target rotation speed, which I believe is in degrees per second (although I haven't researched or tested it). The Envelope initially sets the Target Speed to 1440, and then ramps it up to 2880 at frame 110, then down to -360 at frame 209 (to brake the rotor), and back to 0 to a full stop at the end.

Here's the MainRotorHinge setup:

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The same setup is done on the RearRotor (TailRotor), although the Hinge needs to be rotate 90 degrees in Heading to provide the correct orientation. The Envelope on the RearRotor is slightly different and doesn't need to be braked with the -360 target speed since it is much smaller in volume and has less calculated momentum.

The Hull is the main Bullet Rigid object, and is (poorly) keyframed throughout the animation. The Bullet Activation is set to "Start On Last Keyframe", and there are keyframes to the end of the animation, so it is never activated in Bullet (and falls through the floor due to Gravity!). Here's the setup:

144193

Have fun!
mTp

cbreton49
03-03-2019, 10:37 AM
Thanks all, I will look into the suggestions, what my goal is to slow the rotation down towards the end of the frames when it crashes.

cbreton49
03-06-2019, 10:31 AM
I am using LW 2015.3 I see FX Tools and there is Bullet in the list on the right but it is not activated. How can I activate this dynamica?
Carol

- - - Updated - - -

I am using LW 2015.3 and I see FX Tools and Bullet on the left but it is not activated, is there a trick to activate it ?
Carol

cbreton49
03-06-2019, 10:40 AM
I have never used scriipts, can you direct me on this, I downloaded the RotorControl scripts but I have no idea how to use it.
Carol

- - - Updated - - -

I am trying to use the Bullet but it isn't activated in my LW 2018.3 version, is there a way to activate it that I am not aware of ?

Carol

cbreton49
03-06-2019, 11:54 AM
Is this script for mac ? and is there a tutorial on how I add it to my Lightwave v 2018.3 ?
Carol

MonroePoteet
03-06-2019, 01:09 PM
I have never used scriipts, can you direct me on this, I downloaded the RotorControl scripts but I have no idea how to use it.

Is this script for mac ? and is there a tutorial on how I add it to my Lightwave v 2018.3 ?

Carol

- - - Updated - - -


In the Utilities tab, the LScript/RT button will invoke compiled LScripts (RT stands for RunTime). However, my attempt to invoke the RotorControl.lsc compiled script gives an error saying it "wasn't compiled for this architecture". I'm running Windows 64-bit not Mac, so you can try it on the Mac to see if it works, but if it was compiled for Win32 architecture, it won't work. The author didn't provide the architecture-independent LScript itself.



I am using LW 2015.3 and I see FX Tools and Bullet on the left but it is not activated, is there a trick to activate it ?
Carol

It sounds like you're looking at the "Group Header" labeled "Bullet". Bullet simulation is activated by choosing Objects in Layout and selecting various Bullet options such as Rigid Body, Kinetic Body, Static Body, Hinge (as a Constraint), etc.:

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You can activate the main Bullet panel with the Item Properties or World Properties buttons:

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Here is the LW2018 documentation with the Bullet overview, which is mostly applicable to LW2015.3:

https://docs.lightwave3d.com/display/LW2018/Bullet+Dynamics

I've attached a brief screen capture of setting up a very rudimentary Rotor with a Bullet Hinge and Motor:

MOV File: 144343

You need to be sure Left Click Select Object is enabled and SHIFT-Left Mouse Button to select the Rotor after selecting the RotorHub to set up the Hinge. Or, you can select them in order in Scene Editor.

mTp

MonroePoteet
03-06-2019, 01:41 PM
Here's an annotated version of the video setting up the Rotor Bullet Hinge:

MOV file: 144345

A quick note on Hinges (and other Constraints): in this example the Hinge is oriented so Bullet Gravity is pulling the Rotor down onto the Hinge. If it is at some other orientation you may have to add a Bullet 6DoF (6 Degrees of Freedom) Constraint to prohibit Linear motion.

For example, if you have a Tail Rotor to the side of its Hub, Bullet Gravity may "break" the hinge and the rotor will fall off. Adding a 6DoF with all Linear motions limits set to 0.0 will prohibit this.

mTp

P.S. In annotiations: "Use Envelope for Variable Speeds", not Envelop

cbreton49
03-06-2019, 02:28 PM
144346

My bullet doesn't seem to be activated ?

MonroePoteet
03-06-2019, 03:32 PM
Huh. Either the Bullet plugins haven't been loaded or the menu hierarchy isn't set up correctly. For LW2015.3, the Bullet plugins are located in the Dynamics.p file, which on Windows is located here:


C:\Program Files\NewTek\LW2015.3\support\plugins\animate\

In Layout, use the Utilities=>Add Plugins to find this file in the Mac's folder hierarchy and see if the menu items show up when they've been added.

If the menu items don't show up, you can try using Edit=>Edit Menu Layout and select the "Default" entry under the Presets pull-down to set up the default menu layout for LW2015.3. For myself, I created a separate main menu tab for Bullet to have separate buttons for each Bullet option. If you want that separate Bullet tab you can use Edit=>Edit Menu Layout=>Load to load the .CFG file in the attached ZIP file.

144347

mTp

cbreton49
03-06-2019, 04:28 PM
144349144350

I have searched and searched and cannot find the Bullet Plugin anywhere? would that be the attachment you added ? i am looking in animate is that wrong?

MonroePoteet
03-06-2019, 07:05 PM
Looks like the extension for Mac plugins is "plugin". Try the Dynamics.plugin with the Add Plugins.

mTp

BeeVee
03-07-2019, 03:02 AM
Actually, probably best to go into the Menu Editor with Alt-F10 and Restore menu default by going into the Presets dropdown and choosing Default. Bullet is an integral part of LightWave.

B

cbreton49
03-07-2019, 11:51 AM
I like your idea but I have done that an it doesn't seem to work. I downloaded another version of LW 20018.0.7 and it's there so I'm going to try and adapt to that version as the Bullet is there and active.
Thanks for your help. The interface is really dark so I am dealing with that issue at present, seems to be always something....
The working area is black and I can't seem to change the color, any ideas ??144353144353
Carol

cbreton49
03-07-2019, 12:38 PM
Figured it out, thanks for everyone's help, gonna try using bullet now.....
Carol