Animate Assembling Objects
Written By Irascibleone
To create an assembling effect in an animation in Blender 3D, we will use the particle system and an explode modifier to made our object explode, then reverse the explosion in the sequencer.
Get an Object
Let's start by opening up Blender. If you have the default cube, you are in luck, today we are going to be using it. If you don't have it, add a cube to your scene now. Or the monkey. Or anything. You can use any mesh you like for this tutorial, so long as it is a mesh.
Once you have your object in your scene, select it and go into Edit mode. Subdivide you mesh a few times. You can find the subdivide button in the Mesh Tools sidebar (Press T in the 3D View window). We are doing this so that when we explode our object, there will be smaller pieces flying about. Be careful though, subdivide too much and you might slow your computer down.
Since our editing is complete, let's head back into Object Mode. To make objects explode, we need to use the particle system. This is because the pieces of our object will cling to the particles when they are emitted. Our object will act as the emitter.
Select your object, go to the Particle Settings, and click on the plus button to add a particle system. In the Emission section change Lifetime to 100. In the Velocity section change Normal to 0.000 and Random to 2.000. In the Rotation section change Angular Velocity to 0.500. Lastly, in the Physics section change Size to 1.000. These changes will help make the cube explode (and later assemble) in a more random manner.
Ultimately, you can change these settings to whatever you like. None of these are really required to get the mesh to fall apart, so feel free to fiddle with the settings to get the look you want.
To make your object explode we will use a modifier. Open up the modifier settings and in the Add Modifier dropdown select Explode. If you test out your animation now, you should see all of the faces of your object fall apart.
Before we move on to assembling our object, you may notice that the particles themselves are appearing in the rendered result. To solve this problem, you can go to the particle settings and there should be a section labeled Render. Change the Halo setting to None. This will hide the particles when you render your final result.
To reverse the animation we are going to be using the video sequencer. You can change the layout of blender to Video Editing with the dropdown list directly to the right of the help menu. After you have done that, click on the Add menu in the sequencer window and select Scene. This puts our current scene into the sequencer for us.
Make sure the scene is selected in the sequencer and open up the strip settings in the right side of the sequencer window (press 'N' if it is not there). If you scroll down in that sidebar, you will eventually come across the Filter section. Check the Backwards box and your strip will play in reverse.
With that, I'll leave you to it! Now you know a quick way to make a mesh explode and assemble back together.