Object moving under dirt.

I’m trying to get a realistic looking animation of an object moving under a couple inches of dirt. Like when you are at a beach, and run your hand through the sand, it flows over top and comes back down. Or in some animations where something is burrowing under the ground, and it makes the surface react and push up, but then come back down.

I am currently experimenting with wave modifiers on a plane that match when the object moves through the area, but it seems like there should be a way to get the plane to just react and push up when something is moving underneath it. Or generate enough particles to have the object move through? I am fairly new to Blender and animation, so I thought I would see if any of you experts have done this before.

I would greatly appreciate ANY advice or ideas on how to get this effect. Thanks!

Simple bulge can be moved across ground plane by the use of Lattice modifier animation.


Let me make the general suggestion that you should plan your approach, for most effects-work, in pieces or stages.

In other words … you would start by working with ridix’s (very good…) suggestion for getting the “bulge and movement” part of the effect down. Even though the bulge is moving along an unadorned plane, it’s clearly the first step. Furthermore, it is generating the basic movement that you are looking for, among the hundreds of vertices and edges and faces which make up the plane … any of which you can use as sources of influence to control something more-elaborate.

The next artistic question that you might consider, having accomplished “step one,” is exactly how you want this motion to perturb the surface. Do you want it to look like “sand on the beach” (which will feature some kind of spilling-sand effect)? Or, “a mole burrowing under a grassy lawn?” Or, “a mole burrowing through the parched earth of Arizona?”

Now, consider (and write down…) what are the visual characteristics that will “sell” each of these effects to you and to your audience. Try to order them from “most essential” to “nice to have.” Also, consider how several of these characteristics might be layered or combined to add to the final effect. If you happen to have a mole in your backyard, get out there and observe the damage.

Also, study Blender 2.5’s many “node-based” features … compositing, textures, materials, and more. Surf the Internet looking at “shot breakdowns.”

I like to keep a diary, or notebook. It’s a loose-leaf 3-ring binder and a small set of number-two wooden pencils, with a carry-with-me sharpener on a short piece of string and a small Velcro patch.