Did you know SketchUp models can move?
This book will show you how to get started with Sketchy Physics. You'll learn how to set up your models, add joints like hinges and motors, and how to modify 3D Warehouse models to become physics-ready. PC or Mac.
Please note: Sketchy Physics currently works with SketchUp 8; it does NOT work with later versions. If you don't have SketchUp 8, you can find it on freeware sites though they may not be trustwothy.