This second volume of The LEGO® Power Functions Idea Book, Cars and Contraptions, showcases small projects to build with LEGO Technic gears, motors, gadgets, and other moving elements. You ll find hundreds of clever, buildable mechanisms, each one demonstrating a key building technique or mechanical principle.You ll learn to build four-wheel drive cars, adorable walking bots, steerable tanks, robotic inchworms, and cars that can follow the edge of a table!Each model includes a list of required parts and colorful photographs that guide you through the build without the need for step-by-step instructions. As you build, you ll explore the principles of gear systems, power translation, differentials, suspensions, and more.