Robotic Arm Edge
While it appears to be something from a sci-fi movie, this technical-looking robotic arm is surprisingly simple to assemble. Encased within yellow and black plastic, the gears enable motorized wrist movement of 120 degrees, elbow movement of 300 degrees, base rotation of 270 degrees, and the ability to lift up to 100 grams of weight up to a foot. The gripper "hand" also features an LED light to locate objects in the dark. The controller holds five switches for manipulating the robotic arm, and a safety gear audible indicator helps prevent potential gear breakage while experimenters are testing its limits. Instructions are completely pictorial, with clear drawings and pieces numbered for assembly. So what could you do with an extra arm?