Stepper motors and motors with encoders are the muscles of robots.
Stepper motors have a magnet in them and a set of electromagnets push and pull them around. Motors with encoders have a disc at the end with lots of little bars and an eyeball that counts how many bars have passed.
Watch the video to see what they look like on the inside. Robot making is hard if you don’t know what you’re doing, I was lucky enough to stay up all night last night until daybreak with some robot-making friends and we got my computer set up to talk to the Make: controller and made an LED go on and off. More about the robot making get-together I went to in tomorrow’s robot installment.