When I built my first RoverBot I had one goal in mind: make a robot that will wander around the house. There were a couple reasons why my first robot did not fulfill this goal. The first reason was that the RoverBot couldn’t drive on carpet. Most of my house is carpeted. The second reason was that the RoverBot only turned in one direction. This made it so that it couldn’t get to some places. An example of this is a square room with a door that swings inward and is halfway open. I solved both of these problems with my second RoverBot. To solve the carpet problem I gave this one four wheels instead of two. That way no part of the robot would be dragging on the ground. I also geared the motors down for more strength and less speed. The answer to the other problem was to make it so that when it bumps into something, sometimes it turns left and sometimes it turns right. I decided to make this decision random, or at least seemingly random. I did this by adding two blinking LEDs to the robot. One LED was always on and one was always off. They blinked about five times a second. When the robot bumped into something, they would stop blinking for a few seconds. If the left LED was on when it bumped it would turn left, and if the right LED was on when it bumped it would turn right. RoverBot II is 5.5“ long, 6.75” wide, and 4.5” high. This is slightly larger than my first RoverBot, but that’s ok. This robot took me less than one day to build. I was on spring break and I couldn’t think of anything else to do, so I decided to make a better RoverBot. The cost was nothing because I already had all of the parts. If you have any questions or comments (how to make my next version better?) e-mail me at firstname.lastname@example.org.