It turns out we didn’t play the “Self-Driving Car” game this Friday. Instead, we made the switch that our projects are going to be connected to on a breadboard. For the switch, we used a breadboard, jumper cables, a battery, and an LED light. This is a breadboard:
In class, we learned about parallel and simple circuits. In a parallel circuit, if there are multiple lights, and one of them goes off, the rest of them stay on. In a simple circuit, if one light goes off, then the rest of them go off too. That’s because of how the switch is built. In a parallel circuit, the wires attached to each light are connected to the wires that are attached to the battery. And each wire that is attached to a light is separated from the other wires. That’s why if a wire attached to a light gets cut off, then that light will go off, but the others won’t. Here are some pictures of the three different switches all put together:
On Sunday, Nick and I finished building and recording our entire machine. It has 17 steps. We got a successful run on our SECOND try! It was awesome. When we just started working that day we replaced some steps. For example, we replaced the marble and cardboard tubes with a labyrinth and wooden maze that the marble goes through because we realized that taping the cardboard tubes to the wall wouldn’t work because the tape wouldn’t be strong enough to keep the tubes on the wall. We also took out the soda can and the two cars and swinging bar step. We replaced that because we realized that the swinging bar that gets pushed by the first car wasn’t strong enough to give the second car a good push. Also, we decided to replace the car hitting the books because every time it did, the book would fall backwards because the car was hitting it on the bottom. A final step we replaced was the books at the end that push the soccer ball into the goal. We replaced that because we wanted to get to put in a cool domino part with one domino going on a loop-the-loop and other dominoes on this little thing that has like a wave shape. We really like the dominoes falling.
We also made an important change to the phone step. When the phone received the call from the computer, the word “Mami” appeared on the screen (which is mom in Spanish), so we thought it would be funny to change the name of the caller to “Rube Goldberg”. My dad was there filming and had the idea of putting voiceover when the computer calls so that the people watching our video will hear what’s on the phone’s screen.
When we finished building our machine, my heart was racing. I was so excited and at the same time nervous. Would we get it to work? How many tries would it take? It didn’t work on the first try, but it got pretty far. Nick and I were SUPER frustrated because it was two steps away from working all the way! The step that failed were the mini dominoes hitting the bigger ones. The mini dominoes weren’t strong enough to knock down the bigger dominoes so we figured we had to replace them with the bigger ones. We made that change and… IT WORKED. We couldn’t believe it worked on the SECOND attempt. Nick and I were celebrating like crazy!