Rube Goldberg #3 Steps & Changes in the Plan

As I said in my last post, I intended to make 2 more blog posts. This post is to clear up our steps, share our changes in the plans, and explain in pictures what we are talking about. First I will clear up our plan (Look at the pictures below to help).

1-2 : Our first step was to have a robot push a car in the opposite direction of a springboard. On this springboard there are weights keeping the spring down, full of potential energy. These weights are attached by a thick string, to the car. When the car moves in the opposite direction of this springboard, it pulls the weights off with it.

3: The springboard that is now released has a ball on it. When the potential energy turns into kinetic energy the springs leaps up, throwing the soccer ball off.

4: This soccer ball, then hits a piece of wood that has a cup full of rocks balancing on top of it. “Why rocks?” you may ask. This is because we need a weight in the cup. This will be explained more in the next step.

5: The cup of rocks will fall. There are more weights, but, they are held on with velcro, ever so slightly, that even one push or tug of a heavy object will make it fall to the ground. This is where our cup of rocks come in. Once those rocks tug on the weight with velcro (they are attached by a string), the weight with velcro falls to the ground.

6: This weight just happens to be attached to a pulley. On the other end of the pulley is a few books. They were only held up because of the weight on the other side. Since this weight is no longer there, the books fall. This is not the end.

7: The books fall on a lever. A seesaw, basically. And when the books drop on one side the other side goes up.

8: This other side is wedged into a laptop screen, so then when the side goes up it opens the laptop screen.

Our changed plan:

  1. An RC car pushes a wedge that is on a ramp.
  2. This wedge is what is holding a plastic car from going down the ramp. The slightest push and the plastic car goes rolling down so when the wedge is pushed the car goes rolling down and pulls the weights with it.

3-8. Stay the same.

Why?: We decided the robot probably wouldn’t have enough power to push the car. This is because if the car is attached to the weights you have to add the weights weight and add that to the car. If you estimate that a small robot probably wouldn’t be able to push that car. But, an RC car is more powerful and, with the car on a ramp we also have the advantage of gravity, because it is easier to make it go down.

This is the ramp, car, and wedge
This was our original first step
This is the lever

Rube Goldberg #2 Steps & Energy

As you already know if you have read my previous post, we are doing a Rube Goldberg Machine project in class. We have to write down a materials list and a written plan down on paper. We also had to see what energy transfers throughout our project. Here is a list showing my groups steps and the energy between the steps.

  1. Rc car going down a ramp = potential energy Ô×íkinetic energy
  2. Hitting car thus pulling off the weights = energy transfer = kinetic energy from rc car to plastic car to string. This leads to the weight being pulled off
  3. Since the ball was sitting on a spring board that had potential energy. Then it was kinetic energy when the weights were pulled off.
  4. The ball hits the cup that is balanced on a piece of wood. The cup has potential energy that is then transformed into kinetic energy when the balls knocks the wood out from under and the cup falls.
  5. The pulley which also has kinetic energy is put into action then the books drop on the lever which is now uneven opens the laptop because the higher side is on the side of the laptop.

This may not be very clear and may not be how this project will be when it is done but, I intend to make 2 more posts. One further explaining the process of this Rube Goldberg project ( as in showing pictures of our plans and clearing up what they are, what different designs we have, what we might reconsider, etc.). Another showing a video of our finished product and explaining the changes we had to make.

Rube Goldberg

In class, we have started a project called Rube Goldberg. Now as some of you may not know Rube Goldberg was a person. His real name was, Reuben Garrett Lucius Goldberg. He was a cartoonist, author, sculptor, engineer and inventor. We now have machines that we call Rube Goldberg machines. That is what we are building in class. We have detailed sketches and research. We have to go through the whole design process. Testing and re iterating. We still have to finish building. Next post I will try to show pictures.