Rube Goldberg Machine
A Rube Goldberg machine is a series of simple machines that are used to complete one task.
Two other classmates and I built our machine over the course of about 3 weeks. Our machine starts off on an incline plane that a marble rolls down and falls into a ferris wheel and falls into a tube. Next the marble rolls down the tube and into a cup that makes the pulley pull up a rocket. On the other side of the machine, another ball goes down a series of switchbacks and down a drop onto a lever that pops a balloon with a nail.
During this project we learned a lot about physics and how they are related to our machine.
Construction Log
Day 1: Screwed in ramp and painted it
Day 2: Found items to create ferris wheel, and drilled in ramps to make switchbacks
Day 3: Created drop tower with wood on the outside so the marble doesn't fall out
Day 4: Put cardboard carts onto the ferris wheel and painted and put the ferris wheel on our board
Day 5: Drilled in the tube that the marble goes through
Day 6: Made the pulley
Day 7: Perfected the lever that pops the balloon
Day 8: Painted our board to fit the Toy Story theme
Day 9: Practiced our presentation and fixed little problems.
Original Blueprint
This is the original blueprint for our Rube Goldberg project. The original blueprint was much more complicated than what our final product ended up being. The original blueprint does not include measurements. Once we started working on our project we realized that we would not be able to use all of the original ideas. It would have been a bit too complex.
Final Blueprint
This is the final blueprint for our Rube Goldberg project. Our final blueprint is much more simplified but it includes measurements and it is fit to scale of our actual project. The layout of our design is almost completely changed but it still includes a few of the simple machines.
Simple Machines Used
- Inclined Plane (In Step 1, marble 1 rolls down an inclined plane)
- Wedge (In Step 10, the lever is held in with a nail, an example of a wedge)
- Lever (In Step 10, a lever is used to pop a balloon by putting weight on it.)
- Wheel and axle (In Step 8, a car drives down an inclined plane into a cup)
- Pulley (In Step 8, a pulley gets weighed down by a toy car)
Calculations
Velocity
Velocity refers to the speed of something in a given direction. Velocity= change of distance/change of time. In our project we calculated the velocity of the marble going down the ramp. We found a velocity of .43 m/s by dividing the distance of the ramp by the time it took the ball to roll down it.
Acceleration
Acceleration refers to the increase in the rate or speed of something. Acceleration= change of velocity/change of time. To find the acceleration of the marble going down the ramp we divided the velocity by the amount of time it took the ball to get down the ramp. We got an acceleration of .46 m/s/s.
Force
Force refers to the push or pull of an object. Force= mass x acceleration. We calculated the force of a marble falling onto a lever. We multiplied the mass of the ball times gravity because it was free falling. We got a force of .5N.
Work
Work is the amount of energy that is put into something. Work= force x distance. To calculate the work of a marble falling into a cup we multiplied the force of the falling marble by the distance it was falling. The work was 2 joules.
Mechanical Advantage
Mechanical advantage can be calculated in two different ways. There is either mechanical advantage real or mechanical advantage ideal. The formula for MA ideal is distance of load divided by distance of effort. The formula for MA real is force of load divided by the force of effort. In our project we calculated the mechanical advantage of a ball going down a ramp before the pulley. We used MA ideal. We divided the distance of the ramp by the drop of the ball. We got a mechanical advantage of .125.
Energy
There are two main types of energy. They are Potential Energy and Kenetic Energy. Potential Energy is the energy that an object has at a certain height or in a gravitational field. Kenetic Energy is energy due to motion. For this project we found the Kenetic Energy of the marble in the cart going around the ferris wheel. For Potential Energy we also calculated the Potential Energy of the marble in the cart. To calculate the Kenetic Energy we multiplied 1/2 the mass of the ball by the velocity of the cart moving. The result was .05 joules. For Potential Energy we multiplied the mass of the ball by gravity by the distance top to bottom of where the cart goes. The result was 5.01 joules.
Reflection
For my first big Stem project I felt that things went fairly well overall. My group members were all cooperative and worked effectively together. At first we had a little trouble thinking of ideas but we worked together to brainstorm ideas for our project. We didn't have a main leader in our group. We all contributed and came up with ways to work through this project. The most challenging part of the project was taking an idea and actually building it. For example, we had the idea for the ferris wheel but when we first tried to make it it was tough to make a functional product. I really enjoyed going into the makers space and using tools to build the project. I learned a lot about how to calculate physics equations that I wasn't familiar with before. I was nervous going into the presentation but when it actually happened it went well and I was proud of our design.