Rube Goldberg Machine

Our Task

For this project, I was put in a group with Jacob, Zade, and Zane and we were faced with the task of distantly creating a themed Rube Goldberg machine with at least 15 steps, 5 simple machines, 4 energy transfers, and 3 elements of design. Our machine also had to complete a simple task at the end. For our theme we chose the steps of growing a flower. To complete this task it required lots of communication. On a daily basis we exchanged notes, thoughts, and gave each other constructive criticism on how to better our parts of the project. Below I have included our construction log. It shows what we completed and when on our 4 week time frame. 

Week 1: We focused on picking a theme, blueprinting, and a rough layout of our machine. We also decided on the materials we would use as well as specific time frame goals for the development process. 

Week 2: We acquired materials and steps 3-4, 6-7, and 11-12 of our sections were completed. 

Week 3: We focused on completing the machines steps, and afterwards we worked on the decoration of the machine. 

Week 4: We finalized the decoration and filmed each section. We then created our final presentation. 

The Final Product

Our group decided to base our Rube Goldberg machine on planting a flower and showing the steps it needs to thrive. We did this by assigning roles to each section of the machine which included planting a seed, watering it, giving it sunlight, pruning the plant, all leading to having a healthy flower pop up in the end. We also incorporated green throughout the machine to give the separate parts more of a flow.  

Simple Machines

In our project we included 5 simple machines. 

1. Lever. We used levers in all sections of our project. A lever is a rigid bar resting on a fulcrum and they are used to make work easier. In our project most levers had a effort(input force), a fulcrum, and a load(output force). One example was in Step 14 where the effort of the lever was a weight attached to one side of a pulley, the fulcrum was a cut pipe, allowing the lever to rotate, and the load was a ball being pushed down an inclined plane from the force. 

2. Wheel and Axle. A wheel and axle consists of a round disk(the wheel) with a rod(axle) through the center of it. The purpose of this simple machine is to make tasks easier by manipulating the force. We used a wheel and axle in Step 2. A gear rotates a lever because they have the same axle. 

3. Pulley. A pulley is a wheel on an axle that is designed to support movement and change of direction. We used multiple pulleys throughout our machine but one example was in Step 9. Due to the weight of the rocks falling into one side of the pulley, that pot gets pulled down while the other side moves upward because there is less weight. 

4. Inclined Plane. An inclined plane is a flat supporting surface tilted at a horizontal angle. We used inclined planes in all sections of our machine but one example is in Step 18, where a water bottle rolls down an inclined plane. 

5. Wedge. A wedge is usually triangular shaped and is used to separate two objects or portions of an object. We used a wedge in Step 13. Our wedge was connected to a pulley and when the weight was released, it pulled on the shears chopping a plant. 

Energy Transfers

In our project we had many energy transfers. Here are some examples:

1. KE → KE In step 18, the water bottle transfers all its kinetic energy into the wheel, making it spin.

2. KE → KE In step 8, the falling rocks transfer their kinetic energy (which came from gravitational potential energy) into the pot, pulling down on the pulley.

3. KE → KE In step 4, the flyswatter transfers its rotational kinetic energy into the fly, displacing it from its position atop the wire support.

4. PE → KE In step 16, each domino transfers its gravitational potential energy into the next domino.

Principles of Design

1.  Emphasis. Emphasis was used throughout our project to embolden our theme. We put emphasis on the color green, and therefore the ideas of plants and growth,  by incorporating green in the important parts of our machine.  

2. Balance. Balance was used in our machine because the machine’s tasks were split between each person roughly evenly.  In addition, within each person’s section no parts received too much focus and no parts were ignored.

3. Movement. Each section of the machine, and the machine as a whole, has a clear “direction” in which actions occur.  While the machine is not entirely linear, the elements are placed in a way that it is clear which mechanical elements lead to the next.

Calculations

Velocity: Velocity is the speed of an object moving in a particular direction. To calculate velocity, you divide the distance the object moved by the time it took to move that distance. For example, in Step 6, a marble rolls down an inclined plane so I calculated average velocity of that marble. I divided the change in distance (0.43m) by the change in time(0.93s) to get an average velocity of about 0.46m/s. 

Acceleration: Acceleration is the rate that velocity changes. To find acceleration of an object, you divide the change in velocity over the change in time. In Step 5, Zane calculated the acceleration of his ramp by dividing the velocity(1.77m/s) by the time(0.36s) to get a final acceleration of about 0.64m/s^2. 

Force: Force is the push or pull on an object that causes the velocity to change. To calculate force, you multiply mass and acceleration together. In Step 7, I calculated the force of the golf ball rolling down a ramp. I took the mass(0.046kg) and the acceleration(9.8m/s^2) and multiplied them together for the force of the golf ball(0.0138N).

Work: Work is the amount of energy that gets put into doing something. To find the work of an object, you multiply together the force and the change in distance. Whenever a ball is moving or anything is being accomplished, work is being done. I calculated the work of the golf ball in Step 7 by multiplying together the force of the golf ball(0.0138N) and the distance the ball traveled(0.2m) to get a final work of 0.00276J. 

Potential Energy: Potential energy is the energy an object has due to its position at a height or in a gravitational field. Potential energy is found by multiplying mass, acceleration due to gravity, and height. One example of potential energy in our machine is in step 16. Zade found the potential energy of dominoes by multiplying the mass(0.015kg), acceleration(9.8m/s^2), and the height(0.05m). The potential energy of these dominoes was 0.007J.

Kinetic Energy: Kinetic energy is energy due to motion so anything that moves is using kinetic energy. Potential energy and kinetic energy are ideally equal, but outside forces like friction and air resistance prevent that. To calculate kinetic energy, you multiply 1/2 to the mass and the velocity squared. I found the kinetic energy of the same marble from Step 6. I multiplied 1/2 by the mass(0.07kg) and the velocity squared(0.212) and got 0.00742 as the kinetic energy. 

Mechanical Advantage: Mechanical advantage(MA) is the ratio of a force that does useful work and force that is actually applied to the machine. These are shown in two different types of MA. There is ideal MA and real MA. Ideal MA calculates how much MA you would like to have in your machine while real MA calculates how mush there actually is. To find the ideal MA, you divide the force load over the force effort. To find the real MA, you divide the distance effort over the distance load. One example of when we found the ideal MA was in Step 17. Zade divided the distance effort(0.01m) by the distance load(0.01m) in which the product was 1. In Step 1, Zane found the real MA of lever by multiplying the MA of the lever(1) and the force effort(1.5) for a real MA of 1.5. 

Reflection

Overall, I think that my teammates and I did a really good job on our project and I am satisfied with my section of it. Although this project took lots of collaboration and communication, we got to be really creative and make an engaging and fun project. 

For this project, I think I did best in the collaboration aspect. Overall, my group got along really well which made working together an easy and pleasant experience. We all pitched ideas and decided on one that balanced out our strengths and weaknesses. I helped to divide the workload among the members and to make everyone's tasks clear. Our group communicated almost every day through zoom calls, email, and text so we could support each other and meet our time frame goals. Everyone was open to making changes through feedback and constructive criticism. 

Another aspect I think I exceeded in was work ethic and productivity. As soon as we created our timeline for finishing our project, I began to work so I could get on top of it. I ended up finishing a little before the rest of my group so I began working on my calculations for my section. Throughout the four weeks I stayed on top of my work and organized with my materials. I also helped keep my group on task and helped with what I could, considering we never got to physically work together.

On the other hand, I struggled with a few things during this project. One of my main weaknesses was leadership within my group. In the beginning of the project, we didn't know each other that well and it was hard to get the ball rolling. Looking back, I wish I had taken more initiative as that might have been beneficial to our team. Another challenge during the project was asking my group questions about their section of the project because I didn't want to seem nosy or controlling. Instead of getting help from my group I would go straight to the teacher or ask my close friends who are in the other STEM class. Saying this, my goals for the next collaborative project are to be a better leader and ask more questions within my group.