Theme
Medieval Madness
What is a Rube Goldberg Machine?
A Rube Goldberg machine is a contraption or invention that is intentionally over-engineered to perform a relatively simple task the most complicated fashion possible, generally including a chain reaction. In our case, we made a Rube Goldberg machine that launches a catapult. In this project, we were supposed to build a Rube Goldberg machine with a theme. For example, my team's main theme was "Medieval Madness".
The project was meant as an engineering exorcise that tested ability to work out certain problems and our creative and critical thinking. It also tested our ability to calculate the physics behind each step. This was a task that required teamwork and communication, as well as good time management.
The project was meant as an engineering exorcise that tested ability to work out certain problems and our creative and critical thinking. It also tested our ability to calculate the physics behind each step. This was a task that required teamwork and communication, as well as good time management.
Concepts
Our main concepts were acceleration and velocity, which we were required to find for the beginning and end of our Rube Goldberg machine.
As for the theme concepts, aside from the obvious(the catapult and the execution), was the swing, which represented a battering ram used for sieges. The dominoes represent the gates or walls of a palace being toppled down.
As for the theme concepts, aside from the obvious(the catapult and the execution), was the swing, which represented a battering ram used for sieges. The dominoes represent the gates or walls of a palace being toppled down.
Steps and Calculations
Step 1: We decapitate the subject.
Step 2: The "head" rolls down the ramp.
Step 3: The marble drops and rolls down another inclined plane and drops again.
Step 4: The marble triggers the dominoes
Step 5: The dominoes trigger the ram.
Step 6: The ram triggers the dominoes
Step 7: The dominoes trigger the pully's counter-weight
Step 8: The pully releases the metal wheel.
Step 9: The wheel rolls down and pushes a wedged block of wood.
Step 10: The wedged wood falls and triggers the trigger for the catapult.
Step 11: The catapult fires.
Calculations
Step 1: Force of wedge=Force of ball
.028kg*(9.8m/s2÷8×)=.028kg*1.225m/s2= .034 N
Step 2: Avg. Velocity of marble=
1.01m/1.63s=0.62 m/s
Step 3:Change in PE of marble=
0.03kg*9.8m/s2*1.03m-0.03kg*9.8m/s2*0.95m=0.29J-0.26J=0.03 J
Step 4:Avg. Velocity of marble=
1.08m/1.87s=0.58 m/s
Step 5:Change in PE of marble=
0.03kg*9.8m/s2*0.81-0.03*9.8*0.66= 0.22J-0.18J=0.04 J
Step 6: Toppling: When the domino’s center of mass goes outside the base, it’s called toppling.
Step 7:The swinging battering ram gets Kinetic Energy from the last domino of the first domino set and transfers it to the first domino of the last domino set.
Step 8:Toppling: When the domino’s center of mass goes outside the base, it’s called toppling.
Step 9:MA=1x (Wraps the pulley once)
Step 10:Avg. Velocity of wheel= 0.27m/0.99s=0.27 m/s
Step 11:Avg. Velocity of wheel= 0.27m/0.42s=0.64 m/s
Step 12:Force of wheel=4.5 N (Found using Spring Balance)
Step 13:Force of tennis ball due to gravity on catapult arm= 0.06g*9.8m/s2=0.56N
What do These Symbols Mean?
MA= Mechanical Advantage= How much easier it is to move an object
N= Newtons= The unit of force
PE= Potential Energy= Energy that an object has due it's position
KE=Kinetic Energy= Energy that an object has due it's motion
Force= The push or pull of an object
Velocity= The rate of covered distance in one direction.
Δ= Delta= Change
N= Newtons= The unit of force
PE= Potential Energy= Energy that an object has due it's position
KE=Kinetic Energy= Energy that an object has due it's motion
Force= The push or pull of an object
Velocity= The rate of covered distance in one direction.
Δ= Delta= Change
Art and Design Principles
Balance: The metal wheel is balancing on its edge.
Contrast: The silver ball stands out from the rest of the machine, because it represents the renaissance shining through the Middle Ages.
Emphasis: The catapult.
Patterns: We use three ramps, and three platforms.
Proportion: We start from a silver ball and eventually we eventually end with a large capault triggered by a large piece of wood.
Rhythm: Rhythm is showed throughout the entire machine. As the machine goes in a downward descent, we have a back and forth movement.
Unity/Harmony: Majority of the materials used in our project are made out wood.
Variety: We have a variety of trigger mechanisms and simple machines.
Visual Movement: THE ENTIRE MACHINE!
Contrast: The silver ball stands out from the rest of the machine, because it represents the renaissance shining through the Middle Ages.
Emphasis: The catapult.
Patterns: We use three ramps, and three platforms.
Proportion: We start from a silver ball and eventually we eventually end with a large capault triggered by a large piece of wood.
Rhythm: Rhythm is showed throughout the entire machine. As the machine goes in a downward descent, we have a back and forth movement.
Unity/Harmony: Majority of the materials used in our project are made out wood.
Variety: We have a variety of trigger mechanisms and simple machines.
Visual Movement: THE ENTIRE MACHINE!
Peaks and Pits reflection
Peaks |
Pits |
I kept my team good on time. In fact, we started a day ahead of schedule.
I learned that plans are not set in stone, they can be revised. I believe the blue prints can prove that. I learned that even though it would be faster to DIY, it is better to have a team to discuss plans and bounce ideas off each other. This was just a test run, I still have time to work on certain things that I lack. |
I was unempathetic to my teammates.
I did not leave any room for error in the project. Meaning, if a marble was slightly slower, .it could not trigger the next step. I was kind of the dictator of the team. Granted I did listen to their Ideas, but I was hellbent and stubborn. I did not prepare for error. i.e. I did not bring backup rubber bands, dominoes, marbles, ect. |