Our Project
|
A Rube Goldberg Machine is a mechanism that completes a simple task using complex mechanics. My team's Rube Goldberg Machine task was to ring a bell 3 times. There are three layers of mechanics that go off to complete the task. The first level is and input that pushes three golfballs to go down onto the second level and set off the levers. The levers then push over a large domino that starts 6 rows of smaller dominos. Those smaller dominos push an even tinier domino to go into a pulley system that lifts up a wedge,on the third level, and releases the car to roll down a ramp. The car pushes over dominos to hit the bell. The input also pushes a lever that knocks a golfball onto a ramp. The ramp has the ball fall into a spiral, on the third level, that speeds it up to hit the bell. On the second level, another tiny domino falls through a hole and into the large domino, on the third floor, that makes it fall. Once the large domino falls, on the third level, it knocks over a chain reaction of dominos to hit the bell a third time.
|
Physics Concepts
- Force- the push or pull on an object that causes a change in motion.
- Velocity- the rate of covered distance traveled in a direction.
- Acceleration- the rate of change in velocity.
- Impulse- how long and forcefully something is pushed "amount of shove."
- Momentum- the tendency for a moving objects to keep on moving.
- Work- the amount of energy put into an object.
- Potential Energy- the energy an object has due to where it is placed, height or proportion wise, in a gravitational field.
- Kinetic Energy- the energy due to motion.
- Mechanical advantage- how much easier a tool makes an object to move.
Calculation
Step One: Input pushes lever
5/8*5/8=25/64=MAideal
MAreal=Fload/Feffort
MAreal=1.2N/0.4N=3
Step Two: Levers push ball
F=ma
1.2N=0.0455kg(a)
a=26.4m/s^2
Step Three: Ball rolls down ramp
V=change in distance/change in time
V=0.85m/1.87s
Step Four: Ball gains speed going down screw
Beginning of spiral= 0m/0s=V=0m/s
End of spiral= 0.64m/0.64s=V=1m/s
Step Five: Ball hits bell
p=mv
p=0.0455kg(0.75m/s)
p=0.034Ns
KE=1/2mv^2
KE=1/2(0.0455kg)*0.75^2
KE=0.013J
Step Six: Input pushes 3 balls into levers
PEg=mgh
PEg=0.0455kg(9.8m/s^2)*0.1m
PEg=0.045J each(3 balls)=PEg=0.133J total
Step Seven: Levers push big domino
MAreal=Fload/Feffort
MA=0.55kg/0.1365kg
MA=-4
Step Eight: Dominos fall into pulleys
F=ma
F=0.05(9.8m/s^2) F=0.04kg(9.8m/s^2)
F=0.5N F=0.4N
Step Nine: Wedge is removed and car rolls down ramp
MAideal=d effort/d load PEg=mgh
MA=0.5m/0.1m PEg=0.055kg(9.8m/s^2)*0.1m
MAideal=5 PEg=0.015J
Step Ten: Massive domino tips over
PEg=mgh PEg=mgh
PEg=0.23kg(9.8m/s^2)*0.25 PEg=0.23kg(9.8m/s^2)*0.1m
PEg=0.56J PEg=0.015J
5/8*5/8=25/64=MAideal
MAreal=Fload/Feffort
MAreal=1.2N/0.4N=3
Step Two: Levers push ball
F=ma
1.2N=0.0455kg(a)
a=26.4m/s^2
Step Three: Ball rolls down ramp
V=change in distance/change in time
V=0.85m/1.87s
Step Four: Ball gains speed going down screw
Beginning of spiral= 0m/0s=V=0m/s
End of spiral= 0.64m/0.64s=V=1m/s
Step Five: Ball hits bell
p=mv
p=0.0455kg(0.75m/s)
p=0.034Ns
KE=1/2mv^2
KE=1/2(0.0455kg)*0.75^2
KE=0.013J
Step Six: Input pushes 3 balls into levers
PEg=mgh
PEg=0.0455kg(9.8m/s^2)*0.1m
PEg=0.045J each(3 balls)=PEg=0.133J total
Step Seven: Levers push big domino
MAreal=Fload/Feffort
MA=0.55kg/0.1365kg
MA=-4
Step Eight: Dominos fall into pulleys
F=ma
F=0.05(9.8m/s^2) F=0.04kg(9.8m/s^2)
F=0.5N F=0.4N
Step Nine: Wedge is removed and car rolls down ramp
MAideal=d effort/d load PEg=mgh
MA=0.5m/0.1m PEg=0.055kg(9.8m/s^2)*0.1m
MAideal=5 PEg=0.015J
Step Ten: Massive domino tips over
PEg=mgh PEg=mgh
PEg=0.23kg(9.8m/s^2)*0.25 PEg=0.23kg(9.8m/s^2)*0.1m
PEg=0.56J PEg=0.015J
Reflection
While building our Rube Goldberg, we had some problems. One of them included the K'nex ramp and spiral. The K'nex pieces took a while to get working because we had to find the right length of how long the ramp would have to be and how the spiral would get the ball rolling in a straight line towards the bell. We finally go the K'nex pieces working, after two build days. Another problem we had was getting the pulley system to lift up the wedge that kept the car from going down the ramp. The wedge was either to heavy or to light. In order o fix the problem, we added marbles in the cup that would catch the domino and lift up he wedge. Other than a couple difficulties, our project turned out amazingly well. The domino systems on the second level, turned out amazing and we had very little complications with those steps. Getting the right measurements for the boards and support beams were another thing that went well because we had a schematic that was up to scale on every thing we added. This was thanks to a computer program that we used for our schematic.
There were some different things that I learned, during this project. I learned how to opperate a chop saw and other different power tools. At the beginning of the whole project, I did not know anything about a lot of the power tools. For example, I didn't even know what the chop saw was called or how to use it. But towards the end of the building days, I would be helping others with it. I also learned how to work with different personalities. This was an amazing experience that would benefit me later in life.
I did have some things that I could have done better and will continue to work on. One of them being that I should work on making sure that we all divide the work evenly. The second being that I should make sure I have better leadership skills and take charge once in a while.
There were some different things that I learned, during this project. I learned how to opperate a chop saw and other different power tools. At the beginning of the whole project, I did not know anything about a lot of the power tools. For example, I didn't even know what the chop saw was called or how to use it. But towards the end of the building days, I would be helping others with it. I also learned how to work with different personalities. This was an amazing experience that would benefit me later in life.
I did have some things that I could have done better and will continue to work on. One of them being that I should work on making sure that we all divide the work evenly. The second being that I should make sure I have better leadership skills and take charge once in a while.