My Rube goldberg machine
The goal of our Rube Goldberg machine was to cut fruit. Mainly pears (VIVA LA RESISTANCE) (Parie Antonette) As you can see some pears are just too hard...
THe Plan
The first step of any Rube Goldberg machine is the plan or schematics we wrote out the plan on a piece of paper and decided to cut fruit for the entertainment of the crowd and play an important part in the French Revolution. I (Leo) brought in the guillotine that I made at home with the help of my uncle and father. The rest of the machine was made during class working hours.
Constructing the MASTERPIECE
On day one I brought in my guillotine and we began to build supports for the large section of plywood that would be our canvass. We did this by placing three two by fours on the base facing outward we screwed these in and we were able to stand it up. After this step was completed we started with our inclined plane we used a V indented small section of cabinet wood. Originally we had planned to nail it... no this would make nail heads obstruct the path of the marble then glue.. no such luck. Then we found that we could safely and securely position it on top of the nails and the build was back on.
On day 2 and 3 we constructed our pulley system. This took quite a while and a lot of adjusting to get the weight right and for the cup of the pulley to knock into the marble on the second inclined plane which was constructed during this time period. We added a quarter to keep a weight that could knock the marble into motion. We had to add in an indentation on the second inclined plane to keep the marble stationary for its planned collision. Even after these days of tweaking it still only worked 90% of the time the cup would sometimes land in front or on top of the marble pinning it down.
On days 4 and 5 the "Guillo-team" (us) started to connect the funnel, which acted like a screw to the end of step three inclined plane this dropped the marble into a lever that Eric and I built. This lever's two sides did different things one side had an up facing cup to catch the marble and the other had a downward facing flat piece of wood. The cup caught the marble which acted as a counter weight to raise the wood that released the lacrosse ball to activate the guillotine (more on that later). The ball in the cup rotated fully down and rolled down to the next inclined plane (more on that later as well).
On days 6 and 7 we made the ramp to lead the lacrosse ball to the clothespin that held the rope and ring to the guillotine. We added rails to keep the ball from escaping our death trap. We also did lots of tweaking to the projects already finished parts.
On the last few days we added the inclined plane that leads to the back and fourth inclined plane matrix that dropped a ball on a space bar to create a cheering noise. We tweaked everything in some small way and then we began to work on our aesthetics and our final equations. In the end the machine worked 89% percent of the time but it was still a great success.
On day 2 and 3 we constructed our pulley system. This took quite a while and a lot of adjusting to get the weight right and for the cup of the pulley to knock into the marble on the second inclined plane which was constructed during this time period. We added a quarter to keep a weight that could knock the marble into motion. We had to add in an indentation on the second inclined plane to keep the marble stationary for its planned collision. Even after these days of tweaking it still only worked 90% of the time the cup would sometimes land in front or on top of the marble pinning it down.
On days 4 and 5 the "Guillo-team" (us) started to connect the funnel, which acted like a screw to the end of step three inclined plane this dropped the marble into a lever that Eric and I built. This lever's two sides did different things one side had an up facing cup to catch the marble and the other had a downward facing flat piece of wood. The cup caught the marble which acted as a counter weight to raise the wood that released the lacrosse ball to activate the guillotine (more on that later). The ball in the cup rotated fully down and rolled down to the next inclined plane (more on that later as well).
On days 6 and 7 we made the ramp to lead the lacrosse ball to the clothespin that held the rope and ring to the guillotine. We added rails to keep the ball from escaping our death trap. We also did lots of tweaking to the projects already finished parts.
On the last few days we added the inclined plane that leads to the back and fourth inclined plane matrix that dropped a ball on a space bar to create a cheering noise. We tweaked everything in some small way and then we began to work on our aesthetics and our final equations. In the end the machine worked 89% percent of the time but it was still a great success.
The steps And behind the scenes calculations
Step 1: Straw Ben blew through a 19 cm straw to get the ball rolling... literally.
Step 2: Inclined Plane. The marble rolls down the inclined plane. We calculated the velocity of the marble by dividing the length and the time the ball took to roll down the plane. We divided .4 meters by .22 seconds and obtained a velocity of 1.82 m/s.
Step 3: Pulley. The ball rolls into the cup making the cup fall and hit the second ball. We measured the force of the pulley by finding the pulley's mass which was .162 kg which transfers into .162 N of force.
Step 4: Inclined Plane. The marble spins around the funnel as if it where a screw. For this one we calculated the mechanical advantage which was 5.14 by dividing the length by the height.
Step 5: Funnel/Screw. The marble rotates around the inside of the funnel making it a screw (technically). On this step our group calculated the mechanical advantage that was 5.14 by dividing the length by the height.
Step 6: Lever. The lever releases the lacrosse ball onto the inclined plane that leads to the guillotine release clip and also is directed to the second end result. In this simple machine we calculated the distance from which the weight is applied 19 cm from the distance the weight has moved 16 cm we divided 19 cm by 16 cm giving us an mechanical advantage of 1.187.
Step 7: Inclined plane (to the guillotine). The ball follows inclined plane to the clothespin release mechanism .For this step our group decided to find the force it takes to push the clothespin lever. Using the formula of F=MA (force=mass x acceleration) The ball weighed 156.2 grams, it took half a second for the ball to strike the clothespin, length of the plane is 45 cm and height is 12 cm. F=156.2 x 9.8 which leads to F=1530.76 N.
Step 8: Inclined Plane (to the cheering effect). The marble from the funnel lands in the cup on the lever dropping it onto this inclined plane. We needed to find the potential energy (PE) of this step. We found that the plane was 10 cm long and 1.5 high. We used the formula PE=mgh using data we already knew. PE=.0162 x 9.8 m/s x .015 which equals a PE of .0023814 Joules.
Step 9: The Switchback Inclined Planes. Our marble enters a series of inclined planes that drop back onto each other like a zigzag. We calculated these zigzag planes as a single physics entity which was about 11 cm long and 3 cm of width. Then we found the mechanical advantage by dividing 11/3 which gave us an MA of 3.67.
Step 10: Tube. We had a tube at the end of that zigzag section the tube was 17 cm tall and calculated the force of the marble on the space bar using F=MA F=.0162 x 9.8 we got F=.16 Newtons of force.
Step 11: The Guillotines Pulley. Returning to the now familiar guillotine area of the Rube Goldberg the clip is released by the ball which releases the pulley.We calculated the pulley to have a force of 10 newtons (N)and a MA of 1.
Step 12: The Guillotine Wedge/Blade. Our step 11 pulley releases the wedge which falls down on the condemned criminal or in our case tyrant. Our group calculated the mechanical advantage of the wedge to have 2200 MA. We learned this by measuring the thickness of the sheet metal blade .00005 m was the thickness, and the length was .11 m. We divided the length by the width of the blade and got a MA of 2200.
Step 2: Inclined Plane. The marble rolls down the inclined plane. We calculated the velocity of the marble by dividing the length and the time the ball took to roll down the plane. We divided .4 meters by .22 seconds and obtained a velocity of 1.82 m/s.
Step 3: Pulley. The ball rolls into the cup making the cup fall and hit the second ball. We measured the force of the pulley by finding the pulley's mass which was .162 kg which transfers into .162 N of force.
Step 4: Inclined Plane. The marble spins around the funnel as if it where a screw. For this one we calculated the mechanical advantage which was 5.14 by dividing the length by the height.
Step 5: Funnel/Screw. The marble rotates around the inside of the funnel making it a screw (technically). On this step our group calculated the mechanical advantage that was 5.14 by dividing the length by the height.
Step 6: Lever. The lever releases the lacrosse ball onto the inclined plane that leads to the guillotine release clip and also is directed to the second end result. In this simple machine we calculated the distance from which the weight is applied 19 cm from the distance the weight has moved 16 cm we divided 19 cm by 16 cm giving us an mechanical advantage of 1.187.
Step 7: Inclined plane (to the guillotine). The ball follows inclined plane to the clothespin release mechanism .For this step our group decided to find the force it takes to push the clothespin lever. Using the formula of F=MA (force=mass x acceleration) The ball weighed 156.2 grams, it took half a second for the ball to strike the clothespin, length of the plane is 45 cm and height is 12 cm. F=156.2 x 9.8 which leads to F=1530.76 N.
Step 8: Inclined Plane (to the cheering effect). The marble from the funnel lands in the cup on the lever dropping it onto this inclined plane. We needed to find the potential energy (PE) of this step. We found that the plane was 10 cm long and 1.5 high. We used the formula PE=mgh using data we already knew. PE=.0162 x 9.8 m/s x .015 which equals a PE of .0023814 Joules.
Step 9: The Switchback Inclined Planes. Our marble enters a series of inclined planes that drop back onto each other like a zigzag. We calculated these zigzag planes as a single physics entity which was about 11 cm long and 3 cm of width. Then we found the mechanical advantage by dividing 11/3 which gave us an MA of 3.67.
Step 10: Tube. We had a tube at the end of that zigzag section the tube was 17 cm tall and calculated the force of the marble on the space bar using F=MA F=.0162 x 9.8 we got F=.16 Newtons of force.
Step 11: The Guillotines Pulley. Returning to the now familiar guillotine area of the Rube Goldberg the clip is released by the ball which releases the pulley.We calculated the pulley to have a force of 10 newtons (N)and a MA of 1.
Step 12: The Guillotine Wedge/Blade. Our step 11 pulley releases the wedge which falls down on the condemned criminal or in our case tyrant. Our group calculated the mechanical advantage of the wedge to have 2200 MA. We learned this by measuring the thickness of the sheet metal blade .00005 m was the thickness, and the length was .11 m. We divided the length by the width of the blade and got a MA of 2200.
Reflection
During our Rube Goldberg project many things happened and i would like (and am required to) reflect on. All the while we were working on our project we all got distracted we were used to our project so everyone else's projects were much more interesting. "Hold on guys I'm gonna go check out their thing be right back..." This was relatively detrimental and at times we had no one working on the project and it took a while to get everyone refocused. Another thing I'd like to mention, everyone wanted to play with the guillotine... EVERYONE it was also very annoying that people continued to ask us to cut things. When we asked for things to cut it was different right??? Nope we always were unnecessarily slicing fruit and vegetables, we were like a food bar.
There were good things too when everyone was super focused and we got things done quickly and efficiently we were like a well oiled machine painting, nailing, calculating we got lots done then. Another high point or "peak" was having the guillotine on the first day it meant we could tweak it to work every time because we spent the most time with it. Overall it was a great experience and we worked pretty well I learned a lot and I'm sure everyone else did too.
There were good things too when everyone was super focused and we got things done quickly and efficiently we were like a well oiled machine painting, nailing, calculating we got lots done then. Another high point or "peak" was having the guillotine on the first day it meant we could tweak it to work every time because we spent the most time with it. Overall it was a great experience and we worked pretty well I learned a lot and I'm sure everyone else did too.