Compound Machine
Design Brief
Gantt Chart
Decision Matrix
Brainstorming list
Our first idea was to have a Pulley, Gears, Lever.
Our second idea was to have a Pulley, Inclined Plane, Lever (what we went with).
Our third idea was to have a Lever, Gears, Inclined Plane.
Our second idea was to have a Pulley, Inclined Plane, Lever (what we went with).
Our third idea was to have a Lever, Gears, Inclined Plane.
Preliminary Sketches
Finally Sketch with Annotations
Building process, Testing results, and Modifications
To build our machine we used pieces of metal, screws and nuts to build a ramp and platform. A big wheel would sit on top of the platform on a lever and the lever would be lifted up by a pulley system to make the big wheel go down the inclined plane and hit a text book, which would then land on the stapler and staple the paper. However, using a textbook was not allowed because it was not part of Mrs. Harlan's materials, so we couldn't use a textbook. Since we couldn't use a text book we had increased the height of the platform and steepness of the slope of the inclined plane, so the big wheel would come down with more force and speed to staple the paper. After making these changes we tested out our compound machine and it worked so we kept the compound machine the same except for a few other small change to increase the probability of it working every time. We modified our machine by removing the textbook and increasing the height and slope of the inclined plane.
Final design picture
Final calculations
Conclusion questions
1. For which mechanism was it easiest to determine the mechanical advantage or drive ratio? Why was it the easiest?
The pulley was the easiest to determine because all I had to do was count the number of strands going the opposite direction of the resistance force, and our compound machine only one strand.
2. For which mechanism was it the most difficult to determine the mechanical advantage or drive ratio? Why was it the most difficult?
The simple machine that was the hardest to find out the MA was the lever because it was very hard to figure out what numbers to plug into the equation.
3. At what value would you estimate the input and output forces of your compound machine? How did you arrive at your estimated values?
For one pound of input, the compound machine produced 3.75 pounds of output. Our group figured this out by determining the overall MA of the compound machine.
4. What modifications could you make to your compound machine to make it more mechanically efficient?
We could of add another pulleys because the machine would than have a smaller input force and get the same amount of output force. If there was two opposing strands on the pulley instead of one strand then the MA of the pulley would become two, which would then make the overall MA 7.5. This would make the input force get cut in half. Also we could of made the railing go al the way up so the wheel would stay in the same line and not have a chance of getting stuck.
The pulley was the easiest to determine because all I had to do was count the number of strands going the opposite direction of the resistance force, and our compound machine only one strand.
2. For which mechanism was it the most difficult to determine the mechanical advantage or drive ratio? Why was it the most difficult?
The simple machine that was the hardest to find out the MA was the lever because it was very hard to figure out what numbers to plug into the equation.
3. At what value would you estimate the input and output forces of your compound machine? How did you arrive at your estimated values?
For one pound of input, the compound machine produced 3.75 pounds of output. Our group figured this out by determining the overall MA of the compound machine.
4. What modifications could you make to your compound machine to make it more mechanically efficient?
We could of add another pulleys because the machine would than have a smaller input force and get the same amount of output force. If there was two opposing strands on the pulley instead of one strand then the MA of the pulley would become two, which would then make the overall MA 7.5. This would make the input force get cut in half. Also we could of made the railing go al the way up so the wheel would stay in the same line and not have a chance of getting stuck.