Rube Goldberg Machine

Hi!

These photos show the Rube Goldberg machine my teammates and I constructed for the Bay Area Science Olympiad. I was the chief architect of the project. The machine took us over 50 hours to build and was accomplished in the span of two weeks! The feat required much dedication and effort from all teammates.

There were 10 required steps. The sequence of steps was unrestricted, except that the Rube Goldberg machine had to be triggered by a golf ball hitting a mousetrap and ended with the raising of a flag 30 centimeters above all other parts of the machine.

Step 1: Starting Task- Drop golf ball into an egg holder that triggers the mouse trap.

Step 2: The string attached to the mousetrap is pulled and causes a needle to pop a black balloon, allowing a flashlight to shine to the other end of a tunnel.

Step 3: Light from the flashlight activates a photosensor that will activate a battery to power a motor. The motor pulls a copper wire to connect an electrical circuit.

Step 4: Connection of the electrical circuit causes an electrical wire to heat up and melt a mono-filament wire. The mono-filament wire breaks, releasing a hammer.

Step 5: The hammer pushes a football into a bike pump needle, activating the pneumatic system. The rubber hand glove inflates and breaks an electric circuit.

Step 6: Breaking of the electric circuit leads to deactivation of an electromagnet, which drops a nail, thereby connecting another electric circuit.

Step 7: Connection of the electric circuit causes a motor to turn a shaft to move a battery for over 10 seconds. The new position of the battery connects another electric circuit.

Step 8: Connection of the electric circuit allows a battery to pull a golf ball up. Its new position connects another electric circuit.

Step 9: Connection of the electric circuit powers a fan to blow a copper cylinder down a slope, leading to connection of another electric circuit.

Step 10: Final task- Connection of the electric circuit allows a set of batteries to power a motor to raise a flag 30 centimeters above all other parts of the machine.

We came upon many problems while building the machine. We used innovative techniques to solve these problems.

In Step 3, we needed to use a photosensor. Since high-power photosensitive transistors were quite expensive, I made a switching circuit which used a photosensitive resistor, or photocell, and multiple low-cost NPN transistors in parallel. When I shined a flashlight on the photocell, it turned the transistors on, which supplied power to a molybdenum wire heater.

In Step 6, we needed to incorporate an electromagnet. I made the electromagnet using half of a transformer from an old cell phone charger.

In Step 10, we had a great deal of trouble trying to raise the flag 30 centimeters above all other structures due to space constraints. We solved this problem by combining both lever and pulley mechanisms in the flag-raising design.