User:Zbennett/enes100/My Work (Rube Goldberg 2)

Write problem/project Goal
Create a Rube Goldberg machine out of printer parts, that effectively demonstrates how printer parts move and function together.

My First Task
Figure out how to program solenoid with the arduino to activate, and impact the chimes.

Summary of actual work over first weekend
I figured out that the solenoids would have to be powered by a PSU, because the arduinos cannot put out enough voltage to cause the solenoids to activate.

Week1 Narrative
In order to cause the solenoids to activate in a timed manner, with any level of precision, I'll need to devise a mechanism that turns the PSU on and off rather quickly. Because this may damage the PSU, I realized that I can make a circuit from the PSU to the solenoid that has a switch in it. This switch can be controlled by the arduino, which CAN be precisely timed. This way, the arduino can complete and break the circuit in perfect timing, causing the solenoid to impact the chime in an audibly pleasing manner, rather than a spastic mess. Here is a video, showing what the solenoid looks like when impacting the chime.

My Second Task
I will prepare the stand to bring in.

Summary of actual work over second weekend
I made final modifications to the stand to prepare to bring the stand for the rube goldberg machine in.

Week2 Narrative
I realized that, due to the use of scrap pieces of wood, the stand was approximately 8 feet tall. I used a pencil to mark an appropriate length, and cut them with a hand saw.

My Third task
Figure out why one of the solenoids is maintaining its magnetic field.

Summary of actual work over third weekend
After attaching both solenoids to the board and wiring them into the power supply, I found that one of the solenoids seems to "stick" after the power source has been deactivated.

Week3 Narrative
I wired both the solenoids into the power supply, and found that one if them experiences residual magnetism after the current is no longer running through the solenoid. In the video, this is clearly demonstrated by the solenoid on the right. Both of the solenoids are connected in a parallel circuit to the power supply, and both are unplugged at the exact same time. Through experimentation, I found that the longer the current runs through the solenoid, the longer it maintains the magnetic field after the current is cut. Inversely, when the current is run through the solenoid in very quick, short bursts, it functions identically to the one on the left. While taking a break from this problem to let it process in my brain, I attached the laser printer motor to the printer board that was previously attached to the plywood. It functions off of a 5V current.

My Fourth task
Mount the entire device on wheels.

Summary of actual work over fourth weekend
I mounted the Rube Goldberg machine on wheels, and encountered a few problems while doing so. I also attempted to replace the painters tape belt that was attaching the various printer boards together with other materials.

Week4 Narrative
In order to attach the wheels to the board, I had to drill holes in the bottom of the stand. Since the bottom of the stand had no large flat spots on it where I could drill holes for the wheels, I had to cut four short lengths of 2X4, and attach those to the bottom of the stand, so then I could drill holes in those. After drilling the holes and inserting the wheels (the holes were ever so slightly smaller than the wheel's axle to assure a tight fit), I inserted the wheels and gave it a push. The stand moved just fine, but I noticed the legs of the stand wobbled severely when moving across the room. I then measured and cut another length of 2X4 to use as a cross-brace between the two legs of the stand. I first tried to screw this onto the legs of the stand, but realized the screws were too short. I then attempted to countersink the screws which worked until I applied pressure to the cross-brace, which caused the screws to strip out the wood, and fall off. I ended up just hammering two long nails into each leg which held the cross-brace on securely. As an aside, I attempted to replace the painter's tape belt which was connecting the printer boards together with another material. I decided to use string with knots tied in it, to act like the teeth of a rubber belt that was designed to go with the system, but was too short to serve our purpose. The knots ended up getting caught on the metal parts of the printer board, so I decided to try just using plain string. This actually worked the best, seeing as there was no crunching sound of tape, and no sticking of tape which slowed the system down. Attached is a photo of the entire assembly mounted on the stand. I also created this tutorial on how to countersink a screw.

Complete Team Page
Fill out the Team Form (should have already copied the form, created the team page, linked to it and started filling it out).