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"All Men Are Created Equal"

Project by Laura M. Boudreau

Beginning Thoughts:

When I first began to think about this project, I questioned what my culture was. I even questioned what "culture" meant, as in today's society it seems to have become a part of everyday vocabulary but no one ever stops to really think about its definition. Then the more I thought about it, the more I realized that I felt almost without a culture. Certain ethnic and religious groups in America have specific customs and traditions that help define their cultures--many Chinese-Americans celebrate the New Year, Jewish students here at Tufts are prominent in Hillel, and the list continues. And then one day someone asked me, "What are you?", referring to the countries of origins of my ancestors. And I rattled, as I had since I was little, "I am one-half Irish and one-half French". Later, I thought about my automatic response--it certainly wasn't unlike the responses other people would give if asked the same question. And I wondered, why doesn't anyone say they are American? In England, ask someone who was born there "what they are" and the answer will be "English!" no matter where their genes began. I decided then that I would focus my project on an American value, and I would try to create a project that would cause reflection and spark discussion.

I began by thinking about what characterizes America--what values could I possibly illustrate with LEGOS? I thought about the words, "Life, liberty and the pursuit of happiness". I tried to think of a way to incorporate those very abstract ideas into something tangible, but I was stumped. I then thought of the other famous words, "All men are created equal" and immediate connected equal with the symbolic scales. My project idea was then born--I was going to create a scale that no matter the "weight" (weights with pictures of people of different ethnicities) it would always remain in balance. The trick was to actually be able to defy gravity--before I started to build anything, I drew a quick sketch of my idea:

I thought that I would have four touch-sensors--two would indicate when the scale was level and the other two would indicate which direction the scale had tipped. The program would wait for the two center sensors (1) to be released, and then once either of the two bottom sensors (2 or 3) were pressed, the motor would engage until the center sensors were pressed, meaning the scale was back at center. Based on that information, the motor would turn either forward or backward to wind the string and pull the scale back to center.

Design/Construction Process:

Step 1. I first created a simple scale using a pulley system--if one side was pushed down, the other side would go up. I had to use two green beams on either side on the bottom in order to stabilize the center beam. With only one green beam, the center beam was too wobbly.
Step 2. I then attempted to attach one motor so that it would be able to counterbalance the weights. I first tried to attach the bottom strings to a pulley which would be attached to the crank arm of the motor. That didn't work--the string wouldn't stay in the groove of the pulley. I then used a connector, thinking I could tape the string to it, because I knew I had to have it actually attached to the mechanism it was going to coil onto. That didn't work either--the string slipped through the tape. What I need was a LEGO piece I could tie the string onto.
Step 3. I found the piece--these little connectors with a slit down them. I don't think they are usually used for this, but I was desperate and had to be creative. It works ok--often the string doesn't wind around it perfectly, but it is the best I can do for now. But, now that the strings are permanently attached, I have to use two motors. This is getting tricky now...
Step 4. After I had the two motors connected, I had to have a way to tell them to turn on and off. I used four touch sensors like I first thought I would--two to indicate where center was and two to indicate which way the scale had tipped. I had this working, but not as well as I hoped. The scale platforms often got stuck on the sensors or weren't stable enough to push them back in. If they tipped too far, they got stuck on the top. Time for a new plan.
Step 5. I decided to switch to light sensors so that the scale platforms don't keep getting stuck on them. I first tried using a black piece of paper attached to the back of the platform, but there wasn't enough difference between the readings for the room light and for the paper. So I switched to white paper which works much better. I learned something new at this step--I have two light sensors stacked onto Port 1 of the RCX, since they have the same function and I need the other two input slots. The RCX actually adds the two values so that the light readings of Port 1 were double what I thought they were going to be. I had to take this into account when programming the "wait-fors" because it was opposite what it should have been.
  Step 6. I finished the beginning programming (see below). I still have to create the "weight people" and do more testing and tweaking...but I am off to a good start...

Programming:

This what I have for my program so far: