Friday, October 29, 2010

Final Project Ideas!!

SO the time has come to think about ideas for our final project! YAY!
1. SUPER interactive robot--I was thinking it would be cute if it responded in some way to everything around it. For example, if someone walked by, it would say 'Hi!' and if they responded, it would maybe do a little dance.

2. Airplane--A moderately sized airplane on a stick that responded to air. If you blew on it, the propeller would turn on, it would make whirring airplane noises, and fly around.

My Favorite Idea:
3. Racing cars!--I would make 2 simple carts and wireless controllers or joysticks, and people could race them on an obstacle course. Another girl in the class really liked this idea, and we started talking about different things we could do based off of racing cars. She suggested we try and duplicate a Mario Cart challenge: balloons (you know, each player has 3 balloons and loose a balloon each time they hit something or are hit by another car). It would be difficult to find a way to make the balloons disappear after the car was hit. Perhaps we could reel in the balloons and pop them on a little needle. Or release them so they float out of the way. If I do this idea, we'll have to experiment with different methods.

We'll see where these ideas takes me...

Friday, October 8, 2010

We're switching over to the dark side... not

Onto the next challenge! This one was tough, really tough. Mostly because of mechanical problems. For this challenge we had to make our robot find and follow a moving light. We used different sensors, which detected light and brightness level. They looked like this:
In order to make them more precise, we put 'blinders' around the sensors. This helped narrow the beam of light hitting them.
And so we settled in on how to crack this case. Every program we tried failed, sometimes the robot would turn away from the light instead of towards it, and we couldn't figure out why until other girls in the class suggested we check  our resistors, because that would affect the sensitivity of the sensors. Turns out our resistors were different, and we had no problems after we changed them. Our program worked just as it should.
Our program went like this: the robot starts by turning until it finds the light source (one of the sensors reads a certain number meaning that the light is great enough to assume that the robot is directly facing it). Once it has found the light, it uses the numbers from the light sensors to continue finding the light. If the right sensor drops below a certain number, it means that the light has moved to the left, and so the robot turns left. You can see how having different resistors would throw the program off: the numbers reading from the sensors made no sense because there was a huge discrepancy, which of course made finding a number for when the sensors were facing the light (when the numbers from the sensors should have been pretty equal) impossible.

Thursday, October 7, 2010

Our third challenge was to write a program for our robot to follow a random black line. We graduated from the simple Cricket program to a more complex version called RDS. The new program allows for more complicated actions.
For this third challenge we attached sensors that detected changes in color and brightness to the front of the car, one on each side (sensor 1 on the right, and 2 on the left). The sensors look like this:

Our thinking was to start with one sensor on each side of the line and have the car swerve left and right to find the line. This ended up being a good idea, and our robot worked well!

Unfortunately, our professor was less than impressed. Our next challenge was to make our robot able to pass a sobriety test. This was a little more complicated, but after a little bit of thinking we came up with this program:

Now, our robot goes straight until it finds a turn in the line, at which point it turns in the direction of the side with the sensor that detected the change in light as it found the black line. Then it goes straight again. Any policeman would be proud of this safe, sober driver!

Tuesday, September 14, 2010

Day 2: Improving our Kinetic Sculpture

          Today we expanded upon the sculpture we made on Day 1 using "edge" and "level" triggered logic. Level triggered logic means that an action will run unless there is a change in circumstance. For example, a motor will run one way until a button is pressed, and then it will go in reverse as long as the button is held down. Edge triggered logic means that as soon as the button is pressed the motor will reverse, and holding down or letting go of the button won't change the action--one must unpress the button and press it again to change the action.
          Above is a video of our train. Two actions are occurring at the same time: 1) The light is changing from orange to light yellow to dark red to purple as we change the light hitting a light sensor, simulating the change in light over a 24 hour period (dawn, day, evening, and night). 2) The motor doesn't start until a button is pressed, and then as we keep pressing the button it reverses, stops, and then starts up again. Both of these actions are edge triggered--they occur as soon as we press the button or change the light over the sensor.
          The first image is the program we wrote for the changing lights. One can clearly see the progression from daylight to night to dawn, which will repeat "forever" as long as we keep the program running. We named this program "DY&Nt." Similarly, our second program, entitled "SqW," or "Squeaky Wheels," which controls the motion of the motor, is set to run "forever."
          Put together, the programs tell a nice, little tale of a female conductor who starts her train in the morning, rides around during the day, reverses back home in the evening, and stops at night.

Tuesday, September 7, 2010

Day 1: Our first engine!

It's the first day of class and we've built our first engine. Say hello to Chugga! He responds to changes in light (he slightly on the dark side): when the light sensor is covered, he moves, but when it senses light, he stops.