Braitenberg Vehicles – v1.0

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For our Braitenberg Vehicles project, we were to create Braitenberg's first four cars. The basic idea behind these vehicles is that each vehicle has a set of sensors and motors. The sensors cause the motors to move: either speed up or slow down. By connecting different sensors to different motors, you can cause the cars to have different movements.





Math: Math!!

Although I usually start with the visual side of these projects, this time I wanted to first figure out how the vehicles would move on-screen.

Getting Around
The first car, Getting Around, was pretty simple. The light intensity, taken from the sensor, directly correlates to the y-position of the car. At this point, I threw together some basic graphics using the handy-dandy StdDraw library and a few JPEGs. You can see the final Getting Around car to the right.

Implementing two motors and sensors, however, was much more challenging. At first, I was trying to calculate the distance each motor would travel with a bunch of geometry. Needless to say, that didn't get me very far. I decided to opt for the much simpler option of having the car travel forward, and the angle that it travels at varies. Now, I could easily take the difference of the intensities from the two sensors and multiply that by a constant to get the angle that the car should change.

Problems with Power

So, all seemed good until I got up and unplugged my computer. Suddenly, all of the vehicles slowed down! At first, I couldn't figure out what was causing the slowdown. However, with the help of my teacher, we figured out that my computer went into power-saving mode when I unplugged it. Disproving my belief that all modern computers are insanely powerful, I had to figure out how to make the game run at the same speed no matter how fast the computer was.

To do so, I changed the "speed" of the car to pixels/millisecond. Then, when updating the vehicles' distance, I did so by multiplying it by the time since the last update. This was simple enough, and it only required saving the time at each update for future reference.

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