Thursday, 2 October 2008

Date: 25-9-2008

Duration of activity: 2.5 hours

Group members participating: Thomas, Rasmus, Peter

The Goal of the session...: Building a Linefollower.

Setup:
We built the 9797 car once again, and loaded Linefollower onto the nxj. (Linefollower uses BlackWhiteSensor).

Experiments:

BlackWhiteSensor:


Because we already tested the lightsensor (week 1) we decided to skip straight to consturcting the ColorSensorClass.


ColorSensor:


Our first attempt at a colorsensor just sampled values for black, white and blue, and when asked which color it was on, it calculated the difference between a reading and these values, returning the color that had the least difference. The problem with this approach, was that whenever a blue was reported, the car stopped, because it thought it had reached the goalzone.

We modified the colorsensor, so you had to ask for a boolean on each color and we modified the car, so it counted the number of times a blue was reported. The car did not stop until 10 blues had been reported in a row. (A false reset the count).

Here are the final versions of



ColorSensor
and
LineFollower

No comments: