Lego NXT & LeJOS Table Mapping & Navigation

So I did this mini project over the summer but it has been collecting e-dust ever since, and I thought a nice way to finish it off would be to write a small blog post.

The idea is that I wanted to make my NXT map and navigate a quadrilateral table after being placed at any point and angle on the table. I won't delve to deeply into details as the PDF covers the technical side and the code speaks for itself, but long story short it works quite nicely, and theoretically perfectly... But as is the way with the NXT and its various bendy Lego Meccano pieces, things are calibrated for an infinitesimally small time frame. In fact I probably spent at least just as long calibrating the NXT as I did programming and writing the PDF! The idea is that by following the PDF and using the different programs in the Git repo, it can be repeated on any NXT using only the light sensor.

The GitHub repository; https://github.com/philleonard/LeJOS-NXT-Mindstorm-Navigation.git
The PDF can be downloaded here if you find the PDF viewer below a little small.

Cheers!
Phil

NXT Fibonacci

I have just received my Lego NXT Mindstorm! I immediatley flashed LeJOS on the brick, and before I got to work on some AI, I decided to create a little program which represented the Fibonacci sequence terms as bursts of the motors.

import lejos.nxt.*;

public class fib {
 
 public static void main (String[] args) {
  
  //Limit the sequence.
  int fib[] = new int[100];
  
  //First two terms in sequence are 1
  fib[0] = fib[1] = 1;
  
  for (int i = 2; i < fib.length; i++) {
   //Calculate, and print next value in Fibonacci sequence
   fib[i] = fib[i - 1] + fib[i - 2];
   LCD.clear();
   LCD.drawInt(fib[i], 6, 4);
   
   //Move forward for the length of the Fibonacci number
   Motor.C.forward();
   Motor.A.forward();
   try{
    Thread.sleep(fib[i]); 
   } catch (Exception e) {}
   
   //Sleep for a tenth of a second.
   Motor.C.stop();
   Motor.A.stop();
   try{
    Thread.sleep(100);
   } catch (Exception e) {}
  }
 }
}