Problem with travel()

[ck]

Hi everyone,

Correct me if I am wrong on this one but the travel() method in class SimpleNavigator
doesn't make the motors go backwards when dist is negative.

This happens because at left.rotate(-counts); right.rotate(-counts);
"counts" is already negative, so it becomes positive again!!!

Code: Select all

 public void travel(int dist) {
        int counts = (int)(dist * COUNTS_PER_CM);
        
        left.resetTachoCount();
        right.resetTachoCount();
       
         if(dist > 0) {
            left.rotate(counts);
            right.rotate(counts);
         } else
         if(dist < 0) {
            left.rotate(-counts);
            right.rotate(-counts);
         }
         while (left.isRotating() || right.isRotating());
         moving = true;
         stop();
      }


I tried out the following version of travel() and works fine
(given that COUNTS_PER_CM is always positive) :

Code: Select all

 public void travel(int dist) {
      int counts = (int)(dist * COUNTS_PER_CM);
        
      left.resetTachoCount();
      right.resetTachoCount();
                   
      left.rotate(counts);
      right.rotate(counts);
              
      while (left.isRotating() || right.isRotating());
      moving=true;
      stop();
    }


Am I right? ...or have I just caused more problems?

[bbagnall]

I think you're working with the now very outdated leJOS NXJ code. Much of this has been changed or fixed by now in our main code. If you browse subversion on our Sourceforge project there's a snapshot project that has updated stuff.

[ck]

Could you send me the link for that...
I searched the SourceForge web site and I can't find anything exept from lejos_NXJ_win32_0_1_0alpha.zip (2007-01-10)

Thanks
Constantinos

[migerh]

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