robots don't drive straight

[rhsteach]

Hi,
Our robotics club just updated 2 robots to Lejos 0.9.0. We are finding that the robots do not drive in a straight line: sometimes they veer left; sometimes, right. It seems as if the motors are not synched, but I cannot find how to correct this. Is there something wrong with the way we set up the DifferentialPilot?
Thanks

Code: Select all

public class SetupTest
{
   static float wheelBase=15.00F; // sets width of robot from wheel to wheel
   static float wheelDiameter= 8.27F; //Sets wheel diameter
static DifferentialPilot pilot = new DifferentialPilot(wheelDiameter, wheelBase, Motor.A, Motor.B, true);
   

public static void main(String[] args)
   {     

     pilot.setTravelSpeed(25);
     pilot.setRotateSpeed(150);      
     Pilot.travel(100);

[gloomyandy]

Hi, so what software did you use to control your robot before you updated to leJOS 0.9? Did your robot run straight then? You may want to try running your robot at a slower speed. Try running it on diferent surfaces. Try setting a slower acceleration rate.

Andy

[rhsteach]

We were using 0.85 (I think), and the robots started more quickly and ran straight. Lowering the acceleration did correct the problem.

Feature Request: as time permits, could default values for such things as Acceleration, RotateSpeed, TravelSpeed, etc., be added to the documentation?

Thanks

[gloomyandy]

Hi,
just to clarify. Are you saying that the previous version accelerated more quickly than the current version, and that reducing the acceleration of the current version, that is making it start even slower fixed the problem? If this is the case that does sound a little odd...

Andy

[rhsteach]

Sorry - that was confusing. I meant, regarding:

Movement - under the old version, the robot started to move immediately after the "execute program" button was pushed. With the new version, there is a noticeable delay before the robot begins to move.
Acceleration - under the old version, acceleration was left at default values (I didn't even realize it could be adjusted). Today, with 0.9.0, I set acceleration to 100 and then to 300; in both cases the robot traveled in a fairly straight line.