Lego nxt soccer robot
If your robot has the light sensor plugged in to a different socket, you will have to change this code. If a robot Soccer player that has gone over the edge of the green and black playing field into the white surround, the code above will cause the Robot to retreat backwards on to the Soccer field. It works like this: The command above will tell motors A and C start to go backwards, taking the Robot back towards the playing field.
I have used power However a greater power could be used when testing is complete. The circled loop above will allow motors A and C to continue running backwards sending the Robot backwards until the Robot is back in the Soccer field.
The code above is quite sufficient to tell our Soccer Robot to go back to the mat. They will continue running after leaving the loop. This may confuse us when this code is inserted in to our Soccer program. It is important to test that this code works, before using it as part of a bigger Soccer program. To do this we download this program into our Soccer Robot, and run it. When placed on your Robot Soccer mat, the robot should do nothing if placed inside the playing field, but should retreat backwards if placed anywhere on the white border surrounding the Soccer playing field.
This video demonstrates this. If your robot goes backwards into the Soccer field when placed on white, and does nothing when placed in other parts of the Soccer field , your code snippet has been tested and proven reliable.
It can now be used as part of a Soccer playing program. When everything is good, go on to the next step where we can find out how our Soccer Robot finds the ball! Soccer Tactics 1 - Stay on the Soccer Field! Which readings will we use to tell our robot that it has left the Soccer field?
Note that we have connected the two blocks by a yellow wire. This allows the direction number to go from the Seeker block through the yellow wire to the Mathematics block.
If you forget to do this, the program will refuse to work! To do this we need a loop. In the code above, the mathematics block is connected to the loop with a green wire. This code will allow your robot to leave the loop and obey the next command following the loop. We haven't put that next command in yet, but will soon. There are lots of things we can tell our robot to do after it finds the ball.
However, just so we can test that our code works, let us tell our robot to go forward one rotation each time the ball is seen. The code above causes motors A and C to turn one rotation, causing the robot to go a short way forwards. The loop in the code above causes the whole code to keep repeating forever, or until we turn our robot off. This complete program causes the Robot to keep finding the Soccer ball, and following it - which is what we wanted.
Download this program to your robot, and test it to see that your robot does what you want it to do. If there are problems, carefully check the diagrams above to make sure you have understood the method we have outlined above.