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Pitching Machine and Batter
Building: Advanced
Program: Easy

Building Instructions


Start by building the Baseball Batter.  Click the picture for building instructions.

Building Instructions













Use the two longest wires to connect the two motors to ports B and C on the NXT as shown below (do not cross the wires).

Pitching Machine and Batter Programming

Use the program Pitch_and_Bat for your Pitching Machine and Batter.  This program is just like the Baseball_Bat program for the Baseball Batter project with one Move block added to spin the wheels of the pitching machine.


How to Use the Pitching Machine and Batter

  1. Arrange the pitching machine and batter on the floor as shown in the last picture above.  The balls should be aimed at the ultrasonic sensor.

  2. Run the Pitch_and_Bat program.

  3. Place one of the plastic balls that come with the NXT set on the back end of the ramp.  The ramp is slightly downhill towards the wheels, so the ball should roll slowly towards the spinning wheels and then get launched through them towards the batter.  When the batter's ultrasonic sensor sees the ball at the programmed distance (14 inches), it will swing to hit the ball.

  4. If you have problems with the ball running into the long wires, you can put a piece of paper over them as shown below.


  • Experiment with different distances and angles for the pitching machine to see how it affects the hit.  Unfortunately you are limited by the length of the wires, but see how you can make the best of it.  For a building challenge, try separating the NXT brick from the batter and placing it somewhere in between the pitching machine and the batter to make better use of the available wire lengths.

  • Even with the pitching machine and batter in the same place, not all balls will be hit in the same direction.  For example, sometimes the hit will come back and hit the pitching machine, but sometimes it will go to one side and make it past.  In fact, sometimes the results are not even close to being the same.  If the motors and the program are doing exactly the same thing every time, what do think causes different balls to be hit differently?  Well, if you like reading complicated articles with lots of big words, try reading about Chaos Theory.  If you think baseball looks random when people play it, just think, even robots can't play it consistently!

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