**CONNECTING THE PROPORTIONAL VALVE TO THE AIR COMPRESSOR **

 You will need one of this air compressor tool , that you can open and close the air flow between the air compressor and the proportional valve. Connect this tool to the proportional valve , on the input port of the middle (opposite side of the output ports ) as shown in the pictures bellow
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**TESTING THE PROPORTIONAL VALVE**

 Be sure that your code works testing the relation between the proportional valve and your encoders. If you did everything right at the Coding section , when you upload the code into the Arduino and let it run , the system will be steady , and it will move if you move the encoders. To be sure that its working , take the rotational encoder and rotate it and see if the movement of the cart is in the right direction in order to balance the pendulum. In my case , when i rotate the encoder clockwise , the cart should drive backward , to balance it. 

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