Help with pneumatics

[DonRotolo]

The compressor increases the pressure of air, so it can perform work. You need to pipe this air to a Pneumatic Cylinder, so that it can move the Piston inside the cylinder, creating a mechanical motion of some sort.

Between those two things is a bunch of hardware.

First off, right out of the compressor is called the "high pressure side", because the air pressure is higher than allowed for Cylinders. You use the Primary (all black) Regulator to lower the pressure to a maximum of 60 PSI. (The regulator must be connected a very specific way for in and out - look it up.) You can see the pressure because you MUST install one Pressure Gauge in the "low side" after the regulator. The Low Side pressure is then distributed to one or more Solenoid Valves, which are switches to change where the air goes to make the Piston inside the Cylinder move.

On the High Side, you MUST install several components - read the rules. These include a pressure Gauge to see the high side pressure, a Pressure Switch to signal the cRio when to turn the compressor on and off, a Pressure Release Valve to vent all air pressure from the system, and a Pressure Relief (safety) valve, which you MUST calibrate to pop off (release pressure) at 120 PSI before using it.

Also on the high side, it is recommended to install one or more Accumulator Tanks. Your compressor can't move a lot of air quickly, so accumulators help by storing high-pressure air for later use. Not a lot, but 2 or 3 tanks is typical. The more air you use, the more tanks you will want. Note that there are accumulators made of plastic that are FRC legal, as well as the metal one you got in the kit.

There is a TON more info you need to build an effective pneumatic system, but this is the basic idea. FIRST has lots of info on their site that will help.

[tilky]

i need help with the programming part of it

[vhcook]

What you do in software is going to depend on what you do electrically. You have several choices to make. You can either wire your solenoids to the solenoid breakout on a solenoid module in your cRIO, or you can use Spike Relays. A cRIO solenoid module can power either 12V or 24V solenoids, but not both at once. You need to pick one or the other and make every solenoid you connect to it is expecting that voltage .

I'm going to talk you through the simplest method to code, which uses the solenoid module.

Assume you have a piston that extends (forward) and retracts (reverse). You will need to connect a solenoid to each direction to control the airflow. For our purposes, you'll generally want the solenoid on the forward end to be set to the opposite of the reverse end. That is, if you're applying pressure on the forward end, you'll want the reverse end to be open to exhaust and vice versa. You may mechanically use a double solenoid or two single solenoids, but either option will use two solenoid ports on your solenoid breakout and they can both be coded the same way.

In Labview, start by defining the solenoid ports in Begin.VI. You'll use a Solenoid Open, and a Solenoid Set Reference. The easiest method is to call it a double solenoid (even if it really is two singles), and assign the correct Solenoid Port to each end. Give it a better name than in my example (attached) - you want something that describes what it does and that you can spell consistently.

Then when you want to use it, use the Solenoid Set VI (other example). Note that it's been two years since we used pneumatics, so I may have the following settings exactly backwards - test with care . Forward sets the Extend end to pressure and the Retract end to exhaust, Reverse does exactly the opposite. (Off and On, while present, are generally not settings you want. Off sets both to exhaust. On sets both to pressure.)