Pneumatics Workshop

1 Pneumatics

•Warren Venema – Senior Mechanical Engineering Major at TCNJ – Active in FIRST since 2011 • Alumni of FRC 1403

2 Basic Linear Motion

Non Electric Pneumatics – Air Pressure Hydraulics – Oil Pressure

•Air is Compressible •Oil is Incompressible

3 Primary Function

Exhaust air is vented Pressurized air enters port, exerting a force on the piston (psi – pounds per square inch)

Work is done by the shaft connected to the piston

4 Pneumatics

How much force can the cylinder exert?

2 Force = air pressure (psi) * piston area (in ) 2 2 Force = (lb/in ) * in = (lb)

Force

5 Pneumatics

How much force can the cylinder exert?

1” Diameter-1/4” Shaft 1” Diameter 2 2 .736 in .785 in

Force

6 Components

Components of a Pneumatic System: ● Compressor ● Storage Tanks ● Pressure Switch ● Solenoid Valve ● Regulator ● Fittings ● PCN (Pneumatics Control Module) ● Relief Valve ● Gauge ● Tubing ● Dump Valve ● Actuator or cylinder 7 Compressors

Factors to Consider • Motorized pump that compresses air • Weight • 1 can be purchased via FIRST choice (30 credits) • Size • Teams received a new model in 2011 • Must use a Pneumatic Control Module to power • Cost • Amount of air required compressor • Onboard storage ViAir 90C (KOP) Thomas 215 Thomas 405 (Older)

Pros – Light, small, Pros – Light, Small and reliable, and continuous Cheap ($64) Pros – Continuous use, air use Cons – Underpowered and flow, and durable Cons – Heavier than ViAir runs HOT, cool down time Cons – Heavy, large and (.5lbs) and cost 2x the (30 minutes) expensive ($250+) 8 price Storage Tanks

• Tank that holds reserved compressed air Factors to Consider • 1 can be purchased via FIRST choice (10 credits) • Weight • Mounted before pressure regulator • Size • Must have at least a working pressure of 125 psi • Cost • Must have at least a burst pressure of 250 psi • Amount of air required

Andy Mark Plastic Tank (2011) Clippard Metal Clippard Plastic (2015)

Pros – Light, cheap ($10), Pros – Durable, shapes, and air volume (more than and sizes comparable metal tank) Cons – Heavier and Pros – Light, Cheap, Cons – Limited size and expensive ($28) Max Volume shapes, Plastic or no Cons – Limited Sizes, thread connections Push on Conn. Fragile 9 Components

● Pressure Switch Turns off compressor @ 120 psi Turns on at lower pressure ● Regulators Adjusts air pressure to working air pressure of 60 psi or less

● Relief Valve (mount on compressor) Safety device that releases air if pressure in the system reaches 125 psi

● Gauge Meter that shows the air pressure in the system at that point

● Dump Valve Manual valve used to exhaust air in the system Must be easily accessible

10 Components Cont.

Components of a Pneumatic System: ● Actuator or Cylinder Device that creates mechanical motion ● Tubing Plastic hose that carries pressurized air Must have ID of .160”

● Fittings Brass or plastic connectors Use Teflon tape on threads for air tight seal McMaster-Carr Quick Assembly Brass Compression Tubing

11 Solenoid Valves

• Valve that is controlled by the robot code Factors to Consider • Diverts air to desired air cylinder • Weight • Max Cv of 0.32 and only one valve per actuator • Size (2013) • Cost • Controlled by PCM • Amount of air required • Available in single or double valve, and 12 or 24 Volts • (1) FestoFesto Double Solenoid Valve (FIRST included Choice) in KOP (24Volts)

Double Valve Single Valve

12 Controllers

Control

● Pneumatics Control Module Directly controls and supplies power to compressor Directly powers and controls the Pressure Switch Directly powers and controls up to 8 single or 4 double Solenoid Valves

13 Pneumatics Layout

14 2017 Pneumatics

15 Wiring

After properly setting up your Robo-RIO and all the related electrical equipment the following instructions will result in a working pneumatics system Compressor 1.Wire the compressor to the Pneumatic Control Module (Power)

Pressure Switch 1.Connect switch to Pneumatic Control Module (PCM)

Valves After assembly of the kit valves with the included wire we can now wire the solenoid valve to the Pneumatic Control Module Solenoid s (Double Acting Valves only) 1.Wire both 1 and 2 from both sides of the valve to the ports on the PCM

16 Pneumatic Control

Module

17 Control Board

18 Mounting

Cylinder allowed to pivot, Avoid side forces

19 Resources / Links

• AndyMark inc. – www.AndyMark.com • Vex Pro – http://www.vexrobotics.com/vexpro • Chief Delphi – www.cheifdelphi.com • First Robotics – www.usfirst.org • Cougar Robotics Team 1403 – http://www.cougarrobotics.com • Robotics Eagles Team 358 (Great Tutorials, Documents, and Step by Steps) – www.team358.org • Simbotics Team 1114 (Workshops) – www.simbotics.org 20