Warlocks 8/5/05 TMU FIRST Robotics 101 u Week 1) Gears, Pulleys, Sprockets, Bearings u Week 2) Motors & Controls u Week 3) Pneumatics u Week 4) Materials & Fasteners u Week 5) Drivetrain and Framing Options u Week 6) Arm & Winch Options u Week 7) Team Building

Warlocks 8/5/05 TMU Have You Got Gas? Do You Have a lot of Hot Air? u Then you will probably like Pneumatics! u Pneumatics- Compressed Gas u The most famous Pneumatic invention of the 20 th century was the Pneumatic Tire. Imagine a tire without air (solid tire). What a rough ride! In the 1920s and 1930s came a new smooth riding tire …Its Pneumatic (full of pressurize air) and made for a smoother ride…..

Warlocks 8/5/05 TMU And in the 21 st Century they put Pneumatic Tires on Robots u Robots now have a smoother ride with Pneumatic tires, but that is not exactly what FIRST meant when they said Pneumatics. This is what they meant: Compressed Air Tank Geek Safety Glasses FORCE 60 lbs to 100 lbs Pneumatic Cylinder Whoa ! Plunger Diaphram

Warlocks 8/5/05 TMU Force=Pressure X Square Area u Calculations Compressed Air Tank FORCE= Area of Diaphram (inches) X Pressure (PSI) in tank. Pneumatic Cylinder Plunger Diaphram 1.5 Sq Inches 60 PSI = 1.5 X 60= 90lbs of Force Stroke Length

Warlocks 8/5/05 TMU Pros and Cons of Pneumatics u Reasons for using Pneumatics –Weight: May be less weight than using Gears and Pulleys while keeping the same Force with perhaps the exception of the compressor. –Simple to Design/Easy to Build: A closed loop pneumatic system is easier to design than gears and pulleys. –Force is adjustable and the Force pneumatic produces can be significant. –Offers movement or actuation in a straight line rather than rotational movement. –A variety of pneumatic cylinders are offered. u Issues with Pneumatics –Compressor weight (7 to 10 lbs): need to keep air usage to a minimum to not use compressor. –Stroke Length is limited to 6 inches to 2 ft max. (There are limits). –Need to fill tanks after every match besides changing battery. –Leaks are possible and can be annoying to find.

Warlocks 8/5/05 TMU Pneumatic Parts u Compressor, 125 PSI, 20 Amps Max, Weight 7.5 lbs u Pressure Switch, 115 PSI u Air Tanks (2 per robot) small (Remember Not Much Air) Can be put on Robot but I have not seen any of robots have the weight in six years!

Warlocks 8/5/05 TMU Pneumatic Parts u Regulator to regulate pressure to components: u Single and Double Solenoid Valves: u Flow Control Valves Change speed of extending and retracting: Single=> On=Extend, Off=Retract Double=> Side 1 On Pulse Extend Side 1 Off Same Position Side 2 On Pulse Retract Side 2 Off Same Position Usually it is 60 PSI or Less; 2 Regulators are provided for regulating High Pressure System and Low pressure system simultaneously. Too Fast, Slow it down with Flow control.

Warlocks 8/5/05 TMU Pneumatic Parts u Valve to Release or Fill with Air u Fittings u Cylinder (Various Sizes) Diameter Range: ¾”; 1 ½” ; 2” Stroke Range: ½” to 24” Force Range at

Warlocks 8/5/05 TMU Forces of Cylinders u Force Range

Warlocks 8/5/05 TMU Rotary Actuator u Rotary Actuator Rotational Force =Torque (0.075/2) 2 * PI X 60 PSI = 0.26 ft-lbs (0.875/2) 2 * PI X 60 PSI = 36 ft-lbs (1.06/2)2 * PI X 60 PSI= 52 ft-lbs

Warlocks 8/5/05 TMU Pneumatics