Pneumatic servo valve for air muscle

thingiverse

Hello Everyone, This pneumatic servo valve was designed to fully control an air muscle. It can be used for a pneumatic powered robot, exoskeleton, or any compressed air application. It allows proportional control of two ports (in and out) using only one hobby servo motor. This means you can get any configuration of the two ports independently: Closed/Closed, Open/Closed, Closed/Open... but also any position in between, so it can be partially opened across all ranges to control power! With this system, you can fully control an air muscle or air cylinder with only one servo, requiring just one output from your microcontroller. This design works by using a camshaft pressing on two pistons. The camshaft is directly mounted on the servo shaft and the pistons are in contact with the cam through small bearings. You will need to insert a silicon tube (8 mm outside diameter) all the way into the casing. The pistons will press on the silicon tubes, closing or opening air flow. Then connect the silicon tube to some PTFE tube by sliding it inside the silicon tube at least 1cm inside the casing. This design allows for proportional control of air flow, locking a muscle in a specific position or using a specific amount of force. I couldn't find something similar available commercially at a reasonable price. Almost all commercially available valves like the cheap AirTac ones are only ON/OFF devices with no easy way to control flow. This compact valve can be easily integrated into any project you may have. I tested mine for several hours and it worked very well. Feel free to use it and share whatever you created using it! I hope this will be useful to someone!