Well, it could be a four way flow control valve if you don't need an "off" position. Or if you can find a servo with 300 degree action it can have six positions. The photo is shown with only one tube, but you will need a tube for each input you want to control. The inner disk rotates, pinching all but one input at a time.
This thing was inspired in part by this guy's video http://www.youtube.com/watch?v=0h9cLpLw_9E&feature=player_embedded.
UPDATE: Video of this thing in action: http://www.youtube.com/watch?v=eBHl2WdncW0
| FlowControl.java | 2.2KB | |
| pinchwheel.scad | 5.0KB | |
| pinchwheel.stl | 775.1KB | |
| pinchwheelaxel.stl | 4.0KB | |
| pinchwheelbase.stl | 22.6KB | |
| pinchwheelbraces1.stl | 10.9KB | |
| pinchwheelbraces2.stl | 10.9KB | |
| pinchwheelcenter.stl | 44.2KB | |
| pinchwheelcross.stl | 50.3KB | |
| pinchwheelholder.stl | 61.5KB | |
| pinchwheelmount.stl | 71.7KB | |
| pinchwheelouter.stl | 418.6KB | |
| pinchwheelpcbholder.stl | 36.4KB | |
| pinchwheelslider.stl | 12.8KB |
