1. shutter pushpull schematic2.ppt Present Manual Control System for Alcator C-Mod MSE Shutter (Schematic) We want to rotate the shutter into one of three positions: Position #1: linear feedthrough A almost fully “in” & feedthrough B almost fully “out”. Position #2: linear feedthrough B almost fully “out” & feedthrough B almost fully “in”. Position #3: linear feedthroughs A and B in an intermediate position. To ensure that all cables remain in a state of tension, the back ends of the two linear feedthroughs are connected with a restraining cable that loops around two wheels supported on fixed axles. Presently, we manually push and pull to position the shutter in the desired position. To ensure that the rotatable shutter is positioned properly, we need an accuracy of about 2 millimeters on the position of each linear feedthrough. The system of wire cables that controls the movement of the rotatable shutter is pretty “stiff”. I estimate that about 5-10 pounds of force are required to move them. If we pull too far in one direction, we will probably break the connection between the internal wire cable and the shutter. So we to provide for stops that limit the push-pull of both linear feedthroughs. Linear feedthrough A Linear feedthrough B wire cable Rotatable shutter (in vacuum) restraining cable clamps to feedthroughs rod frame supporting wheels conflats stiff tube handle

2. shutter pushpull schematic2.ppt Proposal #1 for Remote MSE Shutter Control Linear feedthrough A Linear feedthrough B 14CCF series Berg Cable chain 0.1475” pitch Need to figure out means of connection to linear feedthrough 2.5” 14LP5S-52 Berg chain sprocket Sprocket diameter = 2.4563” OD = 2.536”, 3/8” bore (pin or clamp hubs assemble on request) Optical slot switches (TBD)

3. shutter pushpull schematic2.ppt Remote MSE Shutter Control Linear feedthrough A Linear feedthrough B 14CCF series Berg Cable chain 0.1475” pitch Need to figure out means of connection to linear feedthrough 2.5” Berg chain sprocket (Size to match existing wheels) Optical slot switches (TBD) 1.0-1.75” diameter Berg chain sprocket Need belt tensioner?

4. shutter pushpull schematic2.ppt Chain sprocket shaft Torque limiters (2) Are these needed? Stepper motor Supporting Frame motor drive electronics power supply PLC optical switch outputs ? Schematic of Stepper Motor Control System