1. Design modification made to the radiation shield (option 2) since the OSAKA meeting Stephanie Yang

2. Fig. 1 Fig 2 Fig 3 Fig 4 The design allows a total manual operation with the aid of a simple jig

3. Extruded nib to limit rotation of link

5. 3-D view of the shutter positioning lever

6. Main points about the option design:- Low cost construction; Completely manual operation using temporary shutter positioning lever; Temporary jig can be stored away during normal operation of the experiment; Using bellow to maintain vacuum seal while allowing shutter movement is a proven technology; Chosen bellow configuration can be bought as a standard item; Two bellows of 250mm each to be spliced to form one complete bellow to satisfy the required travel distance; Linear movement of shutter uses standard linear motion with ball bearing; Option 2 is a truly simple design and we would recommend the technical board to accept this design