It is desired to synthesize a linkage to guide the movable shelf through the tree positions shown in Fig 1. The first position is level with the top of the cabinet for writing purposes, and the third position is a stored position for the shelf Grounds pivots should fall within the cabinet while the linkage size should be minimized so as to take up the least amount of cabinet space. Find the acceptable locations of ground and moving pivots by graphical method and add a driver dyad to limit the motion to the range of positions designed.

 

Shelf Cabinet