Abstract: A movement sensor for a multi-bar positioner includes a first section having a curved corner reflector (76), a second section (70), and a third section with an analog position-sensitive-photodiode (84). The second section (70) has three LEDs (72, 82) and four photodetectors (74). Two of the LEDs (72) and the four photodetectors (74) face a first direction towards the corner reflector (76). The third LED (82) faces a second direction, different than the first direction, towards the position-sensitive-photodiode (84). The second section can be mounted on an arm of the positioner and used in conjunction with the first and third sections to determine movement or position of that arm.

Abstract: An apparatus for positioning an end-effector comprising a multi-bar linkage drive mechanism. The drive mechanism has a base structure of a movable arm structure. The moveable arm structure has four arms arranged in a general parallelogram profile with a center of gravity at a main shaft located at a connection of two of the arms. Two of the arms have energizeable electromagnetic coils and the base structure has permanent magnets for moving the arms. Analog and/or digital position sensors can be used. Dynamic balancing can be provided to produce reactionless ultra-high speed X-Y motion. A torque cancellation motor for cancellation of Z-axis moments produced by these coils can be provided. A Z-direction actuator can also be provided.