A tripod mechanism for parallelism alignment: Kinematics analysis and application

This paper presents a novel tripod mechanism used for precise parallelism alignment of one substrate plate with respect to another. The orientation of the top substrate plate is aligned through adjusting the lengths of pods. The parallelism of the two plates is measured through an on-board force sensor. To facilitate alignment, kinematics analysis of the tripod mechanism is conducted, and position and velocity of the carrier plate are formulated in a closed form. The tripod mechanism has been successfully applied in evaluation of a quantum tunneling linear encoder.