We focus on the micro-stage of a new high resolution positioning machine. One of its key features is the use of flexible circular notch hinges for passive joints. After a reminder of the micro-stage architecture and its inverse position and velocity kinematics solutions, a force model is developed for the choice of the actuators. This model takes into account the flexible R (Revolute) joints modeled as torsional springs and the external forces applied on the traveling plate. Simulations are conducted to evaluate both kinds of forces and result in the choice of the appropriate actuator. The final design of the micro-stage is presented as well as the obtained prototype.