Active Positioning and Passive Fixation using Friction: in Capacitive Displacement Measurement Applications

Sensor positioning is critical for achieving a measurement accuracy in the picometre range with capacitive displacement sensors. This thesis discusses the contradictory requirements that the sensor alignment application imposes: motion capability combined with extreme displacement stability. In addition, it explores three micrometre scale positioning methods that do not compromise the position stability. All three positioning methods use the properties of friction contacts to achieve the combination of stability and position ability.