Design and characterisation of 3D-printed magnetic field sensors

Abstract

Lorentz force base 3D printed magnetic field sensors are investigateed in this thesis. The sensing priciple is based on the detection of modulated light flux from two stencil masks by relative in-plane movement. Hence, one mask is part of the movable mass which is actuated by Lorentz forces, whereas the second grating is aligned on the opposite side and fixed tonto a stationary frame. Two unique designs are proposed, both are exhibiting the in-plane delectable mass for light modulation but they differ in the sensing approach. The first prototype exhibits the effective sensing area on the mass and is designed with a distinct eigenfrequency yielding in-plane deflections, whereas the second prototype features a complient mechanism. This mechanism consists of curved springs that traqnsform out-of-plane oscullations from sensing cantilevers into an in-plane movement of the mass. Advantages of 3D printing technologies in terms of fast design and accelerated testing phases as well as the possibility of creating printed "real" three dimensional MEMS structures are discussed. Therefore, this work focuses on rapid prototyping which is an effective assessment tool to demonstrate working principles for designs before initiating costly tradtional MEMS technology.