J Jaron Achterberg

Coil Array Structures Compared for Contactless Battery Charging Platform

We propose two new coil topologies for a contactless battery charging platform. The new topologies consist of square printed circuit board (PCB) coils, grouped in two layers on a PCB. We compare the new topologies to each other and to a previously published topology that consists of three layers of hexagonal coils. For each topology, the magnetic flux density is calculated above the coil layers. In addition, the position dependence of the flux linkage between the primary coil array and a secondary coil is simulated and compared for all three topologies. For one of the new topologies, we compare the simulations with measurements.

Modal observer design for a flexible motion system with state dependent sensor positions

This paper focuses on observer design for a flexible motion system with a state dependent output map. After rewriting the modal system to parameter varying form sufficient conditions are derived to obtain a parameter varying modal observer with bounded ℒ2 gain. These conditions translate to linear matrix inequalities (LMIs) when the time derivative of the Lyapunov function is multiconvex. The derived theory is applied to a model of the Herringbone Pattern Planar Actuator (HPPA) where noise and input disturbance affect the system. Using the theory it is possible to estimate independent rigid body motion in six degrees of freedom (DoF) and two flexible modes.

Implementation of a linear quadratic bumpless transfer method to a magnetically levitated planar actuator with moving magnets

A linear quadratic bumpless transfer technique for a six-degree-of-freedom planar actuator with integrated active magnetic bearing is proposed to solve the lift-off and landing problem by switching between different controller sets. The need for multiple controller operation states results from the difference between robustness and wind-up concerns during lift-off and landing and the high performance tracking requirements for accurate operation. A procedure for tuning the plant input and error matrices used in the Linear Quadratic Bumpless Transfer method based on new observations is presented. The procedure has been applied to synthesize a bidirectional bumpless switching mechanism that was successfully applied and tested on a 6 DOF laboratory setup.