[01] Timothy Sands, Department of Mechanical Engineering, Stanford University, Stanford, USA.

This research paper describes a development to eliminate phase lag permitting a single commercially available sensor (Global Positioning System, GPS receiver) to provide full-state knowledge (including angular acceleration), eliminating the need for accelerometers, rate gyros, and other sensors. GPS position data is used to provide full-state estimates using high gain observers, and two topologies (Gopinath and Luenberger) are examined and compared, and example preferred design choices are discussed. Observer gain tuning is illustrated and assertions are evaluated via simulations. A major weakness of feedback state observers if phase lag (90 degrees per unit of system order) so in particular, novel methods are introduced to achieve near-zero phase lag state estimation at all frequencies.

Topologies, Estimation, Gopinath, Luenberger, Phase Lag, Full State Feedback, GPS

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