Integrating generic sensor fusion algorithms with sound state representations through encapsulation of manifolds

  • Authors:
  • Christoph Hertzberg;René Wagner;Udo Frese;Lutz SchröDer

  • Affiliations:
  • SFB TR/8 Spatial Cognition, Universität Bremen, Postfach 330 440, 28334 Bremen, Germany and Fachbereich 3 - Mathematik und Informatik, Universität Bremen, Postfach 330 440, 28334 Bremen, ...;Deutsches Forschungszentrum für Künstliche Intelligenz (DFKI), Sichere Kognitive Systeme, Enrique-Schmidt-Str. 5, 28359 Bremen, Germany and Fachbereich 3 - Mathematik und Informatik, Uni ...;SFB TR/8 Spatial Cognition, Universität Bremen, Postfach 330 440, 28334 Bremen, Germany and Fachbereich 3 - Mathematik und Informatik, Universität Bremen, Postfach 330 440, 28334 Bremen, ...;Deutsches Forschungszentrum für Künstliche Intelligenz (DFKI), Sichere Kognitive Systeme, Enrique-Schmidt-Str. 5, 28359 Bremen, Germany and Fachbereich 3 - Mathematik und Informatik, Uni ...

  • Venue:
  • Information Fusion
  • Year:
  • 2013

Quantified Score

Hi-index 0.00

Visualization

Abstract

Common estimation algorithms, such as least squares estimation or the Kalman filter, operate on a state in a state space S that is represented as a real-valued vector. However, for many quantities, most notably orientations in 3D, S is not a vector space, but a so-called manifold, i.e. it behaves like a vector space locally but has a more complex global topological structure. For integrating these quantities, several ad hoc approaches have been proposed. Here, we present a principled solution to this problem where the structure of the manifold S is encapsulated by two operators, state displacement :SxR^n-S and its inverse :SxS-R^n. These operators provide a local vector-space view @d@?x@d around a given state x. Generic estimation algorithms can then work on the manifold S mainly by replacing +/- with / where appropriate. We analyze these operators axiomatically, and demonstrate their use in least-squares estimation and the Unscented Kalman Filter. Moreover, we exploit the idea of encapsulation from a software engineering perspective in the Manifold Toolkit, where the / operators mediate between a ''flat-vector'' view for the generic algorithm and a ''named-members'' view for the problem specific functions.