Sensor Fusion and State Estimation of the Robot

Abstract

In this chapter, we review previous estimation and sensor fusion approaches in the field of humanoid robotics. The focus is primarily but not exclusively on state estimation. Humanoids are modelled as free-floating mechanical systems subject to external forces and constrained by whole-body distributed rigid contacts. Besides state estimation, a number of related problems are considered including the estimation of joint torques, contact forces, contact positions, and the center of mass. Previous approaches are discussed with reference to a number of features relevant to humanoid applications: computational complexity, observability analysis, modeling accuracy, and floating-base parameterization. This chapter concludes with a section on future directions and open problems, revisited in the light of previously discussed approaches.