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A Bio-Inspired 3-D Neural Compass Based on Head Direction Cells

Head direction cells (HDCs) in mammals’ brains are thought to provide the sense of direction (function of a compass). They fire when the animal’s head points to a specific orientation. In this paper, a bio-inspired neural compass with 3 degrees of freedom (DOFs) which is consistent with neurophysiological characteristics of biological HDCs in three-dimensional (3-D) environments is proposed. The proposed model, which is based on continuous attractor neural network (CANN), is primarily driven by angular velocity of head turning to determine spatial orientations of unmanned vehicles in 3-D environments. By means of Hebbian learning, external perception information such as visual landmarks can be incorporated to calibrate cumulative errors of path integration based on self-motion information. Experimental results obtained by validating the model on a two-axis motion simulator are given. The neural system enables the simulator to track its spatial orientations in 3-D environments effectively.