Alastair Harrison

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In this paper we describe a body of work aimed at extending the reach of mobile navigation and mapping. We describe how running topological and metric mapping and pose estimation processes concurrently , using vision and laser ranging, has produced a full six-degree-of-freedom outdoor navigation system. It is capable of producing intricate three-dimensional(More)
—This paper describes a novel method for determining the extrinsic calibration parameters between 2D and 3D LIDAR sensors with respect to a vehicle base frame. To recover the calibration parameters we attempt to optimize the quality of a 3D point cloud produced by the vehicle as it traverses an unknown, unmodified environment. The point cloud quality metric(More)
— This paper is about estimating a smooth, continuous-time trajectory of a vehicle relative to a prior 3D laser map. We pose the estimation problem as that of finding a sequence of Catmull-Rom splines which optimise the Kernelised Rényi Distance (KRD) between the prior map and live measurements from a 3D laser sensor. Our approach treats the laser(More)
This paper describes the design, build, automatic self-calibration and evaluation of a 3D Laser sensor using conventional parts. Our goal is to design a system, which is an order of magnitude cheaper than commercial systems , with commensurate performance. In this paper we adopt point cloud " crispness " as the measure of system performance that we wish to(More)
This paper describes a body of work being undertaken by our research group aimed at extending the utility and reach of mobile navigation and mapping. Rather than dwell on SLAM estimation (which has received ample attention over past years), we examine sibling problems which remain central to the mobile autonomy agenda. We consider the problem detecting(More)
We examine why a probabilistic approach to modelling the various components of spatial language is the most practical for spatial algorithms in which they can be employed, and examine such models for prepositions such as`between' and`by'. We provide an example of such a probabilistic treatment by exploring a novel application of spatial models to the(More)
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