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This paper uses (linearized) Kalman filters to estimate first-order geometric parameters (i.e., orientation of contact normals and location of contact points) that occur in force-controlled compliant motions. The time variance of these parameters is also estimated. In addition, transitions between contact situations can be monitored. The contact between the manipulated object and its environment is general, i.e., multiple contacts can occur at the same time, and both the topology and the geometry of each single contact are arbitrary. The two major theoretical contributions are 1) the integration of the general contact model, developed previously by the authors, into a state-space form suitable for recursive processing; and 2) the use of the reciprocity constraint between ideal contact forces and motion freedoms as the "measurement equation" of the Kalman filter. The theory is illustrated by full 3-D experiments. The approach of this paper allows a breakthrough in the state of the art dominated by the classical, orthogonal contact models of Mason that can only cope with a limited (albeit important) subset of all possible contact situations.

With increasing demand and awareness from industries for enhanced safety, higher productivity, and better vehicle utilization, coupled with labour shortage, automating heavy equipment is becoming more and more important. Among the different types of heavy equipment, bulldozers fall into the category of machines that have a very high potential of achieving fully autonomous operation. Focusing on this fact, the aim of this research is to develop an automated path planning system for bulldozers. In general, an autonomous system is composed of terrain mapping, path planning and path-tracking. Existing commercial grade methodologies already solve terrain mapping and path-tracking, however path planning will be a key challenge for bulldozer automation.Conventional path planning algorithms are designed typically using a grid-based map, and are very versatile. However, in reality, a substantial effort is still required when applying to specific industry products. In contrast to this trend, the aim of this work is to develop a path planning algorithm specifically suitable for bulldozers, starting from the phase of theoretical development. The novel path planning methodology was developed by incorporating industry feedback, and has successfully resolved the issues which occurred when attempting to apply the pre-existing path planning methodologies. Results obtained from this newly developed methodology will demonstrate that efficient paths can be created. The methodology presented in this thesis has led to the development of automated path planning for bulldozers. This allows bulldozers to function without the need of an operator, contributing to enhanced safety, increased productivity, and solving the shortage of skilled operators.Declaration relating to disposition of project thesis/dissertation I hereby grant to the University of New South Wales or its agents the right to archive and to make available my thesis or dissertation in whole or in part in the University libraries in all forms of media, now or here after known, subject to the provisions of the Copyright Act 1968. I retain all property rights, such as patent rights. I also retain the right to use in future works (such as articles or books) all or part of this thesis or dissertation.I also authorise University Microfilms to use the 350 word abstract of my thesis in Dissertation Abstracts International (this is applicable to doctoral theses only). …………………………………………………………… Signature ……………………………………..……………… Witness Signature ……….……………………...…….… DateThe University recognises that there may be exceptional circumstances requiring restrictions on copying or conditions on use. Requests for restriction for a period of up to 2 years must be made in writing. Requests for a longer period of restriction may be considered in exceptional circumstances and require the approval of the Dean of Graduate Research.

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