Robert W. McLaren

An application of fuzzy algorithms in a computer access security system

Abstract This paper describes a new approach to securing access to a computer system based on measurements of the time duration between keystrokes when a password is entered. Using fuzzy Pattern Recognition Algorithms, two recognition systems were devised and tested. The purpose of this paper is to investigate several methods of assigning class memberships to sets of vectors, and to examine the effects of initialization schemes in the fuzzy classifiers in these pattern classifiers.

Real-time robot path planning using the potential function method

Abstract An important problem in robotics is path planning, whose goal is to find a collision free path among obstacles in the work space. Most algorithms which have been developed to solve this problem are based on a mapping of the given problem into a finite state space which always resulted in a problem which can be solved by computer but has a high computational complexity. Previously developed algorithms which worked with continuous space were relatively unsophisticated. In a previous paper by the authors, an algorithm for collision avoidance was developed. This algorithm will now be incorporated into the potential function method for planning a collision free path.

Obstacle avoidance in path planning using intersection constraint search

Abstract An important problem in robotics is to determine an obstacle avoidance control strategy which transfers the system along a collision free path among obstacles in the work space. Most algorithms which have been developed to solve this problem are based on a mapping of the given problem into a finite state which always resulted in a problem which can be solved by a computer, but has high computational complexity. Certain previously developed algorithms worked with continuous problem space, these algorithms were referred to as continuum algorithms and were relatively unsophisticated when compared to the continuous algorithms. This observation has served as a motivation for the research reported in this paper, in which it is desired to provide continuous space algorithms with a more rigorous theoretical base. The main result of this work is the development of a real-valued function, Ω, which characterizes the proximal relationship of two non-point convex bodies. This function is different from similar functions reported on elsewhere in that it also provides useful information when the sets (bodies) under consideration intersect. In this paper, the need for such a function is established, and certain computationally useful properties of the developed function are demonstrated.

A microcomputer-based controller for a single-phase, 2 HP DC motor drive

This paper describes a microcomputer-based controller for a single-phase, 2-HP DC motor drive. Hardware, software, and systems aspects are discussed. Alternative control algorithms are presented. Results of system operation are given.