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This paper explores several novel approaches to solve the Morris water maze task. In this spatial memory task, the robot must learn how to associate perceptual information with a particular location to aid in navigating to the goal. A Self-Organizing Feature Map (SOFM) is used to discretize the perceptual space. The robot must then learn to associate these perceptual states with an action used to navigate through the environment. Two navigational approaches are proposed. The first approach involves computing a probabilistic graph between SOFM nodes and then searching the graph to locate a path to the goal. The second approach uses temporal difference learning to learn the association between an SOFM node and an action that will direct it to the goal. The paper compares the effectiveness of these two approaches and discusses their respective utility.

We consider in this paper the improvement of side-attack mine detection by performing confidence level fusion with data collected from vehicle-mounted forward-looking IR and GPR (FL-GPR) sensors. The mine detection system is vehicle based, and has both IR and FL-GPR sensors mounted on the top of the vehicle. The IR images and FL-GPR data are captured as the vehicle moves forward. The detections from IR images are obtained from the Scale-Invariant Feature Transform (SIFT) and Morphological Shared-Weight Neural Networks (MSNN) depending on target characteristics, and those from FL-GPR are derived from the FL-GPR SAR images through object-tracking.Since the IR and FL-GPR alarms do not occur at the same location, the fusion process begins with each IR alarm and looks at the nearby FL-GPR alarms with confidences weighted by values that are inversely proportional to their distances to the IR alarm. The FL-GPR alarm with the highest weighted confidence is selected and combined with the IR confidence through geometric mean. An experimental dataset collected from a government test site is used for performance evaluation. At the highest Pd and comparing with IR only, fusing IR and FL-GPR yields a reduction of FAR by 26%. When the Hough transform is applied to reject the IR alarms that have irregular shapes, the fusion results provides a reduction of FAR by 35% at the highest Pd.

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