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Vector analysis is a well-developed field that deals with details about line, surface and volume integrals which can be solved analytically to provide solutions to many problems. Using vector analysis, a curve can be divided up into many small arcs, each of which is a position vector. The summation of these position vectors can be used to represent the curve in detail; this is known as the total vector field. In this paper, there is shown a vector analysis methodology when applied to the wake immediately after a moving or stationary object, caused by the movement of the object through free space or the surrounding medium moving around the object respectively. The aim was to create a system that can determine the vectors between successive images in a video with the end result being able to establish an overall trajectory of the object. This could be implemented on a Field Programmable Gate Array (FPGA) or other device to be deployed in the field to track any type of object. If the device's orientation with magnetic north-south is known, the direction of the object is travelling in can be calculated and then relayed on. This could be useful as an easily deployable warning system for the armed forces or rescue services to inform personnel of potential incoming threats. This work builds upon the Morphological Scene Change Detection (MSCD) mechanism implemented in the DSP Builder environment and describes how the changes allow the system to track the wake and plot its trajectory. System simulations of real world data are shown and the resultant imagery is then discussed. Furthermore, tests are conducted on single objects and then multiple objects to investigate how the system responds as real world situations are likely to have more than a single object.

Abstract. When performing image operations involving Structuring Element (SE) and many transforms it is required that the outside of the image be padded with zeros or ones depending on the operation. This paper details how this can be achieved with simulated hardware using DSP Builder in MATLAB with the intention of migrating the design to HDL (Hardware Description Language) and implemented on an FPGA (Field Programmable Gate Array). The design takes few resources and does not require extra memory to account for the change in size of the output image.

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The use of optical communications systems is prevalent in underwater robotics when short-range data transmission is required or preferred. This paper proposes a method of producing and testing an optical communications system for use in the assistance of optical docking for autonomous underwater vehicles (AUVs). It describes how the Simulink modelling environment was used to program and simulate a model of a transmitter, which was then implemented on a microcontroller. The transmitter model implemented on hardware was then used to produce an optical signal, which was sampled, logged and used to design a receiver model in Simulink. For signalling purposes, the experiment used a light-emitting diode (LED) with a driver circuit and photodiode based receiver. This simulated approach using real world data enabled the analysis of the system at every point during the process, allowing for a hardware in the loop style approach to be used in the receiver model design. Consequently, the Simulink Coder was used to produce the receiver model’s equivalent in C++ for later deployment. A benchmark was determined through experimentation to compare within future studies; the system was tested and found to operate effectively at distances between 1 m and 12 m in a controlled in air test environment.