Development of software system for constraint control of mobile sensors in wireless sensor networks.

摘要

Groups of mobile sensors can be used in a wide variety of applications ranging from search and rescue operations, reconnecting a disconnected sensor network and in surveillance applications. These applications may require the mobile sensors to move in such a way that they satisfy certain constraints. Some of the constraints may be node degree of connectivity, sensing coverage area and obstacles avoidance in the environment. Therefore, an efficient constraint control strategy is required for the mobile sensor platforms to move and properly disperse themselves in the environment at the same time satisfy the specified constraints. The constraints taken into consideration in this research are; sensing coverage, communication connectivity, and sensing and communication range overlaps. In this thesis control strategy for constrained control of mobile sensors was developed, presented and tested. The system engineering approach was followed during the development process of the software implementing the constraint control strategy. The system of interest was broken into two subsystems, i.e, movement planning subsystem and movement action generation subsystem. Alternative methods for designing and implementing the above two subsystems were discussed, compared and best alternatives were used in the development of the software system. Finally, the two subsystems were integrated and the integrated software system was tested as a whole by simulation. Simulation results showed successful implementation of the developed software. The software was tested under different environmental conditions, with obstacles and without obstacles in the environment. In all scenarios, the objective set for the mobile sensor was accomplished and the mobile sensors satisfied the required node degree, specified to it by the user, maintained communication connectivity and maximized the sensing coverage area. The developed software system for constraint control of mobile sensors is expected to assist the US Army and other agencies in conducting efficient and effective surveillance operation in battlefield and sensitive security areas. The system developments and simulation results of the constraint control software is presented in this thesis report.