The effect of stratum thickness ratio on crossflow in a stratified petroleum reservoir

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A New Approach to Robot Manipulation

This thesis discusses a new approach to the design, development and configuration assignment of Reconfigurable Robot Manipulators. It details the engineering of a new Modular, Autonomously Reconfigurable Serial manipulator platform, termed the MARS Manipulator, as well as a systematic methodology for obtaining the optimum configuration given a user-defined task. The platform consists of i) an 18-Degree-of-Freedom (DOF) serial-link manipulator capable of locking any of its joints at any position in their continuous range, such that it can emulate lesser DOF serial manipulators with different kinematic and dynamic parameters, and ii) an integrated simulation and design environment that provides a toolset for the design, implementation and optimization of a desired manipulator configuration for a given task. The effectiveness of the MARS Manipulator to adapt its configuration to various tasks is examined by assuming two well-known configurations, SCARA and articulated, and by performing a specific task with each of them. The variation in effectiveness of the two configurations in terms of the end-effector trajectory, end-effector accuracy and power consumption is discussed. Further, these configurations are optimized with respect to their performance accuracy, and compared to their pre-optimized versions. Further, the simulation is validated against with the physical hardware prototype, running the same task. A method of determining an optimal configuration based on a user-defined task is presented, in which the joint space of the MARS Manipulator is treated as a 12-dimensional smooth configuration manifold. The manifold is discretized and ranked based on a variety of criteria, and then clustered into attractive and repellent regions. The user then specifies which regions are desired in the target configuration, and the manifold is reduced in dimension in order to maximize the number of attractive regions and minimize the number of repellent regions. Six manipulators were synthesized using this approach, and their effectiveness is compared.Ph.D