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This thesis is concerned with the application of a welding robot in a shipyard. It outlines the results and experiences gained from a research project on the application of a standard welding robot for small batch manufacturing. The theoretical work of this study was carried-out at the University, while all practical experiments were carried-out using a CM-T3-566 Industrial robot in a real shipyard environment. In particular, the concept of robotic welding for small batch manufacturing of minor steelwork and outfit items was practised and as a result the robot workcell was successfully taken to a production situation, producing components for ship and shipyard use. The experiments enabled a number of parameters that influenced the successful implementation of robotics on the shopfloor to be examined, while the feedback obtained opened and pointed the way for further robot applications in shipbuilding. The thesis begins by making the case for robots in shipbuilding and reviewing shipyard automation and robotic developments. The need for welding robots is then emphasised and the small batch manufacturing problem is explained. It then details the practical implementation of the welding robot and examines the lessons learned. The economic justification and areas for further development are also discussed. Finally, the expected future use of robots in shipbuilding is examined, describing a number of shipyard areas for robotisation and presenting the Flexible Automation in Shipbuilding Technology (FAST) concept, for advancing the use of robots from stand alone applications to Computer Integrated Manufacturing (CIM). The main conclusions are that robotic manufacture of small batches offers viable production benefits, that certain critical parameters exist which can enhance the effectiveness of robotic workstations and finally, that considerable scope still exists for further application of robotics, integrated with computer based manufacturing systems.

<p><b>Aims and Hypothesis</b>: The objective of this study was the design and testing of a Prototype Computer Numerical Control (CNC) dental handpiece. We predicted that the CNC Prototype would be more accurate than the human participant prosthodontists in clinical simulation. </p><p> <b>Materials and Methods</b>: A Prototype CNC dental handpiece was developed from off the shelf components, assigned 100 typodont teeth (#18) for submission and 10 practice teeth. Single operator. Five prosthodontists, given 20 typodont teeth (#18) for submission and 10 for practice. Finished preparations were scanned with 3M True Definition^&reg; intraoral scanner outside of typodont, compared with Geomagic Control for RMSE. </p><p> <b>Results</b>: RMSE Prototype (N=100) was 0.40mm. RMSE Prosthodontists (N=100) was 0.55mm. One sided T test, mean difference &minus;.15mm (p&lt;.001, one sided CI &minus;.09). One Way ANOVA (F stat &lt;1, F=.526, p=.717), Spearman correlation Prototype RMSE vs order(&rho;=.1, p=.334), RMSE vs Bur (&rho;=.36, p&lt;.001); For each prosthodontist individually (N=20) RMSE vs Order Prosthodontist 4(&rho;=&minus;.54, p= .015). Prosthodontist 5 (&rho;= .58, p = .022). Prosthodontist 3 (&rho;=.16, p=.498), Prosthodontist 2 (&rho;=&minus;.07, p=.772), and Prosthodontist 1 (&rho;=&minus;.08, p=.741) Spearman correlation (N=20) RMSE vs Bur Prosthodontist 5 (&rho;= .51, p = .007), Prosthodontist 2 (&rho;=.46, p= .040), Prosthodontist 4 (&rho;=&minus;.07, p=.758), Prosthodontist 3 (&rho;=.18, p=.445), and Prosthodontist 1 (&rho;=.43, p=.059) </p><p> <b>Conclusion</b>: CNC Prototype achieved superior results in clinical simulation, attained on a modest budget with a modest level of research support. Work should continue on the next iteration of a prototype to address some of the limitations of movement, feedback, and emotional acceptance of a machine performing treatment from the perspective of a patient. </p>

Robot calibration plays an increasingly important role in robot production as well as in robot operation and integration within computer integrated manufacturing or assembly systems. The production, implementation and operation of robots are issues where robot calibration results can lead to significant accuracy improvement and/or cost- savings. The thesis describes techniques for modelling, optimising and performing robot calibration processes using a 3-D vision-based measurement system for off-line programming. The identification of the nonrlnal kinematic model is optimised using numerical methods to eliminate redundant geometric parameters in the model. Calibration based on the optimised model shows improvement in robot accuracy when compared to the non-optimised model. The basics of the measurement system consist of a single CCD camera mounted on the robot tool flange, image processing software, and algorithms specially developed to measure the end-effector pose relative to a world coordinate system. Geometric lens distortions are included in the analytical technique. The target consists of two identical clusters of calibration points printed on photographic paper, and mounted on the sides of a 90-degree angle plate. Experimental work was performed to assess the measurement system accuracy at different distances from the camera to the target. An average accuracy from O.2mm to O.4mm was obtained at distances between 6S0mm to 9S0mm. Tests were also performed on three different robots to assess the improvement in the overall robot accuracy. The robots tested were: PUMA-SOO, IRB-2400 and IRB-6400. The errors before calibration for the three robots were approximately in a range from Smm to lSmm if measured in a large volume. The best average accuracy obtained after the calibration of the three robots was O.3Smm, O.60mm and O.4Smm respectively. This study shows that many different variables are involved in the calibration process. The influence of these variables was studied both experimentally and by means of simulation.

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The objective of the thesis is to compare and study recent visual grasping techniques which areapplied on a robotic arm for grasping of unknown objects in an indoor environment.The novelty of the thesis is that the study has led to questioning the general approach used byresearchers to solve the grasping problem. The result can help future researchers in investing more onthe problem areas of grasping techniques and can also lead us to question ourselves on the approachwe are using to solve the grasping problem.