Fused Deposition Modelling (FDM) is one of the most popular 3D printing technologies because of its affordability and accessibility. FDM, however, often suffers from printing errors that result in wasted time, materials and energy. To address these challenges, this thesis introduces a novel fault detection system for FDM printers. This system is designed to identify a broad range of errors without interrupting the printing process. To achieve a real-time detection system, an innovative multi-camera setup is designed, integrating two side cameras and one nozzle camera. Our hypothesis is that a system including three cameras can provide a more comprehensive view and can ensure more error types to be detected. Error detection is achieved using Convolutional Neural Networks (CNNs). This is a type of machine learning that excels at image recognition and pattern detection, making it well-suited for identifying printing errors in real-time models. Two CNN models are developed to classify images into common 3D printing errors: one model for the nozzle and another for the side cameras. The models were trained and validated on diverse datasets containing various shapes, infills, and augmented data. The nozzle camera model achieved a high validation accuracy of 97.68% with a low loss of 0.07464. The side camera model achieved comparable performance with a validation accuracy of 97.61% and validation loss of 0.1196. These two well performing models were for the first time ever integrated into a unified fault detection system based on a logic-driven priority framework. From this research, we learned that integrating multiple viewpoints into a logic-driven priority framework significantly improved the robustness of error classification, as many more error types could be detected in-situ and real-time. As a result, the integrated system successfully detected 12 common printing errors. In summary, this work shows the feasibility of developing a robust multi-input fault detection system to improve 3D printing. It paves the way for further research and implementation for complex integrated error detection and correction mechanisms.

Bush planes are general aviation aircraft, that enable transportation to remote areas, where there is no infrastructure supporting regular aviation. Their main features are the taildragger configuration, a short take off and landing distance (STOL) and they offer the ability to land on rough terrain. Paradoxically, although they are the aircraft most directly related to nature, bush planes are often old, polluting and loud, and thus far from being environmentally friendly. To partially overcome these disadvantageous characteristics, Group 12 designed a stateoftheart bush plane, using the principle of distributed propulsion, called the Twin Puffin. In order to design a bush plane, first an understanding is required of the needs and desires of the stakeholders. For this, a market analysis is performed and from this it can be concluded that the aircraft will serve for three main purposes: transport, medical emergency missions and tourism. After obtaining the insight into the market of bush planes, all possible design options are listed. Pruning of unfeasible, unrealistic and inapplicable options is done to end up with seven aircraft concepts. From those concepts, the most suitable and promising is then selected. The aircraft is chosen to be a twin boom concept, therefore the name Twin Puffin was chosen for the design. Following, the design is worked out in detail, where all the subsystems are designed. The fuselage, the structure of the plane, the energy source, the wing, the propulsion system, the empennage, landing gear and electrical systems are designed and optimised, so the final aircraft design is finalised. Inspired by Nature, the bush plane is named the Twin Puffin. ’Twin’ following the distinctive twinboom empennage, and the ’Puffin’, from the bird with a stubby display and a master of short takeoff and landing on the ocean cliffsides, a real inspiration for a STOL aircraft. The featured twin boom empennage make aft loading of cargo or a medical stretcher easy. Furthermore, the distributed propulsion is placed on the wing’s leading edge, allowing unobstructed view during all flight phases, solving the typical visibility issues of a traditional bush plane. The distributed propellers are powered by a hybrid engine using both electricity from batteries and power generated by an internal combustion engine that can run on diesel, jet fuel, and suitable types of biofuels. This allows for an increase in available power and a local reduction in the emissions and noise during electricallypowered takeoff and landing. Furthermore, the distributed electric propulsion lead to excellent STOL characteristics, as the blown air over the wing allow for a large increase in lift at low speeds. Moreover, the Twin Puffin is primarily built of the sustainable material flax fibre composite, making the aircraft more environmentally friendly. The Twin Puffin is estimated to produce 70% less noise and 50% emission, compared to competing aircraft and is thereby a modern, impressively performing bush plane design.