Abstract3D fabric preforms are used as reinforcements in composite applications. 3D woven preforms have a huge demand in ballistic applications, aircraft industry, automobiles and structural reinforcements. A variety of 3D woven fabric reinforced composites and two dimensional woven fabric reinforced laminates can be found in the literature. However, the majority of the said products lack in delamination resistance and possess poor out-of-plane mechanical characteristics, due to the absence or insufficiency of through-thickness reinforcement. 3D fully interlaced preform weaving introduces a method of producing fully interlaced 3D woven fabric structures with through-thickness reinforcement, which enhances the delamination resistance as well as out-of-plane mechanical characteristics. 3D woven fabric preforms made from 3D fully interlaced preform weaving, using high-performance fiber yarns such as Dyneema, Carbon, Kevlar and Zylon, have exceptional mechanical properties with light-weight characteristics, which make them suitable candidates for high-end technical composite applications. In this work, a brief introduction is given to the history of weaving followed by an introduction to 3D woven fabrics. In the existing literature, an emphasis is given to the 3D fully interlaced preform weaving process, distinguishing it from other 3D woven fabric manufacturing methods. Subsequently, a comprehensive review is made on the existing literature on 3D fully interlaced preform weaving devices, such as primary and secondary mechanisms as well as modelling of 3D woven fabric structures produced by 3D fully interlaced preform weaving. Finally, the authors attempted to discuss the existing research gaps with potential directions for future research.

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Unmanned aerial vehicles or drones are becoming one of the key machines/tools of the modern world, particularly in military applications. Numerous research works are underway to explore the possibility of using these machines in other applications such as parcel delivery, construction work, hurricane hunting, 3D mapping, protecting wildlife, agricultural activities, search and rescue, etc. Since these machines are unmanned vehicles, their functionality is completely dependent upon the performance of their control system. This paper presents a comprehensive approach for dynamic modeling, control system design, simulation and optimization of a quadcopter. The main objective is to study the behavior of different controllers when the model is working under linear and/or non-linear conditions, and therefore, to define the possible limitations of the controllers. Five different control systems are proposed to improve the control performance, mainly the stability of the system. Additionally, a path simulator was also developed with the intention of describing the vehicle’s movements and hence to detect faults intuitively. The proposed PID and Fuzzy-PD control systems showed promising responses to the tests carried out. The results indicated the limits of the PID controller over non-linear conditions and the effectiveness of the controllers was enhanced by the implementation of a genetic algorithm to autotune the controllers in order to adapt to changing conditions.

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