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This work is focused on reactive Static Obstacle Avoidance (SOA) methods used to increase the autonomy of Unmanned Surface Vehicles (USVs). Currently, there are multiple approaches to avoid obstacles, which can be applied to different types of USV. In order to assist in the choice of the SOA method for a particular vessel and to accelerate the pretuning process necessary for its implementation, this paper proposes a new AutoTuning Environment for Static Obstacle Avoidance (ATESOA) methods applied to USVs. In this environment, a new simplified modelling of a LIDAR (Laser Imaging Detection and Ranging) sensor is proposed based on numerical simulations. This sensor model provides a realistic environment for the tuning of SOA methods that, due to its low load computation, is used by evolutionary algorithms for the autotuning. In order to analyze the proposed ATESOA, three SOA methods were adapted and implemented to consider the measurements given by the LIDAR model. Furthermore, a mathematical model is proposed and evaluated for using as USV in the simulation enviroment. The results obtained in numerical simulations show how the new ATESOA is able to adjust the SOA methods in scenarios with different obstacle distributions.

The detailed study of the turbulence and the fluid flow in sport is an open and exciting field of research, in particular in swimming and aquatic sports there is a wealth of new techniques that may aid performance. In swimming, thanks to measurement techniques like Particle Image Velocimetry (PIV), Particle Tracking (PT) or pattern analysis, now it is possible to measure the flow environment and not just the human movement. Numerical Computational Fluid Dynamics (CFD) is also a useful tool. We present several techniques stressing the importance of 3D effects and the dynamics of enhanced propulsion by hands and feet while the reduction in resistance need to be considered in an integrated way. Examples of Sculling, Hand wakes, Underwater Undulatory Swimming (UUS) and Vortex Filament Analysis (VFA) are all interesting to improve swimming techniques.

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