Conceptual Design, and Fluid-Structural Interaction Based Investigations on Highly Maneuverable Unmanned Amphibious Vehicle for Ravage Removal Applications at Various Oceanic Working Environments

10 Nowadays Unmanned Amphibious Vehicles [UAVs] are employed in many applications such as oceanic 11 research, deep sea exploration, mapping, naval surveillance, and disaster monitoring and fisheries protection. The 12 use of UAVs in military and other applications has steadily increased over the few years. On the other hand, there 13 has been a tremendous increase in ocean exploitation. Though technologies are increasing incrementally, nature is 14 exploited adversely. Advancement in ocean transportation, shipping, sewage wastes filled the ocean with tonnes and 15 tonnes of debris and oil wastes. This ravage fills affect the complete marine ecosystem. This in turn makes the ocean 16 toxic. Advancements have been made in recent years to clean up the oil spills. The noted projects such as Sea bin, 17 super high-tech sponges etc. All these innovations are the static one which cannot move along the waves of the 18 ocean. The static form of these inventions could not be used to clean to the larger extent. Therefore, this study aims 19 to build an UAV which is a movable one, can detect the debris and clean those by incorporating existing cleaning 20 techniques. Since the UAV has to sub merge under the water to some extent, it should be designed in such a way by 21 considering both the hydro-dynamical and hydro structural aspects of it. The unique point in the paper covers the 22 flexible cum efficient design of the UAV. The design of the tropical bird is chosen for the efficient model of the 23 UAV. With the few known parameters of this species, the UAV has been designed to achieve the maximum 24 efficiency. The tropical bird chosen has the higher rate of climb, which is the desired requirement for this study. The 25 propeller is uniquely designed based on aerodynamic cum hydrodynamic data


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on the above said analysis the weight of the launcher and the remotely operated vehicle were reduced according to 148 the safety factor and stress obtained. The safety factor for the maximum stress for the optimum design is about 8.

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From the paper it is found that the Ti alloy and Al alloy are considered as the suitable material for the pressure   completed. To verify the depth and heading control simulation, free running tests were carried out in a towing tank.

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The paper provides an idea for structure analysis, and the methods of simulations.

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The wingspan of the UAV is taken from an adult tropic bird wing. In general, the Aspect Ratio (AR) of long-193 range UAV is should be more than 15 and medium velocity UAVs aspect ratios are varying 8 to 15. For this case the 194 UAV works in medium velocity. As per the historical relation the aspect ratio was fixed. Using aspect ratio and 195 wing span the wing area was estimated using following formula. From historical relation the wing loading was fixed 196 and using those total weights is estimated.
Likewise, from historical relation the taper ratio for forward and backward swept wing was estimated.

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The wing consists of two parts, a rectangular wing that is forward swept wing and a tapered wing that is the 209 backward swept wing. The forward swept wing helps to maintain the airflow over their surfaces at steeper climb 210 angles than conventional plane. The swept back wings give the more lateral stability and less turbulence when speed 211 abruptly changes. From the literature survey, it is found that 40% of wingspan is allocated for forward swept wing 212 and 60% of the wingspan is allocated for backward swept wing. The half of the wingspan is equal to 48 cm, in 213 which, 40% is allocated for first portion, which is 19.2 cm and 60% is collocated for second portion, which is 28.8 214 cm.

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The relationship between Wingspan, chord length, and Wing Area,

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C wing−root = 921.6 96 = 9.6 cm 219 From the Tropic Bird, the primary design details about first taper ratio is obtained, which slightly tilted forward 220 swept wing.

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Form the literature survey, it is found that λ = 0.4 is more suitable to provide low drag with high lift at 227 positive angle of attack, therefore in this work λ = 0.4 is used At 25% of span of both the side, At 50% of span of both the side, 242 C 50% = 7.45 cm  268 269 Thrust at 5 m/s = 20.184 N andThrust at 10 m/s = 83.25 N 270  Table 1.

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The NACA 2408 aerofoil is selected as best than others based on low co-efficient of drag value. Thus, 296 through the help of obtained design data, the conceptual designs of UAV and its propeller are modeled. The

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conceptual design of propeller is revealed in Figures 1 and 2 The estimated values for wing dimensions are tabulated in Table 2.

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The deformation, equivalent stress, and normal stress over a UAV are the major outcome these FSI analyses.

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The lift force is little higher than required amount. Reason for that is the span of the wing. Then the drag force is 456 acceptable. Using that value, the rpm of propeller fixed. Because then only it can overcome that drag force.

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Additionally, the side force also estimated for general purpose.  fluctuations. This will also make them denser and so they become less buoyant. These oil spills will bring adverse 542 effects for the society. Unfortunately, the fact is that cleaning the oil spills is a difficult task and it depends on many 543 factors such as the type of oil that is spilled, the water temperature, the type shoreline, the type of beaches/ocean 544 involved etc. Cleaning the oil spills physically is so expensive. The method of bioremediation using bacteria is a 545 better method, but only to some extent, since abundant bacteria is needed and also this method requires the external factor to support. The Seabin project can also be a possible solution but that is the static model. Similar to these 547 techniques fewer advances have made to clean up the oil spills but that was not cost efficient. By considering all 548 these factors an idea come up with a solution of having a dynamic movable model, which is capable of locating the 549 debris and also clean up such spills. The dynamic movable model is the UAV which proves to be the possible  performer. Then, the next FSI analysis is carried out on UAV under the Ocean at the depth of 5 m and so the suitable 574 material is picked to resist such kind of environment. At last, it is strongly Overall the required UAV has been 575 conceptually modeled to meet the ravage removal application. One major observation is found that GFRP-Woven-

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FR4 based composite material is best lightweight material to resist all kinds of oceanic environments thus the same 577 material is strongly suggested for the implementation in UAV's real time application. The designed UAV is capable 578 of providing good conditions for the cleaning mechanism to take place. Bio-inspired structure of the UAV when 579 modeled gives extraordinary support for the ravage removal. This will set the base for the inventions in ravage 580 removal.

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There is no any external and internal funding sources are available for this manuscript SKM -SKM is the main author to finalize this innovation approach on UAV and did Literature Survey.