Tham khảo tài liệu 'manufacturing the future 2012 part 11', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Evolutionary Optimisation of Mechanical Structures or Systems 491 plane of the plate is a great deal weaker. This part treats the stiffening of plate structures with the addition of beam supports. Essentially the aim is to optimise the positioning of the supports with the objective being the yield perpendicular displacement to mean plane of the sheet this procedure can bring about interesting improvements in a structure behaviour. One uses a genetic algorithm to optimise the position of a series of supports of equal lengths precisely on a plate in bending. The plate studied in this example had dimensions of m long by m wide. The plate was completely embedded along one of it s width and was made of steel of elastic modulus E 104 DaN mm2 and Poisson s ratio . It was 2 mm thick figure 11 . The supports were made from the same material as the plate and were completely integrated. They have a drop height of 8 mm and a width of 5 mm . 34 1y 9 39 13 40 17y .1J _ 1 1 _ 2 44 6V 1 14 14 47 1848 I-I _ 371 - w n 15 4 1955 1 1 . 1 - - 1 1 I-I - 1 1 nr nr nr 16 61 20 62 49 24V F F 28 Figure 11. Numeration of the plate supports 5 mm Figure 12. Cross-section of the plate and support 492 Manufacturing the Future Concepts Technologies Visions The plate is held horizontal by being embedded along one of it s width. At the opposite end two identical forces of 144 DaN are applied vertically. In this example the overall mass of the structure is not taken into account. So our objective here is to reduce the maximum bending of the plate while optimising the positioning of a number of stiffeners. The maximum bending is the greatest vertical displacement of the plate. The element distribution represented on figure 11 shows that there are 525 possible positions for the stiffeners each 100 mm long. Such a large domain of research requires a huge calculation time so in order to reduce this the number of possible positions is reduced and regrouped such that a support is made of .