نوع مقاله : مقاله پژوهشی
دانشکده ی مهندسی مکانیک، دانشگاه آزاد اسلامی واحد علوم و تحقیقات تهران
عنوان مقاله [English]
This research aims to minimize the weight of truss structures using force method formulation as a structural analyzer and Jaya algorithm as an optimizer tool. Constraints considered herein include stress limitations, displacement limitations, and size limitations. Design variables include the cross-sectional area of each element. They may easily be related to each other which will lead to decrease of design variables.
Jaya algorithm is a meta-heuristic random search method recently developed for constrained and unconstrained problems. The main superiority of Jaya algorithm to other random search methods is that it does not need any specific tuning parameter to generate next population. This algorithm consists of two steps in each cycle. First, a new population is generated using a simple random formula. Second, each new point is compared to its corresponding previous one while penalty function method is implemented. If the new point is in a better condition than the old one, the old one is replaced by the new one. All points are tested similarly till the population is updated. The procedure is repeated so as to achieve the desired convergence.
Several landmark examples appearing in the literature have been solved by the proposed method, thus showing the efficacy of the developed procedure. A perusal of results shows that procedure is not sensitive to the starting points and it should just be selected large enough to lie in feasible-usable design space. Moreover, rapid reduction of weight is obtained in the first few steps and the tendency of decreasing of the weight appears to be monotonic and uniform in all examples.
Unlike other metaheuristic methods that need a large number of optimization cycles to settle near the optimum point, combination of force method and Jaya algorithm provides higher computational efficiency and rapid convergence ability achieved by the above match. This is owing to the forced method formulation that makes the stress constraints to be linear, resulting in facilitating the procedure and enhancing its efficiency.