A new method combined a floating-point encoding genetic algorithm with dynamic penalty function is solved the constraint problems
and migration strategy is introduced in the genetic algorithm to speed up the search of the global optimal solution.Besides
the improved genetic algorithm is applied to reliability optimization design of NGW planetary gear transmission.It is showed that the ability to search the global optimal solution of improved genetic algorithm in the feasible region is superior to the conventional optimization design method.Therefore
the size parameters of the planetary gear are improved