A novel hybrid algorithm named ATM-CMAES, which integrated covariance matrix adaptation evolution strategy (CMAES) with adaptive tradeoff model (ATM), was proposed to solve constrained optimization problems. CMAES in the new algorithm used the relationship between the best subgroup of the current generation and the mean of the previous generation to update covariance matrix. Compared to traditional evolutionary algorithm, CMAES needed smaller evolving population size since it combined rank-1 with rank-μupdate mechanism in the update process of covariance matrix. ATM was introduced as constr...