A novel control mixer method for reconfigurable control designs is developed. The proposed method extends the matrix-form of the conventional control mixer concept into a linear time invariant dynamic form. The H_infin control technique is employed for dynamic module design after an augmented control system is constructed through a model-matching strategy. The stability, performance and robustness of the reconfigured system is shown to be guaranteed when some conditions are satisfied. A robot system subjected to faults is used to demonstrate the reconfiguration procedure and illustrate the effectiveness of the proposed method.