The paper develops a new measurement system based on computer visual feedback and adopts the nonlinear control method for measuring and controlling the synchronization error of dual-cylinder-group electro-hydraulic system in the pushing railway bridge machinery. According to theory of computer visual feedback, a new kind of model of measurement system and the algorithm of transformation of coordinates is proposed to detect the bridge's position and attitude with the adoption of CCD sensors and image-processing on real-time. A kind of dual-loop controller is designed by modifying conventional PID controller. The simulation results verify the effectiveness of the conclusions.