It is difficult for three-dimensional （3D） depth information to be detected by monocular cameras， and there are limitations of binocular stereo vision when the surface features are not apparent. In addition， the proportional-integral derivative （PID） controller parameter tuning is not ideal. To address this， linear structured light technology is used to detect vibrations of the flexible manipulator， and the bacterial foraging algorithm is used to optimize the PID for vibration control. First， a linear structured light visual vibration measurement system is developed， and a mathematical model is established. Then， the visual calibration is completed， and the feasibility and accuracy of the proposed method are verified. By using the bacterial foraging algorithm， the parameters of the PID controller are optimized， the simulation results are compared with the results of the empirical tuning method， and the active vibration control experiment of the flexible manipulator is performed. Experimental results show that for the first-order modal vibration of the flexible manipulator， the average effect of the PID control method based on the empirical method control is 25.65% compared with the average effect of 39.32% when using the bacterial foraging algorithm. Consequently， the superiority of the proposed bacterial foraging algorithm when optimizing PID controller parameters is demonstrated.