Study on Stiffness and Positioning Accuracy of Active Fixing Cylinders for Thin Plate Machining

This study evaluated the stiffness and positioning accuracy of active fixing cylinders for thin plate machining. We integrated ball screws and servo motors into the active system to enable real-time adjustments and dynamic control. The axial stiffness decreased due to the complex assembly of components, and the radial stiffness was similar to that of a passive cylinder but rapidly decreased as the setting height increased. For an active cylinder to have high stiffness, structural design improvements, such as assembly tolerances between the cylinder and bushing and preload of the ball screw, were necessary. The active setup demonstrated superior performance in positioning accuracy, achieving precisions of 8 and 4.3 μm over 450 and 50 mm ranges in the horizontal and vertical setups, respectively. These findings highlight the potential of active systems in high-precision applications, particularly aerospace, where they offer better adaptability and precision over conventional methods.