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Positioning speed and precision control of a segment erector for a shield tunneling machine

This paper deals with a positioning speed and precision control system for the assembly of segments of a shield tunneling machine. First, we design a six degrees of freedom segment erector with electrohydraulic drive. Then, the segment positioning process and the dynamics model of the electrohydraulic system are analyzed theoretically. Segment positioning control system is designed, making comparisons between speed and displacement/angle control in terms of efficiency and precision. Several reference speed run curves are selected to control the segment positioning process. Simulations are carried out to achieve the selected optimal run speed of the segment. The simulation results verify the validity of the proposed control system.