Assembly of segments for shield tunnel excavation system using task-oriented force control of parallel link mechanism

In this paper, we are going to propose a task-oriented force control system for the assembly of segments of a shield tunnel excavation system. First, we design a generalized coordinate system referred to a task-oriented coordinate system, so that the position and orientation of a segment will be adjusted compliantly according to the external force from existing segments with which the segment is assembled together. A hybrid position/force control algorithm is then designed for a parallel link mechanism with hydraulic actuators. The system is experimentally applied to the assembly of segments of honey-comb shape. The experimental results illustrate the validity of the proposed system