Dynamical behavior of redundant thrusting mechanical system in shield machines with various grouping strategies

Abstract

The thrusting system of shield machines is consisted of multiple hydraulic cylinders which are usually divided into four groups. The dynamical behavior of shield is closely dependent on the grouping strategies. In this context, the thrusting system is equivalent as a redundant actuating parallel mechanism. Two grouping strategies are used as 4147 and 4345 for sixteen hydraulic cylinders. The dynamical model of shield was established by using Newton-Euler method. The dynamical behavior is investigated considering the two grouping methods. The results show that the fluctuations of velocities and displacements of shied are obviously different for the two grouping strategies when the fraction of soft soil on the excavating face is changed. The grouping strategies should be determined based on the complex geological structures in order to reduce the blockage accidents. © 2013 Springer-Verlag Berlin Heidelberg.