Abstract:
The drilling process into rock has been modeled as a four-degree-of-freedom rock drill with a nonlinear rock model. Using direct numerical integration, the angular frequency and amplitude of the hydraulic force were employed as control parameters for bifurcation and basins of attraction analysis. The results showed that, when
ω<2.08, the model operated in the stick mode; when 2.08≤
ω≤6.5, the model operated in the non-stick mode. The period-3 solution exhibited greater global stability than periodic-1 and quasi-period solutions when 4.94≤
ω≤5.36. When 0<
a≤1, the stability of the periodic-1-2 solution increased with the amplitude, while the stability of the periodic-3 solution decreased. The basins of attraction of the period-1-1 solution increased at first and then became zero. A comparison of piston displacement and velocity data between the model and the experiment results revealed a strong correlation.