Multiple tori intermittency routes to strange nonchaotic attractors in a quasiperiodically-forced piecewise smooth system

The multi-torus intermittent paths of strange nonchaotic attractors in quasi-periodic forced piecewise smooth systems are investigated. Due to Farey tree bifurcations, different tori are converted to intermittent strange nonchaotic attractors through a series of non-smooth saddle-node bifurcations. First, the singularity is observed by the phase diagrams, and then the non-chaos is determined by calculating the maximum Lyapunov exponent. In addition, some properties of SNAs can be described by analyzing the variation of phase sensitive function with the number of tori, the structure of recursive plot and finite time Lyapunov exponential distribution. What is different from previous studies about SNAs is that the distribution of the finite-time Lyapunov exponents peaks at extremely negative values, while the positive tail of the distribution decreases in a linear manner.