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Rotary-percussive drilling is a hybrid technique which combines the rotation and the percussion of a drillbit to break rocks. This technique is expected to have the advantages of both percussion and rotation to enhance the drilling efficiency. In order to well control the rotary-percussive drilling, the rock contact law under intermittent impacts from a drillbit should be fully understood. In the present work, linear and nonlinear drillbit-rock interactions which are integrated into a drillbit-rock vibro-impact system (see Fig.1) are compared. A Matlab computational suite, ABESPOL which is developed based on the computational continuation core (COCO), is used to conduct numerical integration and numerical continuation. Excitation frequency, excitation amplitude, and static force (see Fig.2) are set as the control parameters to carry out bifurcation analyses. According to the numerical results, the basic dynamic responses and the evolutionary process between the linear and nonlinear interactions are similar; their main difference comes from the scope of chaos.