Presence of dry friction and clearance discontinuities in various dynamic systems, such as friction wedge dampers in a three-piece railway freight-vehicle bogie, centre buffer coupler connecting two coaches, originate significant jerks. While nonlinear dynamics of systems, with these individual and combined discontinuities has received some attention, behavior of jerks remains unexplored. This study investigates the stick–slip effects and sources of jerks in such systems, using a representative single degree of freedom system, featuring simultaneous presence of dry friction and clearance, subjected to harmonic excitation. Den Hartog’s analytical formulations Hartog (1930) of friction mode transitions are extended numerically, to include the combined effect of dry friction and clearance, for investigation of stick–slip and jerk characteristics. It is shown that jerks can be distinguished between those arising from stick–slip effects due to dry friction and those from soft spring impacts. Limiting values of the ratio of friction force to excitation force for stick–slip motion are obtained. These frequency dependent ratios are larger than those in systems with friction alone. Multiple-stick–slip events, within a cycle, are observed at lower excitation frequencies. At higher frequencies, instances of high amplitude jerks are more than at lower excitation frequencies. A parametric study is carried out with a view to obtain the optimum range of design parameters for jerk minimization. Effects of wear and tear on jerks have also been considered through modeling of deteriorated system parameters.

各种动态系统中存在干摩擦和间隙不连续性，例如三件式铁路货运车辆转向架中的摩擦楔形阻尼器、连接两节车厢的中央缓冲耦合器，会产生明显的冲击。虽然系统的非线性动力学，具有这些单独的和组合的不连续性已经受到一些关注，但混动的行为仍未得到探索。本研究使用具有代表性的单自由度系统研究此类系统中的粘滑效应和急动的来源，该系统具有同时存在的干摩擦和间隙，受到谐波激励。Den Hartog 的摩擦模式转换分析公式 Hartog (1930) 在数值上进行了扩展，包括干摩擦和间隙的组合效应，用于研究粘滑和加加速度特性。结果表明，可以区分由干摩擦引起的粘滑效应和软弹簧冲击引起的急动。获得了粘滑运动的摩擦力与激振力之比的极限值。这些与频率相关的比率大于仅具有摩擦的系统中的比率。在较低的激励频率下观察到一个循环内的多次粘滑事件。在较高频率下，高振幅抖动的情况比在较低激励频率下更多。进行参数化研究，以获得最小化加加速度的最佳设计参数范围。通过对恶化的系统参数进行建模，还考虑了磨损对加加速度的影响。