Regenerative and frictional chatter in plunge grinding

Abstract

This paper studies self-excited vibrations, regenerative and frictional chatters, in a plunge grinding process. In consideration of lateral and torsional workpiece movements, a dynamic model with four degrees of freedom is proposed, which involves statedependent time delays and Stribeck effect for regenerative and frictional effects, respectively. With this model, by linearising contact angle, regenerative grinding depth, frictional velocity and the state-dependent delays, eigenvalue analysis yields stability diagrams for the grinding, where boundaries for both regenerative and frictional instabilities are determined. Then, near the boundaries, simulations and bifurcation analyses are performed to reveal patterns of chatter onset. Bifurcation diagrams show coexistence of stable grinding and the regenerative chatter near the regenerative boundary, and a sudden switch between the stable and the frictionally unstable on the frictional boundary. Moreover, simulation results also show various dynamical properties in the grinding chatters, such as effect of losing contact and stick-slip motion.

Chatter detection in milling processes—a review on signal processing and condition classification

“…Hence, it is meaningful to study the tool wear effect on chatter occurrence and detection. Tool wear has been studied and modelled for frictional chatter, and some researchers reported how this issue affects the dynamics greatly in metal cutting [380][381][382][383], while the coexistence of regenerative and frictional chatter has been studied and recently modelled by Yan et al [384][385][386] and Weremczuk et al [387], and the no co-occurrence of mode coupling and regenerative chatter is reported by Celikag et al [388]. Similarly, Matsumoto et al [389] and Stavropoulos et al [390] concluded that chatter reduces TCM accuracy.…”

Nonlinear dynamics of lump mass model of drill-string in horizontal well

“…Case III: Drilling with Disk 1 and Disk 2 as an integral part. Compared with the previous two cases, the most immediate improvement is that the coupled axial-torsional vibration of the drill-string system is simulated by considering the regenerative cutting effect of the drill-bit, which are similar to metal machining [37][38][39]. Due to the complexity and high nonlinearity arising from the varying time delay, even a constant driving rotation speedφ t would excite excessive vibration, so that a constantφ t is employed in this case.…”

Static and dynamic post-buckling analyses of irregularly constrained beams under the small and large deformation assumptions

“…The normalized projection of the deformed beam in the longitudinal direction, D, can be calculated as (17) where the relationships between the rotation angle, , and the displacements in X and Y directions are defined as (18) and the non-dimensional factors are (19) Thus, the normalized deformation in x direction yields,…”

“…Liu and Chen [16] theoretically studied the effect of Coulomb friction on the buckling behavior of an elastica that was constrained in a straight channel with clearance. The friction-induced vibrations were theoretically investigated by Saha et al [17] and Yan et al [18]. The governing equations in those studies were solved based on the equilibrium conditions and geometric compatibilities.…”