A study on dynamics of flexible multi-link mechanism including joints with clearance and lubrication for ultra-precision presses

Abstract

It is essential to establish a dynamic model of flexible multi-link mechanism with clearance and lubrication for ultra-precision presses to analyze its dynamic response. Traditional dynamic models of mechanical system rarely consider the effect of flexibility, revolute and spherical clearance joints, and lubrication together, which causes lower precision analysis. In order to study the dynamic characteristics of multi-link mechanism more accurately, a novel dynamic model of flexible multi-link mechanism with clearance and lubrication for ultra-precision presses is established in the present work, which considers the effect of revolute and spherical clearance joints, lubrication, and flexibility of crank shaft and linkage. It is demonstrated that the dynamic responses of flexible multi-link mechanism with lubricated clearance joint model agree better with experimental data than those with dry clearance model and the validity of the proposed model is verified. The simulation results also show that the existence of lubrication reduces the dynamic responses of flexible multi-link mechanism with revolute and spherical clearance in a significant manner and act as a suspension for multi-link mechanism.

Stabilization of stochastic Markovian switching systems on networks with multilinks based on aperiodically intermittent control: A new differential inequality technique

“…For system (13), let N = 13, l = 3,  = {1, 2}, the elements of generator ( ks ) 2×2 are as follows: 11 = −1, 12 = 1, 21 = 0.5, 22 = −0.5. Table 1.…”

Analysis of the joint clearance effects on a compliant spatial mechanism

“…Secondly, when the contact between the two bodies occurs, the contact-impact forces are modelled according to a non-linear dissipative force model based on the Hertzian contact theory (normal force, F N ) together with the Coulomb's friction law (tangential force, F T ). These two conditions can be expressed as [9,19,44] when the magnitude of the clearance vector is greater than radial clearance, an impact occurs and the penetration depth is calculated by Eq. (2).…”

“…The influence of friction-induced vibration on the predicted wear of hard hip arthroplasties was also studied [18]. Except for compliant theme, some studies [19][20][21][22][23][24][25][26] were implemented to investigate the effects of link flexibility on the mechanism having clearance joint. Additional effects of joint having multiple clearances to the mechanisms' outputs [27][28][29][30] were also performed by considering planar and/or spatial mechanism models having different joint types.…”

Dynamic Responses of Planar Multilink Mechanism considering Mixed Clearances

“…Planar multilink mechanisms are widely applied in engineering, such as mechanical press, agricultural equipment, medical apparatus and instruments, and precision instrument [1][2][3][4]. Translational and revolute joints are important parts to connect each component of planar multilink mechanisms.…”