Dynamic response errors and accuracy reliability for mechanism with multiple lubrication clearance joints

In mechanical industry, most mechanical systems contain lubrication clearance joints. Consequently, to analyze the dynamic response errors and accuracy reliability for mechanisms with lubrication clearance joints is very necessary. So far majority studies have focused on kinematic accuracy reliability for mechanism, but few on dynamic response errors and accuracy reliability. Moreover, the only studies on dynamic accuracy reliability mainly focus on mechanisms with dry contact clearance joint, while the studies on dynamic accuracy reliability for mechanisms with lubrication clearance joint are very few. This paper presents an analysis method of dynamic response errors and accuracy reliability for mechanism with lubrication clearance joints. Firstly, the lubrication clearance joint model and dry contact clearance joint model are established, respectively. The dynamic model of nine-bar mechanism with multiple lubrication clearance joints is developed according to Lagrangian multiplier method. And then, the dynamic accuracy reliability model for mechanism is derived by first-order second-moment method. Finally, the influences of lubrication clearance and dry contact clearance on dynamic response errors and accuracy reliability for mechanism are compared and analyzed at different driving speeds. And the influences of dynamic viscosity and clearance values on dynamic response errors and accuracy reliability for mechanism with lubrication clearance joints are researched. This research offers the theory foundation for design of reliability for mechanism.