A fundamentally precise and simple linear motion axis design is discussed where the attractive force from the linear motor is used to preload a carriage supported by six rigidly attached porous carbon air bearings. The air bearings are assembled by vacuuming the pads to two orthogonal planes, positioning the carriage above the pads, and then injecting epoxy between the bearings and the carriage...

Hydrodynamic and aerodynamic lubrication regimes in their controllable forms have been intensively investigated over the last two decades. With the aim of reducing friction and improving thermal, static, and dynamic characteristics of radial sliding bearings, different types of electro-mechanical actuators have been coupled to such bearings. Depending on (i) the actuator type; (ii) the actuatio...

For the purpose to facilitate development of high-speed Spindle Units (SUs) running on rolling bearings, we have developed a beam element model, algorithms, and software for computer analysis of thermal characteristics of SUs. The thermal model incorporates a model of heat generation in rolling bearings, a model of heat transfer from bearings, and models for estimation of temperature and temper...

This paper reviews the design and validation of a novel bearing test rig developed at the KU Leuven. The test rig allows multi-axial static and dynamic loading of a rolling element bearing. Different types and sizes of bearings can be mounted and loaded as if built into a real machine. The test rig will be used to analyse the effect of external dynamic loads on the lifetime of these bearings. T...

Surgeons remain concerned that ceramic hip prostheses may fail catastrophically if either the head or the liner is fractured. We report two patients, each with a ceramic-on-ceramic total hip replacement who sustained high-energy trauma sufficient to cause a displaced periprosthetic acetabular fracture in whom the ceramic bearings survived intact. Simultaneous fixation of the acetabular fracture...

Bearings are one of the most critical components in many industrial machines. Predicting remaining useful life (RUL) of bearings has been an important task for condition-based maintenance of industrial machines. One critical challenge for performing such tasks in the era of the Internet of Things and Industrial 4.0, is to automatically process massive amounts of data and accurately predict the ...

This paper addresses the two-dimensional (2D) direction-of-arrival (DOA) estimation problem with two novel methods for mixed noncircular and circular signals. The first proposed method is named the two-stage direction-of-arrival matrix (TSDOAM) method, and the other is called the two-stage rank reduction (TSRARE) method. The proposed methods utilize both the circularity and the direction-of-arr...