Theoretical expressions are derived relating amplitude and wavelength of surface imperfections in thrust loaded ball bearings to vibration forces and frequencies produced under constant-speed operating conditions.

Experimental vibration measurements of a system containing a single ball bearing are compared with theoretical predictions based upon the model described in Part 1 and measurements of system transfer functions. Agreement between theory and experiment is reasonable.

Currently the underlying necessities for predictability, producibility and productivity remain big issues in ultraprecision machining of miniature/microproducts. The demand on rapid and economic fabrication of miniature/microproducts with complex shapes has also made new challenges for ultraprecision machine tool design. In this paper the design for an ultraprecision machine tool is introduced by describing its key machine elements and machine tool design procedures. The focus is on the review and assessment of the state-of-the-art ultraprecision machining tools. It also illustrates the application promise of miniature/microproducts. The trends on machine tool development, tooling, workpiece material and machining processes are pointed out.

High accuracy three dimensional miniature components and microstructures are increasingly in demand in the sector of electro-optics, automotive, biotechnology, aerospace, and information technology industries. A rational approach to mechanical micro machining is to develop ultraprecision machines with small footprints. In part 1 of this two-series paper, the state of the art of ultraprecision machines with micro machining capability is critically reviewed. The design considerations and specifications of a 5-axis ultraprecision micro milling machineUltraMill are discussed. Three prioritized design issues: motion accuracy, dynamic stiffness and thermal stability formulate the holistic design approach for UltraMill.This approach has been applied to the development of key machine components and their integration so as to achieve high accuracy and nanometer surface finish.

Ultraprecision machines with small footprints or micro-machines are highly desirable for micro-manufacturing high-precision micro-mechanical components. However, the development of the machines is still at the nascent stage by working on an individual machine basis and hence lacks generic scientific approach and design guidelines. Using computer models to predict the dynamic performance of ultraprecision machine tools can help manufacturers substantially reduce the lead time and cost of developing new machines. Furthermore, the machine dynamic performance depends not only upon the mechanical structure and components but also the control system and electronic drives. This paper proposed a holistic integrated dynamic design and modelling approach, which supports analysis and optimization of the overall machine dynamic performance at the early design stage. Based on the proposed approach the modelling and simulation process on a novel 5-axis bench-top ultraprecision micro-milling machine tool – UltraMill – is presented. The modelling and simulation cover the dynamics of the machine structure, moving components, control system and the machining process, and are used to predict the overall machine performance of two typical configurations. Preliminary machining trials have been carried out and provided the evidence of the approach being helpful to assure the machine performing right at the first setup