Ultra-precision grinding is primarily used to generate high quality and functional parts usually made from hard and difficult to machine materials. The objective of ultra-precision grinding is to generate parts with high surface finish, high form accuracy and surface integrity for the electronic and optical industries as well as for astronomical applications. This keynote paper introduces general aspects of ultra-precision grinding techniques and point out the essential features of ultra-precision grinding. In particular, the keynote paper reviews the state-of-the-art regarding applied grinding tools, ultra-precision machine tools and grinding processes. Finally, selected examples of advanced ultra-precision grinding processes are presented.

Ultra-precision grinding

Early studies on robot machining were reported in the 1990s. Even though there are continuous worldwide researches on robot machining ever since, the potential of robot applications in machining has yet to be realized. In this paper, the authors will first look into recent development of robot machining. Such development can be roughly categorized into researches on robot machining system development, robot machining path planning, vibration/chatter analysis including path tracking and compensation, dynamic, or stiffness modeling. These researches will obviously improve the accuracy and efficiency of robot machining and provide useful references for developing robot machining systems for tasks once thought to only be capable by CNC machines. In order to advance the technology of robot machining to the next level so that more practical and competitive systems could be developed, the authors suggest that future researches on robot machining should also focus on robot machining efficiency analysis, stiffness map-based path planning, robotic arm link optimization, planning, and scheduling for a line of machining robots.

https://link.springer.com/content/pdf/10.1007%2Fs00170-012-4433-4.pdf

Robot machining: recent development and future research issues

Innovations in Abrasive Products for Precision Grinding

https://bura.brunel.ac.uk/bitstream/2438/1352/3/Paper-Cheng.pdf

Design of ultraprecision machine tools with applications to manufacture of miniature and micro components

Development of Micro Selective Laser Melting: The State of the Art and Future Perspectives

Abrasive fine-finishing technology is often applied as a final finishing process, and the selection of the right technology is crucial to obtaining the desired performance of functions such as fatigue life. This paper begins with classifications of the technology along with fundamentals and brief histories of the individual methods. The material removal mechanisms, specific energies, and finishing characteristics of the various technologies are summarized giving assessments of the surfaces created by them. Guidelines developed for selecting the appropriate methods, and case studies illustrate the effectiveness of various methods. This paper ends with a discussion of the future prospects of the technology. (C) 2016

Abrasive fine-finishing technology

Micro abrasive pencils with CVD diamond coating

For a 6R milling robot, it is necessary to convert the postprocessing cutter locations (CL) into the robot’s revolute joint variables. This paper introduces an algorithm for calculating the forward and inverse kinematics of a 6R robot according to the CL data generated by conventional CAD/CAM systems. A redundant mechanism is analyzed to avoid the singular configurations and joint limits. The Denavit–Hartenberg (D–H) convention is referred to for developing the forward kinematics, and a closed-form solution of the inverse kinematics is presented by means of kinematic decoupling. A fundamental approach with modifying factor for avoiding singularity are developed with regard to three-axis and five-axis CL data. A gap bridging strategy is applied to reduce the jerk motion caused by tool retraction and cut paths connection. Finally, the result is conducted to simulation and machining test to verify the algorithms.

Closed-form inverse kinematics of 6R milling robot with singularity avoidance

The method involves processing a surface to be coated of a base plate (20) i.e. cylindrical hollow body, of a product with a cutting tool under formation of an undercut (21), and afterwards coating the surface of the base plate. Another undercut (22) is introduced into the surface of the base plate with another cutting tool before the coating of the product, where the undercut (22) is aligned, oriented and opposite to the undercut (21). The undercuts are produced with geometrically predefined cuttings by the cutting tools. The two cutting tools are arranged on a common tool carrier. Independent claims are also included for the following: (1) a coated product with a base plate (2) a tool for implementing a method for producing a coated product.

Coated product producing method, involves introducing undercut into surface of base plate i.e. cylindrical hollow body, with cutting tool before coating of product, where undercut is aligned, oriented and opposite to another undercut

The invention relates to a method for producing a coated product (20) with a basic body, the surface of which is worked with a cutting tool (11, 12) in a material-removing manner and with the formation of an undercut, and is subsequently coated, wherein a second undercut (22), which is aligned such that it is oriented opposite the first undercut (21), is introduced into the surface with a second, material-removing cutting tool.

Hans-Werner Hoffmeister

Papers

Abrasive fine-finishing technology

Micro abrasive pencils with CVD diamond coating

Closed-form inverse kinematics of 6R milling robot with singularity avoidance

Coated product producing method, involves introducing undercut into surface of base plate i.e. cylindrical hollow body, with cutting tool before coating of product, where undercut is aligned, oriented and opposite to another undercut

Method for producing a coated product, product and tool for carrying out the method