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Important applications of robots with continuous path control such as arc-welding, deburring, flame cutting, coating and assembling cannot successfully be implemented without sensor feed back. The paper deals with the organisation of sensorinterfaces, the conditioning and processing of the necessary sensor signals. In this context a method for on-line path control and path correction is discussed, which is able to overcome most dynamic errors of the robot systems.

Coordinate measuring machines (CMMs) frequently are used for measuring tasks at bevel gears even though probing at inclined tooth profiles causes enormous length measuring uncertainties. In order to analyse these faults on principle a master bevel gear can be used, which however is very difficult to manufacture and to calibrate in a sufficient accuracy. Therefore a task specific gauge consisting of basic geometric elements has been developed, which can be calibrated with smallest uncertainties. After the tested CMM has probed a grid of defined measuring points, the maximum quality of bevel gears to be measured can be assessed.

NC programs can be easily and safely checked by dynamic simulation. After having typed in the coordinates of the unmachined part, the contour of the workpiece, chuck and tool are displayed. Then the NC program is run step by step, and the tool is moved on the screen in real time.

Complex requirements regarding the combination of geometric functions and mechanical properties cannot be met by conventional materials. Low wear and high strength in aggressive environments, at high temperatures or high strength combined with low weight, are some characteristics of those materials. Full exploitation of the outstanding properties requires machining processes which base on the respective material features and preserve the advantages of the material as well as cost efficiency.

Monocrystalline silicon is presently the most commonly used substrate material for the production of microelectronic components (microchips) worldwide. The machining of this material is critical to high quality standards. Abrasive processes such as ID cut-off grinding, surface grinding, lapping, polishing and dicing are applied to monocrystalline silicon and will be considered in this paper. With the development of new components (i.e. the 64 Mbit chip), the electronic industry now has higher standards for the total thickness variation (TTV) and the wafer warp (less than 1 μ m on a wafer with a diameter of 200 mm). New research work on abrasive technologies is discussed. For cutting a silicon bar into waters. grinding/slicing (GS) can replace ID cut-off grinding. In the field of surface finishing the competitive technologies of doublesided lapping grinding on a rotary table and grinding with a rotating wafer are applied. A comparison of doubleside and mechanochemical polishing is made. In addition, the results of several investigations into the material removal mechanisms and surface and subsurface measurements will be dealt with in the paper.

The process performance in grinding of advanced ceramics can be enhanced by various kinematics of tool engagement. Based on the process principles of creep feed grinding with and without ultrasonic assistance, the surface formation of both methods is analyzed using analogy tests which simulate the engagement of single grains into the surface. The ultrasonic superposition leads to altered mechanisms of surface formation as well as wear behavior of grains. SEM-pictures, residual stress analyses and bending strength tests serve to evaluate surfaces ground both with and without ultrasonic assistance. This furnishes proof that ultrasonic assistance results in significantly higher removal rates, but not in an additional damage of the sub-surface.

In machine tool engineering, it is essential for purposes of thermal behaviour optimization that the design engineer takes several considerations into account. These may be classified under the headings of design and compensation. This paper outlines two design and two compensatory methods investigated. The accuracy of numerical calculations during the draft phase are to o great extent influenced by the boundary conditions applied, in particular by the heat-transfer coefficients. The Influence of convective heat transfer on the machine tool headstock has been investigated in this work. Recent trends have shown that modern engineering materials having favourable thermal properties offer a promising solution. Comparative tests on ceramic, fibre reinforced plastic and steel spindles have been undertaken in this regard. In the first method, for the compensation of displacement for existing designs, the axial displacement of the front portion of the spindle is maintained at a constant value through the use of a radiant heating system. The second method relates to the determination of displacement of machine tool components. The average temperatures of such components are recorded using resistance thermometers. These temperatures are directly proportional to the component displacements.