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During the finishing of contact surfaces of rotary shaft lip type seals, unwanted lead patterns may appear. Depending on the direction of rotation, these spiral marks may lead to early leakage or dry run, which may affect directly the longevity of the parts. New methods for satisfying the high requirements of the automotive industry are presented to determine the lead angle, the period length, and the number of starts. In contrast to earlier approaches, with a new fusion strategy, a robust extraction of the parameters of interest is attained even in the case of slightly pronounced lead structures. Moreover, by enhancing the measurement set-up with additional optical components, an in-line inspection becomes possible.

The positioning and production accuracy of handling devices is affected by various influences dependent on the handling device and the handling process. The continously changing load distribution of the handling device and the handled object according to the handling task both result in deviation from the directed motion. The motion of point-to-point-controlled handling devices must be executed time-optimal and without overshooting. Path-controlled handling devices should have a limited path error regardless of the travelling speed.

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 substitution of many lapping processes by face grinding on lapping machines offers a new field of application for the kinematic model of relative motions in lapping. The selection of path types and velocities between parts and grinding wheels does not, as in lapping, primarily serve to avoid the profile wear of the wheels. Rather, the process development and thus, the part quality are directly influenced. Ceramic parts are used as an example to illustrate the improvement in performance made possible by the analysis of machining kinematics.

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.