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The paper discusses a flexible honing technology by describing the new prototype machine with its specificity. Three original methods produced by the flexible honing prototype have been studied. A path combines the two contemporary methods of industrial honing: the helical slide honing at 135° at the bottom of the cylinder and the conventional honing at 45° on the upper part. This method of honing shows the effectiveness of specific motion tracking to remove traces of inversions. Circular trajectories with large radii can be traveled quickly without consuming too much energy. The high cutting speed promotes the removal of material thus saving time. Finally, the multi-circle paths can get original textures thus proving the feasibility of all patterns. [ABSTRACT FROM AUTHOR]

Abstract: A new process chain for near-net-shape forged and immediately heat-treated crankshafts omits soft pre-machining by a direct grinding process. Due to distortions and allowance distribution, the forged workpiece axis differs from the optimum machining axis. In-process alignment regarding eccentricity and tilt errors is required. For tilt error compensation an active tailstock is presented here. Combined hydraulic and piezoelectric actuators move the tailstock center in two degrees of freedom to produce a workpiece counter-tilt. A varying tool engagement, cooling, workpiece deflections, control deviations and machine compliance affect the contour-controlled grinding process. Here, a model based approach for process pre-control is described. [Copyright &y& Elsevier]

Abstract: Increasing automation paired with demands from high speed and high performance cutting leads to the need for process monitoring methods which avoid faulty or destructive conditions. This paper describes new monitoring methods using a sensory machine tool. By integrating a sensing fixture and an adaptive sensory milling spindle the process and workpiece behavior can be observed from both sides of the process. Interaction of these components allows new monitoring capability. A new concept for sensor fusion results in methods for automated self-calibration and a detailed insight into the process. Effects from spindle, workpiece and process dynamics can be separated. [Copyright &y& Elsevier]

Abstract: A new roll-based process and machine for three-dimensional bending of profiles with symmetrical and asymmetrical cross-sections have been developed. Compared to conventional processes like stretch bending, the advantage of the Torque Superposed Spatial (TSS) bending is the kinematic adjustment of the bending contour, leading to higher flexibility and cost efficiency, especially in small batch production. To define the spatial geometry of the workpiece, a torque is superposed to the bending moment. Results of the analytical and numerical investigations concerning the mechanics of deformation and the machine parameters of the new process are presented. [Copyright &y& Elsevier]

Abstract: Analysing the machine tool and the machining process individually is necessary in order to tackle the challenges that both have to offer. Nevertheless, to fully understand the manufacturing system, e.g. vibrations, deflections or thermal deformations, the interactions between the manufacturing process and the machine tool also have to be analysed. In cutting, grinding and forming there are important effects that can only be explained through these interaction phenomena. This paper presents the current state of research in process–machine interactions for a wide variety of manufacturing processes. It is based on the findings of the CIRP research group “Process Machine Interaction (PMI)” and on the international publications in this field. Cutting with defined and undefined cutting edges as well as sheet and bulk metal forming are the key processes. The emphasis is on understanding, modelling and simulating all modes of interaction. Additional needs of research in process–machine interaction are identified for future projects. [Copyright &y& Elsevier]

Abstract: Complete processing in one machine calls for a configuration targeting major process stability as well as a structure geared towards accuracy and dynamism. The compromise between potential dynamism and machine size can be improved by using redundant drives. The advantageous use requires the specialization on partitioning of the complete motion. With the presented algorithm the reactive sectioning of a multidimensional motion into two components with different dynamic characteristics succeeds. This provides a useful basis for the application of the principle of dynamic sectioning for a suitable design of drive redundant machine structures. This paper describes models, simulation tools and the method of the development process. [Copyright &y& Elsevier]

Abstract: In sheet metal forming damages of the free formed tool surfaces occur due to wear or foreign bodies. Fast reacting maintenance is necessary to avoid bottlenecks in workpiece supply of subsequent production steps. A transportable hybrid kinematics machining unit has been developed for repair processing of metal forming tools near the production line. This paper describes strategies to improve the positioning accuracy of the machining unit and methods for optimised surface digitising with an integrated touch probe. Calibration of the hybrid kinematics is based on an enhanced kinematics model which allows the description of geometric errors, compliance and thermal effects. [Copyright &y& Elsevier]

Abstract: This study explores a method to reduce thermally-induced errors of machine tools through temperature stabilization with compressed air. The method uses inexpensive, specially-shaped, silicon tubing with small slits. Compressed air forced through such tubing increases heat dissipation from the surface through Coanda-effect cooling. This paper describes experiments performed on a simulated heat source as well as a turning center to evaluate and improve the effectiveness of the method. The results show that this system, which can easily be applied to existing machines, can significantly reduce thermal drift and may be a viable alternative to other methods to reduce thermally-induced errors. [Copyright &y& Elsevier]

Abstract: One important demand on spindle systems in modern machine tools is to realise higher rotational speeds in order to increase the machining efficiency. Additionally, for a given speed range a better robustness is demanded so that the spindle system is desensitised against improper operating conditions. The paper presents research results in various fields which contribute to the improvement of spindle-bearing systems. At first, new results for alternative spindle bearing kinematics with four contact points are presented. Secondly, a new solution for floating bearing arrangements is discussed. A modified cylindrical roller bearing is presented which can be operated at higher speeds. Finally, the potential of coated bearing components is discussed in the context of improved fail-safe properties. In this paper both analytic studies and experimental tests are presented. [Copyright &y& Elsevier]

Abstract: A newly designed adaptronic component with a powerful piezo-stack actuator for active damping of machine vibrations is presented in this paper. Especially for machine tools with parallel kinematics, which feature lightweight structures and which are built in order to obtain high processing speeds, the active damping of machine vibrations is important to achieve the desired system performance. Extensive simulation studies with flexible multibody systems in order to test different control algorithms such as dissipative control, integrated force feedback or H2/H∞ control and recent experimental results show the high potential to improve the system behavior. [Copyright &y& Elsevier]