Tool path generation for ultra-precision machining of free-form surfaces

Brinksmeier, E.; Riemer, Oltmann; Osmer, J.

doi:10.1007/s11740-008-0086-4

Cited by 30 publications

(13 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Free-form surfaces are industrially milled by machines with five or more axes [8-10]. Such milling processes can only be carried out on ceramic components in a green- or white-body state.…”

Section: Methodsmentioning

confidence: 99%

Manufacturing conditioned roughness and wear of biomedical oxide ceramics for all-ceramic knee implants

Turger

Köhler

Denkena

et al. 2013

BioMedical Engineering OnLine

View full text Add to dashboard Cite

BackgroundCeramic materials are used in a growing proportion of hip joint prostheses due to their wear resistance and biocompatibility properties. However, ceramics have not been applied successfully in total knee joint endoprostheses to date. One reason for this is that with strict surface quality requirements, there are significant challenges with regard to machining. High-toughness bioceramics can only be machined by grinding and polishing processes. The aim of this study was to develop an automated process chain for the manufacturing of an all-ceramic knee implant.MethodsA five-axis machining process was developed for all-ceramic implant components. These components were used in an investigation of the influence of surface conformity on wear behavior under simplified knee joint motion.ResultsThe implant components showed considerably reduced wear compared to conventional material combinations. Contact area resulting from a variety of component surface shapes, with a variety of levels of surface conformity, greatly influenced wear rate.ConclusionsIt is possible to realize an all-ceramic knee endoprosthesis device, with a precise and affordable manufacturing process. The shape accuracy of the component surfaces, as specified by the design and achieved during the manufacturing process, has a substantial influence on the wear behavior of the prosthesis. This result, if corroborated by results with a greater sample size, is likely to influence the design parameters of such devices.

show abstract

“…Free-form surfaces are industrially milled by machines with five or more axes [8-10]. Such milling processes can only be carried out on ceramic components in a green- or white-body state.…”

Section: Methodsmentioning

confidence: 99%

Manufacturing conditioned roughness and wear of biomedical oxide ceramics for all-ceramic knee implants

Turger

Köhler

Denkena

et al. 2013

BioMedical Engineering OnLine

View full text Add to dashboard Cite

show abstract

“…w i, j and w k, l are the corresponding weight factors. More in-depth knowledge for NURBS-based surface descriptions can be explained in Weck et al, 14 Piegel and Tiller 15 and Brinksmeier et al 16 It is common knowledge that the conventional machine tool system cannot demystify directly from this description of a freeform surface. Therefore, it is deemed necessary to pre-process the surface data into a tool trajectory with point clouds.…”

Section: Hybrid Fts/sss Diamond Turning and Freeform Surfacesmentioning

confidence: 99%

CAx-technologies for hybrid fast tool/slow slide servo diamond turning of freeform surface

Neo

Kumar

Rahman

2016

Proceedings of the Institution of Mechanical Engineers, Part B:

View full text Add to dashboard Cite

Most of commercial CAM software solutions (SolidCAM, Unigraphics and etc.) are commonly employed for generating tool paths on machining of freeform surfaces. However, these CAM software solutions are presently unable to support fast tool/slow slide servo diamond turning of freeform surface due to difference in coordinating systems. In contrast to traditional machining processes, fast tool/slow slide servo diamond turning is controlled by both linear and angular positions of the workpiece and is known as polar or cylindrical coordinate system. Hence, a special CAM post-processor is required to generate the spiral tool trajectory in fast tool/slow slide servo diamond turning. However, these special CAM software solutions are very expensive. Manufacturers have been searching for solutions to sustain their competitive advantage in mass producing products at the shortest time to market and at a most economical cost. Hence, these drive the needs for an alternative and economical option of generating accurate tool trajectory for fast tool/slow slide servo diamond turning of freeform surfaces. This article proposes an attractive solution with an integration of Visual Basic application programming interface into SolidWorks to generate spiral tool trajectory for diamond turning of freeform surface. In this proposed methodology, the spiral tool trajectory can be extracted directly from computer-aided design models of freeform surface without utilizing any expensive CAM software. In addition, the critical cutting parameters and tool geometrical angles were also optimized with the developed methodologies for the accurate machining of freeform surfaces in the hybrid fast tool/slow slide servo process.

show abstract

“…However, the use of this technology depends on a high degree of the operational background regarding the kinematical interrelationships and the grinding wheel-workpiece engagement. Both are required knowledge for appropriate tool path generations by CAD/CAM systems [8]. Due to the lack of the right technology for five-axis manufacturing with grinding wheels, in past five-axis belt grinding was mostly used in mould and turbine blades manufacturing as well as for finishing of large surfaces with low curvatures [9][10][11].…”

Section: How To Grind With Five-axis?mentioning

confidence: 99%

Five-Axis-Grinding With Toric Tools: A Status Review

Denkena

Turger

Behrens

et al. 2012

Journal of Manufacturing Science and Engineering

View full text Add to dashboard Cite

Free form surfaces are used in various applications, such as in the aviation industiy, in the medicine, or for tool and die making. Compressor blades as well as knee prostheses and dies have complex curved surfaces. Five-axis grinding is a possibility to machine such curved swfaces in a high shape accuracy and surface quality. The use of this technology depends on a high degree of the operational background. Furthermore, the complexity of the tool path generation requires the use of computer-aided design/computer aided manufacturing {CAD/CAM) systems. This technical review gives an overview about state of the art of five-axis grinding and presents results, which can close some scientific lacks. Models were developed to predict the surface roughness and material removal dependent on the process parameters. Additionally, the relationship between tool geometry, shape accuracy as well as contact conditions is discussed. How to Grind With Five-Axis?Workpieces become more and more complex due to improving function, optic or haptic as well as downsizing of dimensions. These workpieces are often made of materials, which are difficult to machine. For example, complex shaped knee implants out of wear-resistant biocompatible oxide ceramics or forging dies for crankshafts reinforced by ceramic inlays [1,2]. Double curved or free formed surfaces can be ground with three-or five-axis kinematic. By applying three-axis kinematic, toric grinding wheels move line by line over the surface, whereby the tool axes are always parallel to machine tool axes [3]. However, profitability and precision of the three-axis manufacturing are limited. Changing workpiece curvatures leads to varying contact conditions and decreasing shape accuracy. In contrast to three-axis kinematic, five-axis machine tools have three translational axes (X, Y, and Z) and two additional rotational axis. These axes enable a simultaneous rotation and tilling of the tool relative to the surface of the workpiece [4,5]. As a result, the grinding wheel axis can always be oriented vertically to the normal vector of the surface and the variation of the contact conditions is reduced. Moreover, due to the high kinematic flexibility of five-axis manufacturing, undercuts as well as complex free formed surfaces are machined with high precision [6], Five-axes processes enable machining within

show abstract

Tool path generation for ultra-precision machining of free-form surfaces

Cited by 30 publications

References 4 publications

Manufacturing conditioned roughness and wear of biomedical oxide ceramics for all-ceramic knee implants

Manufacturing conditioned roughness and wear of biomedical oxide ceramics for all-ceramic knee implants

CAx-technologies for hybrid fast tool/slow slide servo diamond turning of freeform surface

Five-Axis-Grinding With Toric Tools: A Status Review

Contact Info

Product

Resources

About