Machining With Redundant Kinematics

2011 ◽  
Author(s):  
Reimund Neugebauer ◽  
Welf-Guntram Drossel ◽  
Steffen Ihlenfeldt ◽  
Hendrik Rentzsch
Keyword(s):  
Machine Tool ◽  
Development Process ◽  
Resource Conservation ◽  
Process Stability ◽  
High Productivity ◽  
Simulation Tools ◽  
Process Chains ◽  
Major Process ◽  
Machine Tool Structures ◽  
Redundant Kinematics

The demand for high productivity and quality combined with the need for decreasing energy consumption will substantially affect machine tool design in the future. This development is driven by a modification of process chains which is focused on resource conservation. One important contribution for that purpose is the transition towards complete machining. This approach 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. This paper describes models, simulation tools and the method of the development process for redundant kinematics. To highlight the different aspects of designing such machine tool structures, their development process is demonstrated on the basis of two examples, complete machining for tool- and die making and an adaptive spindle holder for micro contouring and -structuring.

Efficient Simulation of Parallel Kinematic Machine Tools

2009 ◽  
Author(s):  
Martin Kipfmu¨ller ◽  
Christian Munzinger
Keyword(s):  
Machine Tool ◽  
Machine Tools ◽  
Development Process ◽  
Special Focus ◽  
Full Potential ◽  
Parallel Kinematic Machine ◽  
Machine Tool Industry ◽  
Simulation Tools ◽  
Parallel Kinematic ◽  
Parallel Kinematic Machine Tools

Today’s machine tool industry mainly consists of small and medium-sized enterprises. Thus, the simulation of new products often does not seem to be cost effective due to the small number of items produced and the high cost of simulation tools. Nevertheless, the use of simulation tools is essential in order to tap the full potential of new challenging concepts like parallel kinematic machines. This paper presents a simulation method supporting the development process of parallel kinematic machine tools from the first concept to the prototype. In order to render the method applicable for the machine tool industry, a special focus is placed on tool efficiency. A modular modeling concept will ensure that the structure of the first kinematic model of the concept phase can be enhanced during the development process and developed into more detailed models, e.g. for dimensioning calculations or to study the dynamic behavior of machine tools. Thus, the method efficiently supports the whole development process with a simulation model gradually increasing in detail according to the requirements of the machine tool designer.

Exakte posenabhängige Strukurmodelle*/Accurate virtual machine tool structures - Online-identification of the general model of a lightweight machine tool structure with pose-dependent dynamic behavior

2017 ◽  
Vol 107 (05) ◽  
pp. 323-328
Author(s):  
S. Apprich ◽  
F. Wulle ◽  
A. Prof. Pott ◽  
A. Prof. Verl
Keyword(s):  
Machine Tool ◽  
Least Squares ◽  
Dynamic Behavior ◽  
Natural Frequencies ◽  
Recursive Least Squares ◽  
Machine Model ◽  
Online Identification ◽  
Working Space ◽  
Machine Tool Structure ◽  
Machine Tool Structures

Serielle Werkzeugmaschinenstrukturen weisen ein posenabhängiges, dynamisches Verhalten auf, wobei die Eigenfrequenzen um mehrere Hertz im Arbeitsraum variieren können. Die genaue Kenntnis dieses Verhaltens gestattet eine verbesserte Regelung der Strukturen. Ein generelles parametrisches Maschinenmodell, dessen Parameter online durch einen Recursive-Least-Squares-Algorithmus an das reale Maschinenverhalten angepasst werden, stellt Informationen über dieses Maschinenverhalten bereit.   Serial machine tool structures feature a pose-dependent dynamic behavior with natural frequencies varying by serveral hertz within the working space. The accurate knowledge of this behavior allows an improved control of the structures. A general parametric machine model, whose parameters are adapted online to the actual machine tool behavior by a Recursive Least Squares algorithm, provides information about the pose-dependent dynamic behavior.

Modal Analysis of Machine Tool Structures Based on Experimental Data

1983 ◽  
Vol 105 (4) ◽  
pp. 282-287 ◽  
Author(s):  
K. F. Eman ◽  
K. J. Kim
Keyword(s):  
Transfer Function ◽  
Machine Tool ◽  
Modal Analysis ◽  
Moving Average ◽  
Parametric Representation ◽  
Modeling Procedure ◽  
Fitting Procedure ◽  
Machine Tool Structures ◽  
Computer Based ◽  
Three Degree Of Freedom

The basic problem in modal analysis of machine tool structures is the extraction of modal parameters from the measured transfer function data. Conventionally this task is performed in two steps. The transfer function is determined using a Digital Fourier Analyzer followed by a suitable curve fitting procedure. In order to avoid the inherent problems associated with these procedures a new approach for modal analysis is proposed in this paper. Anticipating the stochastic nature of the systems excitation and response Modified Autoregressive Moving Average Vector models (MARMAV) are proposed. The modeling procedure yields a parametric representation of the structural behavior allowing the extraction of the modal information in one step, directly, rather than in two as in the conventional approaches. The mathematical foundation for the approach is given along with its application to a simulated three-degree-of-freedom system and a knee type milling machine. The newly proposed procedure is commensurate to the existing ones in light of the computational efforts involved; however, it eliminates the subjective judgment of the analyst since the modeling procedure is based on rigorous statistical adequacy checks. Finally, the proposed approach is amenable for implementation in a computer-based machine tool structural dynamics analyzer.

Evaluation of Advanced Cementitious Composites for Machine-Tool Structures

CIRP Annals ◽  
1988 ◽  
Vol 37 (1) ◽  
pp. 373-376 ◽  
Author(s):  
M. Rahman ◽  
M.A. Mansur ◽  
K.H. Chua
Keyword(s):  
Machine Tool ◽  
Cementitious Composites ◽  
Machine Tool Structures
Sign in / Sign up

Export Citation Format

Share Document