1、BSI Standards Publication Machine tools Numerical compensation of geometric errors PD ISO/TR 16907:2015National foreword This Published Document is the UK implementation of ISO/TR 16907:2015. The UK participation in its preparation was entrusted by Technical Committee MTE/1, Machine tools, to Subcom
2、mittee MTE/1/2, Machine tools - Accuracy. A list of organizations represented on this committee can be obtained on request to its secretary. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standar
3、ds Institution 2015. Published by BSI Standards Limited 2015 ISBN 978 0 580 79000 3 ICS 25.080.01 Compliance with a British Standard cannot confer immunity from legal obligations. This Published Document was published under the authority of the Standards Policy and Strategy Committee on 31 March 201
4、5. Amendments/corrigenda issued since publication Date Text affected PUBLISHED DOCUMENT PD ISO/TR 16907:2015 ISO 2015 Machine tools Numerical compensation of geometric errors Machines-outils Compensation numrique des erreurs gomtriques TECHNICAL REPORT ISO/TR 16907 Reference number ISO/TR 16907:2015
5、(E) First edition 2015-04-01 ISO/TR 16907:2015(E)ii ISO 2015 All rights reserved COPYRIGHT PROTECTED DOCUMENT ISO 2015 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including
6、 photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester. ISO copyright office Case postale 56 CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22
7、749 09 47 E-mail copyrightiso.org Web www.iso.org Published in Switzerland PD ISO/TR 16907:2015 ISO/TR 16907:2015(E)Foreword v Introduction vi 1 Scope . 1 2 Normative references 1 3 T erms and definitions . 1 4 P ot ential benefits and limits of numerical c ompensation 4 5 Kinematic representation o
8、f machine tool structure 5 5.1 Machine tool configuration and designation 5 5.2 Kinematic representation of the machine tool 6 6 Geometric errors of the machine tool 6 6.1 Sources of geometric errors 6 6.2 Geometric errors of axes of linear motion 7 6.3 Geometric errors of axes of rotation 7 6.4 Pos
9、ition and orientation errors between axes of motion 8 6.5 Other relationship between axis of motion and axis average lines 10 7 Determination of geometric errors .10 7.1 General 10 7.2 Consideration on determination of geometric errors 11 7.3 Selection of the machine tool coordinate system .11 7.4 S
10、uperposition of individual errors .11 7.4.1 Rigid body behaviour 11 7.4.2 Non-rigid body behaviour .12 7.5 Direct measurement of geometric errors .14 7.6 Indirect measurement of geometric errors .15 8 Compensation of geometric errors 15 8.1 General 15 8.2 Types of geometrical compensation15 8.2.1 Ge
11、neral.15 8.2.2 Compensation for positioning errors of linear axes along specific lines, L-POS15 8.2.3 Compensation for straightness errors of linear axes along specific lines, L-STR16 8.2.4 Compensation for squareness error between axes of linear motion at specific lines, L-SQU 16 8.2.5 Compensation
12、 for the angular error motions of linear axes on 3-D position of functional point in the working volume, L-ANG 16 8.2.6 Physical compensation for errors in functional orientation, FOR 16 8.2.7 Volumetric compensation of linear axes, L-VOL 17 8.2.8 Volumetric compensation of linear axes including fun
13、ctional orientation, L-VOL+ .17 8.2.9 Compensation for positioning errors of rotary axes, R-POS .17 8.2.10 Compensation for radial and axial error motion of rotary axes, R-RAX17 8.2.11 Compensation for position and orientation errors of rotary axes, R-POR 17 8.2.12 Compensation for the tilt error mo
14、tions of rotary axes on 3-D position of functional point in the working volume, R-ANG 18 8.2.13 Volumetric compensation for rotary axis errors, R-VOL 18 8.2.14 Volumetric compensation for rotary axis errors including functional orientation, ISO 2015 All rights reserved iii Contents Page PD ISO/TR 16
15、907:2015 ISO/TR 16907:2015(E)R-VOL+ .18 8.2.15 Machine tool-specific geometry compensation for linear axes, L-SPEC .18 8.2.16 Machine tool-specific geometry compensation for rotary axes, R-SPEC 18 8.3 Role of temperature .18 8.4 Role of repeatability 19 8.5 Role of machine tool least increment step
16、.19 8.6 Role of workpiece mass and tool mass19 9 Representation of geometric errors for compensation 19 9.1 General 19 9.2 Representation in look-up tables for individual errors 20 9.2.1 General.20 9.2.2 Common error tables or compensation tables .20 9.2.3 Compensation of reversal errors 20 9.2.4 Di
17、scussions and suggestions 21 9.3 Representation as a spatial error grid .21 9.3.1 General.21 9.3.2 Common spatial error grid tables and spatial compensation grid tables .22 10 Application of numerical compensation for geometric errors .25 10.1 General 25 10.2 Alignment of the compensated motion to t
18、he machine tool structure25 10.3 Direct measurements for the generation of error tables or compensation tables 25 10.4 Indirect measurements for the generation of error tables or spatial error grids 26 10.5 Compensation of already compensated machine tools.26 11 Validation of numerical compensation
19、of geometric errors26 11.1 Measurement uncertainty and compensation 26 11.2 Considerations on operation of compensated machine tools .27 11.3 Consideration for testing compensated machine tools .27 11.4 Traceability of compensation 28 12 Documentation on compensation .28 Annex A (informative) Alphab
20、etic list of abbreviations of compensation types .29 Bibliography .30 iv ISO 2015 All rights reserved PD ISO/TR 16907:2015 ISO/TR 16907:2015(E) Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of pr
21、eparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, i
22、n liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. The procedures used to develop this document and those intended for its further maintenance are described in the ISO/I
23、EC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives). Attention is drawn to the possibility
24、 that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of paten
25、t declarations received (see www.iso.org/patents). Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement. For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as infor
26、mation about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT), see the following URL: Foreword Supplementary information. The committee responsible for this document is ISO/TC 39, Machine tools, Subcommittee SC 2, Test conditions for metal cutting machine tools. ISO 2015
27、 All rights reserved v PD ISO/TR 16907:2015 ISO/TR 16907:2015(E) Introduction This Technical Report provides information associated with numerical compensation of geometric errors of machine tools. Numerical compensation of geometric errors has the potential to increase the accuracy of parts produce
28、d on machine tools, reduce the costs for production of machine tools and assembly, and reduce the maintenance cost during the life cycle of the machine tool by adding or replacing mechanical re-fitting. The information provided in this Technical Report might be useful to the machine tool manufacture
29、r/supplier, the user, the metrology service provider, and the metrology instrument manufacturer. Valuable general information on numerical compensation of geometric errors may be gathered in Schwenke, et al 12 .vi ISO 2015 All rights reserved PD ISO/TR 16907:2015 Machine tools Numerical compensation
30、 of geometric errors 1 Scope This Technical Report provides information for the understanding and the application of numerical compensation of geometric errors for numerically controlled machine tools including: terminology associated with numerical compensation; representation of error functions ou
31、tput from different measuring methods; identification and classification of compensation methods as currently applied by different CNCs; information for the understanding and application of different numerical compensations. This Technical Report does not provide a detailed description of geometric
32、errors measurement techniques that are specified in ISO 230 (all parts) and in machine tool specific performance evaluation standards and it is not meant to provide comprehensive theoretical and practical background on the existing technologies. This Technical Report focuses on geometric errors of m
33、achine tools operating under no-load or quasi- static conditions. Errors resulting from the application of dynamic forces as well as other errors that might affect the finished part quality (e.g. tool wear) are not considered in this Technical Report. Deformations due to changing static load by movi
34、ng axes are considered in 7.4.2. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referen
35、ced document (including any amendments) applies. ISO 230-1:2012, Test code for machine tools Part 1: Geometric accuracy of machines operating under no-load or quasi-static conditions ISO 841:2001, Industrial automation systems and integration Numerical control of machines Coordinate system and motio
36、n nomenclature 3 T erms a nd definiti ons For the purposes of this document, the terms and definitions given in ISO 841:2001, ISO 230-1:2012 and the following apply. 3.1 machine tool coordinate system machine tool reference coordinate system right-hand rectangular system with the three principal axe
37、s labelled X, Y, and Z, with rotary axes about each of these axes labelled A, B, and C, respectively SOURCE: ISO 841:2001, 4.1, modified Note 1 to entry: ISO 230-1:2012, Annex A provides useful information on machine tool coordinate system and position and orientation errors. TECHNICAL REPORT ISO/TR
38、 16907:2015(E) ISO 2015 All rights reserved 1 PD ISO/TR 16907:2015 ISO/TR 16907:2015(E) 3.2 functional point cutting tool centre point or point associated with a component on the machine tool where the cutting tool would contact the part for the purposes of material removal SOURCE: ISO 230-1:2012, 3
39、.4.2 3.3 functional orientation relative orientation between the component of the machine tool that carries the cutting tool and the component of the machine tool that carries the workpiece 3.4 motion uncompensated for geometric errors linear or angular motion of machine tool axes resulting from com
40、manded motion and the error motions caused by component imperfections, components alignment errors, and/or positioning system errors 3.5 motion compensated for geometric errors linear or angular motion of machine tool axes resulting from the commanded motion and the application of (numerical) compen
41、sation of error motions Note 1 to entry: Compensation might apply to all geometric errors or to just some geometric errors. It is recommended that the type of compensation (see.8.2) is specified. Note 2 to entry: Residual errors may still exist after motion compensated for geometric errors. See 3.19
42、. 3.6 structural loop assembly of components, which maintains the relative position between two specified objects SOURCE: ISO 230-7:, 3.1.13 Note 1 to entry: A typical pair of specified objects (for a milling machine) is a cutting tool and a workpiece, in which case the structural loop would include
43、 the spindle, bearings and spindle housing, the machine head stock, the machine slideways and machine frame, and the fixtures for holding the tool and workpiece. For large machines, the foundation can also be part of the structural loop Note 2 to entry: When geometric error measurements are being pe
44、rformed, the structural loop also includes the measuring instrument components, including the reference artefacts (if any). 3.7 volumetric error model geometric model that describes the errors of the machine tool functional point and functional orientation within the machine tool working volume caus
45、ed by individual error motions as well as position and orientation errors of machine tool axes, including axis positions and other structural loop variables like tool length and tool offset Note 1 to entry: Volumetric error model may be a kinematic error model or a spatial error grid. Note 2 to entr
46、y: Other models describing the errors due to machine tool thermal effects and structural stiffness as well as dynamic models can be combined with the volumetric error model. 3.8 volumetric compensation of functional point only numerical compensation for the errors in the position of the functional p
47、oint within the machine tool working volume based on the volumetric error model, not including the compensation for the errors in the functional orientation Note 1 to entry: Errors in the functional orientation are compensated at the functional point. For cutting tools with spherical tips, the “volu
48、metric compensation of the functional point only” represents a full compensation, as orientation errors of a spherical tip do not affect the geometry of machined workpieces.2 ISO 2015 All rights reserved PD ISO/TR 16907:2015 ISO/TR 16907:2015(E) 3.9 volumetric compensation of functional point and of
49、 functional orientation numerical compensation for the errors in the position of the functional point and the functional orientation within the machine tool working volume based on the volumetric error model 3.10 kinematic error model mathematical model that describes the structural loop of a machine tool as a kinematic chain and describes the errors that are included/considered Note 1 to entry: The complexity of the kinematic error model and the number of parameters may vary. 3.11 rigid body kinematic error mo
