ANALYSIS AND IMPLEMENTATION OF
PRODUCT MANUFACTURING INFORMATION AT TAMK
Sven Weper
BACHELOR’S THESIS May 2019
Mechanical Engineering Allgemeiner Maschinenbau Double Degree
ABSTRACT
Tampereen ammattikorkeakoulu
Tampere University of Applied Sciences Degree Programme in Mechanical Engineering
Hochschule Hannover – University of Applied Sciences and Arts Fakultät Ⅱ – Maschinenbau und Bioverfahrenstechnik
Studiengang Allgemeiner Maschinenbau (MAB-AM)
WEPER, SVEN:
Analysis and Implementation of Product Manufacturing Information at TAMK Bachelor's Thesis 82 pages, appendices 9 pages
May 2019
The purpose of this Bachelor's Thesis was to identify requirements for the use of Prod- uct Manufacturing Information (PMI) for Coordinate Measuring Machine (CMM) in- spections at Tampere University of Applied Sciences (TAMK) and analyze benefits and risks. Research work classified PMI in context of Model-Based Definition (MBD) and outlined the current state and significance of this technology.
A practical implementation test in this thesis included the generation of PMI data in Siemens PLM NX 11 CAD and subsequent reuse for inspection using Mitutoyo MiCAT Planner 1.6 software and Crysta-Apex S 574 CMM. This process indicated, that the use of PMI data can increasingly automate CMM programming, but software compatibility is currently a restrictive factor. MiCAT Planner does not support PMI in neutral file formats, which causes dependency on certain CAD systems and can limit data ex- change. MBD and the use of PMI data is currently not widely used but will yield more importance in different engineering processes.
Das Ziel dieser Bachelorarbeit war die Ermittlung von Anforderungen für die Nutzung von Produkt Manufacturing Information (PMI) für Messungen mit Koordinatenmess- maschinen (KMM) und Analyse von Vorteilen und Risiken. Innerhalb von Recherche- arbeit wurde PMI in den Zusammenhang mit Model-Based Definition (MBD) einge- ordnet und der gegenwärtige Stand und Bedeutung dieser Technologie dargestellt.
Ein praktischer Test zur Umsetzung im Rahmen dieser Bachelorarbeit beinhaltete die Erzeugung von PMI Daten mit dem CAD Programm Siemens PLM NX 11 und die Wiederverwendung für KMM Messungen unter Verwendung von Mitutoyo MiCAT Planner 1.6 Software und Crysta-Apex S 574 KMM. Dieser Vorgang zeigte, dass die Nutzung von PMI zur zunehmenden Automatisierung bei der Erstellung von KMM Programmen beiträgt, aber Software-Kompatibilität gegenwärtig ein begrenzender Fak- tor ist. MiCAT Planner unterstützt PMI nicht in neutralen Dateiformaten, was zur Ab- hängigkeit bestimmter CAD Programme führt und den Dateiaustausch einschränkt.
MBD und die Nutzung von PMI Daten ist gegenwärtig nicht sehr verbreitet, aber die Bedeutung wird zukünftig in verschiedenen Prozessen des Ingenieurwesens zunehmen.
Key words: Product Manufacturing Information (PMI); Coordinate Measuring Machine (CMM); Model-Based Definition (MBD); Mitutoyo MiCAT Planner
CONTENTS
Ⅰ LIST OF FIGURES ... V
Ⅱ LIST OF TABLES ...VII
Ⅲ ABBREVIATIONS AND TERMS ... VIII
1 INTRODUCTION ... 1
2 THEORY AND CLASSIFICATION OF MBD AND PMI ... 2
2.1 Technical communication ... 2
2.2 Model-Based Enterprise (MBE) ... 4
2.3 Model-Based Definition (MBD) ... 6
2.4 Product Manufacturing Information (PMI) ... 7
2.4.1 Graphical PMI ... 9
2.4.2 Semantic PMI ... 10
2.5 Different levels of technical communication and product definition ... 10
2.6 Ranking of MBD and PMI in selected product lifecycle phases ... 12
2.6.1 Product development and construction ... 13
2.6.2 Product manufacturing ... 15
2.6.3 Quality inspection ... 16
3 STATE OF SCIENCE AND TECHNOLOGY ... 17
3.1 Background on MBD technology ... 17
3.2 Current utilization of MBD in industry ... 18
3.3 Technical literature and standards ... 19
3.4 MBD and PMI in current CAD systems and CMM applications ... 21
3.5 Initial situation at TAMK ... 22
3.5.1 Coordinate Measuring Machine: Mitutoyo Crysta-Apex S 574 ... 23
3.5.2 Mitutoyo MiCAT Planner ... 25
4 METHOD AND THESIS OBJECTIVE ... 27
5 IMPLEMENTATION OF PMI ... 29
5.1 Test workpiece development and construction ... 29
5.1.1 Requirements for test workpiece ... 29
5.1.2 CAD modelling of test workpieces ... 31
5.1.3 Change of CAD model to closed solid model ... 33
5.2 Adding PMI annotations to the solid workpiece model ... 34
5.2.1 Definition of workpiece datums ... 35
5.2.2 Definition of geometric workpiece tolerances ... 36
5.2.3 Adding of workpiece dimensional PMI ... 38
5.2.4 PMI in 3D-CAD model view ... 39
5.3 Save 3D-CAD model including PMI ... 39
5.4 Import of workpiece 3D-CAD model containing PMI ... 40
5.4.1 Dimensional Measuring Equipment (DME) selection ... 44
5.4.2 Design model placement ... 44
5.5 Generation of CMM program ... 45
5.6 CMM inspection of test workpiece ... 47
6 RESULTS ... 48
6.1 Requirements for PMI implementation ... 48
6.1.1 CAD software... 48
6.1.2 Supported CAD models ... 49
6.1.3 Supported PMI annotations ... 50
6.1.4 Supported file formats ... 52
6.1.5 CMM software environment ... 53
6.2 Benefits of PMI implementation ... 54
6.2.1 CMM programs ... 54
6.2.2 Increase of productivity... 54
6.2.3 Reducing errors ... 56
6.3 Risks of PMI implementation ... 56
6.3.1 Dependence on CAD systems ... 56
6.3.2 CAD models ... 57
6.3.3 Compatibility between CAD software and CMM software ... 58
7 CONCLUSION AND OUTLOOK ... 59
REFERENCES ... 62
DECLARATION OF AUTHORSHIP ... 64
APPENDICES ... 65
Appendix 1. 2D drawing of correct test workpiece ... 65
Appendix 2. 2D drawing of defective test workpiece ... 66
Appendix 3. Translation results of imported test workpiece STEP AP242 file ... 67
Appendix 4. Translation results of imported test workpiece part file ... 69
Appendix 5. Measurement Report of correct test workpiece ... 72
Appendix 6. Measurement Report of defective test workpiece ... 73
Ⅰ LIST OF FIGURES
FIGURE 2-1: Simplified product lifecycle and some involved stakeholders ... 3
FIGURE 2-2: Classification of MBD and PMI ... 5
FIGURE 2-3: Example of an MBD dataset ... 6
FIGURE 2-4: Examples of GD&T and non-geometric PMI ... 8
FIGURE 2-5: Difference between graphical PMI and semantic PMI ... 9
FIGURE 2-6: Different levels of technical communication and product definition ... 11
FIGURE 2-7: Ranking of MBD / PMI in product development-manufacturing- inspection chain ... 12
FIGURE 2-8: Comparison of MBD (a) and model centric (b) concept in product development and construction phase ... 14
FIGURE 3-1: CMM software environment at TAMK ... 23
FIGURE 3-2: User interface of MiCAT Planner 1.6 ... 26
FIGURE 4-1: Concept for PMI implementation ... 28
FIGURE 5-1: Basic workpiece geometry modelled in Siemens PLM NX 11 ... 31
FIGURE 5-2: Final CAD model and model history of test workpiece ... 32
FIGURE 5-3: Supported CAD formats ... 33
FIGURE 5-4: Procedure for the creation of a closed solid body in Siemens PLM NX 11 ... 33
FIGURE 5-5: Solid body in model history of Siemens PLM NX 11 ... 34
FIGURE 5-6: Activating of PMI application in Siemens PLM NX 11 ... 34
FIGURE 5-7: User Interface of PMI Application in Siemens PLM NX 11 ... 35
FIGURE 5-8: Definition of test workpiece position tolerance (PMI-No. (4)) in Siemens PLM NX 11 ... 36
FIGURE 5-9: Definition of linear dimension PMI-No. (10) in Siemens PLM NX 11 ... 38
FIGURE 5-10: Overview of PMI-No. (1)-(12) added to the workpiece CAD model ... 39
FIGURE 5-11: Generation of a STEP AP242 file in Siemens PLM NX 11 ... 40
FIGURE 5-12: Home tab with five basic MiCAT Planner operations ... 41
FIGURE 5-13: Imported part file in 3D View and associated PMI in Characteristic Reporting View ... 41 FIGURE 5-14: Comparison of PMI data generated in Siemens PLM NX 11 and
reused in Mitutoyo MiCAT Planner 1.6 ... 42 FIGURE 5-15: Workpiece placement on CMM table and collision avoidance
zone ... 44 FIGURE 5-16: Extract from generated CMM program with explanations ... 46 FIGURE 5-17: Extract from part program after translating to GEOPAK with
explanations ... 47 FIGURE 6-1: Error message of imported design model referring to table 6-1 a) ... 50 FIGURE 6-2: CMM programming time savings... 55
Ⅱ LIST OF TABLES
TABLE 2-1: Selected PMI examples referring to figure 2-4 ... 8
TABLE 3-1: ASME standards in context with MBD ... 20
TABLE 3-2: ISO standards in context with MBD... 20
TABLE 3-3: MBD / PMI applications in common CAD software ... 21
TABLE 3-4: PMI applications in common CMMs ... 21
TABLE 3-5: Technical data of CAS574 ... 24
TABLE 5-1: List of requirements for test workpiece development ... 30
TABLE 5-2: Defined test workpiece datums ... 35
TABLE 5-3: Definition of test workpiece tolerances ... 37
TABLE 5-4: Definition of test workpiece dimensions ... 38
TABLE 5-5: Summary of imported design models ... 40
TABLE 5-6: Comparison of PMI data generated in Siemens PLM NX 11 and reused in Mitutoyo MiCAT Planner 1.6 after importing design model ... 43
TABLE 6-1: Comparison of supported / not supported CAD models in MiCAT Planner ... 49
TABLE 6-2: PMI reference objects for hole features ... 51
TABLE 6-3: Interpretability of dimensional PMI for MiCAT Planner ... 51
TABLE 6-4: Supported Siemens PLM NX 11 file formats for MiCAT Planner import... 52
Ⅲ ABBREVIATIONS AND TERMS
.prt Part file in CAD software applications
.stp STEP file
.x_t Parasolid Model Part File
2D Two-dimensional
3D Three-dimensional
AB Aktiebolag (Swedish name for a limited company) AG Aktiengesellschaft (public limited company)
AL Level of automation
AP Application Protocol
ASME American Society of Mechanical Engineers
CAD Computer-Aided Design
CAE Computer-Aided Engineering
CAM Computer-Aided Manufacturing
CAS574 Crysta-Apex S 574
CAx Computer-Aided X (X - technologies)
CMM Coordinate Measuring Machine
CNC Computer Numerical Control
DME Dimensional Measuring Equipment
DMIS Dimensional Measuring Interface Standard
e.g. For example (exempli gratia)
EWL Effective Working Length
FEA Finite Element Analysis
FT&A Functional Tolerancing and Annotation GD&T Geometric Dimensioning and Tolerancing
GPS Geometrical Product Specifications
HsH Hochschule Hannover – University of Applied Sciences and Arts
Inc. Incorporated
ISO International Organization for Standardization
Max. Maximum
MB Megabyte
MBD Model-Based Definition
MBE Model-Based Enterprise
MCOSMOS Mitutoyo Controlled Open Systems for Modular Operation Support
METSTA Mechanical Engineering and Metals Industry Standardiza- tion in Finland
MiCAT Mitutoyo Intelligent Computer Aided Technology
MPE Maximum Permissible Error
N.d. No date
No. Number
PDM Product Data Management
PLC Product Life Cycle
PLM Product Lifecycle Management
PMI Product Manufacturing Information
QA Quality Assurance
SFS Finnish Standards Association (Suomen Standardisoimisliit- to SFS ry)
STEP Standard for the Exchange of Product Model Data
TAMK Tampereen ammattikorkeakoulu (Tampere University of Applied Sciences)
TDP Technical Data Package
TPD Technical Product Documentation
US United States
VDI Verein Deutscher Ingenieure (The Association of German Engineers)
1 INTRODUCTION
Product information have been exchanged through two-dimensional technical drawings between different actors in a product lifecycle for decades. This reliable method of transferring technical product information is still the predominant way of technical communication in many engineering processes, although the product modelling is done in 3D using CAD systems. Why do not completely share product information with 3D- CAD models and expand their functionality in order to replace 2D drawings?
CAD, as an already approved standard in product development processes nowadays, offers the possibility to append all information included in an engineering drawing and additional technical data directly to the 3D-CAD model. Replacing 2D drawings through annotated 3D-CAD models cause fundamental changes in technical communi- cation and revolutionize the exchange of technical information through datasets within a product lifecycle. Communicating product information through digital annotated 3D- CAD models and enable the use of this data in engineering workflows is called Model- Based Definition (MBD). A dedicated group of those annotations are Product Manufac- turing Information (PMI). Once PMI were added to the CAD model, this data can be reused in downstream engineering processes like manufacturing or inspection, which is the main benefit of PMI within MBD workflows.
Tampere University of Applied Sciences (TAMK) is involved in research projects about MBD and is initially going to integrate the use of PMI for CMM inspection.
The aim of this Bachelor´s Thesis is to analyse and implement the use of PMI at TAMK. Background and classification of MBD and PMI, extended with research about the state of science and technology form the first part of this thesis.
A practical implementation process, beginning from the CAD modelling of a developed test object using Siemens PLM NX 11, to the final CMM inspection based on PMI us- ing Mitutoyo MiCAT Planner 1.6 is included in the second part of this thesis.
This process investigated, how reuse of PMI data in CMM inspection as a selected downstream engineering process is possible with available hardware and software with- in TAMK’s mechanical engineering laboratories. Requirements, as well as benefits and risks were identified and form the basis for the handling of PMI related work packages for CMM inspection in the future.
2 THEORY AND CLASSIFICATION OF MBD AND PMI
2.1 Technical communication
Technical communication is the way to exchange technical information between differ- ent stakeholders within the whole product lifecycle. In this process, engineering knowledge in accordance with a product circulates to guarantee a safe, effective and efficient use of a product (tcworld GmbH, n.d.).
Figure 2-1 shows a general technical product lifecycle starting from an innovation, which is an introduction of a new product or device. After the product runs through dif- ferent development phases, beginning from the conceptual design to the final product construction, manufacturing processes are initiated. Manufactured products must pass the final quality inspection, before they are delivered to the customer. Depending on the product, a manual installation or final assembly by the customer might be necessary.
Subsequently, the product is ready for operation and is usually used until the lifespan is exceeded or the product gets broken and proper functionality is not possible anymore.
During the product operation, repair and maintenance work might be necessary. Finally, the product is disposed or can be recycled. New technologies, changes and improve- ments of the previous product are some reasons for continuous development and inno- vations. A modified or new innovative product sets the initial point for the product lifecycle to start again.
The general product lifecycle in figure 2-1 shows the significance of distinct technical communication through technical drawings within the product lifecycle. This lifecycle in figure 2-1 is a simplified illustration without details or referring to a specified product and its main purpose is to outline technical communication in the context of digital product definition based on MBD for this thesis work.
From the first conceptual design of an innovation, derived from a simple paper-based sketch of an idea, engineering drawings are mandatory for all further steps in order to guarantee accurate technical communication between different actors involved in the product lifecycle. Engineering drawings must transfer product definition in a clear, ex- plicit, understandable and concise way among different stakeholders throughout the product lifecycle (Quintana et al. 2010, 501). Product information must be traceable and comprehensible for a product designer, construction engineer, production scheduler, external suppliers, sales engineer and quality engineer. In addition, the customer, certi- fication authorities and other stakeholders are also involved in technical communication based on technical drawings.
FIGURE 2-1: Simplified product lifecycle and some involved stakeholders (inspired from tcworld GmbH, n.d.)
This extensive exchange of information on a product and networking between different stakeholders throughout a product lifecycle, as well as the ability to manage the entire lifecycle is called product lifecycle management (PLM).
Technical drawings are predicated on international standards (e.g. series ISO 128 Tech- nical drawings - General principles of presentation) and its fundamental purpose is to carry, control and maintain a products definition in a precise and clear way with no risk of misinterpretation or assumption (Quintana et al. 2010, 497). They have become the main instrument for managing product information, define product characteristics and confirm their actual compliance (Ricci et al. 2014, 36). Visual abstractions, standardised symbols and clearly defined methods are used to communicate complex technical as- semblies and parts in a comprehensible manner.
The communication is most effective, when different stakeholders within the product lifecycle can understand and use their relevant information provided by an engineering drawing or latterly by a 3D-CAD model with annotations.
Product designers
Construction engineers
Quality engineers Suppliers Production scheduler Calculation engineers
Sales engineers
Certification authorities
… Customers
PLC-Stakeholders exchange product information through technical communication
2.2 Model-Based Enterprise (MBE)
The term “Model-Based Enterprise” is related to the whole product lifecycle (figure 2- 1) and a 3D-CAD model as part of a Technical Data Package1 (TDP) includes all neces- sary product information for the entire cycle and involved stakeholders. It is a generic term for a business initiative, where a 3D-CAD model with additional information re- places various sets of engineering drawings and is utilized in as many product lifecycle processes as possible. It is not only a companywide strategy, as this 3D-CAD model is used within the entire supply chain and different downstream users and suppliers re- ceive product information for their purpose from that TDP, which is a common database for all operators. The term MBE also describes the development of hardware and com- puter graphics, which makes the view and utilisation of 3D models containing digital annotations and information throughout the product lifecycle possible (Cicconi et al.
2016, 526).
Figure 2-2 shows the general classification and delimitation of the MBE term in a clear manner. Arrows arranged in a circle around the MBE term emblematise, that this term always refers to the entire product lifecycle and the 3D model in a TDP is the basis for technical communication and the source for product information for all workflows.
MBD can be derived from MBE and always refers to the actual 3D-CAD modelling.
Furthermore, Product Manufacturing Information (PMI) are part of MBD and the rela- tion and differentiation between those terms is shown in figure 2-2. The amount of product information and actors in MBD is less than included in the MBE term.
This Bachelor’s Thesis will focus on MBD and especially the use of PMI. As figure 2-2 shows, both terms are derived from MBE and can always be reduced to MBE.
MBE is more related to an economic strategic orientation within an entire product lifecycle and will not be examined in this thesis work. The definition of MBE is used for the classification of MBD and PMI only, which are the main subjects of this thesis.
1 A TDP includes a technical description of an item and contains data for supporting an acquisition, pro- duction, engineering and logistics support (e.g. Engineering Data for Provisioning, Training and Tech- nical Manuals). The description defines the required design configuration or performance requirements, and procedures required to ensure adequacy of item performance. It consists of applicable technical data such as models, drawings, associated lists, specifications, standards, performance requirements, quality assurance provisions, software documentations, and packing details. (MIL-STD-31000A. 2013, 8-9 sec- tion 3.1.37.)
FIGURE 2-2: Classification of MBD and PMI2(inspired from Laaksonen et al. 2016, 6)
Note: The terms “PMI” and “MBD” are widely used by CAD software development companies in order to designate a feature for adding annotations directly to the 3D mod- el within a CAD software package. In this case, a clear differentiation and classification as shown in figure 2-2 is not discernible. PMI and MBD are referred to the same soft- ware feature and depending on the CAD vendor, PMI and/or MBD is used in manuals and CAD user interfaces.
2 Tolerances describe permissible deviations of an engineered object from the ideal design. Dimensional Tolerances address the acceptable range of minimum and maximum values of a nominal dimension. Ge- ometric Tolerances are divided in form, location, orientation and run-out tolerances and specify a geomet- ric region in which a realized feature must lie in order to meet the design criteria. (Boy et al. 2014, 3.)
3D-CAD model Projection
views
Analysis
Related documents
Exploded views
Sectional views
MBD MBE
Surface fin- ish symbols
Datum features
Geometric di- mensioning and toleranc- ing2 (GD&T)
PMI
Graphical PMI
Semantic PMI
Weld symbols Process
notes
2.3 Model-Based Definition (MBD)
The term “Model-Based definition” is referred to Computer-aided x (CAx) technologies and represents in all a method for transferring engineering information. A 3D-CAD model is the master file that holds all product information and fully defines the product (Bijnens et al. 2018, 314). It contains all necessary data to specify a product, which can be used in downstream processes and MBD is used in conjunction with the implementa- tion of digital manufacturing technologies. In differentiation to MBE, a 3D-CAD model included in an MBD dataset only incorporates product information, which makes prod- uct manufacturing, component assembly or inspection possible.
“An MBD dataset contains the exact solid, its associated 3D geometry and 3D Product Manufacturing Information (PMI) of the product’s dimensions and tolerances (and may include parts/notes lists) to specify a complete product definition.” (Quintana et al.
2010, 498).
According to figure 2-2, this information can be the solid 3D-CAD model including Product Manufacturing Information (PMI) like dimensions and tolerances, analyses as well as exploded and sectional views and attached external documents. Supplemental geometry elements, such as center lines or datum targets are no real features on the model, but communicate design requirements and are included in an MBD dataset as well. The solid 3D model can be manipulated in CAD systems and the dataset can be exported to CAE and CAM software in order to optimize the product definition and define machine-readable instructions. Unified rules and standardizations in technical communication are applied to express geometric dimensions and tolerances, which are added to a unique 3D-CAD model and included in an MBD dataset.
FIGURE 2-3: Example of an MBD dataset (Quintana et al. 2010, 499 Fig. 1.)
All data elements associated to a 3D-CAD model are enough for product definition and there is no need for 2D drawings anymore. Therefore, the MBD term is often referred to a digital product definition strategy, which describes the transition from 2D drawings to 3D-CAD models, but is no synonymous expression for paperless engineering. Those drawingless 3D-CAD models contain the same amount of information as displayed in 2D drawings and are the source for geometry and detailed product definition. In most engineering processes, the product to be manufactured is defined through the coexist- ence of a 3D-CAD model and a 2D drawing derived from that model. Instead of having two separate files, the 2D drawing and the solid 3D-CAD-model fuse into an MBD da- taset (figure 2-3). This MBD dataset contains the same information from the 2D draw- ing with additional information, by adding all dimensions and annotations to the 3D- CAD model, which can be used in downstream engineering processes.
MBD is an advanced way of antecedent product definition methods and a change within technical communication, which nowadays is a trend to appear in different manufactur- ing industries. This change to 3D-CAD models through MBD also affects the product development process and is expanded from constructive design to the manufacturing process and the final quality inspection (section 2.6).
2.4 Product Manufacturing Information (PMI)
Product Manufacturing Information (PMI) are referred to 3D-CAD systems and the term is imbedded in MBD as shown in figure 2-2. The term “PMI” includes annotations to specify Geometric Dimensioning and Tolerancing (GD&T) and non-geometric data associated with a CAD model as part of the MBD dataset (Lipman et al. 2015, 15).
All those 3D annotations are commonly referred as PMI data by commercial CAD liter- ature and its primary purpose is to represent the product’s physical and functional re- quirements (Quintana et al. 2010, 498).
PMI as part of the MBD term includes those kinds of annotations, which are used to define a product geometry and its specifications in accordance with standards. All re- quirements for a proper part manufacturing and inspection, like GD&T are conveyed through PMI and embedded into a 3D-CAD model. The 3D model acts as a legitimate and sanctioned method for the complete documentation of PMI (Siemens PLM Soft- ware Inc. 2011, 1). In addition, this PMI data generated in CAD software conveys prod- uct definition information and supports the reuse in analysing, manufacturing and in- spection processes. Attributes like GD&T, datum features, surface properties (e.g.
roughness), weld symbols, material specifications, finish requirements and process
notes are PMI. PMI derived from MBD term, only refers to those annotations and are displayed with symbols for technical communication mostly known from technical drawings standards. Some examples of PMI data are shown in figure 2-4 and explained in table 2-1.
FIGURE 2-4: Examples of GD&T and non-geometric PMI
TABLE 2-1: Selected PMI examples referring to figure 2-4
Symbol: Explanation: Type of PMI
data:
Referring standard:
80 ± 0.1 Linear dimension GD&T data ISO 129-1:2018
⊕
∅ 0.1 A B C Position tolerance(Location tolerance) GD&T data
ISO 1101:2017
⏊ 0.2 A B
Perpendicularity tolerance (Orientation tolerance)
GD&T data
▱
0.1 Flatness tolerance(Form tolerance) GD&T data Fillet weld Non-geometric
data ISO 2553:2013 Surface roughness Non-geometric
data ISO 1302:2002 PAINT THIS SURFACE
PER ISO 12944 Process note Non-geometric
data -
The product information contained in the MBD term include PMI, which are only linked to GD&T and specific non-geometric data to enable interrogation in downstream engineering processes like manufacturing and inspection. The term MBD is used in the entirety of digital product development and ensures a complete 2D drawingless product definition. MBD includes more content from technical drawings and views with addi- tional information to define a product and comprises CAD elements from the solid 3D model.
There are two subdivisions of PMI: Graphical PMI and semantic PMI (figure 2-5). De- pending on the purpose, both kinds of PMI are relevant within engineering processes and are explained in separate subsections.
FIGURE 2-5: Difference between graphical PMI and semantic PMI (Ramesh 2017, 8)
2.4.1 Graphical PMI
Graphical PMI are for presentation purposes and are also known as “PMI presentation”
in literature. The graphical mapping of PMI annotations and its location at a 3D-CAD model are specified by connecting lines and arcs. Those connecting elements visualize the association between a PMI annotation and a part of the 3D-CAD model geometry (Andre et al. 2002, 2). Following those connecting elements, which appearance differ in terms of shape, colour and positioning, makes it comprehensible for the viewer to un- derstand, where the annotation exactly refers to, which reduces the risk of interpretation errors. Figure 2-5 shows an example of GD&T referring to a through-bore hole speci- fied by a blue connecting line.
Graphical PMI meet engineering viewing purposes and visualization of PMI within the use of MBD. Single annotations as shown in figure 2-5 can be displayed only and they
are not directly associated with a cylinder object (through-bore hole) within the 3D- CAD model. Different viewers and actors of the product lifecycle can use PMI directly added to a 3D-CAD model instead of getting them out of 2D drawings. In this case, graphical PMI comply the same technical communication purpose as in 2D drawings but displayed in a 3D format. They are not consumable by any downstream manufactur- ing or inspection software and can be used for non-automated manufacturing and in- spection processes by retrieving PMI manually from the annotated 3D-CAD model.
2.4.2 Semantic PMI
Semantic PMI are machine readable and for representation purposes. They are also known as “PMI representation” in literature.
Semantic PMI are character based and complement graphical PMI. Information about the type, value and reference are stored within semantic PMI and are readable for soft- ware packages. Semantic PMI contain numerical values and it is determined to which references theses values refer to (Bijnens et al. 2018, 315). There is no presentation pur- pose and semantic PMI enable the utilization of computer-interpretable applications in downstream engineering processes. Semantic PMI, which have been added to a 3D- CAD model, can be reused in machining and inspection PLC phases, which is a funda- mental benefit and contributes to more automation.
The selected position tolerance PMI of the through-bore hole in figure 2-5 shows, that references are assigned within the entire workpiece when using semantic PMI. This selected PMI is associated to a cylinder feature (through-bore hole) and is provided in a machine-readable data format. It makes the reuse of CAD data for different stakeholders in downstream engineering applications possible and GD&T included in semantic PMI can be transferred from CAD to CAM and CMM software. Semantic PMI embedded in CAD data is processed in CMM software and supports the automatic generation of measurement programs.
2.5 Different levels of technical communication and product definition
According to Dassault Systèmes, Laaksonen et al. and Ramesh there are four different maturity levels when moving from a drawing-based workflow to an MBE environment.
The different levels are visualized in figure 2-6 and briefly described in the following.
FIGURE 2-6: Different levels of technical communication and product definition (in- spired from Dassault Systèmes 2014, Laaksonen et al. 2016 and Ramesh 2017)
In the first drawing centric maturity level, a 2D drawing is the master and the central source for technical communication within design and manufacturing processes. This 2D drawing is the main product definition method and not linked to any 3D-CAD mod- el.
In a model centric workflow, which characterizes the second maturity level, a 3D model is designed in CAD software and a derived 2D drawing used for manufacturing and inspection. A verified 3D model is used, but a 2D drawing remains the authority for product definition. Model centric workflows are currently the most common ways and integrated methods to define a product.
Moving towards the third maturity level to an MBD workflow means, that the 3D model becomes the master for technical communication in all designing and manufacturing processes. A generated MBD dataset including PMI data can be used for downstream engineering processes like manufacturing or CMM inspection. Moving from a model centric to an MBD workflow requires changes in technical communication from a 2D
(1) DRAWING CENTRIC 2D Drawing is the master and used for de-
sign and manufacturing
Mat uri ty L ev el ( 1) – (4 )
(2) MODEL CENTRIC 2D drawing is the master,3D models are used for design and derived 2D drawings are used for manufacturing
(3) MBD
3D Model is the master and used for design and manufacturing
(4) MBE
A fully loaded 3D Model is the master and used for design and manufacturing and
within all business processes
Product development
Product release
Product development
and construction
Product manufacturing Quality inspection
Manual gauging / CMM inspection.
Generation of a 3D- CAD model represent-
ing the final product design and including
all PMI data.
Manual manufac- turing or auto- mated manufac-
turing using CAM software.
reuse of PMI data
drawing to an annotated 3D-CAD model and changes in equipment acquisition in terms of software and hardware are necessary.
The fourth maturity level describes an MBE approach, which means that a fully loaded 3D model in a TDP is used by different users within a product lifecycle. As this term is linked to a business strategy with more complex processes and networks between dif- ferent actors, it is not taken into consideration for this thesis.
Especially the second and third maturity level, which are highlighted in orange and ac- centuated by bold lines in figure 2-6, show the transition from a model centric towards MBD workflow and are relevant levels for this thesis work.
2.6 Ranking of MBD and PMI in selected product lifecycle phases
The ranking of MBD and PMI is based on the general product lifecycle in figure 2-1 on page 3. MBD and PMI, its generation in any CAD software and downstream consump- tion are relevant in selected phases at the beginning of a product lifecycle and shown in detail in figure 2-7. Main processes in the phases are highlighted in figure 2-7 and ex- plained in separate subsections.
FIGURE 2-7: Ranking of MBD / PMI in product development-manufacturing- inspection chain
2.6.1 Product development and construction
Basis for the beginning of the product development and construction phase could be an innovation, modification of an existing product or a customer request for the construc- tion of a device. A list of requirements for the final product, which a contractor has agreed on with a client has usually to be done before.
The product development and construction phase can be split into product development phase and product release phase (Quintana et al. 2010, 500). Within the product devel- opment phase, the conceptual design based on a sketch is developed and more details are added. Besides, the requirement list is considered and listed functional needs should be realized within the construction. The final design is the result of this phase and the initial point for the production release phase. It is a continuous increase of the product definition level and finally all relevant information are included in the construction, so that downstream engineering processes can begin.
Figure 2-8 shows the role of MBD in this phase of the product lifecycle. It also illus- trates the difference between MBD and a model centric workflow, which describes the coexistence of a solid CAD model and a drawing derived from that model.
In this context, there is still a need for a paper-based sketch when MBD is the used method and the initial point remains unchanged for defining a product. A sketch is a mean of technical communication in order to illustrate concepts based on the general product arrangement. Further elaboration of the design within product development phase is based on a solid 3D-CAD model without 2D drawings when using MBD.
The level of changes of the constructive design is high at the beginning of the product development phase and decreases when the final design is reached. More and more de- tails and parts are added to the construction, to confirm the product intent. Before the final design is reached, stress and strength calculations based on solid MBD model are done to analyse the product performance. The obtained analysing results might lead to further changes within the construction. All changes are directly visible on the 3D-CAD model, which is the basis for technical communication and the number of annotations and PMI added to the model increase continuously within this phase.
Changes in design when using a solid model and a drawing (model centric workflow) must usually be done on the 3D-CAD model at first. After that, the 2D drawing must be updated in order to display the actual product and guarantee accurate technical commu- nication.
FIGURE 2-8: Comparison of MBD (a) and model centric (b) concept in product devel- opment and construction phase (Quintana et al. 2010, 500 Fig. 2.)
In the product development and construction phase, the final MBD model is a 3D digital prototype and ready for manufacturing (Zhu et al. 2016, 487). Its primary purpose is the creation of digital product datasets of the final design including PMI, which can be used in subsequent product manufacturing and quality inspection phases. The responsibility and workload of a product designer in an MBD workflow increases compared to a mod- el centric workflow. Reuse of PMI data in subsequent PLC phases must already be con- sidered and ensured in product development and construction phase.
In order to enable interoperability and use of PMI data generated in this phase in follow- ing software applications for manufacturing and inspection, a suitable data format is required. As involved stakeholders might use different CAD software, the conversion is an important procedure to make an exchange of PMI data and the reuse within down- stream applications possible. Neutral file formats (e.g. STEP), which are based on inter- national standards or CAD software related data formats (e.g. part file) and supported in downstream applications, must equally represent PMI data, as generated during product development and construction phase.
2.6.2 Product manufacturing
Dedicated content of the MBD dataset including PMI, which was generated in the pre- vious product development and construction phase, can be reused in the subsequent product manufacturing phase.
For the manufacturing of workpieces using manual machining methods, MBD including all necessary PMI serves as an alternative to 2D drawings. Machine operators or me- chanics working on the shop floor level can get all necessary dimensional and tolerance information for manufacturing from an annotated 3D model including PMI. Such tasks like manual milling, lathing or drilling can be performed using GD&T information from graphical PMI, which are displayed on a screen or tablet. Graphical PMI distribute the product definition as part of technical communication between the product development and construction department and machine operators. They can retrieve graphical PMI to control manual manufacturing and are the source for proper machine setting adjustment.
PMI data can be used for the automation of CNC programming tasks, which are usually done prior to the real manufacturing process. CAM software uses the 3D-CAD model with PMI provided in a dedicated file format to define and validate machine-readable instructions for manufacturing (Lipman et al. 2015, 15). Semantic PMI can facilitate CNC programming tasks by generating optimized toolpaths as features and forms of an imported CAD model and information about tolerance and surface quality are readable for CAM software. CAM software often adopt the nominal dimension from the 3D- CAD model to create the toolpath. In order to consider tolerances for toolpath pro- gramming, manual adjustment is necessary by extracting tolerance data from 2D draw- ings.
GD&T in semantic PMI are interpretable by proper CAM software and machine opera- tors do not manually have to adjust the tolerances to the middle tolerance value any- more, which reduces the risk of errors significantly.
Tools can be selected automatically and the parameter adjustment (e.g. speed, feed) is done based on a 3D model including semantic PMI. In this context, the term Model- Based Manufacturing (MBM) is used and PMI in this phase increase the level of auto- mation3 and technical stuff on the shop floor is increasingly responsible for correct ex- amination and supervision of the program functionality.
3 The level of automation is the relation between automated functions to the overall (manual + automated) functions of a production system in terms of costs or stages of production: 𝐴𝐿 = 𝑎𝑢𝑡𝑜𝑚𝑎𝑡𝑒𝑑
𝑚𝑎𝑛𝑢𝑎𝑙+𝑎𝑢𝑡𝑜𝑚𝑎𝑡𝑒𝑑 (1).
2.6.3 Quality inspection
The utilization of manual gauging and CMM for the final control of a products quality is important during quality inspection phase and relevant in the context of MBD. Manu- al gauging as a measuring method for a products quality evaluation can use graphical PMI to display a products GD&T set values. Requirements expressed in GD&T and other properties of the final product design, engineered in the product development and construction phase and their compliance after product manufacturing must usually be checked, before delivering the product to the customer.
Graphical PMI connected to a 3D-CAD model are the source to receive information about the ideal geometric shape of a product and can be used instead of 2D drawings.
Measuring points can be shown by graphical PMI and a set-actual comparison between the manufactured product dimensions and the ideal 3D model including PMI can be performed.
Software packages from different metrological companies can read GD&T included in semantic PMI, which have been attached to a 3D-CAD model and were provided in a dedicated file format during product development and construction phase. CMM soft- ware can use machine-readable PMI and the associated CAD model geometry to gener- ate a measuring program for the check of GD&T and constraints such as perpendiculari- ty or circularity of manufactured parts. Semantic PMI act as the central distributor for products ideal GD&T properties, which are the source for measuring program genera- tion and comparison with the real parts geometry. Based on predefined tolerances in- cluded in semantic PMI, a manufactured part is evaluated, if it meets the tolerances or not (Mitutoyo Corporation 2018, 10).
In this phase, semantic PMI enable an automatic creation of measuring programs for CMMs and this increases the level of automation. Less time is spent on manual pro- gramming by CMM technicians and extraction of GD&T from 2D drawings as a manu- al input for CMM software is replaced by directly reading PMI from an imported file.
The software identifies features from the CAD geometry and PMI and prepares an ap- propriate tool for inspection and previews the CMM probe inspection path in a simula- tion environment. After CMM program execution and quality inspection of a product, the delivered measurements are documented in a report.
3 STATE OF SCIENCE AND TECHNOLOGY
3.1 Background on MBD technology
3D modelling in CAD became possible in the 1980s and the product definition was primary represented through 2D drawings. First ideas to add GD&T and all annotations directly to 3D models as an alternative to 2D drawings came up around the turn of the millennium. The term MBD and its extensive technology as described in section 2.3 and shown in figure 2-2 did not exist during that time. It was initially an initiative to change technical communication by using annotated 3D models without reuse of certain data for further engineering processes. Continuous development and enhancement of product definition based on 3D models was driven by CAD software development companies.
The Boeing4 company was one of the initiators of the MBD technology (Zhu et al.
2016, 486). Sharing Boeing’s expertise and supported by the American Society of Me- chanical Engineers (ASME), research on MBD began in 1997 and a first MBD standard (ASME Y14.41 2003 – Digital product definition data practices) was published in 2003.
This standard formed the basis for MBD and was latest updated in 2012. It is still im- portant for 3D part definition practices using MBD in the US until today.
MBD applications were integrated in prevalent CAD software. For example, the French company Dassault Systèmes, which developed the CAD program SolidWorks, pub- lished a first 3D drawing application “eDrawings” in 1999. A first MBD dimensioning software tool (DimXpert) included in SolidWorks was introduced in 2008 and complet- ed by the release of SolidWorks MBD software package in 2015 (Dassault Systèmes 2014, 2). Other CAD software vendors, like Siemens PLM released an MBD applica- tion in their CAD program NX about the same time.
Besides the implementation of the MBD technology in different CAD programs, down- stream engineering CAE and CAM software was advanced to make PMI data utilisable.
CMM manufacturer like Mitutoyo released software in 2014, in order to use semantic PMI data for the generation of automatic part measurement programs, which reduces time and effort to create CMM programs.
4 Boeing is a US based aerospace company and the largest manufacturer of civil and military aircrafts worldwide.
3.2 Current utilization of MBD in industry
The progress of MBD implementation in industry is on a different level, dependent on the branch of industry. Applying MBD workflows is more common in the US. Especial- ly in aerospace, automotive and defence industries it is widely-used and those industries are currently the main drivers of the MBD trend (Quintana et al. 2010, 506). For exam- ple, the Boeing company adopted MBD for designing parts of the Boeing 777 aircraft.
Suppliers and external industrial partners were involved in a complete digital product definition process in an MBE environment. Adopting MBD was required for Boeings subcontractors, if they were considered as suppliers.
In other industries, MBD is currently less utilized and slowly becomes more popular.
According to figure 2-6, the model centric concept (second maturity level) is still the predominant workflow in most industries and all the single data including the 3D-CAD model and the corresponding 2D drawings are often managed in a PDM/PLM system.
Some industries are thinking of adopting MBD into operating procedures or are current- ly in a transition period of MBD implementation. Companies need to decide, if restruc- turing from a model centric workflow to an MBD workflow is worthwhile and realiza- ble. There are currently only few single companies which utilized MBD besides aero- space and automotive.
Furthermore, there are industries, where some actors within a product lifecycle already start to use MBD, but this technology is not completely adopted in the whole product lifecycle yet. An example is the Finnish automotive supplier Valmet Automotive Inc.5, which shares MBD data with Daimler AG (Simons, J. 2019). A rapid spread and indus- try-wide trend of MBD utilization is in many cases retarded through concerns about a complete renunciation of 2D drawings (Ruemler et al. 2017, 6). 2D drawings are gener- ally seen as a safe and proven way of transferring technical product definition. Imple- mentation of MBD in an industrial company means changing the way of technical communication, when getting rid of 2D drawings and downstream engineering process- es are affected. It is a barrier which needs to be overcome and a general view on the diverse manufacturing industrial sector exempt from aerospace and automotive de- scribes, that MBD is not widely utilized yet, but the MBD concept accepted in industry (Ruemler et al. 2017, 2).
5 Valmet Automotive Inc. is an upstream provider for the automotive industry based in Uusikaupunki, Finland. The company was founded in 1968 and provides engineering and manufacturing services for automobile industry. Customers are amongst others BMW, Daimler and Porsche.
There is currently no company in Finland, which implemented complete MBD work- flows or uses PMI data in an appropriate CMM software for measuring program genera- tion. The technology and use of PMI data slowly becomes popular and will be more relevant in the future. (Vainio. 2019.) In general, the use and technology of PMI for machining and inspection purposes in industry is still evolving and further improve- ments are expected.
CAD software development companies included MBD and PMI in various software packages and hold it in readiness. This group exposes MBD as an advanced technology in a digital engineering environment and mentions the benefits of MBD. In order to convince more companies towards MBD implementation, prevalent arguments are the reduction of product development costs and delays due to inaccurate engineering draw- ings (Quintana et al. 2010, 498).
The utilization of MBD and its influence on industry is currently discussed in science and between different actors in industry. Several engineering associations like ASME are publishing journal articles to introduce the MBD concept and outline its benefits and risks based on industrial examples. This association is currently very active in the dis- cussion of MBD and has developed standards (e.g. ASME Y14.41 – 2012: Digital Product Definition Data Practices) for 3D model definition in cooperation with national standardization institutes since the beginning of MBD technology.
National standardization institutes like METSTA in Finland are publishing reports in cooperation with companies, universities and CAD software reseller, in order to give advice and a guideline on MBD for Finnish industries. METSTA acts as an official and reliable source for Finnish companies, which are thinking of adapting MBD and informs about the opportunities of MBD workflows.
3.3 Technical literature and standards
There are different well-established international standards for technical communication through technical drawings and requirements for technical product documentation.
Some already implemented standards for technical communication are valid in conjunc- tion with MBD as well. The US standard ASME Y14.41 and international standard ISO 16792 are currently the standards for MBD technology and provide specifications about digital product definition.
A brief overview about selected ASME and ISO standards concerning MBD is given in tables 3-1 and 3-2.
TABLE 3-1: ASME standards in context with MBD
ASME Y14.41:2012 Digital Product Definition Data Practices
This US standard provides regulations for the display, orientation and query of annota- tions added to a 3D model.
ASME Y14.5:2009 Dimensioning and Tolerancing TABLE 3-2: ISO standards in context with MBD ISO 16792:2015
SFS-ISO 16792:2015
Technical product documentation – Digital product definition data practices
This international standard includes MBD aspects and was mostly adapted from ASME Y14.41:2012. It has the status of a Finnish national standard and is the basic source for MBD and indicates requirements for annotations applied to a 3D model.
There are several normative references with basic rules to communicate the product definition on 2D drawings, which are indispensable for this standard. Some selected relevant standards referring to ISO 16792 are listed below:
- ISO 128 (all parts): Technical drawings – General principals of presentation - ISO 129-1:2018: Technical product documentation (TPD) – Presentation of di-
mensions and tolerances – Part 1: General principles
- ISO 1101:2017: Geometrical product specifications (GPS) – Geometrical toler- ancing – Tolerances of form, orientation, location and run-out
- ISO 2553:2013: Welding and allied processes – Symbolic representation on drawings – Welded joints
- ISO 5459:2011: Geometrical product specifications (GPS) – Geometrical toler- ancing – Datums and datum systems
- ISO 14405-1:2016: Geometrical product specifications (GPS) – Dimensional tolerancing – Part 1: Linear sizes
- ISO 14405-2:2018: Geometrical product specifications (GPS) – Dimensional tolerancing – Part 2: Dimensions other than linear or angular sizes
ISO 10303-242:2014
Industrial automation systems and integration - Product data representation and exchange - Part 242: Application protocol:
Managed model-based 3D engineering
This standard is about the neutral file format STEP application protocol (AP) 242, which was approved by ISO in 2014. It deals with the exchange of data from an origi- nating CAD application in a neutral data format, that retains an annotated 3D-CAD model with PMI and makes it readable for CAE, CAM systems and other downstream software applications.
This STEP AP242 combines the scopes of STEP AP203 (ISO 10303-203:2011) and AP214 (ISO 10303-214:2010), which are for specified engineering domains (Lipman et al. 2015, 16). Moreover, it means that (Boy et al. 2018, 1):
- Graphical PMI are supported by STEP AP203e2, AP214e3 and AP242.
- Semantic PMI are only supported by STEP AP242.
3.4 MBD and PMI in current CAD systems and CMM applications
The MBD technology including the generation of PMI is currently available in common CAD software packages. Updated software releases procure improved MBD applica- tions and the functionality level is going to rise. The amount of applications within MBD varies slightly between CAD software packages and the designation of the MBD application is depending on the software. A brief overview on current MBD / PMI ap- plications integrated in common CAD software is given in table 3-3.
TABLE 3-3: MBD / PMI applications in common CAD software
CAD software: MBD application: Availability at TAMK:
YES NO
Autodesk Inventor
Professional 2018 Annotate x
Dassault Systèmes Catia v6 FT&A Workbench x
Dassault Systèmes SolidWorks 2018
DimXpert
SOLIDWORKS MBD x
PTC Creo Parametric 5.0 Annotation Feature x
Siemens PLM NX 11 PMI Application x
Siemens PLM Solid Edge ST 10 PMI Application x
Different CMM manufacturer developed software, which can import CAD models with semantic PMI in a dedicated file format to generate CMM measurement plans and pro- grams. A brief overview on current CMM software packages using PMI are compiled in table 3-4.
TABLE 3-4: PMI applications in common CMMs CMM manufacturer: CMM software for pro-
cessing PMI:
Availability at TAMK:
YES NO
Hexagon Metrology PC-DMIS CMM x
Mitutoyo MiCAT Planner Acquisition in 2019
Zeiss Metrology Calypso x
3.5 Initial situation at TAMK
TAMK is currently adopting new future-orientated technologies within mechanical en- gineering laboratories (F0-19). MBD as a digital product definition technology and es- pecially the use of PMI data in downstream engineering applications should be imple- mented at TAMK and an analysis combined with a practical test for that process is per- formed by this thesis work. Besides, some local companies are interested in ongoing research projects about the use and implementation of PMI at TAMK.
Siemens PLM NX 11, Autodesk Inventor Professional 2018 and Dassault Systèmes SolidWorks 2018 CAD software with MBD and PMI applications are currently availa- ble (table 3-3), but PMI data has not been generated and used for any downstream engi- neering processes at TAMK before.
The handling of the MBD applications within installed CAD systems and the generation of PMI data is currently unknown. It is unidentified, what are the requirements and how reuse of PMI data generated by available CAD software is possible in engineering pro- cesses at TAMK, such as FEA or CMM inspection.
According to the different maturity levels of technical communication and product defi- nition in figure 2-6, the initial situation at TAMK is ranked to the second maturity level, which describes a model centric workflow. This initial situation correlates with the cur- rent situation in Finnish industry, but changes and increasing significance of MBD workflows including the use of PMI data are expected.
TAMKs mechanical engineering laboratory is equipped with a Mitutoyo CMM type Crysta-Apex S 574, which currently uses Mitutoyo MCOSMOS6-3 v.4.1.R1 measure- ment software for the inspection and dimensional analysis of parts. This CMM software does not support PMI and the CMM measuring program generation based on PMI is currently not possible. TAMK is going to purchase Mitutoyo MiCAT Planner software in order to implement the use of PMI data for CMM inspection procedures in 2019.
The general ranking and significance of MiCAT Planner within TAMKs CMM software environment is shown in figure 3-1.
6 MCOSMOS [Mitutoyo Controlled Open Systems for Modular Operation Support] is a modular CMM software system developed by MiCAT [Mitutoyo Intelligent Computer Aided Technology] for measuring and evaluating procedures within coordinate measuring technology. The software is currently available in three different levels (MCOSMOS 1/2/3), which differ in terms of included packages and can be expand- ed by optional modules.
Green coloured elements indicate available software and yellow elements show soft- ware, which is going to be purchased. An enhancement of the software environment with MiCAT Planner enables import of 3D-CAD models with PMI data from Siemens PLM NX 11 for the CMM program generation and execution in MCOSMOS module GEOPAK7.
FIGURE 3-1: CMM software environment at TAMK
The available CMM type and the proposed software to be purchased, are briefly de- scribed in the following subsections referring to figure 3-1.
3.5.1 Coordinate Measuring Machine: Mitutoyo Crysta-Apex S 574
Mitutoyo Crysta-Apex S 574 (CAS574) is a bridge type CMM according to ISO 10360- 1:2000. The bridge is constructed by a horizontal beam with two posts and is movable in Y-direction. The horizontal beam enables X-direction movement and contains the probe head with holding fixture for different sensor types for the Z-direction movement.
Linear movement with less friction is enabled by air bearings on each axis and move- ment is CNC-controlled. A controller determines the position (encoder) and current Cartesian coordinates of all three axes and transmits X-, Y- and Z-values for evaluation in the MCOSMOS software. The machine consists of a granite measuring table and a base plate with threaded inserts fixes parts during inspection. The right side of the gran- ite table serves as guide surface for the bridge Y-direction movement.
7 GEOPAK is a standard geometry module available in all MCOSMOS software packages.
Product development
and construction Quality inspection
3D-CAD model with
PMI data Siemens PLM NX 11
MiCAT Planner v1.6
MCOSMOS-3 v.4.1.R1 GEOPAK Module
CMMs are usually equipped with scanning or tactile switching probes. The latter probe with synthetic ruby ball tip and changeable probe head angle is used for CMM inspec- tion in context with this thesis. Discrete coordinate values are recorded when the stylus tip touches different points on a part and are assigned to defined features like planes or circles within the software. The X-, Y- and Z-coordinates of those points are recorded, when the stylus tip touches the part surface and activates the tactile switching. Meas- urement points form a scatter-plot and regression algorithms in MCOSMOS software process the transmitted coordinate data. Based on this input data, e.g. distances or posi- tions of features are calculated and geometrical forms (e.g. cylindricity, circularity) are evaluated.
According to ISO 10360-2:2009, the guaranteed accuracy expressed by the maximum permissible error for length measurements of this CMM is:
𝐸0,𝑀𝑃𝐸= (1.7 + 3 ∙ 𝐿
1000) 𝜇𝑚 [𝐿 = 𝑚𝑒𝑎𝑠𝑢𝑟𝑖𝑛𝑔 𝑙𝑒𝑛𝑔𝑡ℎ 𝑖𝑛 𝑚𝑚] (2)
The maximum permissible probing error using SP25M probe with ∅ 4 mm x 50 mm stylus according to ISO 10360-5:2010 is 𝑃𝐹𝑇𝑈,𝑀𝑃𝐸 = 1.7 𝜇𝑚.
Technical data of CAS574 CMM is summarised in table 3-5.
TABLE 3-5: Technical data of CAS574 (Mitutoyo America Corporation 2015, 3) Measuring
range
X-axis: 500 mm
Y-axis: 700 mm
Z-axis: 400 mm
Resolution: 0.0001 mm
Max. drive speed: 519 mm/s Max. acceleration: 2.309 mm/s2 Measuring
table
Material: Granite Size: 638 mm x 1160 mm Workpiece Max. height: 545 mm
Max. mass: 180 kg
Mass: 625 kg
Z X
All measuring programs are currently generated manually using Mitutoyo MCOSMOS software. A control panel with joysticks can be used in CMM learn mode for manual movement and teaching of points to generate a CMM program. Program modifications are performed in part program editor and the final program for a certain part to be in- spected is executed using CMM repeat mode.
3.5.2 Mitutoyo MiCAT Planner
Mitutoyo MiCAT Planner is a software package for Mitutoyo CMMs to generate meas- uring programs based on CAD models with or without PMI data. A 3D-CAD model with semantic PMI of a part to be inspected can be imported in MiCAT and then used to automate the generation of CNC CMM inspection plans.
MiCAT Planner works with MCOSMOS and is the necessary software within the entire software environment in figure 3-1, which is needed to reuse CAD models with PMI from product development and construction phase in quality inspection phase.
A CAD model is composed of features like planes, cylinders or circles, which are read- able for MiCAT Planner (Mitutoyo Corporation 2018, 136). GD&T information in- cluded in PMI are converted to inspection characteristics. Supported characteristics are different geometric tolerances and dimensional tolerances (e.g. distance or diameter dimensions). If a CAD model without PMI data is imported or PMI is incomplete, GD&T can be manually added.
User-defined measurement rules, defaults and user parameter settings are determined in MiCAT Planner. All those settings performed in MiCAT, as well as a selected DME configuration created with system manager in MCOSMOS, are inputs to generate a measurement program. An automated CMM measurement program is the output from MiCAT Planner and guided to Mitutoyo MCOSMOS software module GEOPAK (fig- ure 3-1). Finally, GEOPAK is the software module, which executes the part program on the CMM and generates the measurement report.
MiCAT Planner 1.6 is the latest version released by Mitutoyo in May 2018 and used for this thesis work. Continuous updates improve and expand the functionality of this soft- ware in the future. The general user interface of MiCAT Planner 1.6 with the main ele- ments and views is shown in figure 3-2.
FIGURE 3-2: User interface of MiCAT Planner 1.6
The user interface is basically divided in five main display blocks, which are framed in figure 3-2. Different tabs for view changes can be selected below the display blocks on the left side of the user interface.
The Home Tab consist of six dialog boxes, which guide the user stepwise from the im- port of the CAD model with PMI to the final measurement program translation into GEOPAK module. An imported design model and a selected DME configuration are displayed in the 3D View in the centre of the user interface. Manipulation of views, set- tings and displaying measurement paths/points are controlled by the 3D View Toolbar.
All PMI of an imported design model are listed in a tree structure in the Plan View on the left side of the user interface. The order of characteristics and sort sequence for the measurement report is defined in Characteristic Reporting View tab. Information about the DME configuration, added DME collision avoidance zones and CMM tools (sensor types) are displayed in the DME View. Settings for different features with associated characteristics, datums and measuring point sets from the Plan View are adjusted in the Properties View below. Changes of GD&T for characteristics and datums derived from PMI of the imported design model are performed in GD&T View tab. A generated measurement program is chronologically displayed in the Program View on the right side of the user interface. It enables simulation of the generated program running on the virtual DME inspecting the imported design model in 3D View.
Properties View / GD&T View Home Tab
3D View with 3D View Toolbar
Program View Plan View / Characteristic Reporting View / DME View
