Creaform Ebook Series A GUIDE TO PORTABLE 3D SOLUTIONS FOR QUALITY CONTROL AND INSPECTION

Transcription

1 Creaform Ebook Series A GUIDE TO PORTABLE 3D SOLUTIONS FOR QUALITY CONTROL AND INSPECTION

2 Portable 3D scanning and optical CMM bring quality control and inspection into the mainstream Portability, reliability and simplicity: The three attributes that have historically brought new engineering and manufacturing technologies into the mainstream are working their magic on the quality control and inspection market. What used to be the province of technicians in lab coats working in hermetically sealed rooms well away from the shop floor is now undergoing an historic democratization. Portable 3D laser scanners and optical coordinate measurement machines (CMMs) now enable even novice operators to capture QC and inspection data for practically anything, anywhere.

3 The new generation of portable 3D scanning and optical CMM systems offer five major breakthroughs that are making them the go-to solutions for manufacturers and suppliers worldwide: 1. What is dynamic referencing? Dynamic referencing makes the scanner or CMM system impervious to involuntary movement, relocation of the part being scanned, and environmental disturbances such as vibrations on the shop floor. 2. Automatic alignment that eliminates inherent errors in any manual alignment process. 3. Intelligent measurement processes that optimize data and ensure greater accuracy. 4. Easy, onsite calibration that can be done by a novice operator in less than five minutes. 5. Wireless, low-cost and rugged optical targets that reduce set-up complexity while maintaining accuracy. These five breakthroughs deliver bottom-line business benefits, including faster measurements that speed time-to-market and the ability to ensure quality in every facet of product lifecycle management (PLM).

4 APPLICATIONS Where portable 3D scanning and optical CMM are making an impact The need for fast, reliable and portable measurement is growing rapidly in industrial development and production, impacting multiple quality control and inspection applications throughout the product lifecycle. The biggest impact is being seen in the most common type of quality control: production part inspection. Hand-held optical technologies are enabling companies to integrate quality control and inspection directly into the production process for a part or assembly, saving time and money. Beyond production part inspection, new portable 3D scanning and optical CMM technologies impact an increasingly wide variety of quality control applications across almost every type of industry. APPLICATIONS

5 FIRST-ARTICLE INSPECTION Portable solutions are eliminating the traditional bottlenecks associated with first-article inspection. Manufacturers can inspect parts right on the production floor, without the need to have them transported to a remote metrology lab. Parts from third-party suppliers or other facilities throughout the world can be thoroughly inspected before shipping, saving time and rework. IN-LINE INSPECTION The newest generation of portable systems can withstand the harshest environments and surrounding vibrations. This maximizes the efficiency of quality control processes throughout the production run. TOOL AND JIG INSPECTION AND ADJUSTMENT Dynamic and automatic alignment functionalities give manufacturers the ability to accurately adjust jigs and tools in just a few minutes, speeding up the alignment phase and eliminating human errors. APPLICATIONS

6 MOLD AND DIE INSPECTION Physical phenomena such as shrinkage and spring-back effect in stamping, casting and plastic injection processes complicate efforts to match manufactured parts to CAD geometry. Portable 3D measurement solutions make it easy to inspect the die/mold geometry and initially produced parts in order to reduce the number of costly design iterations and adjustments. Companies can now manufacture parts that perfectly match the CAD reference. APPLICATIONS

7 DYNAMIC MEASUREMENT The ability to capture interactions between different physical phenomena in real time has made portable 3D scanning and optical CMMs a vital part of quality control in applications such as car suspension or exhaust displacement analysis in the automotive industry, dummy positioning before crash tests, and highly accurate real-time guided assembly of rocket parts in the aerospace industry. Key aspects of dynamic measurement include: Deformation measurement Portable 3D systems enable engineers to measure a component s position and orientation in space, simultaneously and continuously, with a high degree of accuracy. This applies to deformations and displacements of objects of any size and any degree of complexity. Positioning and alignment 3D measurement solutions help manufacturers precisely position and align production machines right on the shop floor, increasing efficiency and eliminating expensive errors. Robot and machine calibration Performance of robot and CNC machines can be captured to create digital models that can be used to rapidly calibrate production machines and apply real-time course correction to robots. APPLICATIONS

8 DAMAGE ASSESSMENT Portable 3D scanning and optical CMM systems can be easily transported to damage sites to quickly and accurately pinpoint damaged areas, ascertain the potential ripple effect for surrounding areas, and minimize future risk. MAINTENANCE, REPAIR AND OVERHAUL (MRO) Ineffective maintenance and repair can gouge a company s profits and tax its resources. Portable 3D measurement solutions generate highly accurate inspection results in even the harshest environments and ambient temperatures, helping companies get their maintenance and repair work right the first time. APPLICATIONS

9 THE OPTIONS Technologies for QC and inspection The technologies currently available for 3D quality control and inspection have strengths and weaknesses. Despite some vendors claims of all-in-one solutions, potential buyers of QC and metrology systems should aim to meet 80% of their measurement needs while reducing the pressure on quality control personnel, limiting the need for inflexible equipment such as fixed CMMs, decreasing the time needed for training and implementation, and increasing the number of inspections that can be performed on the shop floor or in the field. Here s a look at the options available, how they work, and their advantages and limitations. APPLICATIONS OPTIONS CHOICE INDUSTRIES GLOSSARY

10 Measuring arm HOW IT WORKS Fixed-probe or touch-trigger probe heads mounted on an arm are positioned by mechanical encoders to capture discrete points on the object. Advantages Versatility: Many different tools, including 3D scanning heads, can be mounted on arms, enabling integration of scanning and probing Good accuracy within its working volume Can capture data in places not visible to a laser tracker beam or optical tracker Limitations Typically requires a qualified technician to operate Needs to be fixed on a surface and use a physical link (arm) for positioning Susceptible to vibrations, temperature and other environmental factors Lacks flexibility in where it can be used Not efficient for capturing complex surface shapes Extending measurement volume requires leapfrogging, a lengthy, cumbersome operation that reduces accuracy OPTIONS

11 Laser tracker HOW IT WORKS A stabilized laser beam aims at a prism, which reflects light back in the direction from which it came. A laser head records the distance from the prism and the two angles corresponding to the target direction. Advantages Great precision and good reliability Freedom of movement by removing the physical link between the scanner and the object being scanned Good for large-volume measurement Limitations Cost: $80,000 to $250,000 Typically requires a qualified technician to operate Sensitivity to obstacles cutting off the light beam Difficult or impossible to reach areas hidden from line of sight Extending the scanning parameters is difficult and can add uncertainty to measurements OPTIONS

12 Photogrammetry HOW IT WORKS Uses triangulation to extract measurements from a series of photos of an object or an environment. Advantages Enables large-scale inspection (1-10 meters or larger) Great accuracy (from mm/m to mm/m, depending on the size of what s being measured) Limitations Captures only low-density data (only target points are measured) Only surface points are measured with default targets; a specific accessory is needed for each type of geometric entity measured (two aligned targets for an axis, target pins for hole location, for example) Requires a level of expertise Significant time delay between acquisition and generating results OPTIONS

13 Fixed-location structured light scanner HOW IT WORKS Projects a pattern of light onto a part and processes how the pattern is distorted when light hits the object being scanned. Either an LCD projector or a scanned or diffracted laser beam projects the light pattern. One or more sensors record the projected pattern. Advantages Generates very high-quality data Excellent resolution, capturing even the smallest of features Speed: Can capture millions of points in seconds Limitations Typically requires a qualified technician to operate Requires multiple scans in most cases to cover all angles of complex parts, lengthening acquisition time Not portable Expensive to acquire, implement and maintain OPTIONS

14 Portable optical CMM HOW IT WORKS Optical CMM cameras track reflectors mounted to a hand-held device and the part being scanned to provide dynamic referencing in 3D space. Advantages Complete wireless portability for freedom of movement No rigid setup required; the part and optical tracker can be moved freely during measurement. Works well in unstable conditions (not impacted by vibrations, extreme temperatures or part movement) Limitations Difficult or impossible to reach areas hidden from line of sight Some use expensive wired or powered LED targets Requires a minimum stand-off distance between the part and optical tracker Advanced systems can use low-cost passive optical targets Part-size range of 1-3 meters (extendable to 10 meters) with any type of material Can be paired with a 3D scanner OPTIONS

15 Portable 3D scanner HOW IT WORKS Portable laser scanners project laser lines on an object and white-light devices project a light and shade pattern on the object. Both types of scanners analyze the resulting deformed projections to extract 3D scan data. Advantages Easy to transport and use Does not require fixed measuring setup during data acquisition Captures complex or free-form surfaces Can combine multiple positioning methods, providing the accuracy of positioning targets with the flexibility of object features and texture positioning Limitations Requires powder to be applied for capturing parts with extremely reflective or transparent materials Self-positioning is done on a local area, making it possible for errors to stack up as the scanning volume increases Lower resolution than high-end fixed-location scanners Can acquire data from unstable or moving objects Speed: The most advanced can capture half a million points per second and rebuild the 3D triangle mesh in real-time during scanning OPTIONS

16 CHOICE Probe, scan or both? An oft-asked question when assessing available 3D technologies for quality control and inspection is: Do I want to probe or scan? 3D optical probing and scanning each have their strengths and are extremely complementary. In general, probing is best when one needs to: Inspect a part that has a limited number of geometrical parameters Measure a part that has no complex surfaces Measure depressions (such as the interior of a cylinder) Take precise measurements of some points to obtain geometric alignment Inspect a shiny part without needing to prepare it with powder Periodically adjust or inspect an assembly or control jig Conduct a simple and repetitious inspection performed by an untrained operator Probing will also sharply reduce the amount of data to be processed. CHOICE

17 CHOICE Probe, scan or both? Scanning is ideal when one needs to: Inspect a part with complex shapes Get detailed information, such as that needed for conformity mapping Perform non-contact measurement Measure a complete part or assembly Perform a best-fit alignment requiring many points FOR THOSE WHO NEED BOTH TYPES OF DATA ACQUISITION, PORTABLE OPTICAL SYSTEMS THAT SCAN AND PROBE ARE AVAILABLE. THESE SYSTEMS COMBINE THE BENEFIT OF OPTICS (SPEED, PORTABILITY, REDUCED SENSITIVITY TO THE MEASUREMENT ENVIRONMENT, AND HIGHER MEASUREMENT VOLUME) WHILE REMAINING COMPATIBLE WITH FAMILIAR AND PROVEN PROBING PROCEDURES. CHOICE

18 INDUSTRY SPOTLIGHT AUTOMOTIVE Staying ahead of the ever-changing automotive manufacturing landscape No industrial sector has likely undergone more change over the last decade than the automotive market. Engineering and manufacturing have become increasingly global, driving standardization efforts such as the Automotive Industry Action Group s Production Part and Approval Process (PPAP). An explosion of new digital components, greater customization across product lines, radically different fuel sources, and emerging markets with varying requirements and desires have created the need for a greater number of inspections and quality control measures. Portable 3D scanning and optical CMM technologies are responding to these and future challenges by providing the following capabilities: Production compliance inspection Portable measurement solutions are used commonly to bring speed and reliability to three-dimensional part verification, whether using systematic or random measurements. Automatic alignment allows users to verify some characteristics of the part in less than 45 seconds, which is compatible with most production cycles. Using technologically advanced portable optical CMMs, automotive manufacturers can fully automate part verification, saving resources that would otherwise be spent on a dedicated monitoring tool based on electronic comparators. INDUSTRIES

19 AUTOMOTIVE Tool testing and adjustment Design tools (molds, jigs, racks, presses, etc.) should be periodically inspected and adjusted as part of preventive maintenance to deliver the expected level of performance. Portable optical CMMs or a hybrid solution combining 3D scanning and an optical probe can reduce adjustment times by a factor of two or more for applications such as adjusting injection press molds, testing injection or drawing molds, or assessing the geometry of a tire mold. Dynamic alignment using reflectors previously positioned at predetermined locations ensures reliable measurement in a factory environment. Wear and deformation modeling During the testing phases of new products, it is often necessary to measure distortions encountered during normal usage, or the results of wear during phases of intensive testing. Examples include the deformation of fuel tanks during thermal cycles, the movement of exhaust pipes in operation, the deformation of engine mounting-brackets, and strain during crash tests. Portable measurement solutions make it possible to inspect an item right out of the oven, automatically aligning on reflectors previously placed on jigs. Strain measurements can be done by probing or through automatic alignment using reflectors placed on checkpoints. It is possible to dynamically measure deformations or movement by monitoring up to 5,000 points per second. INDUSTRIES

20 CASE STUDY - AUTOMOTIVE One-stop automotive measurement on the shop floor Vauxhall, Britain s oldest automotive company, uses a portable optical CMM system to measure body shop tooling, general assembly and finished vehicles. The company purchased the tool primarily for flexibility: It s previous system, a fixed arm, didn t measure large-enough volumes, especially for body shop and assembly-line measurements. Previously we d have to do three, four, maybe even five setups in a cell because of the size of the product we build, says Paul Bass, Senior Quality Engineer. [The portable optical CMM] gives us much more flexibility; we can do it in one measurement, which reduces our measurement time and gives us more accuracy. With the portable system, Vauxhall can set up data acquisition in minutes, enabling inspection during lunch or other scheduled production breaks instead of paying overtime on a weekend when the production line is down. INDUSTRIES

21 CASE STUDY - AUTOMOTIVE Inspecting a rear bus chassis on the assembly line When Nova Bus, a major North American bus manufacturer, needed to inspect a vehicle rear chassis directly on the assembly line, it combined a hand-held probe with a portable optical CMM scanner to do the job. The technologies proved to be efficient, quick, versatile and flexible, says a Nova Bus engineer. Dynamic referencing ensured that the portable measuring device was continuously locked into the part by an optical link, maintaining part alignment throughout the probing and scanning process and delivering accurate measurements despite the vibrations and environmental hazards of the assembly line. INDUSTRIES

22 INDUSTRY SPOTLIGHT AEROSPACE In the aerospace industry, quality cannot be left to chance Along with automotive, aerospace is one of the most demanding of industries for quality control and inspection. With lives on the line daily, nothing can be left to chance. Aerospace faces two of the same primary market pressures as the automotive industry: greater reliance on global partners and an influx of international competitors. The need for speed is also greater than ever for aerospace companies, as OEMs confront huge order backlogs. 3D modeling for phased-array inspection Aircraft manufacturers and air carriers are faced with the challenge of nspecting complex components -- gas turbines, engine bays, nacelles, cockpits and others -- that are part of a very intricate assembly and that can t be removed for inspection. To solve this issue, the industry usually relies upon the phased-array inspection method. Fortunately, 3D portable scanning and optical CMM technologies are transitioning quality control and inspection from a necessary hurdle into a productivity accelerator. The following applications are among those benefiting from the new era of portability, reliability and simplicity. INDUSTRIES

23 INDUSTRY SPOTLIGHT AEROSPACE In the past, the 3D model for phased-array inspection would usually be a CAD file or a theoretical model construction. The problem with this methodology is that the actual component shape varies from CAD or ideal theoretical models, which in turn affects the ultrasound scan quality and lowers the probability of detecting problem areas. The new generation of 3D portable laser scanning systems generates highly accurate 3D data of the existing part, capturing every detail in accuracy up to 40 microns. Resulting 3D models reflect every change undergone by the part during manufacturing (welded joints, out of roundness, etc.) and its operating life (such as wear or dents). Portable 3D scanning can be done in a few minutes with the part remaining within the assembly. 3D scan data are fully compatible with popular ultrasonic testing and phased-array inspection software, and can be imported to generate a highly accurate 3D model to be used as the basis for simulations. INDUSTRIES

24 AEROSPACE Hail damage assessment The impact of hail damage on the aerodynamics of an airplane is a complex factor to assess, but must be completely accurate for safety reasons. The most common way of analyzing hail damage level is through geometric measurement (length, width and depth) of each dent found on a given service airplane. Portable 3D scanning systems enable engineering teams to quickly capture large amounts of data to conduct deeper analysis of hail damage. These scanners offer key benefits such as high accuracy, repeatability, traceability, portability and ease of use. Defects can be detected and measured according to configurable criteria and data can be output in popular formats (Excel, PDF) for sharing among decision-makers. Assessing as-built conditions Simulations of the as-built condition of key components and assemblies are a critical factor for aerospace companies. These simulations and virtual assembly operations help engineers determine proper design adjustments and pre-calculations of assembly positions. The ideal system for capturing the data needed for accurate simulations is one that combines portability with pinpoint accuracy. That usually calls for a 3D data-capture system that integrates 3D scanning with an optical touch probe. A hybrid system saves time by enabling on-site inspection and ensures quality by delivering reliable, streamlined and automated alignment procedures. INDUSTRIES

25 AEROSPACE Assisted assembly for manufacturing processes In complex or critical aerospace manufacturing processes, it is essential to know the position of each part in relation to others at any time and for the duration of the assembly process. Portable optical probe technology allows simultaneous three-dimensional position measurements for dozens of reflectors and re-assesses those positions 30 times per second. From the positions of three reflectors arranged on a single part, it is possible to recover the six parameters of the part s position and the orientation of the part. With such information, engineers can determine the relative position of one or many parts in relation to a reference part. It s also possible to automatically trigger alarms if a maximum tolerance is reached. Portable probe systems can be interfaced with the control command of a robot or a robotized assembly system to accurately correct a part trajectory in real time INDUSTRIES

26 AEROSPACE Maintenance The average age of commercial airliners is about 11 years. Military aircraft average about 26 years of service (B-52 bombers have been in service for 60 years). In both cases, essential pieces of equipment have to undergo regular maintenance, the frequency of which increases with age and level of service. Aircraft need to be precisely measured to determine repairs to correct warping or loss of material due to wear. After that, repairs must be checked for compliance. A fully portable device, such as one combining precise optical probing with accurate 3D laser scanning, has emerged as the ideal tool for this critical task. Portability and dynamic referencing allow for simple, reliable operations anywhere, even in restrictive conditions such as on an airport landing strip. By using a 3D scanner together with an optical CMM probe, geometric elements and free forms can be controlled with pinpoint accuracy. Detailed 3D mapping can be generated to obtain the accurate dimensional characteristics of a damaged part. Ideally, the portable 3D scanner will be one that can be used on any type of part or material, even one with a high degree of reflectivity. Part-to-CAD inspection Part-to-CAD inspection in the aerospace industry requires dimension acquisition on parts of various shapes and complexity. True portability is needed to collect 3D data on the production floor or at a supplier s plant. Acquisition must be complete and detailed to generate a 3D model that is accurate enough to compare to the ideal CAD model. Part-to-CAD 3D deviation can be analyzed with color maps and user-defined comparison points based on the measurements taken by the 3D scanner. Using the high-density data provided by the scanner, the inspector can easily visualize and document complete inspection of the part on all of its surfaces. INDUSTRIES

27 AEROSPACE Production compliance inspection All parts on an aerospace production line are subject to three-dimensional verification, usually requiring a large number of measuring points. Because of their ability to capture data on the shop floor, portable measurement solutions are commonly used for this type of verification. The alignment functionality and automation of the the newest generation of portable optical CMM systems ensure reliability and speed for both systematic and random measurements. Complete inspection of a part can be done in minutes as opposed to more than an hour with traditional inspection tools. For large pieces, a portable CMM s ability to increase its volume is particularly useful. When accuracy is crucial, it is possible to put reflectors on the equipment at locations previously measured with a laser tracker and the optical CMM re-aligns itself locally with the tracker s precision. Tool testing and adjustment As in the automotive industry, design tools (molds, jigs, racks, presses, etc.) should be periodically inspected and adjusted as part of preventive maintenance to deliver the expected level of performance. Portable optical CMMs or a hybrid solution combining scanning and a probe can reduce adjustment times by a factor of two or more for tasks such as setting injection press molds or welding and drill jigs, and testing injection, drawing or RTM composite molds. Dynamic alignment using reflectors previously positioned at predetermined locations ensures reliable measurement in a factory environment. INDUSTRIES

28 CASE STUDY - AEROSPACE Assessing aerospace parts for distortion and conformity The Airbus Group performs 3D optical scans of tooling equipment to assess the possible distortion of carbon fiber composite (carbon/epoxy) parts and to compare a manufactured part to its ideal CAD model. A portable 3D scanner is perfect for these tasks. It has the capacity to scan unorthodox shapes; handle hard-to-scan materials, such as composite parts; and perform scans wherever needed. Thanks to its quick set up and acquisition, ease of use, measurement performance for many types of surface states, and portability, the system enabled us to quickly scan the metallic tooling and carbon fiber composite parts. The equipment s portability made it possible for us to record the measurements right at the manufacturing site, says an Airbus Group structural health engineer. INDUSTRIES

29 CASE STUDY - AEROSPACE Controlling flushes and gaps for aircraft doors Aircelle, a leader in the global nacelle market, wanted a solution that would enable inexperienced operators to control peripheral flushes and gaps (surface points and edges) for inverter doors used in different types of aircraft. The measurement procedure was tricky, since doors needed to be turned over during measurement without losing their alignment. The referencing process was fairly complex as well, since the ball joint axles to be probed were physically hard to reach. Aircelle turned to a portable optical CMM system to handle the job. Dynamic referencing and automatic alignment based on reflectors made it possible to drastically reduce the measuring time and make measurements more reliable by lowering operator-related errors. Using optical CMM technology, Aircelle can now control a new inverter door every 15 minutes, which represents an overall potential of 80 aircraft per month. The system enables us to greatly reduce the operator- or tool-related error rate, as opposed to the measuring arms or manual control jigs we used in the past, says Arnaud Rochon of the Aircelle Methods Department. INDUSTRIES

30 INDUSTRY SPOTLIGHT GENERAL MANUFACTURING Portable 3D scanning and optical CMM align with key manufacturing priorities Automotive and aerospace aren t the only industries driven by the demand for better, faster and less-expensive quality control and inspection procedures -- those priorities apply to almost any good manufactured in practically any part of the world. Another key asset in the global manufacturing environment is flexibility -- being able to adapt to conditions in rapidly diversifying environments. Renaud Anjoran, a certified Lean consultant and Operations Manager of China Manufacturing Consultants, cites four trends for companies with geographically dispersed operations in Asia and elsewhere around the world : Stricter regulations and enforcement Stronger focus on containing costs Working more closely on testing with suppliers and sub-suppliers Fixing problems at the root Reducing the number of suppliers and working closely with key partners to improve quality INDUSTRIES

31 GENERAL MANUFACTURING All of these trends point to the need for better quality control and inspection technologies. The two major areas of emphasis for most manufacturers are first-article inspection and raw casting and forging inspection. First-article inspection First-article inspection in manufacturing calls for acquiring dimensions on parts of various shapes and complexity. Portability enables inspection to be performed where it can be done most efficiently: at the customer s site, on a production floor, or at a supplier s location anywhere in the world. Since the quality inspector or the metrologist wants to evaluate the physical part using its corresponding digital model, the acquisition must be accurate and the 3D model must include all the information needed for a complete inspection. The new generation of 3D scanners can deliver that comprehensiveness and accuracy, while saving huge amounts of time compared to traditional methods. Raw casting and forging inspection Casting and forging operations require dimensional inspections to ensure that the raw casting holds enough material to be machined. A 3D scan allows operators to align the raw part on the machine and orient it to guarantee enough material to create the part. Casting and forging inspection also generates intermediary inspection results for the part to be machined, saving time and money by avoiding machining of non-compliant castings or forgings. Portable 3D scanning is a quick, precise and efficient tool to perform a complete dimensional inspection. Today s most technically advanced scanners can acquire data for any part at practically any location. This flexibility not only saves time in the original inspection, it provides a digital record that enables subsequent inspections to be reproduced much more easily. INDUSTRIES

32 Inspecting heavy equipment in the field GENERAL MANUFACTURING Atlas Weyhausen, a manufacturer of wheel loaders and other heavy equipment, uses a portable 3D scanner to measure components and equipment for quality assurance and for data feedback from prototype parts. The company saves time and money from the increasing number of situations where components must be inspected at their installed location or recorded abroad at the supplier s location. The major benefit of the scanner is easy to see, says an Atlas quality assurance manager. Freeform surfaces are easy to align, along with 3D data. A further benefit is the data feedback into our CAD system. Having digital files for a component is a major benefit. Atlas Weyhausen has digitized the steel construction of a new driver s cab and various paneling sections, for example, and the resulting CAD files are available at any time for quality comparisons. INDUSTRIES

33 Distortion analysis in the plastics industry GENERAL MANUFACTURING Polymer products specialist REHAU is using a portable 3D scanner teamed with an optical camera tracking system to analyze distortion of a component before and after painting. The 3D optical scanner is used to scan injection-molded raw parts in order to make a target/actual comparison of the data and identify any deviations from predefined critical component areas before painting. The injection-molded raw part is then painted and re-scanned. Another comparison of the target/actual data is made in order to identify deviations in the predefined critical component areas. In the final stage, the component distortion after painting is compared with before painting and analyzed. After letting go of traditional measuring technologies and their limitations, our experiences have been positive in every respect, says Matthias Meiler, Prototypes and Gage Construction Team Leader at REHAU. The evaluation software reports can be designed on an individual basis. Our internal clients are extremely satisfied with the quality of the measurement results and are even placing follow-up orders with us. INDUSTRIES

34 GENERAL MANUFACTURING Jig readjustment without the need for realigning AGT, a manufacturer of automated industrial equipment, needed to do quality control on a welding jig for fabricated parts used in building the loading arm of a garbage truck. The company also needed to ascertain the position of other parts on the jig. If AGT metrologists used a traditional arm, every readjustment on the jig by the toolmakers would have resulted in having to realign the measuring equipment. A portable optical CMM system gave metrologists access to automatic realignment and continuous tracking of the part despite any ambient vibrations, ensuring greater speed and accuracy in their measurements. The optical CMM s measurement volume extension function was also useful, since the welding jig was bigger than the basic measurement volume. The measurement volume of the portable optical CMM was easily and dynamically extended without any loss in precision and without the accumulative errors associated with leapfrogging. INDUSTRIES

35 Glossary of 3D scanning and CMM terms 3D scanner -- A device that captures data on the shape, features and alignment of an object for processing in the digital world. Accuracy -- The accuracy of a 3D measurement is determined by the deviation between the actual part and the measured result. It depends on the specifications of the measurement device used and on the quality of the set-up. In 3D scanning, accuracy differs from resolution (see below). Alignment -- In 3D scanning, this refers to the act of bringing all the scans into a common reference system, where data is merged into a complete model. Also called registration. 15% are.stp and.igs. CAD -- Computer-aided design; the act of creating a digital model for design, engineering and manufacturing. The models are based on various geometric entities such as circles, lines and curved surfaces. Typical formats for CAD models CAE -- Computer-aided engineering; the act of digitally simulating performance of objects and assemblies. CAE encompasses simulations such as finite-element analysis (FEA) and computational fluid dynamics (CFD). CAI -- Computer-aided inspection; the use of a 3D measurement tool to compare an as-manufactured part to its CAD equivalent or ideal specifications for quality control, wear-and-tear assessment and other forms of analysis. CFD -- Computational fluid dynamics; a digital process by which engineers can simulate how fluids such as air, water and gas behave within different design, engineering and natural environments. CMM arm -- A coordinate measurement machine that uses a probe or 3D scanner on an articulating arm, allowing users to collect individual 3D data points from a physical object. CMM arm encoder -- An opto-electronic device that detects the incremental lines on a scale to determine positioning. An encoder is also known as a reader head. 1 GLOSSARY

36 CNC milling -- Computer numerical control; computer-controlled milling machines that can create products along multiple axes for improved precision. Digital archiving -- The ability to save models of physical objects in a digital environment, saving time and money. Digital reconstruction -- The act of digitally capturing a physical object in order to rebuild or renovate it close to its original state or at a different scale. Dynamic referencing -- The ability of an optical tracker or self-positioning scanner to ensure that the measuring device is continuously locked to the part by an optical link, providing greater accuracy in factory and field environments and eliminating the need for a rigid measurement setup. FEA -- Finite-element analysis; a digital process by which engineers can simulate how the structure of an object or assembly performs under different environmental stresses. Normal -- In 3D space, a surface normal is the vector cross product of two (non-parallel) edges of a polygon. 2 15% NURBS -- Non-uniform rational b-spline; a mathematical model used in computer graphics and CAD to generate curves and surfaces. Optical CMM scanner -- A 3D scanner tracked by optical CMMs. Optical CMM cameras track passive or active reflectors affixed to the 3D scanner itself and to the part being scanned to dynamically reference them in 3D space. Photogrammetry -- A methodology for extracting high-accuracy measurements from photos of an object or environment. Point cloud -- A set of data points within a coordinate system. In a three-dimensional coordinate system, these points are usually defined by XYZ coordinates, and are intended to represent the external surface of an object. Typical formats for point clouds are.txt,.igs and.ascii. Probe -- A mechanical or optical pointing device attached to a CMM that collects data through touching a point on an object or optically registering the point. Product lifecycle management (PLM) -- The practice of monitoring and managing a product from inception to end of useful life. GLOSSARY

37 Reverse engineering -- The process of discovering the technological aspects of a device, object or system through analysis of its structure, function and operation. In 3D scanning, the reverse-engineering process involves measuring an object and then reconstructing it as a 3D model. Resolution -- Defines the level of details visible in the scan data and measured in millimeters (mm). It can be compared to a screen resolution, which is defined by the number of pixels. A higher resolution increases the number of triangles in a mesh file. Repeatability -- The variation in measurements taken by a single person or instrument on the same item under the same conditions. Self-positioning 3D laser scanners -- Laser scanning systems that use retro-reflective targets as a reference. These scanners do not require external positioning systems because the position of the scanner in relation to the object being scanned is determined by triangulation between the scanner s two cameras and the patterns of the positioning targets. Data acquisition is in real time. Self-positioning 3D white-light scanners -- The scanner obtains its position relative to the physical object by looking at the distortion of the white-light pattern on the scanned part. These scanners obtain their position on a continuous basis in real time as they move over the part. STL -- Stands for stereolithography or standard tessellation language; a file format native to stereolithography CAD software created by 3D Systems Inc. and supported by many other software packages. STL files are used widely for rapid prototyping and computer-aided manufacturing. Triangulation -- The process of determining the location of a point by measuring angles to it from known points at either end of a fixed baseline. The point can then be fixed as the third point of a triangle with one known side and two known angles. Triangle mesh -- The output of self-positioning 3D scanners, this is a mesh from an optimized surface that takes into account measuring conditions and consistency. This is also referred to as a polygon model. Typical formats are.stl,.obj and.sat. An STL file can be used directly for applications such as rapid prototyping and computer-aided inspection or converted into NURBS surfaces for CAD. Sources: Creaform Training Manual for Reverse Engineering 1 From the SME ToolingU website: 2 From Wikipedia: GLOSSARY

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