Hexagon’s Leica Absolute Tracker AT960 is the first fully portable dynamic six degrees of freedom (6DoF) laser measurement system, that represents a single-unit solution for 6DoF reflector, probe and non-contact scanner measurement, as well as 7DoF real-time machine-controlled inspection. It is an ideal solution for applications spanning aerospace, automotive and other sectors.
The Leica Absolute Interferometer (AIFM) enables the tracker to measure a moving target at a data rate of 1000 points/sec with a maximum distance uncertainty of just 10 microns. Scanning accuracy is as low as 50 microns for sphere radius measurement components and as low as 60 microns for spatial length measurement components.
It has an enhanced quick-release mechanism, robust eshock resistance and an in-built tilt detection system that makes mounting the tracker on the fly hassle-free.
Electrical discharge machining (EDM) has long been the answer for high accuracy and demanding machining applications where conventional metal removal is difficult or impossible. The time has now arrived for it to also be equipped with intelligent features. Contributed by Makino
As time goes on, the advances of water jetting continues to happen especially in the case of accuracy and more industries are seeing its viability in the market for faster, more accurate cuts, Syed Shah explains.
While undisputedly the most precise and accurate Measuring Tool, over-reliance on coordinate measuring machines can lead to production bottlenecks. What can you do to avoid this? Contributed by Creaform
Tool setters can lower human error, which is often a major source of delay on the shop floor. By Fredrick Wong, MTP product manager, Far East Renishaw
For any manufacturing company to be a market leader and become more competitive, it is vital to reduce costs, increase productivity, maintain quality, and provide timely delivery. These goals demand a comprehensive approach to manufacturing process improvement.
Eliminating operator intervention is an obvious place to start, as human error is the major source of delay and non-conformance in many factories. One simple and easy way to enjoy the benefit of automation and to maximise the performance of machining operations is the use of tool setting solutions.
Tool Setting And Broken Tool Detection
To ensure that the tool can be brought accurately to the component during machining, we need to establish tool dimensions and record this information in the CNC control’s tool offsets. The traditional method was to make a trial cut and measure the result, but this is time consuming and prone to human error.
Off-line pre-setters are another method, but crucially do not allow the tool to be measured in-situ, and therefore fail to account for dynamic effects, including pull-up where the shank settles in the spindle nose, and tool/spindle run-out.
A tool setter can measure the length and diameter of tools during the machining operation, and store the data in the CNC machine. This means that tools can be introduced to the part and cut close to nominal, avoiding manual ‘cut and measure’ activities and operator errors introduced whilst keying height offsets (a major source of crashes in shops).
The advantage of using the tool setter not only limits to just length and diameter measurement to identify a broken tool, but also provides automated on-machine measurement.
On form tools, a tool setter can check for tool projection and stop the process if a tool assembly has been built incorrectly — vibration and chatter can be induced in tools that are over-extended, adversely affecting process capability. It can also check delicate tools for breakage after each cutting cycle to ensure that a single broken tool does not result in further damage to tools and parts. This increases confidence in unmanned machining.
Accurate & Versatile
The growth in on-machine probing is being driven by technology advances that make machine tool setters more accurate, more productive, easier to use, and easier to afford. Tool setting products are referred to as ‘contact’ or ‘non-contact’, depending on the technology they employ.
Contact Tool Setter
Contact tool setting systems require physical contact between the device and the loaded tool. Systems can be further classified as ‘plunger’ style, ‘probe’ style or as tool setting arms (used for turning centres).
Contact tool setters such as the Primo LTS from Renishaw allows users to set tool length, check for breakage, and compensate for thermal growth on a CNC machining centre.
The tool setter is a single-axis, hard-wired product with an integrated interface for straightforward electrical connection: the hardware can be bolted onto the machine table and be operational with no additional set-up required. It is resistant to swarf or coolant ingress and prevents false triggers caused by shocks or vibration. An integrated air blast provides swarf removal when necessary.
Automated on-machine tool length setting is also faster than manual methods, and the tool setter is suitable for use on small to large CNC machining centres. During the machining process, dimensional accuracy is dependent on a number of variables, including tool length and tool breakage. The tool setter monitors these variables automatically, enabling users to compensate for variations which may occur and benefitting the overall machining process.
Non-Contact Tool Setter
Non-contact tool setting systems employ an optical (laser) beam to detect tool presence. Systems can be sub-divided into ‘fixed’ systems (transmitter and receiver units housed within a single assembly), or ‘separate’ systems having individual transmitter and receiver assemblies. Non-contact tool setters can also check for breaks and/or chips on a tool’s cutting edge.
Examples include the NC4 and TRS2 from Renishaw. The former is a flexible laser tool setting system, with a laser tool setting transmitter and receiver units that can be mounted on separate brackets, or as a single fixed unit. The latter is a single-sided, non-contact, laser-based tool breakage detection device.
The NC4 allows non-contact tool setting and tool breakage detection on machines previously unsuitable for such applications. At 30 mm in diameter and 35 mm high, it allows for probing on machines previously unsuitable for larger non-contact tool setting and tool breakage detection systems. Depending on system, separation distances and mounting, it can measure tools as small as 0.03 mm in diameter at any selected point along the beam, and check for breakage.
The TSR2 allows detection of solid tools on all sizes of vertical and horizontal machining centres, all gantry machining centres and multi-tasking machines. The single unit can be mounted outside the working environment, saving space on the table.
Once positioned within the machine tool, cutting tools pass through the TRS2 laser beam in between cutting and tool change operations. When broken tools are detected, the machining process is stopped or a replacement tool is substituted via the automatic tool changer. The setup has potential for scrap reduction and improvements to process control.
Munjal Castings is part of the Hero Group, and caters primarily to Hero Majestic in the automotive industry in India. The company has two plants where it manufactures aluminium die cast components using 20 machine tools. The aluminium and zinc die cast company supplies 600 tonnes of castings each month with a turnover of 1.5 billion INR (US$22.9million), and key customers include Hero Motor Corporation Limited, Suzuki Group, Hyundai, Hero Cycles, Nissan, Tata, GM, and Daimler Chrysler.
P L Arora, senior vice president of Munjal Castings, said: “Maintaining quality, cost and delivery within stringent deadlines is our company’s unique selling point, which has helped us to stand apart from others. Daily, we supply 200,000 castings with 150 different component types to the automobile industry.”
A major challenge to overcome was frequent tool breakage, which caused delays in production and led to high levels of scrap and financial loss in terms of materials and time. Sixteen units of TRS2 systems were installed at Munjal Castings to address this challenge. The TRS2 determines whether a tool is present by analysing reflective light patterns and ignores any that are created by coolant and swarf, thereby eliminating false indications of a broken tool.
Machines with the contact tool setter installed saw overall equipment effectiveness (OEE) increased from 50 percent to 76 percent.
Following this, the target is to increase the OEE to 85 percent. Previously, 250 finished components were produced daily on each machine. After installation of the systems, production increased to 270 components per day.
Munjal Castings’ machines with the contact tool setter installed saw overall equipment effectiveness (OEE) increased from 50 percent to 76 percent
The rise of scanning technology is changing the landscape of quality assurance in the metalworking industry. Just what is it that makes scanning such a revolutionary measurement technology? By Mark D’Urso, product manager, marketing, Hexagon
Non-contact scanning for measurement and analysis is growing in importance every year right across the world of materials fabrication, finding exciting new applications across a widening range of industries and settings.
In many places, scanning can be the route to massively increased speed and efficiency while delivering a new type of data to solve problems that are beyond the reach of traditional touch-probing methods.
Look, Don’t Touch
The most superficially obvious advantage of scanning over touch-probe measurement is the ability to take accurate measurements without physically touching the part being measured. The range of industries manufacturing products that require quality assurance processes applied to materials with a delicate or easily damageable finish is wide, and for such applications scanning offers a non-contact solution that traditional touch-probe CMMs cannot match.
And it is not just the point of measurement where scanners present a non-contact benefit. Readying a part to be scanned needs only a stable platform, with no clamping required, ensuring measurement accuracy. And while in the past applications for scanning were limited by the need for target markers placed on the product to be measured, the technology has by now progressed sufficiently that extremely accurate measurement results can be collected with no need to touch the component at all outside of initial placement and reorientation.
Such reduced preparation requirements for successful scanning introduce what is perhaps the key benefit of scanning over probing: vastly reduced measurement process times.
Scanners have the capacity to capture huge amounts of data very quickly. The exact speed at which a scanner can collect data varies with the exact type of scanning technology used, but compared with one-point-at-a-time touch-probe measurement, the point-cloud data collection of even the most basic scanner is on another level.
Even entry-level scanning solutions can capture up to 50,000 data points every second, while with the very latest laser scanning technology, that number rises to three quarters of a million.
What this comes down to is the potential for increased speed and efficiency in data collection. Every important data point needed to accurately map, for instance, a car door panel, can be collected in less than two minutes with the right scanning technology. Performing the same measurement process only 10 years ago would have presented a long task, requiring not only more measurement time but also a significant amount of preparation time in order to ensure all the most important measurement points were taken.
Even then, the data collected by touch probe would be a level of abstraction away from a proper representation of the part in question. Scanning on the other hand is able to produce a picture of a component, cataloguing every undulation and deviation in form.
A Different Type Of Data
That brings us to the other clear improvement that scanners deliver. The huge amount of data they have the capacity to collect has deeper implications than merely the ability to record the same old measurements at a faster rate. This quantitative increase in data actually translates to a qualitative difference as we move from a predefined set of key data points to a multi-million-point data cloud, representing a fundamental change in the way that data can be used.
The result is the potential to almost instantly create a three-dimensional model of the object or surface being scanned. This allows for geometric and dimensional part analysis that would be all but impossible to replicate through touch-probe measurement. With scanning technology, we can create two-dimensional cross section mappings and perform flush and gap inspections based on a range of useful geometrical definitions.
Going even further, high-volume scanning data can be used as a reverse engineering tool, useful from competitor product analysis through to the manufacture of spare parts for which no model exists, such as old aircraft components. Such functionality also allows for the update and re-design of existing CAD models based on real world production data—it is even possible to compare to CAD models in real-time with some technologies. Some scanners are even able to record accurate colour mapping that is ideal for reporting and documentation purposes.
The range of applications to which scanning technologies are well suited is extensive, from inspecting panels during installation processes to in-depth defect analysis of composite parts. With an accurate three-dimensional model and appropriate software solution, it is now even possible to carry out virtual assembly of prototype parts for the purposes of accurate interference analysis.
Accurate surface models and cross sections are extremely useful in the aerospace and wind power industries, where improving the efficiency of turbine blades is highly important. Portable scanners also offer an interesting solution for preventative maintenance of casting dies; a quick shop-floor “health check” with a scanner can avoid costly scrapping unless absolutely necessary.
With scanning being so easily applicable within portable measurement solutions, its benefits are not limited to controlled quality room environments. Scan data can easily be collected on the shop-floor, in-line within fabrication processes or even from within a mid-installation aircraft fuselage.
Portable scanning technology currently comes in several ‘flavours’, each with its own benefits and points of interest. Laser line scanning offers accurate and reliable data acquisition at high-speed across almost any surface type. This technology can be used in conjunction with a laser tracker to perform scanning tasks over large areas, and the lack of moving parts makes such laser tracker and scanner combination systems perfect for robot mounting for in-line measurement tasks.
Alternatively, laser line scanners can be found mounted on portable measuring arms for extremely fast and accurate measurement of smaller parts and surfaces, with the arm acting as a global reference system for the scanner system.
A variation on this technology is “flying dot” laser scanning, which is flexible enough to scan across multiple surface colours and materials with no settings adjustments. It is also unaffected by ambient light and offers adjustable laser line width and scan point density settings along with a larger stand-off for easier measurement.
The other major portable scanning technology comes in the form of structured light scanners, such as white light fringe projection and photogrammetry systems that offer extremely high accuracy and point-cloud resolution for small-volume measurement. While the required target markers can be slightly time consuming to position, they allow for better lines of sight by repositioning the scanner without restarting the measurement process.
With a combined fringe projection and photogrammetry system, it is now even possible to visualise the results of a measurement directly on the object being measured, offering a visceral real-world representation of your data.
The Future Of Metrology?
There are some factors that balance all these benefits when it comes to comparing scanning with traditional touch-probe measurement techniques. Perhaps the most important one is that the trade-off for increased speed and size of data collection when it comes to scanning is in terms of accuracy. This is the area in which the conventional touch-probe based CMM still wins the argument. If accuracy down to fractions of a micron is central to your measurement needs, scanning technology is not yet ready for you.
The other key argument against implementing scanning technology yesterday comes down to cost. New scanning technologies are unsurprisingly more expensive than probing solutions when controlling for equivalent levels of accuracy. As always when adopting new tools, a key part of the investment decision comes down to value, and while the benefits of scanning solutions represent a bargain for many users, for others the investment is too much—for now at least.
But for the wide range of applications that do not require data at such high accuracy levels and for which the requisite investment is justified, the benefits of scanning are absolutely clear: Scanning is the metrology technology of tomorrow.
High-volume scanning data can be used as a reverse engineering tool
From inspecting panels during installation processes to in-depth defect analysis of composite parts, scanners can be used for many purposes
A rapidly changing technological landscape necessitates a leap in the quality of the current crop of Coordinate Measuring Machines (CMM) both in accuracy and the level of automation. Contributed by Nikon.
In today’s inspection methods during automotive assembly, it is important for automotive assembly plants to continuously monitor process quality during the manufacturing process. Locations of holes, slots, studs, welding lines and other features need to be measured on the vehicles in Body in White (BIW) assembly. Flush and gap of doors and other hangers also need to be monitored and verified. These inspections ensure that vehicles are built within the stringent tolerances set by automotive manufacturers.
These measurements in the past have been primarily performed offline by either horizontal arm CMMs or on the production line using dozens of sensors individually aimed at each of the features that are to be inspected.
Although CMMs provide highly accurate absolute measurements, they tend to be slow and require an expensive metrology lab which limits their use to offline applications. A large amount of time is required to remove the vehicle from the line, fixture and align it on the CMM and then perform the time-consuming measurements. At best, two vehicles can be inspected per shift on a CMM. This is a very small sample considering that over 1,000 vehicles can be built each day in a single automotive plant.
Traditional inline systems can have over 100 fixed sensors. These fixed sensors are demanding to install and maintain and do not provide ‘absolute measurements’ of the features in the car’s coordinate system. In addition, most assembly lines now are ‘flexible’, meaning that they can produce more than one type of vehicle. Fixed sensors cannot be used between different vehicles styles; every vehicle requires it’s own custom set of sensors.
Recently inline inspection systems have been moving towards robotic based solutions which are flexible but rely on the robot for positional accuracy which limits their performance.
The Laser Radar
Nikon’s Laser Radar provides a unique alternative to the shortcomings of the traditional inspection methods. The device performs automated, highly accurate, contactless measurements by using a focused laser that is controlled by precision azimuth and elevation drives.
To perform a measurement, the device only needs a fraction of the laser’s signal to be returned giving it the ability to measure almost any surface, including highly reflective bare body panels as well as shiny painted surfaces. This robust measurement ability means that the device can be used for both BIW and end of line flush and gap inspections on finished cars.
In addition, the device also has a large measurement range (up to 50 m for the MV350), allowing it to easily measure objects that have the size of cars, trucks, and other large vehicles.
Line Side Inspection
Laser Radar inspection stations can be installed line side. A station consists of one or more laser radars mounted on 6-axis industrial robots. This type of robot is common place in automotive production facilities, is very robust and can easily handle the payload of the device.
The robots are used to automatically reposition the device so it can inspect areas that are hidden from the line-of-sight of a single device location. For example the door frame or other body panels could be blocking the line-of-sight to some features on the floor pan; repositioning the device to an alternate location will make these features visible again without the need for multiple sensors.
After the robot repositions the Laser Radar, the device automatically measures alignment points on the vehicle or pallet. This occurs each time the robot moves the Laser Radar, guaranteeing that all measurements are collected in vehicle coordinates and ensuring measurement accuracy is independent of the robots ability to repeatedly position the device.
In each location the device can measure dozens of features on the vehicle. These measurements are pre-programmed in the inspection software directly from the vehicle’s CAD model. After the initial programming, data collection and reporting is fully automated.
Unique inspection scripts can also be written for each vehicle style and model made on the production line making the inspection station completely flexible. Adding vehicle styles in the future only requires re-programming of the inspection plan and does not require any physical changes or new hardware.
The interaction of the device, robot, and analysis software are fully integrated; the inspections are completely automated and do not require manual intervention during runtime, improving both the speed and quality of the measurements over traditional methods.
Bringing Accuracy To A New Level
The Laser Radar is a programmable contactless measurement system and has an accuracy <0.1mm over the volume of a car. It can be fully automated and can directly measure holes, studs, bolts, along with many other features accurately from a large standoff, eliminating the risk of ‘crashing’ into the vehicle.
The device measures up to 2,000 points / second making it suitable to not only measure features but also scan surfaces. The ability to offline program the device makes it ideal for inline inspections; different vehicle models on the same assembly line are simply a new inspection program.
Accuracy in the manufacturing of components in the steering wheel system is essential in enabling optimal steering performance. Contributed by Carl Zeiss
Automotive supplier TRW Automotive manufactures braking, steering and suspension systems, as well as occupant protection systems and vehicle electronics. The company supplies parts for around 250 different vehicle models and more than 40 car makers. Around 1,000 of the company’s 65,000 employees produce steering systems in the Polish cities of Bielsko-Biała and Czechowice-Dziedzice.
Jarosław Muchajer, a quality manager at the company, is responsible at the company’s Bielsko-Biała site in Poland for the one of the most complex and expensive component of a vehicle after the engine: the steering system.
If the measurement results exceed the tolerances of just 0.1 micrometre, production has to stop. This safety measure can quickly result in exorbitant costs. This led the company to look for precise measuring equipment and 24-hour support from the manufacturer.
Looking For A Solution
When the Bielsko-Biała factory opened in 2012, plant managers drew on their own experience when the time came to select the coordinate and surface measuring systems.
They selected a surface measuring instrument from Zeiss, called the Surfcom 5000. Using five lasers on its interferometer, the unit was able to measure with accuracy levels of around 0.31 nanometres on average. The unit also has a ratio of the measuring range to resolution of approximately 42 million to one.
Steering Systems Market
According to a market report by research firm MarketsAndMarkets, the steering market is projected to grow at a CAGR of 6.47 percent from 2016 to 2021, to reach US$42.77 billion by 2021.
The Asia-Oceania region is estimated to lead in the market in terms of growth rate during the forecast period. The increasing demand for automotive comfort and safety is a key driver of the steering market.
The majority of new cars sold today feature Electric Power Steering (EPS).
Asia-Oceania comprises some of the fastest growing economies in the world, including China, India, and Indonesia. The region has the highest vehicle production in the world, due to its sizeable population and increasing disposable income. The growing population, increase in per capita income, and improving standard of living have contributed to the growth of the automotive industry in Asia Pacific.
The key automotive market in this region is China, which produces the highest number of passenger cars in the world. Given that the steering market is directly dependent on vehicle production, Asia-Oceania has emerged as the fastest growing market for steering systems, in terms of value as well as volume.