Quality boosted and zero rejects with vision from Cognex!

Quality boosted and zero rejects with vision from Cognex!

Mayer & Co., a global leader in its field has found the solution to their production problems in Cognex vision systems. While it’s something we all do possibly several times a day - opening or tilting a balcony door or window, most of us are unaware of the technology behind it. Mayer & Co., known to experts worldwide as MACO, is one of the three market leaders in the manufacture of rotary and tilting hinges for windows and doors. Using cameras from Cognex and support from Buxbaum Automation, they were able to find the perfect solution to optimizing their production process. Rejects have been reduced to practically zero. Motivated by their success with the Cognex DVT 510 series, the MACO engineers will be relying on Cognex quality for other production areas and lines in the future especially considering they were the first company in the industry to be certified to DIN ISO 9001 by the AGQS.

The components are manufactured exclusively at the company’s main plants in Salzburg and in Trieben. MACO distributes its products through an extensive network throughout the world, although Europe is its dominant market. Both plant I in Salzburg – which houses the product development centre as well as the company’s headquarters – and plant II in Trieben have state of the art tool making facilities. Special machines such as assembly equipment are designed and produced in-house.  MACO’s success has always been based on the quality of its products. Reflecting their assumed responsibility to the customer, all products undergo stringent monitoring and improvement processes, from development to production to delivery.

The right vision system for the task at hand
The company faced a particular challenge in that they required the vision system in place to detect whether the work piece has been inserted with the correct side facing upwards. If not, the camera immediately sends an error message to the machine controller. A separate mechanism then rotates the gear to the correct position and it can then be processed as normal.  All kinds of vision systems had previously been tested underlines how difficult the problem was for MACO to resolve.  Satisfactory results could not be achieved for a period of two years.

In order to solve the problem, DVT 510 camera sensor from Cognex was recently fitted on the machine. A recess in the gears allows the camera to detect immediately whether the piece is facing the right way up.  “With the camera sensors from Cognex and support from Buxbaum Automation, we were finally able to find a perfect solution to our problem. Rejects have been reduced to practically zero. This has ultimately convinced our process managers to make further investments in this technology”, confirm the visibly satisfied automation engineers from MACO. “The technical capabilities of the Cognex DVT 510 – such as the Ethernet port, compatibility with standard bus systems, remote operation in real time, CMOS image chip, 32 MB DRAM data memory, 8 MB Flash memory and the Intellect camera software – were crucial in overcoming the issues we faced. The software is easy to operate yet provides optimum scope for adjustment. At the end of the day it was not the price that mattered most to us; it was quality and expert advice”, they continued.

Motivated by the success with the Cognex DVT 510 series, the MACO engineers will be relying on Cognex quality for other production areas and lines in the future.

About Buxbaum Automation
Buxbaum Automation is one of the leading suppliers of industrial communication technology and vision systems for manufacturing industry. With its international partners Woodhead Software and Electronics, Contemporary Controls, Trebing&Himstedt, ProSoft, Softing, Cognex, Büchner Lichtsysteme, Vision Components, Tamron and Fujinon, the Eisenstadt-based company can offer a broad range of high-quality products in the areas of network technology, field bus systems and vision.  Backed up by process know-how, years of experience and expert staff, Buxbaum Automation is ideally placed to supply complete communication solutions for industrial applications.

Precision inspection for white goods

Precision inspection for white goods

Prettl
Appliance Systems Deutschland GmbH (PAS) is using In-Sight vision
systems from Cognex to guarantee quality in their production process.
Every control panel manufactured at their plant must first be put
through its paces in an intricate production process as they are
destined for the world’s white goods industry. Not an easy task
considering the reflective surfaces, variety of colorus and multiple
features needing to be fully inspected. In-Sight vision systems proved
up to the challenge.

In-Sight meets the colourful challenge posed by white goods

Prettl
is one of the world’s leading suppliers of system control panels and
cables for white goods. They develop state-of-the-art control panels
for washing machines and driers. The front control panels for high-end
washing machines manufactured by Prettl are masterpieces beautiful,
multifunctional and reliable. With stylish curves, and glossy finishes,
they come in many different colours. Equipped with a wide range of
variable functions, the company’s control panels are ideal for any type
of application; coloureds, whites or delicate fabrics.  Quick wash
cycles, gentle wash cycles and spin-drying at any speed are also
standard features.

Two companies who have been implementing
projects in tandem for many years were charged with creating the
inspection station and developing and assembling the production plant:
Weber Konstruktion Maschinenbau GmbH, Aschaffenburg (Germany), and
Weber Systemtechnik, Wetzlar, who is a member of the specialist global
Cognex partner integrator network (PSI) in Germany.

The challenge - accurate inspection of multiple positions and colours

The
project team decided to use Cognex In-Sight technology on this project
because it has already proven itself in many other large projects
previously carried out together by the two companies. “It was essential
that the quality inspection system be able to cope with the
multifaceted and high-quality design of the Prettl control panels”,
says Alexander Kobras, managing director (technical) of Weber
Konstruktion. “The control panel is bent into shape and the lettering
is then applied but the critical point is that the controls, the LED
indicators and the lettering can all be positioned differently on
different product variants and, above all, there is a wide range of
product colours, which makes an intelligent inspection station with
reliable camera technology essential,” continues Kobras, an expert in
the field of production technology.

This was made possible by the
use of a six-axis robot arm which holds the control panel and moves it
into all of the checking positions required by the camera. “In-Sight
not only checks that the various features are present and positioned
correctly, it also checks their quality,” says Thorsten Rauber, head of
the measurement and checking systems division of Weber Systemtechnik.
The inspection criteria include the position of the features, their
completeness and the quality of aspects such as the pad printing. There
can be occasional problems with lettering that is not complete, is
smeared or is applied twice.

A vision solution for multiple inspection scenarios: reflective surfaces and colours
The inspection system, consisting of Cognex In-Sight technology and the
user interface of the flexible inspection software from Weber
Systemtechnik, can easily adapt to a wide variety of colour and
brightness contrasts. The surface finish of the control panels ranges
from black, white, red and blue through to silver and many other
high-lustre finishes, which sometimes cause strong reflections. One of
the specifications for the development of the inspection station was
that the checking process should be performed as quickly and easily as
possible without the need for extensive training of staff. “Inspection
of all of these different scenarios with just one hardware
configuration, one camera and one source of illumination was one of the
main challenges,” says Thorsten Rauber.

The
vision system also needs to be capable of detecting any surface damage
present, such as paint scratches, which was a real challenge for the
Weber team due to the wide variety of possible surface damage.

Complete product traceability included!
In addition and depending on the model and customer requirements, the
system can read a barcode and a data matrix code and this product data
can then be used for internal process-related tasks such as ensuring
maximum traceability of production results.
The functions of the control panel are simulated by means of electrical
communication between the vision system and the circuit boards of the
control panel and the LEDs are activated so that a visual check can be
performed. When a defect is recorded by the In-Sight system, the system
stores the picture with the associated data on the internal database. A
worker can then access the picture and the data and decide on the next
steps to take even before he or she takes a look at the individual
item. This saves time and speeds up working processes.

In-Sight
demonstrates its strengths impressively. Both Alexander Kobras and
Thorsten Rauber appreciate the development efforts made by Cognex. In
particular, the algorithms work much better than those of competitor
systems. Real-time process control, high-speed image processing, highly
precise object localisation and easy operation without programming
expertise have made the control station created by Weber Konstruktion
and Weber Systemtechnik a trusty assistant of PAS.

Verification and inspection of parts

Robot cell equipped with Cognex vision keeps knives sharp

SIR, an Italian machine builder specialized in robotics, has created a special cell for knife grinding and surface finishing using powerful PatMax® tools from Cognex

SIR is an Italian machine builder located in Modena. They have recently conceived and produced a cell that is dedicated to metalworking. The objective is to re-work worn out knives, which after being grinded and used have lost their original shape.

The peculiarity of this application is that it allows the refurbishing of different types of knives, whose blade shape is unknown, to their original conditions. In order to carry out a correct grinding, it is not possible to do a rough estimate of the degree of the knife’s usage and to assume a calculated path starting from the original one. Knives are usually grinded manually and the theoretic shape does not correspond with the real one. For this reason the use of a vision system has become necessary in order to estimate in real time the right profile of each knife.

The cell working process consists in the robot’s taking the knife and positioning it under the vision system in order to get the shape. Then both sides of the blade are grinded separately. Subsequently the knife is scoured in order to make the blade edge smoother and homogenous. At the end, the cold trimming operation eliminates any tailings due to the grinding from the blade. When this is over the knife is placed in a basket that is similar to the one from which it was taken.

The vision system cycle consists of a first recognition of the type of knife handle, as not all handles are the same even for the same kind of knives. Afterwards the blade is scanned in order to calculate all the necessary points to reconstruct the original shape. After getting the profile, the execution of the first analysis of the blade serves to discriminate all the anomalous points and verify the presence on the same blade of too many deep niches in order to continue with the normal working cycle.

Once the first analyses are finished, the profile is standardized in order to bring the knife back to its original shape. Once the standardized profile is obtained, the execution of the second analysis cycle allows verification of the degree of blade use in order to correct the working parameters such as speeds and incidence angles. Next step is to decide what point to start the work from in order to avoid ruining the knife handles, in case of very damaged blades.  Even the finishing points are decided from time to time, after having taken into consideration the angles and the shape of the knife tip.

The robot is made up of a Cognex VPM-8501 image acquisition card with VisionPro® using PatMax software tools. An analogical resolution standard camera is connected to the card and the front or back system. Lighting can be driven alternatively depending on the analysis type to be carried out. The communication with the robot is via Internet and thanks to the transmission of files, quotes and angles in which are described all the processes of grinding, scouring, cold trimming that he have to be carried out as well as the beginning and the end of the working process. The software leverages simple screenshots for the regulation of the research parameters.

This unique application is having great success as it allows the system to acquire an outstanding decision skill level, which is demanding, considering that the production is random and that no knife will be like another.

Part measurement, inspection and quality control

IN-SIGHT VISION SENSORS FROM COGNEX ENSURE 100% CONTROL AND A FAILURE RATE OF LESS THAN 10 PPM AT PHILIPS

The Philips factory at Chartres, France, specialising in automotive lighting systems, is one of the biggest factories in the world to manufacture indicator lamps.  It supplies bulbs throughout the entire world.
Philips Chartres subjects its production to 100% inspection and control. Each element of the bulb (the base, the filament, the glass and so on) is checked both for dimensional accuracy and appearance.  Philips’ aim is to achieve a failure rate of less than 10 ppm. With a production rate of 8,000 bulbs per hour, only an industrial vision system would be capable of reliably carrying out this type of control.

Vision system control applications for glass products are always complex, because of the natural variations in shape of such components.  As its industrial vision system requirements increased during 2000, Philips decided to test a number of different vision systems on the market, with the aim of selecting a solution that would become the standard for all future applications.  The target was to cut training and maintenance costs for these systems.  Philips eventually decided on Cognex In-Sight® sensors, because of their ease of implementation and the performance of the vision tools.  Today over 20 In-Sight systems have been installed at the Chartres factory.

Due to the cost of each of the bulb components, there is good financial justification for implementing an inspection system part way through the manufacturing process, to identify defect parts before additional value is added to them.  This limits the reject rate of complete bulbs.  For this reason the Chartres factory is equipped with both in-line and end-of-line inspection systems.
In 2003 the T10 lamp production lines were equipped with a final inspection system to control lamp appearance. The initial objective was to guarantee that lamps have an optimum service life.  A secondary aim is to ensure that these lamps during operation, have the perfect shape and geometry, enabling the OEM or automotive manufacturing client to fit them into vehicles automatically.

For this reason every part of the lamp has to be positioned within precise tolerances.  The vision system must be capable of carrying out this inspection, but at the same time taking into account normal variations in the glass components.   These variations can sometimes be fairly major, due to the nature of the glass material.  The way the glass, the filament and the metal filament supports are assembled, means that each bulb has its own characteristics.  At the inspection point each one will differ from the previous one, and from the following one.  The bulb image will also vary depending on the colour of the glass used, or reflections from its metal parts.  So it is a real challenge to the system to accept these major variations caused by the nature of the product, and to reject only those bulbs that really are faulty.

The application uses two Cognex In-Sight systems:
- the first inspects the lamp cap,
- the second inspects the cap + bulb assembly. (Here the camera uses a clever prism system, which means that the product can be inspected from two aspects.)

The images shown below illustrate how the products being inspected can vary.  The bulb shown in the left hand image is faulty, because it is too far out of centre.  But, even though the metal filament is barely visible, the bulb inspected in the right hand image is OK.  The full capability of Cognex vision tools, such as PatFind®, are required to reliably locate these check points and to make the right accept/reject decision.

Cognex vision tools meet the requirements of this application perfectly.  The geometric tools (the detection of edges – straight line or arc of a circle – segments, construction lines, circles and intersections, the calculation of distances between points or between a point and a straight line) are used many times in this example.  They allow the symmetrical axes of the product and the distances in relation to the axes to be calculated.  They also enable many set-up operations to be made in an extremely flexibly manner, and the item’s dimensions to be recorded.  The flexibility and robustness of the PatFind tool means that variations of the glass can be correctly taken into account, both with regard to geometry and the shade of colour.

Philips really appreciates the fact that Cognex systems are so easy to use.  It has meant that their staff have mastered the vision systems quickly, and maintenance costs have been cut.  “There’s no need for us to employ a machine vision system expert” said Jean Leriche, Industrial Projects Manager - “Our knowledge of the process has enabled us to optimise the application.”

Now that the system has been running for a few months, Philips is very satisfied with the operation of the system, and is encouraged to expand the vision system applications at its site.  One example, is the use of networking facilities provided by the Ethernet interface incorporated into In-Sight 1000 and In-Sight 4000 sensors for tool optimisation, image recording of faulty products, and traceability.  Projects are currently under way to study new applications on other products.

Vision – the innovation necessary to sort 180,000 parts per day

Vision – the innovation necessary to sort 180,000 parts per day

Innovative German machine builder, Schuster-Präzision found themselves faced with the challenge of providing a customer with a machine that could accurately sort 180,000 drill parts every day. They chose Cognex vision systems as the robust and innovative component that would make the difference on their sorting machines.

Many metal processing companies use their specialised machines for the production of what accounts for approximately 97% of all drill components produced globally. These range from large masonry and metal drills right down to fine drills for medical use. As a manufacturer of special machines, Schuster-Präzision, Germany, ensures that their customers can assure the smooth running of various processes such as sorting, turning, milling and cutting parts to the correct length. Quality assurance and automation technology are of the highest priority. When it comes to the sorting of large numbers of parts, it is essential that the systems performing the task are completely reliable and capable of enduring the rigors of continuous operation.

Key component – In-Sight vision systems

One of the most important components of these special machines are In-Sight vision systems from Cognex. For example, one of Schuster’s largest customers, who manufactures 180,000 drill pieces per day, can count on 100% accurate sorting thanks to these precise sensors.

In the first step of the sorting process, the container of the machine, which is equipped with an In-Sight 5100 from Cognex, is filled with several thousand drill components. A sliding mechanism then moves the individual pieces down a ramp and on to a conveyor line.

In-Sight guarantees correct part positioning and orientation

The In-Sight and a special gripper ensure that the heads of the drill bits point in the correct direction. With its precise sensors, the system detects the positions of the parts and transfers this information to the microprocessor of the container. If a drill component is positioned correctly, it is simply transported further on towards the output area. If a drill piece is not positioned correctly however , the In-Sight informs the gripper who grabs it and positions it correctly so it can continue to the output area with the other pieces. This is a simple process but it requires reliable machine components because of the large numbers of parts being processed.

In-Sight - robust vision for a tough industrial environment

As in many other areas of the metal processing industry, machines must be robust in order to achieve required precision, reliability and to operate round-the-clock. The vibrations caused by mechanical conveyors, jolts from pneumatic systems and the dust in the production areas present quite a challenge to precision machinery. Vision systems from Cognex are built to be particularly robust so that quality standards are always maintained, even under the most difficult conditions. Equipped with die cast housings, lens protectors and M12 connectors with seals, they can withstand even the roughest industrial environments.

The indispensable tool

Today, the In-Sight 5000 family is indispensable for Schuster-Präzision because it guarantees high-quality production systems. General manager and company founder Helmut Schuster can no longer imagine his special machines without Cognex systems, “With Cognex, complete reliability, innovative technologies and excellent service allow us to meet our quality standards 100% of the time and allow us to plan our business effectively. Another benefit is that In-Sight can be operated simply and reliably.”