Machine vision is the ideal tool for robot guidance,
allowing visual inspection of the robot working area as well as guidance
based on the detected position of a product or component. Vision
systems can be used to identify the product in pick and place
operations, for example using OCR, barcode reading or other visual cues.
As end-of-line packing is increasingly automated, many
factories have discovered that end-of-line packers often provided a
final quality inspection of which managers were not aware. Vision
systems can carry out this function in addition to robot guidance. In
addition, vision systems never tire, never slow down and are consistent
between shifts.
MVT is working with a logistics company to provide robot
guidance for a supermarket distribution centre. The requirements include
identifying the type of crate, the number of crates in the stack and
position of the top crate
A further requirement is to read barcodes on the crates to
identify the contents. One of the advantages of modern vision systems is
that their large number of tools allows ‘multi-tasking’: the ability to
carry out several tasks rather than just one. Increasing processor
speeds mean that this can be carried out within the cycle time of the
rest of the line.
The printing industry is a natural home for vision
systems; high speed lines can take advantage of ever-faster processing
speeds allowing on-line inspection. MVT has been involved in the use of
vision systems for print verification and optical character recognition
(OCR) in numerous industries.
Vision systems are able to perform print verification, which
may incorporate optical character verification (OCV), and is usually a
high speed process with applications to inkjet, laser, pad and screen
printing processes. Typical installations are checking print quality,
sometimes in conjunction with a changeable target, for example serial
numbers. Installation usually requires a ‘linescan’ camera. This has a
single row of pixels and takes advantage of the movement of the line to
build up an image. In this way, camera installations take up minimal
space on the line.
Print verification techniques can be applied to other fields such as printed circuit boards and automated assembly processes.
MVT are happy to provide trials and to discuss customer
requirements to ensure that the final system meets all of the job
specification.
Production engineering is well-placed to take advantage
of a large number of vision system tools developed for other
industries. As well as tolerance-checking on machined parts it is also
possible to check for defects in parts such as scratches, cracks and
missing/extra components.
There are also opportunities to use OCR (optical character
recognition), data matrix (2-D barcodes) and 1-D barcodes to allow part
tracibility throughout the production process and into customer usage.
This allows faulty batches to be traced even after they have been
delivered to customers and has become widely-used in the aerospace and
automotive industries, where safety-critical components must be
tracable.
The machine vision industry has produced a number of vision
systems tools for the electronics and semi-conductor industries in recent
years. As such, the vision systems applications for these industries are
numerous and well-proven. However, as the computing power available in PCs and
smart cameras increases, what was once a specialist branch is becoming more
mainstream with the attendant cost reductions.
The electronics industry can benefit from machine vision in
a similar way to both the pharmaceutical and print industries. High speed
production lines and microscopic details can be verified by vision systems
on-line. On a macroscopic level, a vision system can check batch numbers on
chips, read datamatrix codes (2D barcodes), ensure that all components are
correctly positioned and no foreign bodies are present. Other applications
include printed circuit board verification, flaw detection (such as scratches
and foreign body detection) and LCD screen fault detection.
MVT has a
great deal of experience with automotive vision systems, having worked with
major automotive OEM component suppliers. Typical vision systems applications
include checking that manually-assembled automotive components are complete and
correct and measuring machined parts to check that they are within tolerance
(non-contact gauging). It is not unusual for automotive dimensional gauging to
be carried out using moving cameras (for example on a robot arm).
Our experience
Automotive companies increasingly demand 100% quality checks from suppliers: vision systems have an important role to play.
It is
possible to check for colour matching, character recognition for batch or
product codes and barcode or datamatrix (2D barcode) decoding. The use of
datamatrix marking in the automotive sector is becoming increasingly prevalent
as manufacturers and suppliers fight counterfeit products and require traceability
of defective batches. Datamatrix marks are able to hold far more data than is
possible with barcodes and in a much smaller, permanently-marked area. They
also incorporate a degree of redundancy to account for any damage that may be
incurred during the lifetime of the part.
Automotive
components being checked include suspension units, air springs, automotive
interior fittings and even tyres. In addition to quality and dimensional
checks, vision systems can be used in robot guidance and product identification
for a ‘pick and place’ operation. The identification may be in the form of
product features, e.g. shape, or from labels using datamatrix, barcode or text.
Some of our customers like to use this functionality as an extra check when
various products or variants may pass down the same production line.
Vision systems are becoming increasingly important in the food
industry as end-of-line packing is being automated. Food suppliers have found
that packers used to check the quality of goods before they were packed;
automation has brought about a requirement for vision systems to take over this
function. We are now in the position of being able to apply vision system techniques,
label inspection and character recognition to the food industry. This has
allowed customers to improve their quality and reduce wastage.
Our experience
MVT has built a relationship with two companies in the food industry. Western Mechanical Handling are specialist manufacturers of food handling systems.
In a recent application we provided the vision for a ‘pick and place’ unit
for loose pork pies. Due to the irregular nature of the pies it was found that
they were sometimes damaged by the picking mechanism. By incorporating vision,
the precise location of 48 pork pies on a tray was verified and measures could
be taken to reduce wastage. This is one of the applications that vision systems
have been used for extensively in other industries.
Other potential applications include checking the presence or absence of
labels, character recognition (for example date code recognition, product
type), print verification and the identification of errors in packaging. This
can include identifying food trapped in seal areas and seal integrity on boxes.
Quality checking of food items is also possible, this may involve a
presence/absence check of a number of items or checks on the colour, size or
shape of items. With respect to cooked items, colour may indicate burnt or
uncooked areas; size and shape measures can indicate mis-handling. All of these
checks can help to improve quality and reduce wastage.
The pharmaceutical and medical device industries have been
served by us since the company was founded. We can provide 21 CFR Part 11 ready
solutions. The pharmaceutical and medical device industries offer an ideal
application to vision systems.
Vision systems can check 100% of products, even on high speed lines, allowing statistical process control (SPC) to be used to monitor any variations in quality. Applications include print recognition and verification (OCR/V), including verification of date/lot codes, checking the presence of all components and colour checks in pharmaceutical devices.
In addition to standard vision systems, MVT is able to supply customised solutions and specialist vial readers for the pharmaceutical and medical industries . These are able to read datamatrix marks (2-d barcodes) from a complete tray of 96 vials. The advantage of this type of automated reading is that vials can be marked for their entire life. Vials are usually given a serial number that, when correlated with a database, allows the full history of the vial to be viewed.
Trials have been carried out using vision systems on tablet inspection to find damage to the outer coating, perform colour measurements and check size and shape.
OCR (optical character recognition) and OCV (optical character
verification) has been carried out on pharmaceutical devices to ensure that
laser printing was correctly set and completed for 18 different languages.
These checks were carried out on-line and did not restrict the production line
speed.
The Data Matrix is a 2D symbol capable of storing a large amount of
information within almost any physical size. It has wide adoption
including the aerospace, automotive
and of course the medical industries.
Unlike barcodes, Data Matrix symbols can be applied directly onto the
product, and or the
Packaging. It can also be read in any orientation and can contain
alphanumeric information
rather than just numbers, removing the need for a ‘look up table’ of
product numbers.
The Instrument Verifier is a presentation reader designed to read 2D
Data Matrix symbols on instruments, or other small items. Surgical instruments
have a value that far exceeds their size, making the ability to individually
track and trace each item highly desirable. With this device organizations can
easily track each item while eliminating manual data entry, thus improving the
speed and accuracy of costs and data collection.
Features:
Integrated lighting and state-of-the-art optics
Read and audible operation makes reading fast and
easy
The incidence of fake, expired, adulterated, mislabelled or
otherwise unauthorized medicinal products reaching the market place is on the
increase. The pharmaceutical industry itself is also at major risk. Today, it
loses sales revenue to counterfeiters and product diverters. If this activity
gets out of control and major tragedies happen, which it can, the resulting
product recalls, brand damage and when stock price falls this will cause major
financial impact at a time when drug company profits are already under extreme
pressure.
Within the pharmaceutical industry the use and application is driven by
Traceability and the fight against counterfeiting. Also the need to record/read
expiry/use by dates at the point of saleor distribution, and where the product
is subject to a quality driven recall program. The Data Matrix is a 2D symbol
capable of storing a large amount of information within almost any physical
size. It has wide adoption including the aerospace, automotive and of course
medical/pharmaceutical industries.
Unlike barcodes, Data Matrix symbols can be applied directly onto the
product, and or the Packaging. It can also be read in any orientation and can
contain alphanumeric information rather than just numbers, removing the need
for a ‘look up table’ of product numbers.
When you source your inline monitoring, verification and control, your
inline readers and your SCADA software from an experienced specialist solution
provider such as MVT, you can be assured of a robust and reliable long term
traceability solution.
The Data Matrix is a 2D symbol capable of storing a large amount of information within almost any physical size.
The Data Matrix is a 2D symbol capable of storing a large amount of
information within almost any physical size.
Benefits
Data
Matrix can carry 25 to 100 times more information than typical bar code:
3116 numeric, 2335 alphanumeric characters or 1556 bytes of binary
information.
6 error
correction schemes to allow recovery from symbol damage.
Round
dots or square cells from almost any type of print device: Inkjet, Etch,
Dot Matrix, Pin Stamp, Thermal Transfer, Pad Print, Laser Print, and Web
Press
Methods of applying the code
Laser –
high speed, high quality permanent marking
Continuous
Inkjet – Non-permanent ink based system ideally suited for high speed
applications
Indent/dot
peen – Permanent ‘impact’ marking on metal and plastic components
Print
and Apply Thermal – Thermal printing systems with automatic inline
applicators
Typical readers
SIMATIC Hawkeye 1525, with dark field illumination for highly reflective parts.
SIMATIC Hawkeye hand-held industrial series for bar and data matrix codes.
SIMATIC VS Series intelligent stand alone cameras.
Reading and Communication – MVRC
MVT/Siemens covers all four key elements with a variety of products, systems, and provides support for the creation of applications.
Marking: Marking a product is normally
done very early on in the production process so that all following steps can be
controlled using the product identity. Marks are often applied to parts with a
method called Direct Part Marking (DPM).
Verification: By
using verification systems, the readability of marks is guaranteed throughout
the entire production process regardless of any possible contamination or when
using different read devices. Also the marking can still be read after the
production process, throughout the life span of the product.
For example, the SIMATIC HawkEye 1500 series provides the capability to monitor
marks in real-time with its DPM verification options. The Measuring code
quality results in cost reductions due to marking cycle time optimization, with
the prevention of plant downtimes and the prevention of additional handling
effort. The Vision Sensor VS130-2 is outfitted with a function that can measure
code quality according to the AIM standard.
Reading: In
order to ensure user friendliness and secure functioning, the readers must
exhibit great flexibility regarding design, interfaces, etc. Only then is it possible
to satisfy the needs of many different industrial sectors. The SIMATIC line of
products, consisting of the compact HawkEye 1500, the Vision Sensor VS130-2
with separate sensor head, and the mobile HawkEye readers, cover all these
requirements.
Communication: The
communication between reading device and process control is performed by a host
of possible standard interfaces, for example by PROFIBUS, PROFINET, Ethernet,
RS232 and by expandable digital inputs and outputs. These interfaces handle the
secure transmission of the trigger signal and also the fast and reliable
transmission of the reading results.
Below is a table of typical 2D code and their features:
Not only can we develop vision applications fast, we use the
industries leading software, built on layers of many years of machine vision
software
For customers needing automated inspection for the factory floor or for
other simple vision tasks without the need for programming, Machine Vision
Technology supply a range of complete vision systems that are simple to install
and set-up. These range from the simplest task oriented ‘Vision Appliances’
through to configurable vision systems capable of more involved vision
applications. These vision systems all have very simple user interfaces that
guide the user through the process of creating an inspection application.
Cognex – PatMax Tool for patterns, matching and sorting
If you are familiar with machine vision, you will know how difficult it can be
to sort different parts, especially when the parts look similar, are touching
or overlapping each other. PatMax can eliminate this confusion by using the
tool to locate and accurately identify each part. Even if the appearances of
the parts vary, reliable sorting is achieved every time and this with a single
accept threshold for all different identified parts.
IPD Vision Appliance- Label alignment, placement and quality. As part of a family of IPD Vision Appliance products, iLabel is an automated ‘Vision Appliance’ that rapidly checks the placement and quality of labels on bottles, boxes, cans and other rigid, packaged goods. The interface screens, which are customized for a label inspection process, enable you to specify areas to inspect, define tolerances for position and rotation, and set thresholds to pass, recycle or fail the label. When these simple steps are done, iLabel uses a proprietary neural net technology to automatically learn what a good label looks like. Once trained, all of these parameters can be saved on the Vision Appliance, or on a network, so that the same inspection solution can be used across multiple manufacturing lines.
These vision systems all have very simple user interfaces that guide the
user through the process of creating an inspection application.
Sherlock
Sherlock is a vision application software development environment that
simplifies the creation and deployment of a wide variety of machine vision
tasks including inspection, packaging, tracking and quality control. Sherlock
is available in two versions to support your individual application needs and
budget.
Sherlock Essential contains the commonly used machine vision features.
Sherlock Professional contains our full suite of machine vision software tools.
There is a huge menu of capabilities to meet your needs:
Pattern recognition
Image analysis
Measurement and gauging
Regions of interest-line, arc, circle, rectangle,
point, and spoke.
