Vision Systems for Robot Guidance

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.

Vision systems in the Printing Industry

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 Vision Systems

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.

Electronic Vision Systems

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.

Automotive Vision Systems

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.

Food and Packing Vision Systems

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.

Pharmaceutical – 21 CFR part 11

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.

Surgical Instrument Track and Trace 2D Matrix Code Reader/ Verifier

DMC Verification types:

  • ISO –IEC6022;2000 AIM Specification
  • ISO – IEC15415
  • AS9132 RevA;2000BC Licence ANSI

September 2009 onwards:

  • AIM DPM-1-2006 DMC Licence

Track and Trace-as driven by GS1

  • Supplier/Distributor to NHS stock
  • Stores to theatre
  • Usage and sterilisation records

The Data Matrix

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.


  • Integrated lighting and state-of-the-art optics
  • Read and audible operation makes reading fast and easy
  • Manufactured in SS to IP65
  • Fiducial area for code positioning
  • Fixed standoff
  • Verification TCP/IP output available

Pharmaceutical 2D Bar Coding

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.


  • 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:

Software Systems

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 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.
  • In line scripting and landmark
  • Image recording and Playback
  • And others