IO-Link Wireless – IO-Link with Even Greater Flexibility

In a previous blog entry, I discussed IO-Link SPE (Single-Pair Ethernet). SPE, in my opinion, has two great strengths compared to standard IO-Link: cable length and speed. With cable lengths of up to 100 meters and speed of 10 Mbps, compared to 20 meters and max baud rate of 230.4 Kbps, what could be out of reach?

Robots. We see robots with cabling routed either through the arm itself or tracking along the outside of the arm. Every time the robot moves, we know the conductors within these cables are deteriorating. Is there another “tool” in the IO-Link Consortiums special interest groups that can aid us? Yes, IO-Link Wireless.

Basics

Let cover the basics quickly. The architecture will contain a wireless master, wireless in terms of the connection to the IO-Link devices and wireless IO-Link devices. There is no real change to the physical connection of the IO-Link master to the controls system, just the elimination of cabling between the IO-Link master and IO-Link devices. It is perfect for a robot application.

Power

Wireless concepts are not new. When I saw the specification to IO-Link Wireless, the first question that came to mind was about powering the IO-Link devices. Luckily, we are in an age of batteries. and with the evolution of the EV market, battery technology has come a long way. This eliminates my concerns for low power devices. IO-Link was designed to bring more data back from our sensor and actuator devices, so IO-Link is perfectly suited to pass along battery diagnostics; low or failing batteries diagnostics/information should be readily available for a control and/or IIOT system. IO-Link devices with high current consumptions will still need to be wired to a power system.

Density of IO-Link Devices per IO-Link Master

Currently, with wired IO-Link masters, the most common configuration is eight IO-Link ports (i.e., 8 IO-Link devices can be connected), with the rare 16 port version. There is a huge advantage to wireless here within the IO-Link specification. One wireless IO-Link Master can contain up to 5 transmission tracks, where each transmission track can communicate to up to 8 IO-Link devices. That is 40 wireless IO-Link devices per wireless IO-Link master. There are a lot of details within the IO-Link Wireless specification that I will not even begin to discuss, but to go one layer more; within a physical area that the specification calls a “cell”, three wireless IO-Link Masters can exist, giving us a total of 120 wireless IO-Link devices occupying a designated area. We all know that wireless will come with a larger price tags, but at least there is a tradeoff of fewer masters (wired = 15 master, wireless = 3, for 120 devices).

Distance and Speed

I started this blog entry referencing the two strengths of SPE — length and speed. Here is where there is a great difference between Wireless and SPE IO-Link exists. If a wireless master is using one transmission track, the 8 IO-Link devices can be 20 meters away, equaling the standard wired architecture of IO-Link. As soon as we enable another transmission track, the maximum distance drops to 10 meters. The minimum transmission cycle time is 5 milliseconds. Still, I believe the pros of IO-Link Wireless outweigh the length restrictions.

Non-wireless IO-Link devices

Within the specification, there is the ability to have wireless bridges in the architecture. These bridge modules would contain a master IO-Link port to communicate to the standard IO-Link device, and then on the other side communicate to the wireless IO-Link master as a IO-Link Wireless device.

Applications

Obviously, robot end-efforts are the first to come to mind for a wireless solution. Food, beverage and medical applications also comes to mind. By eliminating the cabling, there is less surface area where contaminants can exist. Also, it could be used in inductive race ways, where a “pallet” moves along an inductive rail, which is supplying power, but I may not want to put a controller on each pallet. Lastly, IO-Link Wireless could be a good solution in any place where cabling is flexed and bent.

Conclusion

Does standard wired IO-Link fit every application? No. Does Single-Pair Ethernet and IO-Link Wireless? No. Thankfully, the IO-Link Consortium is giving us multiple methodologies to create our IO-Link architectures, where one application may need to encompass all three. For those applications that require fewer or the elimination of cables, the IO-Link Wireless solution can fit this space. For further information on the IO-Link specification, go to the consortium’s website at: IO-Link.com.

Factor 1 sensors make auto production more flexible

Have you ever climbed a mountain with a backpack? Then you understand that the lower the load, the less power is needed and the lower the energy consumption. The same is true for cars. And in regard to electric vehicles, this is even more important: The more weight that can be saved somewhere else, the larger the battery can be, thus increasing the range of the electric car.

Lightweight construction is key for weight reduction. By using a sensible mix of materials, weight can be saved without compromising functionality and safety or drastically increasing costs. High-strength steels or light metals are used for body parts or seat frames. However, this mix of materials has an impact on automotive production when it comes to selecting the sensor technology. Inductive sensors have become an indispensable part of automotive construction; however, they react to different metals. This would mean frequent adjustments during production. Fortunately, we have Factor 1 sensors.

Inductive sensors react to metals. Their task is to detect metal objects without contact. The distance at which the corresponding object can be detected by the respective sensor is called the switching distance. The switching distance for standard inductive sensors depends on the material of the metal. Steel, for example, is detected much better than aluminum or copper. The switching distance can be reduced by up to 70% for non-ferromagnetic materials.

 

To eliminate this problem, Factor 1 sensors were developed. They offer all of the advantages of inductive sensors with the added bonus of having the same switching distance for all metals. This makes them ideally suited for the detection of changing objects (steel, aluminum, brass, copper etc.) and a perfect fit for the production of electric cars or anywhere different types of metals need to be used and identified. And because Factor 1 sensors are magnetic-field resistant, they can be used in areas  with strong electromagnetic fields, such as welding plants.

For more information, visit https://www.balluff.com/local/us/products/product-overview/sensors/inductive-sensors/#/inductive-factor-1-sensors

Continuous and Exacting Measurements Deliver New Levels of Quality Control

Quality control has always been a challenge. Going back centuries, the human eye was the only form of quality verification. Hundreds of years ago metal tools like calipers were introduced to allow for higher repeatability compared to the human eye. This method is very cumbersome and is only an approximation based off a sample of the production, potentially allowing faulty products to be used or shipped to the customer.

What is the best solution by today’s standards? By scanning the product at all times! Using continuous measurements reduces or even eliminates the production of faulty products and allows for consistent and repeatable production. This used to be an impossible task for small products, but with the invention of the laser and CMOS(Complementary Metal Oxide Semiconductor) imaging sensors, extremely small measurements can be achieved. How small? In an industrial environment, measuring 0.3 mm components with a resolution of 10 micrometers is absolutely attainable. Using special optics to spread the beam across a window will allow for 105 mm of measuring range and up to 2 meters distance between the transmitter (laser spread light) and receiver (CMOS sensor).

Traditionally these sensor systems have one or two analog outputs and have to be scaled in the control system to be usable. These values are repeatable and accurate once scaled but there has to be a better way. IO-Link to the rescue!

IO-Link brings an enormous amount of information and flexibility to configuration. Using IO-Link will also reduce the amount of wiring and analog input cards/hubs required. The serial communications of IO-Link also reduce overall costs thanks to its use of standard cables, as opposed to shielded cables. This allows for 20 meter runs over a standard double ended M12 cables without information loss or noise injection. Another benefit to going with IO-Link is the drastic increase in bits of resolution. Analog input cards and analog input hubs tend to provide between 10-16 bits of resolution, whereas IO-Link has the ability to pass two measurements via process data in the form of dual 32 bit resolution arrays as well as more information about the status of the sensors.

With IO-Link, you also gain the ability to use system commands like restarting the device, factory reset, signal normalization, reset maintenance interval, and device discovery. With this level of technology and resolution, quality control can be taken to down to the finest details.

Robust Cylinder Feedback Adds Safety to Mobile Equipment Applications

Adding position feedback to a hydraulic cylinder provides several benefits which include increasing the efficiency of a process, automating a function, and adding safety to a machine. Most manufacturers of cylinder sensing products offer both discrete and proportional outputs to achieve the cylinder feedback required of the application. Of the proportional types, there’s been a few technologies utilized through the years which include resistive potentiometers, glass scales, linear Hall effect, optical readers, linear variable displacement transducers (LVDT’s), and magnetostrictive transducers. Of these many technologies, magnetostriction continues to be the technology of choice for many absolute position feedback applications due to its non-contact sensing, repeat accuracies, linearities within a few micrometers, and robust mechanical assemblies.

The phenomenon of magnetostriction was first discovered by James Joule in 1842. Joule found that a ferromagnetic material, such as an iron rod, would change dimensions slightly when subjected to a magnetic field. Today’s magnetostrictive transducers use special ferromagnetic alloys and utilize Joule’s effect as a position marker. Additional electronics, including time-of-flight circuitry, are then used to define the position and/or velocity of the marker. While the technology of the magnetostrictive transducer is sophisticated today, the general principal remains the same and is well proven.

Magnetostrictive transducers are widely used in steel mills, sawmills, tire manufacturers and many other industrial processes. They are also widely used in mobile equipment in industries such as construction, agriculture, and rail maintenance of way vehicles.

One strong application for cylinder feedback in mobile equipment is for operator safety. Large mobile elevated work platforms (MEWPs, aka boom lifts, man lifts, cherry pickers, etc.) do not utilize outriggers to stabilize the machine due to the machine’s ability to drive while the basket (and operator) are at height. These machines are also likely to be rented, leaving the skill of the operator in question. A quality cylinder transducer provides precise position feedback to the electronic control module which determines if the operator is approaching an unsafe working condition. One such scenario is when the boom is at 45 degrees and telescoping further out from the side of the machine. In this case, the joystick controls will limit the operator inputs to keep the machine from extending any further out, keeping the machine within a predetermined working “envelope.” Another popular application would be as a memory function. A good magnetostrictive transducer will allow the operator to “teach” a specific position. The operator can return to the programmed position automatically. Memory functions are useful for repeat actions such as returning a bucket to a specific height. If trucks to be filled are all the same height, the memory function can save time and reduce mishaps, allowing the operator to concentrate on other functions such as turning and driving. In the rail industry, maintenance of way machines uses magnetostrictive transducers to determine the depth of hydraulic tines that are used to compact ballast, or to raise the track to a specific height.

No matter what the application, when reliable feedback of a cylinder is needed, magnetostrictive transducers provide reassuring feedback on mobile machines, even in harsh conditions.

But not all magnetostrictive transducers are found within a cylinder housing. Some manufacturers offer both internal and external products. The arguments for an internal approach center around added protection for the transducer from rocks, dirt, heat, etc., while advocates for an external approach speak of less downtime in the event of a transducer mishap, and the reduced costs and delivery times of using a standard cylinder. A reputable manufacturer with technical experts can help guide your choice.

Whether internal or external, industrial or mobile, the phenomenon of magnetostriction will continue to be the technology chosen for reliable, accurate detection of hydraulic cylinders.

Getting Condition Data From The Shop Floor to Your Software

IIoT (Industrial Internet of Things)  is becoming more mainstream, leading to more vendors implementing innovative monitoring capabilities in the new generation of sensors. These sensors are now multifunctional and provide a host of additional features such as self-monitoring.

With these intelligent sensors, it is possible to set up a system that enables continuous monitoring of the machines and production line. However, the essential requirement to use the provided data for analysis and condition monitoring for preventative and predictive maintenance is to get it from the shop floor to the MES, ERP, or other analysis software suites.

There are a variety of ways this can be done. In this post we will look at a few popular ways and methods to do so.

The most popular and straightforward implementation is using a REST API(also known as RESTful API). This has been the de facto standard in e consumer space to transport data. It allows multiple data formats to be transferred, including multimedia and JSON (Javascript Object Notation)

This has certain disadvantages like actively polling for the data, making it unsuitable for a spotty network, and having high packet loss.

MQTT(Message Queuing Telemetry Transport) eliminates the above problem. It’s very low bandwidth and works excellent on unreliable networks as it works on a publish/subscribe model. This allows the receiver to passively listen for the data from the broker. The broker only notifies when there is a change and can be configured to have a Quality of Service(QoS) to resend data if one of them loses connection. This has been used in the IoT world for a long time has become a standard for data transport, so most of software suits have this feature inbuilt.

The third option is to use OPCUA, which is the standard for M2M communication. OPCUA provides additional functionality over MQTT as it was developed with machine communication in mind. Notably, inbuilt encryption allows for secure and authenticated communication.

In summary, below is a comparison of these protocols.

A more detailed explanation can be found for these standards :

REST API : https://www.redhat.com/en/topics/api/what-is-a-rest-api

MQTT : https://mqtt.org/

OPCUA : https://opcfoundation.org/about/opc-technologies/opc-ua/

Photoelectric Sensors in the Packaging, Food, and Beverage Industry

The PFB industry requires the highest standards of quality and productivity when it comes to both their products and their equipment. In order to keep up with the rising demands to produce high quality parts quickly, many in the industry have incorporated photoelectric sensors into their lines. With their durable designs, accurate measurements and fast data output speeds, it is easy to see why. Combine the sensors’ benefits with the clean and well-lit environment of a PFB plant, and it begins to feel like this product was made specifically for the industry. There are many variants of photoelectric sensors, but the main categories are: through beam, diffuse, and retro-reflective sensors.

Through Beam

Through beam sensors come in many different shapes and sizes but the core idea stays the same. An emitter shoots LED red, red laser, infrared, or LED infrared light across an open area toward a receiver. If the receiver detects the light, the sensor determines nothing is present. If the light is not detected, this means an object has obstructed the light.

Applications:

  • Object detection during production
  • Detecting liquid in transparent bottles
  • Detecting, counting, and packaging tablets

Diffuse Beam

Diffuse beam sensors operate a little differently in that the emitter and receiver are in the same housing, often very closely to one another. With this sensor, the light beam is emitted out, the light bounces off a surface, and the light returns to the receiver. The major takeaway with the diffuse beam sensor is that the object being detected is also being used as the reflecting surface.

Applications:

  • Label detection
  • Monitoring the diameter of film
  • Verifying stack height on pallet

Retro-Reflective Beam

Retro-reflective sensors are similar to diffuse beam sensors in that the emitter and receiver are also contained within the same housing. But this sensor requires an additional component — a reflector. This sensor doesn’t use the object itself to reflect the light but instead uses a specified reflector that polarizes the light, eliminating the potential for false positive readings. Retro-reflective sensors are a strong alternative to through beam when there isn’t room for two separate sensor heads.

Applications:

  • Transparent film detection
  • Detection of shrink-wrapped pallets
  • Detecting any reflective target

RFID Replaces Bar Codes for Efficient Asset Tracking

Bar code technology has been around for many years and is a tried and true means for tracking asset and product movement, but it has its limitations. For example, a bar code reader must have an unobstructed view of the bar code to effectively scan. And the bar code label cannot be damaged, or it is then unreadable by the scanner.

In more recent years, additional RFID technologies have been more readily available for use to accomplish the same task but with fewer limitations. Using RFD, a scanner may be able to read tags that are blocked by other things and not visible to the naked eye. UHF RFID can scan multiple tags at the same time in a single scan, whereas most bar codes need to be scanned individually. This, therefore, increases efficiency and reduces the time required to perform the scans.

Then, of course, there is the human factor. RFID can help eliminate mistakes caused by human error. Most bar code scanning is done with hand scanners held by workers since the scanner has to be in the exact position to see the bar code to get a good scan. While manual/hand-held scanning can be done using RFID, most times a fixed scanner can be used as long as the position of the RFID tag can be guaranteed within certain tolerances. These tolerances are much greater than with a bar code scanner.

With the advent of inexpensive consumable RFID labels, the ease and cost of transitioning to RFID technology has become more feasible for manufacturers and end users. These labels can be purchased for pennies each in rolls of several thousand at a time.

It should be noted that several companies now produce printers that can actually code the information on a RFID label tag while also printing data, including bar codes, on these label tags so you have the best of both worlds. Tags can be scanned automatically and data that can be read by the human eye as well as a bar code scanner.

Some companies have expressed concern about the usage of RFID in different countries due to local regulations regarding the frequencies of radio waves causing interferences.

This is not an issue for HF  and UHF technology. HF is an ISO standard (ISO 15693) technology so it applies to most everywhere. For UHF, which is more likely to be used due to the ability to scan at a distance and scan multiple tags at the same time, the only caveat is that different areas of the world allow scanners to only operate in certain frequencies. This is overcome by the fact that almost all UHF tags that I have encountered are what are called global tags.

This means these tags can be used in any of the global frequency ranges of UHF signals. For example, in the North America, the FCC restricts the frequency range for UHF RFID scanners to 902-928 MHz, whereas MIC in Japan restricts them to 952-954 MHz, ETSI EN 300-220 in Europe restricts them to 865-868 MHz, and DOT in India restricts them to 865-867 MHz. These global tags can be used in any of these ranges as they work from 860 to 960 MHz.

On the subject of UHF, it should be mentioned that in addition to the frequency ranges restricted by various part of the world, maximum antenna power is also locally restricted.

For more information on RFID for asset tracking, visit https://www.balluff.com/local/us/products/product-overview/rfid/

 

Ensure Food Safety with Machine Vision

Government agencies have put food manufacturers under a microscope to ensure they follow food safety standards and comply with regulations. When it comes to the health and safety of consumers, quality assurance is a top priority, but despite this, according to The World of Health Organization, approximately 600 million people become ill each year after eating contaminated food, and 420,000 die.

Using human manual inspection for quality assurance checks in this industry can be detrimental to the company and its consumers due to human error, fatigue and subjective opinions. Furthermore, foreign particles that should not be found in the product may be microscopic and invisible to the human eye. These defects can lead to illness, recalls, lawsuits, and a long-term negative perception of the brand itself. Packaging, food and beverage manufacturers must realize these potential risks and review the benefits of incorporating machine vision. Although machine vision implementation may sound like a costly investment, it is small price to pay when compared to the potential damage of uncaught issues. Below I explore a few benefits that machine vision offers in the packaging, food and beverage industries.

Safety
Consumers expect and rely on safe products from food manufacturers. Machine vision can see through packaging to determine the presence of foreign particles that should not be present, ensuring these products are removed from the production line. Machine vision is also capable of inspecting for cross-contamination, color correctness, ripeness, and even spoilage. For example, bruises on apples can be hard to spot for the untrained eye unless extremely pronounced. SWIR (shortwave infrared) illumination proves effective for the detection of defects and contamination. Subsurface bruising defects become much easier to detect due to the optimization of lighting and these defected products can be scrapped.

Uniformity of Containers
Brand recognition is huge for manufacturers in this industry. Products that have defects such as dents or uneven contents inside the container can greatly affect the public’s perception of the product and/or company. Machine vision can detect even the slightest deformity in the container and ensure they are removed from the line. It can also scan the inside of the container to ensure that the product is uniform for each batch. Vision systems have the ability optimize lighting intensity, uniformity, and geometry to obtain images with good contrast and signal to noise. Having the ability to alter lighting provides a much clearer image of the point of interest. This can allow you to see inside a container to determine if the fill level is correct for the specific product.

Packaging
Packaging is important because if the products shipped to the store are regularly defected, the store can choose to stop stocking that item, costing the manufacturer valuable business. The seal must last from production to arrival at the store to ensure that the product maintains its safe usability through its marked expiration date. In bottling applications, the conveyors are moving at high speeds so the inspection process must be able to quickly and correctly identify defects. A facility in Marseille, France was looking to inspect Heineken beer bottles as they passed through a bottling machine at a rate of 22 bottles/second (80,000 bottles/hour). Although this is on the faster end of the spectrum, many applications require high-speed quality checks that are impossible for a human operator. A machine vision system can be configured to handle these high-speed applications and taught to detect the specified defect.

Labels

It’s crucial for the labels to be printed correctly and placed on the correct product because of the food allergy threats that some consumers experience. Machine vision can also benefit this aspect of the production process as cameras can be taught to recognize the correct label and brand guidelines. Typically, these production lines move at speeds too fast for human inspection. An intuitive, easy to use, machine vision software package allows you to filter the labels, find the object using reference points and validate the text quickly and accurately.

These areas of the assembly process throughout packaging, food and beverage facilities should be considered for machine vision applications. Understanding what problems occur and the cost associated with them is helpful in justifying whether machine vision is right for you.

For more information on machine vision, visit https://www.balluff.com/local/us/products/product-overview/machine-vision-and-optical-identification/.

 

 

Turning Big Data into Actionable Data

While RFID technology has been available for almost seventy years, the last decade has seen widespread acceptance, specifically in automated manufacturing. Deployed for common applications like automatic data transfer in machining operations, quality control in production, logistics traceability and inventory control, RFID has played a major role in the evolution of data collection and handling. With this evolution has come massive amounts of data that can ultimately hold the key to process improvement, quality assurance and regulatory compliance. However, the challenge many organizations face today is how to turn all that data into actionable data.

Prominent industry buzzwords like Industry 4.0 and the Industrial Internet of Things (IIOT) once seemed like distant concepts conjured up by a marketing team far away from the actual plant floor, but those buzzwords are the result of manufacturing organizations around the globe identifying the need for better visibility into their operations. Automation hardware and the infrastructure that supports it has advanced rapidly due to this request, but software that turns raw data into actionable data is still very much in demand. This software needs to provide interactive feedback in the form of reporting, dashboards, and real time indicators.

The response to the demand will bring vendors from other industries and start-ups, while a handful of familiar players in automation will step up to the challenge. Competition keeps us all on our toes, but the key to filling the software gap in the plant is partnering with a vendor who understands the needs on the plant floor. So, how do you separate the pretenders from the contenders? I compiled a check list to help.

Does the prospective vendor have:

  • A firm understanding that down time and scrap need to be reduced or eliminated?
  • A core competency in automation for the plant floor?
  • Smart hardware devices like RFID and condition monitoring sensors?
  • A system solution that can collect, analyze, and transport data from the device to the cloud?
  • A user-friendly interface that allows interaction with mobile devices like tablets and phones?
  • The capability to provide customized reports to meet the needs of your organization?
  • A great industry reputation for quality and dependability?
  • A chain of support for pre-sales, installation, and post-sales support?
  • Examples of successful system deployments?
  • The willingness to develop or modify current devices to address your specific needs?

If you can check the box for all of these, it is a safe bet you are in good hands. Otherwise, you’re rolling the dice.

Document Product Quality and Eliminate Disputes with Machine Vision

“I caught a record-breaking walleye last weekend,” an excited Joe announced to his colleagues after returning from his annual fishing excursion to Canada.

“Record-breaking?  Really?  Prove it.” demanded his doubtful co-worker.

Well, I left my cell phone in the cabin so it wouldn’t get wet on the boat so I couldn’t take a picture, but I swear that big guy was the main course for dinner.”

“Okay, sure it was Joe.”

We have all been there — spotted a mountain lion, witnessed an amazing random human interaction, or maybe caught a glimpse at a shooting star.  These are great stories, but they are so much more believable and memorable with a picture or video to back them up.  Now a days, we all carry a camera within arm’s reach.  Capturing life events has never been easier and more common, so why not use cameras to document and record important events and stages within your manufacturing process?

As the smart phone becomes more advanced and common, so does the technology and hardware for industrial cameras (i.e. machine vision).  Machine vision can do so much more than pass fail and measurement type applications.  Taking, storing, and relaying pictures along different stages of a production process could not only set you apart from the competition but also save you costly quality disputes after it leaves your facility.  A picture can tell a thousand words, so what do you want to tell the world?  Here are just a couple examples how you can back up you brand with machine vision:

Package integrity: We have all seen the reduced rack at a grocery store where a can is dented or missing a label.  If this was caused by a large-scale label application defect, someone is losing business.  So, before everyone starts pointing fingers, the manufacturer could simply provide a saved image from their end-of line-vision system to prove the cans were labeled when shipped from their facility.

Assembly defects: When you are producing assembled parts for a larger manufacturer, the standards they set are what you live and die by.  If there is ever a dispute, having several saved images from either individual parts or an audit of them throughout the day could prove your final product met their specifications and could save your contract.

Barcode legibility and placement: Show your retail partners that your product’s bar code will not frustrate the cashier by having to overcome a poorly printed or placed barcode.  Share images with them to show an industrial camera easily reading the code along the packaging line ensuring a hassle-free checkout as well as a barcode grade to ensure their barcode requirements are being met.

In closing, pictures always help tell a story and make it more credible.  Ideally your customers will take your word for it, but when you catch the record-breaking walleye, you want to prove it.