Traceability in Manufacturing – More than just RFID and Barcode

Traceability is a term that is commonly used in most plants today. Whether it is being used to describe tracking received and shipped goods, tracking valuable assets down to their exact location, or tracking an item through production as it is being built, traceability is usually associated with only two technologies — RFID and/or barcode. While these two technologies are critical in establishing a framework for traceability within the plant, there are other technologies that can help tell the rest of the story.

Utilizing vision along with a data collection technology adds another dimension to traceability by providing physical evidence in the form of an image. While vision cameras have been widely used in manufacturing for a long time, most cameras operate outside of the traceability system. The vision system and tracking system often operate independently. While they both end up sending data to the same place, that data must be transported and processed separately which causes a major increase in network traffic.

Datamatrixlesen_Platine

Current vision technology allows images to be “stamped” with the information from the barcode or RFID tag. The image becomes redundant traceability by providing visual proof that everything happened correctly in the build process. In addition, instead of sending image files over the network they are sent through a separate channel to a server that contains all the process data from the tag and has the images associated with it. This frees up the production network and provides visual proof that the finished product is what we wanted it to be.

Used separately, the three technologies mentioned above provide actionable data which allows manufacturers to make important decisions.  Used together, they tell a complete story and provide visual evidence of every step along the way. This allows manufacturers to make more informed decisions based on the whole story not just part of it.

Polarized Retroreflective Sensors: A Solution for Detecting Highly Reflective Objects

The complexity of factory automation creates constant challenges which drive innovation in the industry. One of these challenges involves the ability to accurately detect the presence of shiny or highly reflective objects. This is a common challenge faced in a variety of applications, from sensing wheels in an automotive facility to detecting an aluminum can for filling purposes at a beverage plant. However, thanks to advancements in photoelectric sensing technologies, there is a reliable solution for those type of applications.

Why are highly reflective objects a challenge?

Light reflects from these types of objects in different directions, and with minimum energy loss. This can cause the receiver of a photoelectric sensor to be unable to differentiate between a signal received from the emitter or a signal received from a shiny object. In the case of a diffuse sensor, there is also the possibility that when trying to detect a shiny object, the light will reflect away from the receiver causing the sensor to ignore the target.

So how do we control the direction of the light going back to the receiver, and avoid false triggering from other light sources? The answer is in polarized retroreflective sensors.

Retroreflective sensors require a reflector which reflects the light back to the sensor allowing it to be captured by the receiver. This is achieved by incorporating sets of three mirrors oriented at right angles from each other (referred to as corner cubes). A light beam entering this system is reflected by all three surfaces and exits parallel to the incident beam. Additionally, corner cubes are said to be optically active as they rotate the plane of oscillation of the light by 90 degrees. This concept, along with polarization, allow this type of sensor to accurately detect shiny objects.

Polarization

Light emitted by a regular light source oscillates in planes on dispersal axes. If the light meets a polarizing filter (fine line grid), only the light oscillating parallel to the grid is let through (see figure 1 below).

Figure 1_AR
Figure 1

In polarized retroreflective sensors, a horizontal polarized filter is placed in front of the emitter and a vertical one in front of the receiver. By doing this, the transmitted light oscillates horizontally until it hits the reflector. The corner cubes of the reflector would then rotate the polarization direction by 90 degrees and reflect the light back to the sensor. This way, the returning light can pass through the vertical polarized filter on the receiver as shown below.

Figure 2_AR
Figure 2

With the use of polarization and corner cubed reflectors, retroreflective sensors can create a closed light circuit which ensures that light detected by the receiver was sourced exclusively by the emitter. This creates a great solution for applications where highly reflective targets are influencing the accuracy of sensors or causing them to malfunction. By ensuring proper operation of photoelectric sensors, unplanned downtime can be avoided, and overall process efficiency can be improved.

IO-Link Makes Improving OEE in Format Change Easier than Ever

One of the primary applications in Packaging, Food & Beverage that is a huge area for improving overall equipment efficiency (OEE) is format change.  Buyers respond well to specialized or individualized packaging, meaning manufacturers need to find ways to implement those format changes and machine builders must make those flexible machines available.

IO-Link Makes Improving OEE in Format Change Easier than Ever_2

Today, thanks to IO-Link devices, including master blocks, hubs and linear position sensors, improving OEE on format change is more possible today than ever before. IO-Link offers capabilities that make it ideal for format change. It communicates:

  • Process data (control, cyclical communication of process status)
  • Parameter data (configuration, messaging data with configuration information)
  • Event data (diagnostics, communication from device to master including diagnostics/errors)

What is format change and how does it impact OEE?

Format change is the physical adjustments necessary to make to a machine when the product is altered in some way.  It could be a change in carton size, package size, package design, case size or a number of other modifications to the product or packaging.  The time to adjust the machine itself or the sensors on the machine can take anywhere from 30 minutes to an entire eight- hour shift.

Types of format changes to consider when seeking to improve your OEE:

Guided format change is when the operator is assisted or guided in making the change.  For example, having to move or slide a guide rail into a new position.  IO-Link linear position sensors can help guide the operator, so the position is exact every time. This reduces time by eliminating the need to go back and look at an HMI or cheat sheet to determine if everything is in the right position.

Change parts is when a part needs to be swapped out on the machine for the next production run.  An example of this is when the bag size on a bagger or vertical form fill and seal (VFFS) machine changes and the forming tube needs to be changed.  Having an RFID tag on the forming tube and a RFID reader on the machine allows for easy verification that the correct forming tube was put on the machine and only takes seconds.

Color Change is when the color of a pouch, package or container changes for the next production run like when a yogurt pouch changes color or design while the size and shape remain the same as previous production runs. Smart color photo electric sensors can change the parameters on the photo eye to detect the correct color of the new pouch occurs instantly upon changing the recipe on the machine.

Developing semi-automated or fully automated solutions can improve OEE in regard to format change by helping reduce the time needed to make the change and providing consistent and accurate positioning with the ability to automatically change parameters in the sensor.

Being smart, easy and universal, IO-Link helps simplify format change and provides the ability to change sensor parameters quickly and easily.

IO-Link Makes Improving OEE in Format Change Easier than Ever_1

How TSN boosts efficiency by setting priorities for network bandwidth

As manufacturers move toward Industry 4.0 and the Industrial Internet of Things (IIoT), common communication platforms are needed to achieve the next level of efficiency boost. Using common communication platforms, like Time-Sensitive Networking (TSN), significantly reduces the burden of separate networks for IT and OT without compromising the separate requirements from both areas of the plant/enterprise.

TSN is the mother of all network protocols. It makes it possible to share the network bandwidth wisely by allocating rules of time sensitivity. For example, industrial motion control related communication, safety communication, general automation control communication (I/O), IT software communications, video surveillance communication, or Industrial vision system communication would need to be configured based on their time sensitivity priority so that the network of switches and communication gateways can effectively manage all the traffic without compromising service offerings.

If you are unfamiliar with TSN, you aren’t alone. Manufacturers are currently in the early adopter phase. User groups of all major industrial networking protocols such as ODVA (CIP and EtherNet/IP), PNO (for PROFINET and PROFISAFE), and CLPA (for CC-Link IE) are working toward incorporating TSN abilities in their respective network protocols. CC-Link IE Field has already released some of the products related to CC-Link IE Field TSN.

With TSN implementation, the current set of industrial protocols do not go away. If a machine uses today’s industrial protocols, it can continue to use that. TSN implementation has some gateway modules that would allow communicating the standard protocols while adding TSN to the facility.

While it would be optimal to have one universal protocol of communication across the plant floor, that is an unlikely scenario. Instead, we will continue to see TSN flavors of different protocols as each protocol has its own benefits of things it does the best. TSN allows for this co-existence of protocols on the same network.

 

What to Ask Before You Build an RFID System to Meet Your Traceability Needs

An industrial RFID system is a powerful solution for reliably and comprehensively documenting individual working steps in manufacturing environments. But an industrial RFID system that meets your application needs isn’t available off-the-shelf. To build the system you need, it is important to consider what problems you hope RFID will solve and what return on investments you hope to see.

RFID can deliver many benefits, including process visibility and providing data needed to better manage product quality. It can be used to improve safety, satisfaction and profit margins. It can even be used to help comply with regulatory standards or to manage product recalls. And RFID can be used in a wide range of applications from broad areas like supply management to inventory tracking to more specific applications. These improvements can improve time, cost or performance—though not typically all three.

It is essential to understand and document the goal and how improvements will be measured to in order to plan a RFID system (readers, antennas, tags, cables) to best meet those goals.

Other important questions to consider:

Will the system be centralized or de-centralized? Will the system be license plate only or contain process data on the tag?

How will the data on the tags be used?  Will the information be used to interface with a PLC, database or ERP? Will it be used to provide MES or logical functionality? Or to provide data to an HMI or web browser/cloud interface?

Will the system be required to comply with any international regulations or standards? If so, which ones: EPC Global, Class 1 Gen 2 (UHF only), ISO 15693, or 14443 (HF only)?

What environment does the system need to perform in? Will it be used indoor or outdoor? Will it be exposed to liquids (cleaning fluids, coolants, machine oils, caustics) or high or low temperatures?

Does the RFID system need to work with barcodes or any other human readable information?

What are the performance expectations for the components? What is the read/write range distance from head to tag? What is the station cycle timing? Is the tag metal-mounted? Does the tag need to be reused or be disposable? What communication bus is required?

With a clear set of objectives and goals, the mechanical and physical requirements discovered by answering the questions above, and guidance from an expert, a RFID system can be configured that meets your needs and delivers a strong return on investment.

The Difference Between Intrinsically Safe and Explosion Proof

The difference between a product being ‘explosion proof’ and ‘intrinsically safe’ can be confusing but it is vital to select the proper one for your application.

Both approvals are meant to prevent a potential electrical equipment malfunction from initiating an explosion or ignition through gases that may be present in the surrounding area. This is accomplished in both cases by keeping the potential energy level below what is necessary to start ignition process in an open atmosphere.

What does this mean?

The term “intrinsically safe” describes a protection technique that limits the electrical and/or thermal energy of electrical equipment used in potentially explosive areas such that there is insufficient energy to ignite the hazardous gases or dust.

‘Explosion proof’ applies to an encased apparatus that is capable of withstanding a material explosion. Which means, if combustible gases entered the explosion proof housing and were ignited by the electrical energy within the housing, the resultant “explosion” would be contained inside the housing. The energy from the explosion would then be dissipated through the large surface of flanges or threads paths of the enclosure. By the time the “explosion” exits the housing, there is insufficient energy remaining to ignite the surrounding atmosphere.

How do I know which to choose?

Zone classification is one method for defining the level of risk in a hazardous area and determining which level of protection is required.

Zone 0: Area with permanent risk of explosive atmosphere of air and gas

Zone 1: Area with occasional risk of explosive atmospheres

Zone 2: Area of rare risk of explosive atmospheres of air and gas, only for short periods

Zone 20: Like Zone 0 except atmosphere of air and dust

Zone 21: Like Zone 1 except atmosphere of air and dust

Zone 22: Like Zone 2 except atmosphere of air and dust

Additional certifications and classifications used to determine both explosion proof and intrinsically safe approvals, including more in-depth divisions that explore application and environment specifics, can be found here.

Temperature sensing of process media — a hot topic in today’s manufacturing

Continuous control of process media significantly contributes to the reliability of industrial production. More and more process technology is involved in industrial manufacturing.  Besides pressure and level sensors, temperature sensors are also needed to monitor and control these media. Although new machine designs are often optimized in terms of energy efficiency, heat is added to the production equipment.

Thermal reading of media by temperature sensors

Process stability

To achieve a defined and stable temperature level (in many cases only slightly above the environmental temperature) the added heat dissipation of the production process constantly must be managed. Typically a coolant liquid or hydraulic fluid is cycling through the areas of the production equipment, which tend to heat up. It then runs to a heat exchanger system which cools down the liquid to a defined value. Some applications even require a defined viscosity of the liquids in use. Often the media viscosity depends on its temperature. Historically classic cylindrical housing temperature probes have been applied for temperature measurement. The values are transferred by cables to a PLC. For factory automation applications, housings with integrated display and an adjustable switching point (via pushbutton parametrization) have become more and more popular.

blog2.png

Many housing styles now also include a digital display so in addition to the sensor transmitting temperature values via cable to the control system, they provide a visual monitoring functionality for the machine/plant operator.

blog3
Hydraulic power pack

Monitoring of industrial processes

Monitoring of industrial processes has become more and more relevant. With increasing digitalization in manufacturing, the demand of transparent visualization of the production constantly grows.

 

Power & Force Limiting Cobots for Dull, Dirty and Dangerous Applications

Collaborative robots, or cobots, is currently one of the most exciting topics in automation. But what do people mean when they say “collaborative robot”? Generally, they are talking about robots which can safely work near and together with humans. The goal of a collaborative robot system is to optimize the use of humans and robots, building on the capabilities of each.

There are four modes of robot collaborative operation defined by the global standard ISO/TS 15066. We discussed these modes in a previous blog, Robot Collaborative Operation.

This post will go more deeply into the most commonly used mode: power & force limiting. Robots in this category include ones made by Universal Robots, as well as FANUC’s green robots and ABB’s Yumi.

What is power & force limiting?

Power & force limiting robots are designed with limited power and force, along with physical features to avoid or reduce injury or damage in case of contact. These robots are generally smaller, slower and less powerful than traditional robots but also more flexible and able to work near or with humans — assuming a risk assessment determines it is safe to do so.

The standards define the creation of a shared or collaborative work space for the robot and human, and define how they may interact in this space. In a power & force limiting application, the robot and operator can be in the shared/collaborative work space at the same time and there may be contact or collision between the operator and the collaborative robot system (which includes the robot, gripper/tool and work piece). Under the proper conditions the features built into the power & force limiting robot allow this close interaction and contact to occur without danger to the operator.

What technologies allow these robots to work closely with humans?

The limiting of the robot’s force can be implemented in several ways. Internal torque/feedback sensors in the joints, external sensors or “skins” and/or elastic joints are some of the methods robot suppliers use to assure low force or low impact. They also design possible contact areas to avoid injury or damage by using rounded edges, padding, large surface areas, etc. to soften contact. Grippers, tools and work pieces also need to be considered and designed to avoid injury or damage to people and equipment.

Peripherally, additional sensors in the robots, grippers, tools, work holders and surrounding work stations are critical parts of high performance robot applications. Connecting these sensors through protocols such as IO-Link and PROFISafe Over IO-Link allows more tightly integrated, better performing, and safer collaborative robot systems.

Where are power & force limiting robots typically applied?

Similar to traditional robots, power & force limiting robots are best applied in applications which are dull, dirty and/or dangerous (the 3 Ds of robotics). They are especially well suited to applications where the danger is ergonomic — repetitive tasks which cause strain on an operator. In many cases, power & force limiting robots are being applied to cooperate closely with people: the robots take on the repetitive tasks, while the humans take on the tasks which require more cognitive skills.

A large number of the customers for power & force limiting robots are small or medium-sized enterprises which can not afford the investment and time to implement a traditional robot, but find that power & force limiting robots fit within their budget and technical capabilities.

What are some of the benefits and drawbacks to power & force limiting robots?

Benefits:

  • Low cost
  • Fast, simple programming and set up; often does not require special knowledge or training
  • Small and lightweight
  • Easy to deploy and redeploy
  • Can be fenceless
  • Low power usage
  • Close human-robot interaction

Drawbacks:

  • Slow
  • Small payload
  • Low force
  • Low precision (not always the case, and improving)

Final Thoughts

Buying a power & force limiting robot does not necessarily mean that fences or other safeguards can be removed; a risk assessment must be completed in order to ensure the application is appropriately safeguarded. The benefits, however, can be significant, especially for smaller firms with limited resources. These firms will find that power & force limiting robots are very good at cost-effectively solving many of their dull, dirty and dangerous applications.

Zone Defense: How to Determine If You Need a Hygienic or Washdown Solution

It goes without saying that food safety is an extremely important aspect of the food and beverage industry. While manufacturers would naturally take precautions to ensure their food products are safe to consume, they are required to follow a set of rigid guidelines and standards to ensure the safety of the foodstuffs to prevent contamination.

CaptureTo determine which rating, standards or certifications are required for a particular food and beverage segment, you must first consider the type of food contact zone and whether it is an open or closed process.

Food Contact Zones

The food contact zone is determined by the potential contamination that can occur based on the production equipment’s exposure to food and its byproducts.

  • Food Zone: an area intended to be exposed to direct contact with food or surfaces where food or other substances may contact and then flow, drain or drain back onto food or food contact surfaces.
  • Splash Zone: an area that is routinely exposed to indirect food contact due to splashes and spills. These areas are not intended for contact with consumable food.
  • Nonfood Zone: An area that is not exposed to food or splashes but will likely be exposed to minor dirt and debris.

Open and Closed Production

In the food and beverage industry, it is also important to discuss whether the manufacturing process is open or closed. The distinction between the two plays a significant role in determining machine cleaning requirements.

  • Closed Process: A manufacturing operation in which the food product never comes in contact with the environment. All food contact zones are sealed such as the inner surfaces of tanks, pipelines, valves, pumps and sensors.
  • Open Process: A manufacturing operation in which food does have contact with the environment outside of the machine. This requires a hygienic design of the process environment, as well as the surfaces of the apparatus and components.

Required ratings, standards and certifications

Once you know the food zone and whether the production is open or closed, it becomes simple to determine which ratings, standards or certifications are required of the machinery and apparatus in the food and beverage manufacturing process.

  • Food Contact Zone — Hygienic
    • IP69K – tested to be protected from high pressure steam cleaning per DIN40050 part 9
    • FDA – made of FDA approved materials, most often 316L stainless steel
    • 3-A – certified sanitary and hygienic equipment materials and design in the US
    • EHEDG – certified sanitary and hygienic equipment materials and design in Europe
  • Food Splash Zone — Washdown
    • IP69K – tested to be protected from high pressure steam cleaning per DIN40050 part 9
    • ECOLAB – surfaces tested to be protected from cleaning and disinfecting agents
  • Nonfood Zone — Factory Automation
    • IP67 – rated for water immersion up to a meter deep for half an hour
    • IP65 – rated as dust tight and protected against water projected from a nozzle

For more information on the requirements of the food and beverage industry, visit www.balluff.com.

IO-Link devices deliver data specific to your manufacturing operations needs

IO-Link is a point-to-point communication standard [IEC61131-9]. It is basically a protocol for communicating information from end devices to the controller and back. The beauty of this protocol is that it does not require any specialized cabling. It uses the standard 3-pin sensor cable to communicate. Before IO-Link, each device needed a different cable and communication protocol. For example, measurement devices needed analog signals for communication and shielded cables; digital devices such as proximity sensors or photo eyes needed 2-pin/3-pin cables to communicate ON/OFF state; and any type of smart devices such as laser sensors needed both interfaces requiring multi-conductor cables. All of these requirements and communication was limited to signals.

Shishir1

With IO-Link all the devices communicate over a standard 3-pin (some devices would require 4/5 pin depending if they need separate power for actuation). And, instead of communicating signals, all these devices are communicating data. This provides a tremendous amount of flexibility in designing the controls architectures for the next generation machines.

IO-Link data communication can be divided into 3 parts:

  1. Process data: This is the basic functionality of the sensor communicated over cyclical messages. For example, a measurement device communicating measurement values, not 4-20mA signals, but the engineering units of measurement.
  2. Parameter data: This is a cyclic messaging data communication and where IO-Link really shines. Manufacturers can add significant value to their sensors in this area. Parameter data is communicated only when the controller wants to make changes to the sensor. Examples of this include changing the engineering units of measurement from inches to millimeters or feet, or changing the operational mode of a photoelectric sensor from through-beam to retro-reflective, or even collecting capacitance value from a capacitive sensor. There is no specific parameter data governed by the consortium — consortium only focuses on how this data is communicated.
  3. Event data: This is where IO-Link helps out by troubleshooting and debugging issues. Event messages are generated by the sensor to inform the controller that something has changed or to convey critical information about the sensor itself. A good example would be when a photoeye lens gets cloudy or knocked out of alignment causing a significant decrease in the re-emitted light value and the sensor triggers an event indicating the probable failure. The other example is the sensor triggering an event to alert the control system of a high amperage spike or critical ambient temperatures. When to trigger these events can be scheduled through parameter data for that sensor.

Shishir2

Each and every IO-Link device on the market offers different configurations and are ideally suited for various purposes in the plant. If inventory optimization is the goal of the plant, the buyer should look for features in the IO-Link device that can function in different modes of operation such as a photo eye that can operate as through-beam or retro-reflective. On the other hand, if machine condition monitoring is the objective, then he should opt for sensors that can offer vibration and ambient temperature information along with the primary function.

In short, IO-Link communication offers tremendous benefits to operations. With options like auto-parameterization and cable standardization, IO-Link is a maintenance-friendly standard delivering major benefits across manufacturing.

Shishir3