Collaborative Automation…It’s Not Just for Robots

Manufacturing is made up of hundreds of discrete operations. Some are repetitive, while others are more diverse. Repetitive tasks are ideal for automation while diverse tasks require more flexibility. And while automation can be extremely flexible, that comes with a high initial investment costs and significant deployment time. The alternative? People!

Humans have the unrivaled ability to adapt to a diverse and flexible manufacturing environment. They can be productive relatively quickly with proper guidance without high initial cost investments.

But as we all know, “to err is human” and this is one of the biggest issues with manual operations. People need a little guidance from time to time. Collaboration is not just for robots; It’s for complete automation systems as well.

Collaborative automation is most important at the point-of-use, where humans are performing critical operations. Some of those common operations include:

  • Manual assembly for low volume or highly flexible operations
  • Delivery of raw materials to the point-of-use
  • Kit assembly for down-stream operation
  • Machine setup and change-over
  • Machine maintenance and calibration

All of these functions can be done error-free and with little training by simply guiding people within their current work envelope, also referred to as their point-of-use. This type of a lean function provides hands-free guidance in the form of indication devices connected directly to your automation system allowing workers to stay focused on the task at hand instead of looking elsewhere for instructions.

With the technology of IO-Link, smart indication devices can now show much more information to all the people involved in specific manufacturing tasks. Automation has an immediate and direct connection to the people that are so vital.

For example, in a manually-fed weld-cell, the smart indicators are capable of not only signaling that the part is loaded correctly, but also whether the part is out of alignment (shown here by the red indicator) or that something wrong with one of the automation components such as a stuck pneumatic clamp.

Figure 1
A manually-fed weld-cell with smart indicators is capable of not only signaling that the part is loaded correctly, but also if the part is out of alignment (shown by the red indicator) or that there is something wrong with one of the automation components such as a stuck pneumatic clamp.

Even better, with IIoT technology, trends can be analyzed to determine if the fixture/tool could be optimized for production or to identify common failure points. This all leads to tighter collaboration with operations, maintenance personnel and production supervisors.

A traditional kitting station, sometimes referred to as a supermarket, is another ideal application for smart indicators. Not only can they guide a single operator to the intended part to pull, they can guide multiple operators at the same time.  Also, smart indicators can inform of incorrect pulls, potential bin options (a physically closure bin), directional information, and inventory levels. And again, with IIoT technology, trends can be analyzed to determine proper layout, individual personnel performance and system throughput. The automation system collaborates with operations, forklift drivers and production supervisors.

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A traditional kitting station, sometimes referred to as a supermarket, with smart indicators to guide operators to the intended part to pull.

So, take a look and see what a collaborative automation system utilizing smart indicators can do for your manual operations. You might be surprised.

Top 5 Insights from 2018

With the start of the new year, let’s take a look at the top 5 insights from 2018.

1. An Easy Way to Remember PNP and NPN Sensor Wiring

“Switched” refers to which side of the controlled load (relay, small indicator, PLC input) is being switched electrically. Either the load is connected to Negative and the Positive is switched (PNP), or the load is connected to Positive and the Negative is switched (NPN). These diagrams illustrate the differences between the two connections…READ MORE

2. Back to the Basics: What is the Value of IO-Link?

With the demands for flexible manufacturing, efficient production & visibility in our factories, smart manufacturing is driving the way we work today.  Analytics and diagnostics are becoming critical to our ability to perform predictive maintenance, improve equipment effectiveness and monitor the condition of the machine as well as the components inside the machine.  Typically, our first reaction is to put these devices onto Ethernet.  However, the implementation of Ethernet requires a high skill set that is scarce in our traditional manufacturers today.  Due to the simple control architecture of IO-Link devices, it allows for many Smart devices to provide the data we need for analytics with a reduction in the Ethernet skill set that has become a roadblock for many manufacturers…READ MORE

3. What Exactly is Safety Over IO-Link?

Users of IO-Link have long been in search of a solution for implementing the demands for functional safety using IO-Link. As a first step, the only possibility was to turn the actuators off using a separate power supply (Port class “B”, Pins 2, 5), which powers down the entire module. Today there is a better answer: Safety hub with IO-Link!…READ MORE

4. Safety Over IO-Link Helps Enable Human-Robot Collaboration

Safety Over IO-Link makes it easier to align a robot’s restricted and safeguarded spaces, simplifies creation of more dynamic safety zones and allows creation of “layers” of sensors around a robot work area.

For the past several years, “collaboration” has been a hot topic in robotics.  The idea is that humans and robots can work closely together, in a safe and productive manner.  Changes in technology and standards have created the environment for this close cooperation. These standards call out four collaborative modes of operation: Power & Force Limiting, Hand Guiding, Safety Rated Monitored Stop, and Speed & Separation Monitoring (these are defined in ISO/TS 15066)…READ MORE

5. DMC vs. RFID in Manufacturing

The increasing discussions and regulations on complete traceability and reliable identification of products is making identification systems an inevitable part in manufacturing. There are two specific technologies that are very well received: The Data Matrix Code (DMC) and Radio Frequency Identification (RFID)…READ MORE

Measuring Distance: Should I Use Light or Sound?

Clear or transparent sensing targets can be a challenge but not an insurmountable one. Applications can detect or measure the amount of clear or transparent film on a roll or the level of a clear or transparent media, either liquid or solid.  The question for these applications becomes, do I use light or sound as a solution?

photoelectric.png
An application that measures the diameter of a roll of clear labels.

In an application that requires the measurement of the diameter of a roll of clear labels, there are a number of factors that need to be considered.  Are the labels and the backing clear?  Will the label transparency and the background transparency change?  Will the labels have printing on them?  All of these possibilities will affect which sensor should be used. Users should also ask how accurate or how much resolution is required.

Faced with this application, using ultrasonic sensors may be a better choice because of their ability to see targets regardless of color, possible printing on the label, transparency and surface texture or sheen.  Some or all of these variables could affect the performance of a photoelectric sensor.

Ultrasonic sensors emit a burst of short high frequency sound waves that propagate in a cone shape towards the target.  When the sound waves strike the target, they are bounced back to the sensor. The sensor then calculates the distance based on the time span from when the sound was emitted until the sound was received.

In some instances, and depending on the resolution required, a time of flight sensor may solve the above application. Time of Flight (TOF) sensors emit a pulsed light toward the target object. The light is then reflected back to the receiver. The elapsed time it takes for the light to return to the receiver is measured, thus determining the distance to the target. In this case, the surface finish and transparency may not be an issue.

Imagine trying to detect a clear piece of plastic going over a roll.  The photoelectric sensor could detect it either in a diffuse mode or with a retroreflective sensor designed for clear glass detection.  But what if the plastic characteristics can change frequently or if the surface flutters.  Again, the ultrasonic sensor may be a better choice and also may not require set up any time the material changes.

So what’s the best solution?  In the end, test the application with the worst case scenario.  A wide variety of sensors are available to solve these difficult applications, including photoelectric or ultrasonic. Both sensors have continuous analog and discrete outs.  For more information visit www.balluff.com.

 

The Need for Data and System Interoperability in Smart Manufacturing

As technology advances at a faster pace and the world becomes flatter, manufacturing operations are generally focused on efficient production to maximize profitability for the organization. In the new era of industrial automation and smart manufacturing, organizations are turning to data generated on their plant floors to make sound decisions about production and process improvements.

Smart manufacturing improvements can be divided roughly into six different segments: Predictive Analytics, Track and Trace, Error Proofing, Predictive Maintenance, Ease of Troubleshooting, and Remote Monitoring.IOLink-SmartManufacturing_blog-01To implement any or all of these improvements requires interoperable systems that can communicate effectively and sensors and devices with the ability to provide the data required to achieve the manufacturer’s goals. For example, if the goal is to have error free change-overs between production cycles, then feedback systems that include identification of change parts, measurements for machine alignment changes, or even point of use indication for operators may be required.  Similarly, to implement predictive maintenance, systems require devices that provide alerts or information about their health or overall system health.

Traditional control system integration methods that rely heavily on discrete or analog (or both) modes of communication are limited to specific operations. For example, a 4-20mA measurement device would only communicate a signal between 4-20mA. When it goes beyond those limits there is a failure in communication, in the device or in the system. Identifying that failure requires manual intervention for debugging the problem and wastes precious time on the manufacturing floor.

The question then becomes, why not utilize only sensors and devices with networking ability such as a fieldbus node? This could solve the data and interoperability problems, but it isn’t an ideal solution:

  • Most fieldbuses do not integrate power and hence require devices to have separate power drops making the devices bulkier.
  • Multiple fieldbuses in the plant on different machines requires the devices to support multiple fieldbus/network protocols. This can be cost prohibitive, otherwise the manufacturer will need to stock all varieties of the same sensor.
  • Several of the commonly used fieldbuses have limitations on the number nodes you can add — in general 256 nodes is capacity for a subnet. Additional nodes requires new expensive switches and other hardware.

IOLink-SmartManufacturing_blog-02IO-Link provides one standard device level communication that is smart in nature and network independent, thus it enables interoperability throughout the controls pyramid making it the most suitable choice for smart manufacturing.

We will go over more specific details on why IO-Link is the best suited technology for smart manufacturing in next week’s blog.

 

Safely Switch Off Cylinders While Transmitting Field Data

Is it possible to safely switch off cylinders while simultaneously transmitting field data and set up the system in accordance with standards? Yes!

In order to rule out a safety-critical fault between adjacent printed circuit board tracks/contact points (short circuit) according to DIN EN ISO 13849, clearance and creepage distances must be considered. One way to eliminate faults is to provide galvanic isolation by not interconnecting safety-relevant circuits/segments. This means  charge carriers from one segment cannot switch over to the other, and the separation makes it possible to connect the safety world with automation — with IO-Link. Safely switching off actuators and simultaneously collecting sensor signals reliably via IO-Link is possible with just one module. To further benefit from IO-Link and ensure safety at the same time, Balluff’s I/O module is galvanically isolated with a sensor and an actuator segment. The two circuits of the segments are not interconnected, and the actuator segment can be safely switched off without affecting the sensors. Important sensor data can still be monitoring and communicated.

The topological structure and the application of this safety function is shown in this figure as an example:

2D-SAGT-Betriebsanleitung_v2

  1. A PLC is connected to an IO-Link master module via a fieldbus system.
  2. The IO-Link master is the interface to all I/O modules (IO-Link sensor/actuator hubs) or other devices, such as IO-Link sensors. The IO-Link communication takes place via a standardized M12 connector.
  3. Binary switching elements can be connected to the galvanically isolated sensor/actuator hub (BNI IOL-355). The four connection ports on the left correspond to the sensor segment and the four ports on the right correspond to the actuator segment. Communication of the states is done via IO-Link.
  4. The power supply for both segments takes place via a 7/8″ connection, whereby attention must be paid to potential separated routing of the sensor and actuator circuits. Both the power supply unit itself and the wiring to the IO-Link device with the two segments must also ensure external galvanic isolation. This is made possible by separating the lines with a splitter.
  5. An external safety device is required to safely interrupt the supply voltage of the actuator segment (four ports simultaneously). Thus, the module can implement safety functions up to SIL2 according to EN62061/PLd and ISO 13849.  For example, this can happen through the use of a safety relay, whereby the power supply is safely disconnected after actuation of peripheral safety devices (such as emergency stops and door switches). At the same time, the sensor segment remains active and can provide important information from the field devices.

The module can handle up to eight digital inputs and outputs. If the IO-Link connection is interrupted, the outputs assume predefined states that are retained until the IO-Link connection is restored. Once the connection is restored, this unique state of the machine can be used to continue production directly without a reference run.

An application example for the interaction of sensors and actuators in a safety environment is the pneumatic clamping device of a workpiece holder. The position feedback of the cylinders is collected by the sensor segment, while at the same time the actuator segment can be switched off safely via its separately switchable safety circuit. If the sensor side is not required for application-related reasons, galvanically isolated IO-Link modules are also available with only actuator segments (BNI IOL 252/256). An isolated shutdown can protect up to two safety areas separately.

 

Non-Contact Transmission of Power & Data on Transfer Rails & Grippers

For press shops utilizing transfer rail systems, fixed sensor connections regularly cause frustration. Cables and contacts are often subject to heavy strain. Cables can wear out and break, damaged pins or mechanical collisions can cause hours of machine downtime, and the replacement of large multi-pin connectors comes at a high cost.

Inductive couplers offer an ideal solution: By using these non-contact, wear-free products you can eliminate pin connections and simplify job changeovers on the press. Inductive couplers transfer signals and power contact-free over an air gap. The quick-disconnect units are easy to use and require no maintenance, enabling you to meet new demands quickly. Mechanical wear is a thing of the past. This increases system availability, reduces cycle time and enhances the flexibility of workflow processes.

Inductive coupling example

Replace pin connections for transfer rails

Typically, two pin-based connectors connect the transfer rail to the transfer system on the press. The connections are on both the feed and exit sides of the rail to the control. If there is any misalignment of the connections, damage regularly occurs. By replacing the connectors with pin-free inductive couplers, the connections are simplified and repair work is minimized. Additionally you don’t have open pins exposed to the environment (dust, water, oil) that can also cause nuisances in the connection process.

Replace pin connections for grippers

To connect the transfer rail on each gripper, normally a pin-based connector is used. As the grippers are changed on each tooling change, the connectors become worn and damaged with regularity. By replacing the pin connector with non-contact inductive couplers, the two sensor signals are maintained but the maintenance of these connections is reduced dramatically. An additional “in-zone signal” verifies that the gripper is installed and connected. This provides assurance during operation.

Inductive couplers offer IO-Link functionality

Inductive coupling with IO-Link technology adds more benefits besides replacing the pin coupling. It allows users to transfer up to 32 bytes of data in addition to power for actuation or sensors. If you connect IO-Link enabled I/O hubs or valve connectors to the remote side, you can also store identification data on the IO-Link hub or valve. When the connection is established, the controller can request the identification data from the tool to ensure that the system is utilizing the correct tool for the upcoming process.

With pin based coupling you needed up to 4-5 seconds to first engage the tool and to mate the two ends of the pin couplers and then request the identification. With inductive couplers, the base only needs to be brought closer to the remote so that you quickly couple and identify the tool before engaging the tool — this takes less than a second. Additionally the base and remote do not need to be well aligned to couple. Misalignment up to 15-20 degrees of angular offset or 2-4 mm of axial offset still provides functionality.

The benefits at a glance

  • Power and signals transfer with pin-less connectivity
  • Reduced downtime due to rail or gripper repair
  • Know that the gripper is present and powered with in-zone signal
  • Inform the controller that the rail has power and connectivity to the sensors

To decide the right coupler for your next application visit www.balluff.com.

 

Industrial Safety Protocols

There are typically three or more communication levels in the modern factory which consist of:

  • Enterprise level (Ethernet)
  • Control level (Ethernet based industrial protocol)
  • Device/sensor level (various technologies)

IO-Link

The widespread use of control and device level communications for standard (non-safety) industrial applications led to a desire for similar communications for safety. We now have safety versions of the most popular industrial control level protocols, these make it possible to have safety and standard communications on the same physical media (with the appropriate safety hardware implemented for connectivity and control). In a similar manner, device level safety protocols are emerging to allow standard and safety communications over the same media. Safety Over IO-Link and AS-i Safety At Work are two examples.

This table lists the most common safety control level protocols with their Ethernet-based industrial “parent” protocols and the governing organizations:

chart1

And this table lists some of the emerging, more well-known, safety device level protocols with their related standard protocols and the governing or leading organizations:

Chart2
* Safety Over IO-Link is the first implementation of safety and IO-Link. The specification for IO-Link Safety was released recently and devices are not yet available.

Ethernet-based safety protocols are capable of high speed and high data transmission, they are ideal for exchanging data between higher level devices such as safety PLCs, drives, CNCs, HMIs, motion controllers, remote safety I/O and advanced safety devices. Device level protocol connections are physically smaller, much less expensive and do not use up IP addresses, but they also carry less data and cover shorter distances than Ethernet based protocols. They are ideal for connecting small, low cost devices such as E-stops, safety switches and simple safety light curtains.

As with standard protocols, neither a control level safety protocol, nor a device level safety protocol can meet all needs, therefore cost/performance considerations drive a “multi-level” communications approach for safety. This means a combined solution may be the best fit for many safety and standard communications applications.

A multi-level approach has many advantages for customers seeking a cost-effective, comprehensive safety and standard control and device solution which can also support their IIoT needs. Users can optimize their safety communications solutions, balancing cost, data and speed requirements.

Connecting Fluid Power to the Industrial IoT and Industry 4.0

The next industrial revolution has already begun. To remain a viable business, it’s time to invest in IIoT and Industry 4.0 applications, regardless of whether you are a “mechanical-only” company or not.Industry 4.0 & Industrial IoT

Industrial Internet of Things

IIoT is simply about connecting devices on the plant floor to a network. These connections provide new ways to generate and collect useful data. This network can provide visibility down into the machine, enabling predictive maintenance and big data analytics. With IIoT, we are able to improve overall equipment effectiveness and provide new insights into our business.

Industry 4.0

On a grander scale, Industry 4.0 is a blend of digitalization, new technology and practical decisions to improve manufacturing. Industry 4.0 aims to achieve unprecedented flexibility, efficient production and visibility at every level of production. Industry 4.0 has impact throughout our processes and across the supply chain. Its philosophy blends lean initiatives, automation, technology, materials, downtime reduction upgrades, and investments in overall equipment effectiveness. This philosophy keeps the current generation of manufacturers competitive in a global market. While the German government set this precedent for Industry 4.0, the entire manufacturing world must now take on this challenge.

Implementing IIoT and Industry 4.0

Standard systems like hydraulic power units (HPUs) are receiving a major boost by becoming IIoT-ready. Traditional on/off flow or pressure switches are upgrading to provide information beyond the simple switch points. In addition, analog devices like temperature, pressure, flow, and level transducers can become IIoT-ready through open standard technologies like IO-Link. These technologies add additional value by incorporating easy-to-report parameters, diagnostics, events and warnings. A standard HPU can become a smart power unit with minimal modification.

The value of IIoT increases with predictive maintenance, remote monitoring and ease of troubleshooting. Imagine not having to climb down into the oil-drenched pit of a stamping press to trouble shoot an issue. With IIoT-ready technologies, we can connect to the devices and know exactly what needs fixing. In addition, we can possibly predict the failure before it occurs. This can dramatically reduce machine downtime as well as the time spent in hazardous locations.

Selecting IIoT-ready technologies is only one step of the program to fully leverage the value of Industry 4.0. We must also analyze processes and determine how to implement flexibility into production. After that, we must then discuss where automation technology makes sense to support lean processes. Manufacturers can see into every aspect of their production while manufacturing hundreds of variations of product in the same line, all while assuring quality standards with virtually zero machine downtime.

The difference between Industry 4.0 and IIoT

Industry 4.0 is a cultural philosophy about how we can use increased visibility, flexibility and efficiency to be more competitive. IIoT’s connectivity is an enabling force for Industry 4.0. IIoT connects our devices, our data, our machines and our people to the advantage of our company and customers.  By embracing both, it is easier to achieve positive results and sustain global competitiveness.

Article originally posted on Hydraulics & Pneumatics.

Choosing the Best Position Sensor: Does Yours Measure Up?

Reliable electronic measurement is something that is always needed in industrial automation. Production interruptions and unexpected downtime will cripple even the best manufacturers if they do not have the appropriate measurement technology in place.

Whether it’s monitoring the position of a hydraulic jack or determining the proper position of a flood gate on a dam, be sure to choose the best option for precision, accuracy, and most importantly, reliability.

Strings Holding Down Production 

String potentiometers, also known as string pots, yo-yo sensors, cable-extension transducers, and a few other names, have been used for electronic measurement for the last 40 years.

These devices use braided steel wires (“strings”) wrapped around spools and require the release of the coiled string.

11_7_18

In an industrial assembly application, a typical scenario might involve wire being integrated into a manufacturing platform that moves from one assembly station to the next. As the string pot’s spool extends or retracts, position is measured by a rotational sensor/potentiometer that rests outside the spool and will trigger based on the position of the metal wire.

While string pots are often used in many sectors (heavy industry, crude oil processing, waste water treatment, etc.), they come with potential issues that make then unsuitable for others:

  • The wire will eventually jam from rust, mechanical glitches, or other environmental factors
  • The springs in the reel often fail over time
  • The high contact nature of the devices causes friction among the components, which leads to excessive wear and failure after a few thousand rotations

Combined, these things lead to expensive downtime/loss of production and costly repairs. A measurement system should not be a consumable item or an item with an expected but unpredictable maintenance interval. A measurement system should be designed with longevity and reliability in mind.

Right Solution for Your Industry

The assembly industry is not the only one that benefits from highly accurate position measurement. Whether it’s metallurgy, plastics and rubber, energy, or woodwork —­  the advanced, versatile, and resilient technology is required to thrive in high speed and demanding applications.

Fortunately, magnetostrictive linear transducers were developed to provide the kind of reliable position measurement that industry demands.

Instead of a trouble-prone mechanism, magnetostrictive non-contact linear transducers work with a movable free-floating or captive magnet that rides the length of a sensing rod as it follows the target object.

During operation, a very short-duration pulse is generated along the sensing element. This is known as the waveguide. The resulting magnetic field interacts with the magnetic field of the position magnet and generates a mechanical force on the sensing element. This force ripples along the waveguide at a faster-than-sound velocity that is detected by the sensor electronics, and is converted into an electrical pulse.

Using a very accurate high-speed clock, the time interval between the initial current pulse and return pulse is measured and converted into an absolute position value.

The end result is constant, precise, accurate, and smooth position measurement.

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As an example: A high speed punch press requires position monitoring down to the millisecond. The punch press is designed to move very quickly back and forth in rows, punching holes in precise locations. When one row is finished, the unit moves forward and does the next. As the punch continues back and forth and up the rows, the sensor follows the position of the press, transmitting position feedback to the control system. This ensures the press stays on the appropriate track and punches where it should.

A contact device would not be suitable for this kind of operation, as the amount of friction caused from the speed and repetition would wear the sensor down too quickly and cause failure.

Fortunately, magnetostrictive linear sensors are widely available, come in a variety of form factors, and are truly non-contact, with some “floating” versions riding as much as 15mm off the surface of the transducer body. No contact means no wire binding issues and the lack of contact also means a lack of impact damage, which will help the sensor survive longer than a string potentiometer.

A measuring distance from 1 to 300 inches, offers short and long range capabilities.

Moreover, compared to string pots, magnetostrictive linear sensors, require fewer components. This means fewer parts to replace and maintain, which results in a reduction in overall equipment and maintenance costs.

Adaptable to nearly any industrial control system, these sensors are available in common analog (0….10V or 4….20 mA), as well as a variety of digital interfaces. This includes digital start/stop, synchronous serial interface, as well as network interfaces (IO-Link, Ethernet/IP, Profinet).

Tying it All Together

Though both string pots and magnetostrictive linear transducers are employed for electronic measurement, selecting the one that is best for your application will maximize manufacturing efficiency, increase machine uptime, and cut costs. All while ensuring your process keeps running smoothly and your customers get the parts and products they need on time.

Traceability of production material with RFID

As we progress toward a more automated factory, the need to more efficiently manage what happens prior to the production process has become apparent. Tracking of raw material and production components from the dock door to the warehouse is quickly evolving from a best guess estimate to real-time inventory levels driven by production. Essentially, we are moving from a practice of holding just-in-case inventory to Just-in-Time (JIT) inventory. The JIT concept helps to optimize the amount of in-house inventory based on production. In addition, the entire supply chain benefits because the levels of raw goods inventory upstream can be managed more efficiently and forecasted with more accuracy.

RFID and barcode technology have played a critical role in the actual production process for decades, but its benefits are currently being leveraged in other areas of the plant as well. Whether its tracking every item or every pallet that comes into the receiving dock, ID traceability provides visibility where it did not exist before.

Traceability of production material 

Upon receiving a pallet with raw material, the 2D matrix code on the shipping label is read by a barcode scanner. The relevant data needed for the further traceability process is transferred onto the stack of trays which contain UHF carriers. The number of carriers is saved together with the traceability data in a database. This process takes place at one single station and the data is updated immediately to represent the inventory level.

Transmission of incoming goods data on the transponder

Automated review of loaded pallets

Based on the material number, the system contains a standard load for the number of trays on the pallet. An automatic screening takes place to determine if all transponders on the pallet are registered. In case of a difference between the registered data and the expected data, an error message pops up to indicate the need for manual intervention. This process allows for proactive management of inventory to prevent false inventory levels or goods that cannot be accounted for.

Key Features of a traceability solution:

  • Corresponds to the global ISO standard
  • Suitable for attachment to major control systems via bus interfaces and higher level IT systems
  • Variety of accessories available for easy integration into different applications

To learn more about RFID technology, visit www.balluff.com.