Automated Welding With IO-Link

IO-Link technologies have been a game-changer for the welding industry. With the advent of automation, the demand for increasingly sophisticated and intelligent technologies has increased. IO-Link technologies have risen to meet this demand. Here I explain the concepts and benefits of I-O Link technologies and how they integrate into automated welding applications.

What are IO-Link technologies?

IO-Link technologies refer to an advanced communication protocol used in industrial automation. The technology allows data transfer, i.e., the status of sensors, actuators, and other devices through a one-point connection between the control system and individual devices. Also, it enables devices to communicate among themselves quickly and efficiently. IO-Link technologies provide real-time communication, enabling continuous monitoring of devices to ensure optimal performance.

Benefits of IO-Link technologies

    • Enhanced data communication: IO-Link technologies can transfer data between the control system and sensors or devices. This communication creates an open and transparent network of information, reflecting the real-time status of equipment and allowing for increased reliability and reduced downtime.
    • Cost-efficiency: IO-Link technologies do not require complicated wiring and can significantly reduce material costs compared to traditional hardwired solutions. Additionally, maintenance is easier and more efficient with communication between devices, and there is less need for multiple maintenance employees to manage equipment.
    • Flexibility: With IO-Link technologies, the control system can control and monitor devices even when not attached to specific operator workstations. It enables one control system to manage thousands of devices without needing to rewrite programming to accommodate different machine types.
    • Real-time monitoring: IO-Link technologies provide real-time monitoring of devices, allowing control systems to monitor failures before they occur, making it easier for maintenance teams to manage the shop floor.

How are IO-Link technologies used in automated welding applications?

Automated welding applications have increased efficiencies and continuity in processes, and IO-Link technologies have accelerated these processes further. Automated welding applications have different stages, and each step requires real-time monitoring to ensure the process is efficient and effective. IO-Link technologies have been integrated into various parts of the automated welding process, some of which include:

    1. Positioning and alignment: The welding process starts with positioning and aligning materials such as beams, plates, and pipes. IO-Link sensors can detect the height and gap position of the material before the welding process begins. The sensor sends positional data to the control system as a feedback loop, which then adjusts the positioning system using actuators to ensure optimal weld quality.
    2. Welding arc monitoring: The welding arc monitoring system is another critical application for IO-Link technologies. Monitoring the arc ensures optimal weld quality and runs with reduced interruptions. IO-Link temperature sensors attached to the welding tip help control and adjust the temperature required to melt and flow the metal, ensuring that the welding arc works optimally.
    3. Power supply calibration: IO-Link technologies are essential in calibrating the power output of welding supplies, ensuring consistent quality in the welding process. Detectors attached to the power supply record the energy usage, power output and voltage levels, allowing the control system to adjust as necessary.
    4. Real-time monitoring and alerting: Real-time monitoring and alerting capabilities provided by IO-Link technologies help to reduce downtime where machine health is at risk. The sensors monitor the welding process, determining if there are any deviations from the set parameters. They then communicate the process condition to the control system, dispatching alerts to maintenance teams if an issue arises.

Using IO-Link technologies in automated welding applications has revolutionized the welding industry, providing real-time communication, enhanced data transfer, flexibility, and real-time monitoring capabilities required for reliable processes. IO-Link technologies have been integrated at various stages of automated welding, including positioning and alignment, welding arc monitoring, power supply calibration, and real-time monitoring and alerting. There is no doubt that the future of automated welding is bright. With IO-Link technologies, the possibilities are endless, forging ahead to provide more intelligent, efficient, and reliable welding applications.

IO-Link Benefits in Robotic Weld Cell Tooling

By Scott Barhorst

Working previously as a controls engineering manager in robotic welding, I have seen some consistent challenges when designing robotic weld cell systems.

For example, the pre-engineered-style welding cells I’ve worked with use many types of tooling. At the same time, space for tooling and cabling is limited, and so is the automation on board, with some using PLC function and others using a robot controller to process data.

One approach that worked well was to use IO-Link in the systems I designed. With its simple open fieldbus communication interface and digital transmission, it brought a number of benefits.

    1.  IO-Link’s digital signals aren’t affected by noise, so I could use smart sensors and connect them with unshielded 4-pin cables.
    2.  Expandability was easy, either from the Master block or by adding discrete I/O modules.
    3.  IO-Link can use the ID of the block to identify the fixture it is associated with to make sure the correct fixture is in the correct location.
    4.  Cabling is simplified with IO-Link, since the IO-Link Master can control both inputs, outputs, and control valve packs. That means that the only cables needed will be 24V power, Ethernet, weld ground (depending on the system), and air.
    5.  Fewer cables means less cost for cables and installation, cable management is improved, and there are fewer cables to run through a tailstock or turntable access hole.

One system I designed used 1 IO-Link Master block, 3 discrete I/O modules, and 1 SMC valve manifold controlled via IO-Link. This tooling had 16 clamps and 10 sensors, requiring 42 total inputs and control of 16 valves. The system worked very well with this setup!

An additional note: It’s good to think beyond the process at hand to how it might be used in the future. A system built on IO-Link is much more adaptable to different tooling when a change-over is needed. Click here to read more about how to use IO-Link in welding environments.

 

 

 

 

 

The Emergence of Device-level Safety Communications in Manufacturing

Manufacturing is rapidly changing, driven by trends such as low volume/high mix, shorter lifecycles, changing labor dynamics and other global factors. One way industry is responding to these trends is by changing the way humans and machines safely work together, enabled by updated standards and new technologies including safety communications.

In the past, safety systems utilized hard-wired connections, often resulting in long cable runs, large wire bundles, difficult troubleshooting and inflexible designs. The more recent shift to safety networks addresses these issues and allows fast, secure and reliable communications between the various components in a safety control system. Another benefit of these communications systems is that they are key elements in implementing the Industrial Internet of Things (IIoT) and Industry 4.0 solutions.

Within a typical factory, there are three or more communications levels, including an Enterprise level (Ethernet), a Control level (Ethernet based industrial protocol) and a Device/sensor level (various technologies). The popularity of control and device level industrial communications for standard control systems has led to strong demand for similar safety communications solutions.

Safety architectures based on the most popular control level protocols are now common and often reside on the same physical media, thereby simplifying wiring and control schemes. The table, below, includes a list of the most common safety control level protocols with their Ethernet-based industrial “parent” protocols and the governing organizations:

Ethernet Based Safety Protocol Ethernet Based Control Protocol Governing Organization
CIP Safety Ethernet IP Open DeviceNet Vendor Association (ODVA)
PROFISafe PROFINET PROFIBUS and PROFINET International (PI)
Fail Safe over EtherCAT (FSoE) EtherCAT EtherCAT Technology Group
CC-Link IE Safety CC-Link IE CC-Link Partner Association
openSAFETY Ethernet POWERLINK Ethernet POWERLINK Standardization Group (EPSG)

 

These Ethernet-based safety protocols are high speed, can carry fairly large amounts of information and are excellent for exchanging data between higher level devices such as safety PLCs, drives, CNCs, HMIs, motion controllers, remote safety I/O and advanced safety devices. Ethernet is familiar to most customers, and these protocols are open and supported by many vendors and device suppliers – customers can create systems utilizing products from multiple suppliers. One drawback, however, is that devices compatible with one protocol are not compatible with other protocols, requiring vendors to offer multiple communication connection options for their devices. Other drawbacks include the high cost to connect, the need to use one IP address per connected device and strong influence by a single supplier over some protocols.

Device level safety protocols are fairly new and less common, and realize many of the same benefits as the Ethernet-based safety protocols while addressing some of the drawbacks. As with Ethernet protocols, a wide variety of safety devices can be connected (often from a range of suppliers), wiring and troubleshooting are simplified, and more data can be gathered than with hard wiring. The disadvantages are that they are usually slower, carry much less data and cover shorter distances than Ethernet protocols. On the other hand, device connections are physically smaller, much less expensive and do not use up IP addresses, allowing the integration into small, low cost devices including E-stops, safety switches, inductive safety sensors and simple safety light curtains.

Device level Safety Protocol Device level Standard Protocol Open or Proprietary Governing Organization
Safety Over IO-Link/IO-Link Safety* IO-Link Semi-open/Open Balluff/IO-Link Consortium
AS-Interface Safety at Work (ASISafe) AS-Interface (AS-I) Open AS-International
Flexi Loop Proprietary Sick GmbH
GuardLink Proprietary Rockwell Automation

* 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.

The awareness of, and the need for, device level safety communications will increase with the desire to more tightly integrate safety and standard sensors into control systems. This will be driven by the need to:

  • Reduce and simplify wiring
  • Add flexibility to scale up, down or change solutions
  • Improve troubleshooting
  • Mix of best-in-class components from a variety of suppliers to optimize solutions
  • Gather and distribute IIoT data upwards to higher level systems

Many users are realizing that neither an Ethernet-based safety protocol, nor a device level safety protocol can meet all their needs, especially if they are trying to implement a cost-effective, comprehensive safety solution which can also support their IIoT needs. This is where a safety communications master (or bridge) comes in – it can connect a device level safety protocol to a control level safety protocol, allowing low cost sensor connection and data gathering at the device level, and transmission of this data to the higher-level communications and control system.

An example of this architecture is Safety Over IO-Link on PROFISafe/PROFINET. Devices such as safety light curtains, E-stops and safety switches are connected to a “Safety Hub” which has implemented the Safety Over IO-Link protocol. This hub communicates via a “black channel” over a PROFINET/IO-Link Master to a PROFISafe PLC. The safety device connections are very simple and inexpensive (off the shelf cables & standard M12 connectors), and the more expensive (and more capable) Ethernet (PROFINET/PROFISafe) connections are only made where they are needed: at the masters, PLCs and other control level devices. And an added benefit is that standard and safety sensors can both connect through the PROFINET/IO-Link Master, simplifying the device level architecture.

Safety

Combining device level and control level protocols helps users optimize their safety communications solutions, balancing cost, data and speed requirements, and allows IIoT data to be gathered and distributed upwards to control and MES systems.

 

Five things to consider before selecting an RFID system

So, you have reached a point where you believe RFID is going to be the best solution. Now what? One of the most critical phases of a RFID project is deciding which product is going to address the application. While the planning stage can be highly conceptual, the hardware selection is truly a close-up inspection. This is where the rubber meets the road.

Here are the top five things, in no specific order, to consider after you have determined RFID is the appropriate technology for your application:

  1. Throughput

How much and how fast? How much data will be written to the tag and how much data will be read from the tag at each read point? Will the tag be moving during the read/write or will it stop in front of the antenna? Some RFID systems are capable of handling a large amount of data, while others are designed to read only small amounts of data. It is also important to consider if your data requirements will change in the near future.

  1. Read/Write Range

What is the required distance from the antenna to the tag? Will the tag be presented to the antenna at the same distance every time? Multiple frequency ranges can limit some systems to a few millimeters, while others are capable of communicating up to six or seven meters.

  1. Form factor

How much space do you have to mount both the reader and the tag? If space is limited, you can choose a system in which the antenna and the processor are combined in one housing. As for the tags, they can be as small as a grain of rice or as large as a license plate. The key is to make sure the equipment will not interfere with your process.

  1. Communication Protocol

How will the RFID processor “talk” to the control system? This is critical in a mixed control environment where multiple brands of PLCs or servers are present. What communication protocol do your controls engineers prefer — Ethernet/IP, Profinet, CC-Link, TCP/IP, etc?

  1. Environment

Where will the equipment actually be mounted? Does anything stand in the way of getting a clear read? Are there metal beams, tanks of liquid, or even operators walking in between the tag and antenna? This is probably the most critical of all the considerations because constant interference will block the antenna from reading or writing to the tag. While RFID technology has come a long way in recent years, metal and liquid can still affect the RF waves.

Keep these five things in mind and your RFID implementation will go a lot smoother!

To learn more about RFID solutions visit www.balluff.com.