IoT and programmability are leading encoder trends (a Motion Trends Report)

What key trends are driving the encoder market? We put the question to several of the top encoder manufacturers to get their perspective on trends in the encoder industry as well as how developments in other industries are impacting their business. Here’s what they told us.

With respect to the IoT and IIoT, what kinds of capabilities do your components or engineered designs incorporate to support functions related to fog computing on local networks?

Jonathan Dougherty • Product Specialist | HEIDENHAIN: With the emergence of IoT in the industrial world, more companies are looking to receive more information from encoders than just the position. Things like environmental information, diagnostic data, and time in motion analysis can all provide customers with valuable information that they were not able to access before. For HEIDENHAIN, our main step into this world has been through our Leine & Linde brand encoders. With these devices, we have integrated a full-service Advanced Diagnostic System (ADS) which provides diagnostic and condition monitoring information back to the control through Ethernet communication. With this information, users are able to view and analyze the aspects of the encoder that affect its performance. They also have the ability to more accurately predict a potential encoder failure, which allows them to practice more proactive maintenance procedures to avoid unnecessary downtime.

Describe what you’re seeing in time-sensitive networking (TSN) and its application in motion applications.

Jonathan Dougherty • HEIDENHAIN: Ethernet has established itself in industrial automation technology, and is widely accepted. However, there is one area of applications where standard Ethernet has not been able to gain inroads; network communication with real-time requirements.

TSN tries to respond to this by providing clocked end-to-end transmission with real-time requirements , while scheduling and traffic-shaping to make a shared transmission of communication streams with different priority levels possible in “real-time”. However, from a competent level, the big question is “What does real-time mean?” Currently the use of TSN instead of fieldbus has been tested to 1 msec cycle time at 100 nsec jitter, which is perfectly acceptable for diagnostic information but not quite enough for dynamic information used in position and speed loops.  However, there are organizations and company partnerships that are looking to increase the viability of TSN (possibly partnered with OPC UA) for component level communication. This is something certainly to monitor and take part in to see what the future holds for TSN on the component level.

How does your company ensure interoperability between its offerings and product families?

Christian Fell • POSITAL FRABA: An important link in the interoperability chain is the choice of communications protocols. Our company provides support for numerous communications interfaces, including the PROFIBUS and CANopen family of fieldbus protocols (including CAN-based protocols like DeviceNET and SAE J1939). For large factory systems, we offer industrial Ethernet communications such as EtherNet/IP, EtherCAT and PROFINET, all of which are suitable for real-time controls.

For servomotors or feedback-controlled stepper motors, we are enthusiastic about the SSI and BiSS communications systems. These are open-source protocols with no licensing fees. BiSS protocols are highly functional and support several wiring configurations, including 2 and 4-wire single-cable setups.

Jonathan Dougherty • HEIDENHAIN: For HEIDENHAIN, we have the benefit of supporting a multitude of available brands in our markets. Brands like ETEL, RSF, Acu-Rite, Leine & Linde, Renco, LTN, Numeric Jena, and more are all under the HEIDENHAIN umbrella. Each product offering has it’s unique position and specialty in the market and we take care to focus each brand on what aspects of technology in which they excel, but each brand also benefits from the added R&D capabilities provided by being part of the larger HEIDENHAIN group. This provides a balanced symbiotic relationship where each brand can excel at their area of focus and distinguish themselves while also having the backing of a solid foundation in HEIDENHAIN.

HEIDENHAIN’s new LC 201 absolute linear scale is a single-section METALLUR tape encoder suited for use in linear motor applications that may be required to reach high acceleration levels within the linear drive systems. They are well suited in the machine tool and aerospace machining sectors, but will also work in applications for electronics, automation, medical technology and metrology industries.

What are some trends you see in industry — or a recent project your company supported?

Christian Fell • POSITAL FRABA: The trend we see in AGVs, collaborative robots, and other robots is a need for low-cost, high-quality position and motion feedback. We are focusing our energies on making sure that our position and motion sensor products can deliver the accuracy, reliability and durability that the industry needs, while keeping cost down, both in terms of component price and the cost of installing components in new or existing designs.

Our new absolute kit (modular) encoders are designed to be straightforward to install in servomotors, feedback-controlled stepper motors and robotic joints, while delivering significant performance advantages over traditional resolvers or incremental encoders.

Control and safety assurance systems for construction, off-road and military equipment have become much more sophisticated in the past decade. An important development for us in this space is our new dynamic inclinometer. Inclinometers (tilt sensors) provide feedback on the position of components such as excavator booms and crane jibs. They are also used for tip-over prevention systems for vehicles, lifting platforms and other mobile machines. These devices typically make use of MEMS (Micro Electro-Mechanical Systems) accelerometer modules that detect the effect of gravity on the position of a tiny mass suspended in an elastic support structure.

However, accelerations caused by equipment motion can also make the mass move relative to its supports, introducing measurement errors. POSITAL’s engineers have eliminated this problem by adding a set of 3D MEMS gyroscopes to the inclinometers. A smart algorithm combines signals from the gyroscopes and the accelerometer modules to compensate for the effects of acceleration, with the result that the new dynamic TILTIX inclinometers can be used reliably wherever sudden movements, shocks or vibrations are likely to be encountered.

These programmable analog encoders from Posital Fraba can be customized to meet specific application requirements. Programming can be carried out at the factory, in a distributor’s warehouse or at the customer’s job site via the company’s UBIFAST programming tool.

Mass customization has also been a key component in our company’s product strategy for over a decade. Our sensors are used in applications ranging from precision manufacturing machinery to rugged construction equipment. To meet this wide range of requirements, we have developed a data-centered industrial process that gives us the ability to build the customer exactly what they need, quickly and efficiently, while keeping costs at the mass production level.

Products are assembled on an as-ordered basis from a set of largely interchangeable components and sub-assemblies. Once a device has been assembled, it’s calibrated and subjected to a full set of QA tests. Assembly records and test results are stored in the production database so that each device’s history is entirely traceable.

Our product range can be accessed through our online Product Finder tool. Potential customers can specify the performance characteristics, mechanical features and communications options they are looking for, then receive information on products that meet these requirements, including datasheets, CAD drawings and manuals. Once a device has been selected and ordered, delivery can usually be accomplished in less than a week.

Jonathan Dougherty • HEIDENHAIN: Specifically in the service robotics world, we have seen an increased demand for low-cost absolute feedback for inclusion in robotic joint rotary axes. For these products, we have seen great success with our inductive sensing solutions which provide high quality position information in a low height and compact form factor, which suit the needs of the OEMs in this industry.

On the industrial robotics side, we’ve seen an increased demand for highly accurate machining operations on very large components, specifically in the aerospace and automotive markets. For these applications, we’ve designed solutions to use secondary feedback devices to enable a level of accuracy at the tool center point that was not previously possible.

Tell us about any selector, sizing, or sales software you use or offer to customers and how these tools are changing how design engineering is done.

Jonathan Dougherty • HEIDENHAIN: Our most popular selector tool is through our Leine & Linde brand and can be found online at leinelinde.com/products/productfinder.

This tool provides enormous value to engineers looking for a product and allows them to specify exactly the type of encoder they’re looking for with an easy to use interface that guides them through the process and provides options for various sizes, interfaces, electrical connections, and more. However, we also are looking to expand our selector software to include application questions, to better provide feedback on what encoders will fit to a specific industry’s needs based on our experience in the market. Be on the lookout for this feature soon to be released on heidenhain.us.