Industrial Technology - Linked-in Industrial Technology - Twitter Industrial Technology - News Feed
Latest Issue

Practical sensor integration: Your questions answered

Practical sensor integration: Your questions answered

Charlie Walker, Smart Sensor specialist with SICK UK, outlines the tools needed for sensor integration and how they can used to enable rapid process improvements.

There was a time when sensors were simple switches, and their manufacturers just hardware suppliers. All that has all changed. Realising the full potential of intelligent sensors in an interconnected and data-rich world, means integrating them with one another, and with wider machine, factory, logistics and enterprise networks.

For most of us, Industry 4.0 is all about a step-by-step growth in connectivity and data transparency at the machine or plant level. By building smart sensor applications, machine designers and users deliver Industry 4.0 capability one process at a time. Users are presented with new creative opportunities to rethink their applications in configurations that would have been inconceivable until relatively recently, while sensor manufacturers have become software developers and networking specialists.

Once you dip your toes in the developing world of Smart Sensor integration, you will see how quickly process improvements can be made. You will be rewarded with better machine availability, and more operational flexibility and responsiveness.

But what exactly is sensor integration, and, with a wealth of new language, terminology and concepts, where do you begin?

What is sensor integration? If sensors are the “eyes and ears” that tell us what’s around them, then sensor integration is the process of embedding that knowledge into a system. Whether you are a car or a robot arm, you need sensor integration to fuse together the gathered data to make sense of the environment around you. Imagine trying to make a cup of tea without being able to see the kettle or feel when we have picked it up; integrated sight and pressure feedback together make the task possible. Sensors are not just switches; they are the building bricks of applications. In some cases, they can even process applications, or ‘Smart Tasks’, all by themselves.

How has IO-Link helped? IO-Link was certainly the breakthrough point-to-point open communications channel that ‘bridged the final metre’ between sensors or actuators and the control system. Enabled by IO-Link, sensors cooperate at the coalface of automation. They interpret, act upon and communicate the information they collect to an IO-Link Master so it can be transmitted via the factory ethernet network to a machine controller, such as a PLC. 

Are there different levels of sensor integration? Some sensors just provide on/off signals – is the part present or not? Some use IO-link to give additional data to the control system. Soon there will be multi-use sensors which include multiple technologies, for example piston position coupled with vibration and angular velocity for end of arm tooling.  Some connect to the cloud, ensuring accurate tracking of data to optimise operating efficiency and uptime.

So, is all this integration most useful for the enterprise level or the local level? Integration of hardware takes place at a local level within the systems and control architecture - but the data that this generates can be shared not just at the machine level, but via cloud-based systems. Firstly, that data can be monitored and trended on a PC, machine HMI or cloud-based dashboard. 

It also has the potential be used in ERP (Enterprise Resource Planning) and MES (Manufacturing Execution System) software; indeed this is seen as fundamental to the future of Industry 4.0 manufacturing and logistics. So, it’s wise to be ready and build up inventories of smart devices that can deliver when the challenge is asked of them, as well as immediately giving you more real-time operating feedback and aiding your planned maintenance.

Data transparency enables trending and gives us the ability to understand so much more about a system.  From Overall Equipment Effectiveness (OEE) to Deep Learning, it is the integration of the data that allows for a user to become more aware of what is happening within a system.

What practical steps can I take towards greater connectivity? SICK has been predicting for a long time that digitisation, intelligence and networking is going to increase until eventually manufacturing and logistics systems will control and optimise themselves – all using the data from our sensors.

You could be forgiven for thinking this all seems a bit too much of a ‘big picture’ to be of practical value right now. You may even wonder how all this exchange of data doesn’t just become one huge Tower of Babel, thwarted by different proprietary protocols and bogged down, as increased amounts of data are exchanged. The answer to this lies in integration gateways and devices, starting with the IO-link Masters that act as the translators, and also sometimes as localised controllers, to aggregate and route the data efficiently. They deal with the data at a local level, while making it visible globally.

When do you need other devices to link sensors in plant and machinery? Whenever a device does not use the same protocols as the cloud it wants to connect with, it will need a gateway to handle the transfer of data to the cloud. For example, an IO-Link sensor needs a master, and the master may need a cloud gateway of one sort or another. The gateway needs to be able to talk the right language to both the connected device and the higher-level cloud or network it is linked to.

SICK has already begun to roll out a portfolio of devices to facilitate sensor integration into fieldbus environments and higher automation hierarchies.  But the terminology for these gateways and integration hubs can sound very similar.

What’s the difference between IO-Link Masters, Sensor Hubs, Sensor Integration Machines, Sensor Integration Gateways and Telematic Data Collectors? An IO-Link Master sits on a higher-level bus system, such as PROFINET or EtherCAT. It acts as a gateway for IO-Link data to be passed on to the PLC or higher-level systems.

SICK’s SIG200 Sensor Integration Gateway is an IO-Link Master with an on-board web server that collects, combines, evaluates and transmits signals from IO-Link devices from any manufacturer. SICK’s innovative DualTalk technology means the SIG200 needs only one cable to communicate simultaneously via the fieldbus with the machine controller and with higher-level enterprise or web-based systems. It’s the first of a family of intelligent Industry 4.0 gateways designed to work as both IO-Link Masters and small, distributed logical control systems in one.

A sensor hub is an IO-Link device, such as the SICK SIG100 that connects to an IO-Link Master.  It takes a number of on/off sensors that connect to it and it squeezes all their outputs into one string that can be passed on up the chain to the PLC. SICK’s SIG100 sensor hub can be used to bundle up to twelve standard I/Os in a single IO-Link data packet, which can then be communicated to machine controllers and cloud-based systems via the SIG200. A maximum of 52 I/Os can be connected to one SIG200 by using the SICK SIG100.

Sensor Integration Machines (SIMs) are hardware-based programmable devices that also have configurable on-board software such as SICK AppSpace, so they can be used to process many different tasks, including more complex machine vision applications, for example. They also include some or all of the functionality of an IO-Link Master.

The SICK SIM1000 and SIM2000 Sensor Integration Machines collect and evaluate data from multiple sensors working together at the field-level via standard interfaces, including Ethernet, IO-Link, CAN and Serial.  With up to four Ethernet ports, the SICK SIM1000 and SIM2000 can support interfaces for cameras, lighting, LiDAR scanners, encoders, photoelectric or displacement sensors, as well as to higher level controls and to the Cloud. The multi-sensor outputs, values and results can be used to drive typical industrial automation applications such as camera-based inspection, measurement, or identification of objects. 

The term Gateway can mean different things depending on what is using the ‘gate’. In the case of sensor data, it may be the SICK Sensor Integration Gateways. More generally, a cloud gateway is a device that takes all sorts of data and passes it to the next level via the relevant protocol. Think of it as a translator. An example of this would be SICK’s TDC (Telematic Data Collector), used to aid real-time condition monitoring and predictive maintenance.

The SICK TDC collects and processes sensor outputs and data in stationary and mobile machinery, together with GPS localisation information, and enables them to be displayed, monitored, recorded and analysed via a server or cloud system. By transferring data via a mobile communications protocol (MQTT), a real-time overview of selected plant and processing parameters can be provided, and SMS text or email alarms can be configured.

The SICK TDC system also enhances system transparency to SICK and third-party sensors compatible with Ethernet, CAN, RS232, RS485, 1-Wire and UART interfaces. Output communications can be via cable, wireless signal or GSM.

A data collector is any device that is able to accept and pass on sensor data. The SICK SIG200 can take sensor data and pass it on over REST API to the cloud or fieldbus to the machine controller. The SICK TDC can take data direct or via REST API and pass it to the cloud or a local network storage solution.

Is there an easy way of detecting all IO-Link devices in a machine? Yes, this is simple using SICK’s FieldEcho software. SICK FieldEcho closes the remaining gaps in integration and makes all IO-Link devices visible, providing direct access to process and service data and enabling the IODD device descriptions to be automatically downloaded.

The FieldEcho has a well-designed user interface opened with a browser or integrated into the machine or plant HMI.  It visualises all configured IO-Link Masters, IO-Link sensors and actuators, and displays their status.

These parameter values, diagnostic messages, events and alarms from the IO-Link devices are hardly ever needed by the control program of the machine, but they are invaluable for decision making both at the plant level, and in MES or cloud applications. Control communication via OPC UA or TCP/IP, as well as data exchange with IT- or cloud-based applications via REST, enables integration into any Industry 4.0 applications.

How does SICK envisage the future development of sensor integration? Industrial automation is developing rapidly.  SICK’s intelligent sensors collect data, evaluate it in real time, adapt to their environment and communicate over the network. It is networked production and control processes, working in complex machine environments, that will shape our industrial future. The degree of digitalisation in future will mean smart factories will organise themselves using huge amounts of up to date information to make independent decisions. This information will be provided by smart sensors.

Download pdf

Other News from Sick (UK) Ltd

Sick releases all-in-one muting sets for its deTem4 active/passive light curtains

Latest news about Sensors and systems

Additional Information
Text styles