Drives & Controls Magazine February 2023

40 n SENSORS February 2023 www.drivesncontrols.com E xperts will tell you that Industry 4.0 is different from the IoT, and machine- to-machine communications (M2MC), but to those of us with a more down-to-earth understanding, they are effectively all the same – ways of significantly increasing the amount of data collected from production machinery and processing it in real time to produce better information which, in turn, leads to increased productivity. The amount of data produced has been growing for many years and usually leads to better decision-making. However information overload can make it difficult to pick the important information from a sea of data, and to make appropriate decisions. But this is a human condition and can be treated by using computers to categorise the data automatically by importance and to display it appropriately (including emergency alarms, if necessary). This real-time management of large quantities of data is a well-developed discipline and has become known as“big data”. This probably started in the control systems used to run petrochemical refineries, spread to other data-intense applications, and has evolved from there. It is now widely applied in many industries from oil and gas, to retail management, weather forecasting, battlefield management and telecoms network operations. Making data Before we can use data, we have to produce it. This is where sensors come in. They are, in essence, the building blocks of Industry 4.0. There are many types of sensor, from simple on/off switches and counters to sophisticated sensors such as my company’s TorqSense devices, which continuously measure the torque generated by rotating shafts. It seems inevitable that the technology of sensors is going to develop rapidly over the coming years. We already have sensors to measure just about every useful parameter, so new types of sensor are not needed. The forthcoming developments will take us in new directions. One obvious requirement is for“intelligent” sensors with on-board (or at least local) data- processing capabilities. Instead of sending raw data off to a central control system for processing, these devices do some or all of the processing in the field. They produce refined information, which may be in different formats, each suitable for a particular type of user. We pioneered this sort of distributed intelligence some years ago. Not all users want this capability, but those that do can reap considerable practical benefits and are essentially setting up their own bespoke Intranet of Things. With the take-up of the IoT and similar concepts, the demand for intelligent sensors will probably grow exponentially. With the groundwork and fundamental developments already put in place by technology-led companies, the trend is free to develop unhindered. Islands of control A logical development of the intelligent sensor is the sensor LAN (local area network) or cluster. In this, several sensors feed either raw data or processed information into a nearby controller for further processing. This results in a highly distributed control system architecture with attributes such as robustness, speed, agility and flexibility. Sensor LANs will be able to include different types of sensor, so could measure many diverse variables. They could also monitor, say, temperatures in multiple locations and/or the torque in different drive shafts. The level of information produced and forwarded to different users could be highly developed. Other likely sensor trends include cost reduction, miniaturisation, standardisation of communications protocols, plug-and-play capabilities and signal quality enhancements. Sensors may also need to develop the ability to bypass central control systems and to supply information straight to the cloud or remote data archives. Perhaps, above all, sensors will need to be highly flexible, easy to install and remove, easy to connect into control networks, and easy to reconfigure for new duties. Sensors used to be something of a Cinderella topic for control systems engineers – a bit of an afterthought and certainly not exciting. However, they are becoming so important that they could change the whole concept of control engineering. n It is hard to escape discussions about the Internet of Things (IoT), Industry 4.0 and machine-to-machine communications. But all the hype and predictions will come to naught if sensor manufacturers don’t rise to the challenges, warns Tony Ingham of Sensor Technology. Sensors will define the future of control systems