TECHNOLOGIES – SENSORS & DATA CAPTURE
Sensors are widely used in everything from consumer electronics to screening bio-chemicals to anti-terrorism – and the UK is a world leader in the technology. Peter Marsh reports
They are the unsung workhorses of the industrial and consumer world, buried inside hundreds of millions of items from ocean monitoring instruments to iPhones. Mainly invisible to all but the technical people producing and installing them, sensors are driving on developments in industries as diverse as agriculture, medical equipment and oil and gas.
Playing a part are several hundred UK manufacturers involved with sensors, either making them or using them to produce bigger and more recognisable pieces of equipment such as analytical instruments or industrial control systems.
Most of the UK sensor companies are small-to-medium sized and are far from household names – a reminder that much of UK manufacturing comprises little known businesses working in niches. However, their clients include many of the world’s industrial giants in sectors such as aerospace, pharmaceu-ticals and automotive. Sensors and the measuring systems that they make possible are key compo-nents in the new digitisation processes becoming more important in ‘IT enabled manufacturing’, or Industry 4.0. Sensors play a big part, for instance, in new developments in robotics, driverless cars and networks of interconnected machines – the so-called Internet of Things.
NEW WAYS TO AUTOMATE PLANT
Among the top companies in UK sensor development is TTP, a manufacturing and consultancy group based near Cambridge. Andrew Baker-Campbell at TTP says: “Many companies are devising new ways to automate their plants – they are trying to combine autonomy and flexibility and reduce the need for labour. As they go down this route they find they need new sensors and sensor systems.”
Baker-Campbell provides as an example TTP’s development of a machine for dicing onions without human intervention, for use in making supermarket ready meals. The equipment is now operating for a food chain that TTP does not want to name.
“Anyone who’s ever peeled an onion in their kitchen knows how many shapes and sizes they come in, plus the variation in the way different layers of skin can be peeled off. To ensure the machine worked effectively, we had to use a lot of different sensors while also developing some complex algorithms,” says Baker-Campbell.
Another company that is a big user of sensors and which counts among its customers many much larger businesses is Blacktrace, which has 125 employees and is based in Royston, Hertfordshire. It is a pioneer in flow chemistry – carrying out complex reactions using tiny amounts of chemicals while the materials are flowing along thin tubes. Keeping track of the reactions can help determine new ways for making industrial products such as catalysts. It can also produce insights into the structure of molecules useful in fields such as medicine or crop protection.
Mark Gilligan, chief executive, says Blacktrace uses in its products “tens if not hundreds” of different sensor systems, many of them developed or adapted to suit the requirements of a customer. “We have a breadth of knowledge from deep physics, maths and chemistry, through to mechanical, electronic and software engineering and are willing to attack pretty much anything [in challenges from customers].”
100 VARIETIES OF SENSOR
According to Sens2B, an online marketing platform for the sensor industry based in France, there are about 100 basic types of sensor. They measure variables that range from the straightforward (such as temperature, velocity or position) to complicated (such as infrared absorption patterns or levels of gamma-radiation). There is likewise a wide spectrum of measure-ment methods, including for instance using lasers to scan moving objects, and monitoring changes in electrical behaviour of specific materials. Sens2B lists 26 industries where sensors have a big role – from shipbuilding to industrial weighing.
Important clusters for sensor development and use are around Cambridge, Oxford, Durham, Harrogate and Edinburgh. Many of the businesses have strong links with university research departments. The enterprises can be divided into three groups depending on their main products: standalone sensors; instruments and measuring equipment; and items such as electronic labels and displays that can be combined with sensors in networks.
In the first category, many UK companies have moved away from simple sensors measuring pressure or capacitance for instance. Such devices are widely available globally and are regarded as commodities. But there are some good example of UK sensor makers with technology that makes them stand out. Banbury-based Sensor Technology has for instance developed a range of innovative torque sensors, such as for measuring the load on cranes.
Silicon Sensing is a joint venture between the US’s United Technologies and Sumitomo Precision Products of Japan. It has one of its two global centres in Plymouth, the other being in Japan. The company has a strong position in so-called MEMS inertial sensors used in positioning, such as in gyroscopes. It has introduced new highly accurate and low-cost MEMS sensors developed in its UK operations. The sensors are seeing use in early versions of driverless cars and in monitoring the position of oil and gas drilling pipelines. Zytronic, with its head office near Newcastle-upon-Tyne, makes devices that monitor changes in electrical behaviour of surfaces. They record very slight movement, and are used in touch-sensitive display screens. In a related field, North Yorkshire-based Peratech has created a way of recording force by measuring changes in electrical resistance in thin films of specialised nano-particles, using an effect known as quantum tunnelling.
Jon Stark, Peratech’s chief executive, says the biggest opportunities lie in smartphones and other connected gadgets. “It’s conceivable that in the next two to three years [our thin films] could be in 50 million – 250 million consumer devices.” In the second category of the UK sensor industry, companies that integrate sensors into larger pieces of equipment include Valeport, a Devon business that is a leader in instruments for the marine industry. The systems do jobs such as measuring sound waves and salinity in water. They are used in industries such as oil and gas, defence and water treatment – partly because of their use in calibrating other devices such as sonar systems for detecting underwater objects.
Matt Quartley, managing director, says many sensors are already so accurate there is “no mileage” in adding to their sensitivity. What really matters, he says, is creating ways to make the best use of the data from the sensors as well as how to combine groups of different sensors in a single instrument.
Paul Maxted of instruments and probe manufacturer Renishaw echoes the point. “In this industry the ‘one size fits all’ approach often isn’t effective. You have to adapt the instrument to meet the requirements of the customer. This means creating different combinations of sensors plus the software to make them work”. Renishaw sells its products to a range of manufac-turing customers for doing jobs such as highly accurately recording the shape of metal parts while they are being machined. Other customers are in shipping and dentistry, where the equipment is used in areas such as monitoring of ships when docking or checking on measurements for new implants. The company has about 900 people working on new developments in measuring systems and sensors – one of the UK’s biggest groups in this field.
Malvern Instruments is a leader in analytical equipment for measuring particle size. The Worcestershire-based business has a strong position in selling to the pharmaceutical industry – a sector which David Higgs, Malvern’s head of marketing, says has recently had to adapt to meet big changes. These include increased competition from makers of cheap generic or ‘me-too’ drugs, and the rise in importance of new processes and products based on biochemistry. The requirement for cutting costs has pushed Malvern into developing a new series of instruments for applications in online process control – a way to make manufacturing more efficient. Also the increased importance of biotechnology has led Malvern to step up its efforts to develop new hardware expressly linked to this field, for instance for protein analysis.
In a related field Sphere Fluidics, based near Cambridge, makes instru-ments for screening large volumes of biochemicals in research applications in the drugs industry. Many of the instruments made by the company use standard sensors called charged coupled devices that it buys from other businesses. The key to Sphere Fluidics’ approach, says Frank Craig, chief executive, is arranging these devices in special configurations to make the machines operate at high accuracy and speed.
In the third key area in the sensor industry, Worcestershire-based Fairfield Labels and DisplayData of Bracknell offer specialised electronic labels that can be used in sensor based networks in environments as diverse as factories and supermarkets. Two Cambridge companies – Flexenable and Pragmatic Printing – produce low-cost displays made by printing electronic circuitry on plastic. The displays can form part of networks in fields such as biometric identification, packaging and electronic games.
Opportunities open up in the Internet of Things
Sensors are playing an increasing role in emerging applications of the Internet of Things – clusters of connected machines and products which require the continual shuttling of data between sensors of and high speed computers. One of the leaders in this field is Cambridge Consultants, a group which works on new technologies in a range of industries.
Simon Jordan, senior physicist at the company, says a key to designing such networked systems is to decide on the “balance of power” between the sensors at the “edge” of the system and the computers or servers at the centre. “The edge [the sensor] is able to decide what matters and what doesn’t, and send only the most relevant information. The centre [the servers] are able to steer the sensors to report different aspects of their environment, and critically, build up a picture of ‘what’s normal’ across thousands of machines. In this way, the sensors form a linked ‘police force’ across the entire user base, reporting on what’s different, what’s changed and what’s unexpected.”
Cambridge Consultants has used this approach in such fields as connecting street lights to central computers. The sensors monitor natural light and weather conditions, so helping to determine the amount of illumination needed, and to stop energy being wasted. A strong competitor in the same field of networks based on street lights is Telensa, part of Cambridge-based consultancy Plextek.
Both SSE and Telensa want to move further into “smart city” systems so that, for example, street lights also house other sensors for jobs such as keeping a watch on parked cars, traffic movement, and pollutants in the atmosphere. In another example of Cambridge Consultants’ work in networked sensors, it has created a special fabric called Xelflex. The textile is lined with fibre optic sensors that send signals to a nearby computer. Clothes made with Xelflex are worn by athletes or people recovering from limb problems. Since the sensors monitor movement, the so-called “smart garments” can help in training or rehabilitation.
Lambert – an automation company in North Yorkshire working in fields such as consumer goods and healthcare – is also developing ideas based on the internet of things. Sales director Matthew Cox says that among the challenges in using these systems in factor concerns cyber security: making sure data do not leak out to competitors or even criminals.
Another example of a networked system is an ambitious set of equipment – based around sensors made by Kromek based in County Durham – that will gradually enter operation in the US over the next few years. The sensors will monitor large cities for the presence of nuclear material – radiological ‘dirty bombs’ for instance – that security chiefs worry could form part of a potentially deadly terrorist threat.
In the networks sensors – measuring small concentrations of gamma rays – will be worn by police officers and other government employees. They will record minute levels of radiation in the atmosphere, raising the alarm if readings suddenly rise without explanation.
Arnab Basu, Kromek chief executive, says the annual global market for sensors of this sort could rise to about $1 billion. He is also looking at how Kromek could use its expertise in networks to move into other fields such as pollution monitoring.