In the 21st century the majority of industrial enterprises, starting from giant world corporations and finishing with local manufactures, aspire to make their businesses more efficient, secure and economically profitable. Modern requirements of economy can only be satisfied with innovative intelligent systems which are actively developed thanks to the progress of Industry 4.0. Scientists of South Ural State University are “at the cutting edge” of this relevant global trend. Research is conducted for strategically important industry branches: atomic, aerospace, petrochemical, and many others, in cooperation with the world’s industrial giants and with the University of Oxford.
The concept “intelligent sensor” is more frequently used for defining sensors of new generation which use modern computational possibilities and more complex algorithms of data processing allowing to improve their functional characteristics. In 2009, a new national standard, which clearly defined the concept of intelligent sensor as a device which possesses the function of metrological self-validating, came into force in Russia.
“This means that unlike all the other devices, it is the measuring device exactly that possesses such characteristic as error. Operability of this device is considered from the perspective of metrological accuracy. If sensor’s error does not exceed the allowable limits, this sensor is considered as metrologically accurate,” explains Oleg Bushuev, candidate of engineering sciences, associate professor of the Informational and Measuring Technology Department of the SUSU School of Electrical Engineering and Computer Science.
During 7 years Oleg Bushuev has been conducting research in the field of “intelligent sensors” in collaboration with a professor of Oxford University – Manus Patrick Henry. Doctor Henry is the world’s leading specialist in the field of processing of signals, computational equipment and self-diagnostics.
The task of creating the intelligent sensor is being complicated by the fact that a sensor can only be considered intelligent in case of possessing certain algorithms for automated self-validating and checking of current error. If South Ural scientists manage to implement this functional in a device, a very important problem (economic problem as well) – the increase of calibration interval - will become possible to solve. Some devices can’t be calibrated without disassembling, therefore ideally the intelligent sensor itself should set an algorithm according to which it would be possible to determine if a device is operable or not.
“This conception in systematic form was consistently described in proceedings of staff of Oxford University in the early 90-ies,” continues Oleg Yuryevich. “Professor Manus Henry is the author of a concept which in Western literature is called ‘Self-validation’ or ‘Self-Validating Sensor’ (SEVA Sensor); in Russian it means self-verifying or self-validating sensor. The point is, it checks if a sensor lost its functional from the perspective of metrology. Intelligent sensor should be able to “say” what is wrong with it before any problem occurs.”
It is quite hard to implement in practice, as there are too many devices, as well as implementation variants. The idea of Doctor Henry is in determining the possible reasons of malfunctioning and sources of error, for example, of a Coriolis flowmeter. He proposes a new, more improved construction which would allow avoiding defects. The research will allow providing error-free performance of a sensor if there is pipe’s vibration, and also a long service life and simplicity of the flowmeter use. Besides, this device will provide high accuracy of mass flow measurement. The idea of improving devices goes along with the idea of self-validating, and we can say that this is the same task just formulated differently.
“At SUSU scientists are working over improving domestic Coriolis flowmeters independently from Oxford. We are performing a certain part of tasks in order to create intelligent sensors. This process sonsists of many steps: before working with the completed device we must check a lot of hypotheses, for example, which characteristics of technologic process influence on signal’s parameters, or which signals we can use for our purposes. This requires different type of experiments,” says Oleg Bushuev.
Scientists of South Ural State University are conducting research in the field of pressure sensors. They created a new perspective construction of pressure sensor, which does possess the self-validating function; it means that inside of an ordinary pressure transducer the possibility to excitation of this construction with test signals - with the use of ultrasound – is stipulated. Characteristics of these signals are assessed by different mathematical methods, one of them is the method proposed by Doctor Manus Henry and called PRISM.
“Our idea is connected with creating an intelligent pressure sensor and using the PRISM method (as one of the possible) for signals processing,” says Oleg Bushuev. “The task is interesting for Manus Henry because our pressure sensor's signals are short-time which complicates the process of their parameters’ assessment. Doctor Henry had to modify his method so that it could become applicable to our signals; that was the main difficulty, but we overcame it.”
Results of the collaborative work of South Ural scientists and scientists from the University of Oxford were presented at the 26th International Symposium on Industrial Electronics (ISIE) IEEE Conference in Edinburgh and soon are going to be published in the high-ranked scientific journal Industrial Electronics Magazine. Besides, Manus Henry is the Head of the SUSU International Laboratory for Self-Monitoring and Self-Validating sensors and Systems, which allows us counting on further successful cooperation between Oxford University and SUSU. Scientists are planning on collaborative development of perspective ideas; in particular, they are considering the possibility of working over a project of Rosatom national corporation for creation of intelligent temperature sensors.