ACOUSMONSYS: Integrated Acoustic Emissions Sensor with an Innovative Monitoring System

Recent developments in sensing technology, microprocessors, and miniaturised radio transceivers has enabled a new generation of Wireless Sensors Networks. The future of these sensors is to have an ubiquitous sensing nodes that will autonomously report on operating conditions, and that this data will be used to facilitate structural health monitoring, embedded test & evaluation, and condition based maintenance of critical industrial rotating machinery without the use of expensive cabling. In addition, in order to provide sensing networks which are truly autonomous, chemical batteries must be eliminated from the sensor and some kind of energy harvesting has to be foreseen. Piezoelectric materials have demonstrated their ability to convert vibration energy from vibrating machinery and rotating structures into electrical energy for powering a wireless sensing node. Hence, an acoustic emission self-powered wireless sensor is one of the main objectives to be achieved in this project. The sensor will measure using frequency as opposed to time which is an advancement from the state of the art.

General operation of the foreseen sensor is as follows:
• The sensor will be powered by harvesting energy of the very machine (rotating vibrations, in principle, but also by electromagnetic coupling if necessary).
• Various AE transducers will collect high frequency info/data, with different frequency ranges between 50kHz - 500kHz, and they will process data in time and frequency.
• The local CPU will extract fault conditions from the info received, and will compare them to thresholds, pre-programmed in sensor initialisation from a PC running a specific software application.
• If the threshold is exceeded, the system will wirelessly send an alarm to the remote Central, with basic information about the fault detected.
• Prediction of available life left in the machine before failure will also be a feature of this project.

THe project will be broken down into the following areas:

 

Product Definition

where we will define the application field and the case study for validating the technology. We will have delieverables of defining the Market demand and determining the functional specifications and defining the system specifications.

Fault Condition Characterisation and Acoustic Signal Response

To study the Acoustic Spectral Response for every defined material and fault where the outcomes will look to setup of field instrumentation and to model Fault condition

Sensor Prototype and Laboratory Validation

where we will design and calculate electronic circuits for the sensor, including acoustic transducer and signal processing, processor, interfaces, communications and power harvesting modules

Communications Network and Expert System

where we will integrate the system and finally validate it in industry applications.

General operation of the foreseen sensor is as follows:
• The sensor will be powered by harvesting energy of the very machine (rotating vibrations, in principle, but also by electromagnetic coupling if necessary).
• Various AE transducers will collect high frequency info/data, with different frequency ranges , and they will process data in time and frequency.
• The local CPU will extract fault conditions from the info received, and will compare them to thresholds, pre-programmed in sensor initialisation from a PC running a specific software application.
• If the threshold is exceeded, the system will wirelessly send an alarm to the remote Central, with basic information about the fault detected.
• Prediction of available life left in the machine before failure will also be a feature of this project.

Sensors
harvesting
acoustic
fuzzy logic
CPU

Current Project Partners:

RTDs:

1) CTM Spain: Project Leader, fault condition characterisation of the materials will test and advise laboratory validation of the developed sensors. Mechanical characterisation and participate in the industrial validation of the developed sensors. Testing of prototypes.

2) UPC Spain: Key Role in the product definition, development of the sensors, prototyping and the integration of the technology



SMEs

1) SME Spain: 1st level SME end user company, involved in the definition of the product, the communications network and expert system. The technology will be fitted to the machines they produce to be tested and adjusted. This company produces rotating machines and therefore will test the new sensor on these rotating machines.

2) SME United Kingdom: Is an SME specialised in engineering and non-destructive testing by acoustic emission. They will work on fault condition characterization and acoustic signal response.

3) SME France: SME specialised in the supply of sensors and equipment for instrumentation. They will be involved in product definition, development of the solution and integration of the technology in order to fine tune the technology.

4) SME Estonia: an SME that has experience in wireless sensor systems using ZigBee and would be able to test sensor communications networks for the new Acoustic Emission Sensor.