SMARTER: Smart Multifunctional ARchitecture & Technology for Energy aware wireless sensoRs

Lead Research Organisation: UNIVERSITY OF EXETER
Department Name: Engineering Computer Science and Maths

Abstract

The overall vision of the project is to develop comprehensive knowledge and an innovative methodology in the areas of energy autonomous wireless systems from a global system perspective, enabling self-powered, battery-free wireless sensing nodes to meet a wide range of structural health monitoring (SHM) applications. The research vision builds on the project partners' complementary skills and strengths in the area of 'towards zero -power ICT' with the potential to lead to multiple scientific and technical breakthroughs. The first breakthrough is to make use of the SHM sensing device itself to implement a single multifunctional device providing both structural health data and electrical energy harvested from mechanical vibrations. Another breakthrough will be to store the harvested energy in a fully integrated smart storage device, which adapts its storage capacity, according to the available energy in the environment and to the power consumption of the load. This adaptability will provide a constantly optimized matching between storage device and energy harvester to foster energy transfer. The energy storage itself will be a micro-ultracapacitor, so will have the desirable features of high specific energy, short time response, long lifetime and safe operation. This micro -ultracapacitor will be implemented in a silicon compatible technology so as to facilitate co-integration with other functions. Moreover, to drastically reduce the power consumption of the communication module, the proposed strategy is based on using impulse radio UWB (ultra-wideband) and dark silicon design approaches. A final innovation will be the co-location of the different devices (harvesting, sensing, storage, processing, data transmission) on the same flexible substrate, in order to enable conformal attachment of the device, a characteristic highly desirable in a SHM context wher e the surfaces to be monitored are seldom planar. Additionally, by this means the issue of the anisotropy of vibration harvesters is settled, the harvester being, by nature, properly oriented. More globally, the project aims at producing a device in which co-integration, co-location of functions, versatility of applications and energy autonomy are pushed to a maximum.

Planned Impact

This research will make breakthroughs in the fields of power harvesting and power storage and will lead to a decrease in power consumption so ena bling battery-free wireless sensing nodes for a range of applications. There are no other research projects within the EU academic community which have the scope of this multi-breakthrough multidisciplinary research which encompasses multifunctional sensing and energy harvesting, energy storage, power management wireless communication technologies, computing with flexible and intelligent energy flow control for minimization of energy consumption and multiphysical modelling and an optimisation framework to support vertical system integration.

It is expected that the scientific research will significantly lead to a comprehensive understanding and developments-ranging from
- macro and nano-scaled component and sub-system to system architecture design and integration,
- hardware and software to integrated software approaches,
- and system demonstration for future transfer of the technologies to industry.

These developments will ultimately increase the harvested and stored energy and reduce the power consumption of ICT and enable the emergence of innovative, scalable and reliable energy technology and progression towards zero power ICT.

The developed enabling technology will provide self -sufficiency in energy supply for monitoring of structural health conditions and is potentially suitable for a wide range of industrial applications in structural health monitoring, including those in the aerospace aviation & defence, automotive & transport industries and on such structures as wind turbines for renewable ener gy, water, oil and gas pipe-lines, and civil bridge and tunnel infrastructures. Potential markets include wireless sensors, process controls and consumer devices. The global market for energy harvesting could grow to $4.4 billion by 2020 and the EU has the capability in sensors and instrumentation, electronics, and design to exploit these technologies.

The potential benefits of the technology for stakeholders are:
1 No need for batteries and so no need to replace batteries
2 No need for cabling to mains
3Truly "Fit-and-Forget"
4 Reduce costs and time in installation, replacement and maintenance

Publications

10 25 50
 
Description We have developed two key technologies ( energy-aware architecture and low power consumption power management module) from the project.
Exploitation Route Yes, to the end of users
Sectors Aerospace

Defence and Marine

Digital/Communication/Information Technologies (including Software)

Education

Electronics

Energy

Manufacturing

including Industrial Biotechology

Transport

 
Description A number of peer reviewed journal papers with high impact factors and international conference papers have been published and submitted with open access. A technology demonstration event has been demonstrated in May 2016, having showcase to academic and industry. Spin out from the university of Exeter
First Year Of Impact 2021
Sector Aerospace, Defence and Marine,Digital/Communication/Information Technologies (including Software),Electronics,Energy,Manufacturing, including Industrial Biotechology,Transport
Impact Types Economic

 
Description EPSRC
Amount £64,000 (GBP)
Organisation Engineering and Physical Sciences Research Council (EPSRC) 
Sector Public
Country United Kingdom
Start 08/2017 
 
Description Energy harvesting enabling system for applications
Amount £64,750 (GBP)
Organisation Engineering and Physical Sciences Research Council (EPSRC) 
Sector Public
Country United Kingdom
Start 03/2016 
End 10/2019
 
Description Intitial GW4 funding for energy harvesting
Amount £2,500 (GBP)
Organisation GW4 
Sector Academic/University
Country United Kingdom
Start 04/2014 
End 07/2014
 
Description SENTIENT - SENsors To Inform &Enable wireless NeTworks
Amount £144,049 (GBP)
Funding ID 101657 
Organisation TSB Bank plc 
Sector Private
Country United Kingdom
Start 01/2014 
End 12/2016
 
Description Unlocking the science for an Autonomous Structural Health Monitoring System
Amount £17,000 (GBP)
Organisation GW4 
Sector Academic/University
Country United Kingdom
Start 11/2014 
End 05/2015
 
Description Wide bandwidth energy harvesting for applications
Amount £64,750 (GBP)
Organisation University of Leeds 
Department Faculty of Engineering
Sector Academic/University
Country United Kingdom
Start 08/2016 
End 04/2020
 
Title Energy-aware Approaches for Energy Harvesting Powered Wireless Sensor Nodes 
Description Intensive research on energy harvesting powered wireless sensor nodes (WSNs) has been driven by the needs of reducing the power consumption by the WSNs and the increasing the power generated by energy harvesters. The mismatch between the energy generated by the harvesters and the energy demanded by the WSNs is always a bottleneck as the ambient environmental energy is limited and time-varying. This paper introduces a combined energy-aware interface (EAI) with an energy-aware program to deal with the mismatch through managing the energy flow from the energy storage capacitor to the WSNs. 
Type Of Material Improvements to research infrastructure 
Provided To Others? No  
Impact These two energy-aware approaches were implemented in a custom developed vibration energy harvesting powered WSN. The experimental results show that, with the 3.2 mW power generated by a piezoelectric energy harvester (PEH) under an emulated aircraft wing strain loading of 600 µe at 10 Hz, the combined energy-aware approaches enable the WSN to have a significantly reduced sleep current from 28.3 µA of a commercial WSN to 0.95 µA and enable the WSN operations for a long active time of about 1.15 s in every 7.79 s to sample and transmit a large number of data (388 bytes), rather than a few ten milliseconds and a few bytes, as demanded by vibration measurement. When the approach was not used, the same amount of energy harvested was not able to power the WSN to start, not mentioning to enabling the WSN operation, which highlighted the importance and the value of the energy-aware approaches in enabling energy harvesting powered WSN operation successfully. 
 
Title Micropower Circuit for Maximum Power Transfer Using Direct VOC/2 Finding Method for Piezoelectric Energy Harvesting 
Description A novel implementation method of maximum power transfer for piezoelectric energy harvesters (PEHs) connected to a rectifier with a smoothing capacitor at the rectifier output is presented based on the half open-circuit voltage (VOC/2) of a rectified PEH by exploiting the RC response of a circuit formed by the PEH, rectifier, and smoothing capacitor. The presented technique has a specifically designed high-pass filter which has a peak output voltage that corresponds to the VOC/2 of the PEH, which is also the voltage when maximum power transfer occurs in that circuit configuration. The control circuit filters and differentiates the voltage across the smoothing capacitor to directly determine the timing of reaching the VOC/2 of the PEH without having to find the VOC first, and is fully implemented using discrete analog components without the need of a programmable controller, leading to low power consumption of the method. The control circuit is used in conjunction with a full wave diode bridge rectifier and a DC-DC converter to harvest energy from a macro-fiber composite (MFC) PEH. The MFC was subjected to various strain levels at low frequencies from 2 to 10 Hz. Experimental results show that the implemented circuit is adaptive to various vibration amplitudes and frequencies and has a maximum power transfer efficiency of up to 98.28% with power consumption as low as 5.16 µW 
Type Of Material Computer model/algorithm 
Year Produced 2016 
Provided To Others? Yes  
Impact Have been disseminated to UK Energy Harvesting Network, IEEE Sensors 2016 Conference 
 
Title Strain Energy Harvesting Powered Wireless Sensor System Using Adaptive and Energy-Aware Interface for Enhanced Performance 
Description This paper presents a wireless sensor system (WSS) powered by a strain energy harvester (SEH) through the introduction of an adaptive and energy-aware interface for enhanced performance under variable vibration conditions. The interface is realized by an adaptive power management module (PMM) for maximum power transfer under different loading conditions and an energy-aware interface (EAI) which manages the energy flow from the storage capacitor to the WSS for dealing with the mismatch between energy demanded and energy harvested. The focus is to realize high harvested power and high efficiency of the system under variable vibration conditions, and an aircraft wing structure is taken as a study scenario. The SEH powered WSS was tested under different peak-to-peak strain loadings from 300 to 600 µe and vibrational frequencies from 2 to 10 Hz to verify the system performance on energy generation and distribution, system efficiency, and capability of powering a custom-developed WSS. Comparative studies of using different circuit configurations with and without the interface were also performed to verify the advantages of the introduced interface. Experimental results showed that under the applied loading of 600 µe at 10 Hz, the SEH generates 0.5 mW of power without the interface while having around 670 % increase to 3.38 mW with the interface, which highlights the value of the interface. The implemented system has an overall efficiency of 70 to 80 %, a long active time of more than 1 s, and duty cycle of up to 11 % for vibration measurement under all the tested conditions. 
Type Of Material Data analysis technique 
Year Produced 2014 
Provided To Others? Yes  
Impact Has been disseminated to the UK Energy Harvesting Network, EURO Sensors 2016 
 
Description EN-Come 
Organisation BAE Systems
Department BAE Systems Avionics
Country United Kingdom 
Sector Private 
PI Contribution My research group are taking a leadership role to develop the energy harvesting powered system using integrated smart Composite Structures and energy-aware architecture to enable dealing with mismatch of energy harvested and energy demanded.
Collaborator Contribution Industry supplied the system requirement and technical assessment to the progress.
Impact on-going
Start Year 2014
 
Description EN-Come 
Organisation BAE Systems
Department BAE Systems Military Air & Information
Country United Kingdom 
Sector Private 
PI Contribution My research group are taking a leadership role to develop the energy harvesting powered system using integrated smart Composite Structures and energy-aware architecture to enable dealing with mismatch of energy harvested and energy demanded.
Collaborator Contribution Industry supplied the system requirement and technical assessment to the progress.
Impact on-going
Start Year 2014
 
Description EN-Come 
Organisation Lancaster University
Country United Kingdom 
Sector Academic/University 
PI Contribution My research group are taking a leadership role to develop the energy harvesting powered system using integrated smart Composite Structures and energy-aware architecture to enable dealing with mismatch of energy harvested and energy demanded.
Collaborator Contribution Industry supplied the system requirement and technical assessment to the progress.
Impact on-going
Start Year 2014
 
Description EN-Come 
Organisation University of Central Lancashire
Country United Kingdom 
Sector Academic/University 
PI Contribution My research group are taking a leadership role to develop the energy harvesting powered system using integrated smart Composite Structures and energy-aware architecture to enable dealing with mismatch of energy harvested and energy demanded.
Collaborator Contribution Industry supplied the system requirement and technical assessment to the progress.
Impact on-going
Start Year 2014
 
Description EN-Come 
Organisation ZF Automotive UK Limited
Department Conekt
Country United Kingdom 
Sector Private 
PI Contribution My research group are taking a leadership role to develop the energy harvesting powered system using integrated smart Composite Structures and energy-aware architecture to enable dealing with mismatch of energy harvested and energy demanded.
Collaborator Contribution Industry supplied the system requirement and technical assessment to the progress.
Impact on-going
Start Year 2014
 
Description SMARTER 
Organisation University of Barcelona
Department Psychiatry Barcelona
Country Spain 
Sector Academic/University 
PI Contribution we have developed the following items for the collaboration for the SMARTER project: 1. an integrated piezoelectric energy harvester onto carbon fibre composite materials 2. fully analogue microwatt power consumption power management circuit for efficient energy harvesting 3. energy-aware interface for integrating of energy harvesting and wireless sensor nodes. 4. fully integrated energy harvesting powered wireless sensor nodes for aero-craft industrial application
Collaborator Contribution University of Toulouse, LAAS-CNRS has developed super-capacitor for energy storage in the system. University of Barcelona has developed a power management for the system.
Impact This is a multi-disciplinary research collaboration, encompassing materials, physics, mechanical, electrical and electronic engineering, and information and communication technology with an "integrated system approach. We have developed ground breaking circuitry and integration to meet key challenges in energy harvesting for applications.
Start Year 2012
 
Description SMARTER 
Organisation University of Toulouse
Department Laboratory for Analysis and Architecture of Systems
Country France 
Sector Academic/University 
PI Contribution we have developed the following items for the collaboration for the SMARTER project: 1. an integrated piezoelectric energy harvester onto carbon fibre composite materials 2. fully analogue microwatt power consumption power management circuit for efficient energy harvesting 3. energy-aware interface for integrating of energy harvesting and wireless sensor nodes. 4. fully integrated energy harvesting powered wireless sensor nodes for aero-craft industrial application
Collaborator Contribution University of Toulouse, LAAS-CNRS has developed super-capacitor for energy storage in the system. University of Barcelona has developed a power management for the system.
Impact This is a multi-disciplinary research collaboration, encompassing materials, physics, mechanical, electrical and electronic engineering, and information and communication technology with an "integrated system approach. We have developed ground breaking circuitry and integration to meet key challenges in energy harvesting for applications.
Start Year 2012
 
Title METHOD OF CONTROLLING AN ENERGY HARVESTING SYSTEM 
Description A method of controlling an energy harvesting system, comprising providing an energy storage device (121) and a plurality of energy harvesters (111); wherein each of the energy harvesters (111) is connectable to the energy storage device (121) thereby to transfer energy to the energy storage device (121); determining a load characteristic of an energy harvester (111); and controlling a transfer of energy from the energy harvester (111) to the energy storage device (121) in dependence on the determined load characteristic. 
IP Reference WO2018220406 
Protection Patent application published
Year Protection Granted 2018
Licensed Commercial In Confidence
Impact Looking for investors
 
Title Energy-aware Approaches for Energy Harvesting Powered Wireless Sensor Nodes 
Description Intensive research on energy harvesting powered wireless sensor nodes (WSNs) has been driven by the needs of reducing the power consumption by the WSNs and the increasing the power generated by energy harvesters. The mismatch between the energy generated by the harvesters and the energy demanded by the WSNs is always a bottleneck as the ambient environmental energy is limited and time-varying. This paper introduces a combined energy-aware interface (EAI) with an energy-aware program to deal with the mismatch through managing the energy flow from the energy storage capacitor to the WSNs. These two energy-aware approaches were implemented in a custom developed vibration energy harvesting powered WSN. The experimental results show that, with the 3.2 mW power generated by a piezoelectric energy harvester (PEH) under an emulated aircraft wing strain loading of 600 µe at 10 Hz, the combined energy-aware approaches enable the WSN to have a significantly reduced sleep current from 28.3 µA of a commercial WSN to 0.95 µA and enable the WSN operations for a long active time of about 1.15 s in every 7.79 s to sample and transmit a large number of data (388 bytes), rather than a few ten milliseconds and a few bytes, as demanded by vibration measurement. When the approach was not used, the same amount of energy harvested was not able to power the WSN to start, not mentioning to enabling the WSN operation, which highlighted the importance and the value of the energy-aware approaches in enabling energy harvesting powered WSN operation successfully. 
Type Of Technology New/Improved Technique/Technology 
Year Produced 2015 
Impact Published in IEEE Sensors Journal 2017 
 
Title Knee-joint Energy Harvester Powering a Wireless Communication Sensing Node 
Description Human-based energy harvesters are attractive as sustainable replacements for batteries to power wearable or implantable devices and body sensor networks. In the work presented here, a knee-joint energy harvester (KEH) was introduced to power a customer-built wireless communication sensing node (WCSN). The KEH used a mechanical plucking technique to provide sufficient frequency up-conversion - from a few Hz to the resonant frequency of the KEH - so as to generate the high power required. It was actuated by a knee-joint simulator, which reproduced the knee-joint motion of human gaits at a walking frequency of 0.9 Hz. The energy generated was first stored in a reservoir capacitor and then released to the WCSN in a burst mode with the help of an energy aware interface (EAI). The WCSN was deployed with a 3-axis accelerometer, a temperature sensor, and a light detector for data sensing. A Jennic microcontroller was utilised to collect and transmit the measured data to a base station placed at a distance of 12 m. The energy generation by the KEH and the energy distribution in the system was characterised in real time by an in-house-built set-up. The results showed that the KEH generated an average power output of 1.76 mW when powering the WCSN. After charging the reservoir capacitor for 28.4 s, the KEH can power the WCSN for a 46 ms period every 1.25 s. The results also clearly illustrated how the energy generated by the KEH was distributed in the system and highlighted the importance of using a high performance power management approach to improve the performance of the whole system. 
Type Of Technology Systems, Materials & Instrumental Engineering 
Year Produced 2015 
Impact Published In Smart Materials and Structures 
 
Title Micropower Circuit for Maximum Power Transfer Using Direct VOC/2 Finding Method in Piezoelectric Energy Harvesting 
Description A novel implementation method of maximum power transfer for piezoelectric energy harvesters (PEHs) connected to a rectifier with a smoothing capacitor at the rectifier output is presented based on the half open-circuit voltage (VOC/2) of a rectified PEH by exploiting the RC response of a circuit formed by the PEH, rectifier, and smoothing capacitor. The presented technique has a specifically designed high-pass filter which has a peak output voltage that corresponds to the VOC/2 of the PEH, which is also the voltage when maximum power transfer occurs in that circuit configuration. The control circuit filters and differentiates the voltage across the smoothing capacitor to directly determine the timing of reaching the VOC/2 of the PEH without having to find the VOC first, and is fully implemented using discrete analog components without the need of a programmable controller, leading to low power consumption of the method. The control circuit is used in conjunction with a full wave diode bridge rectifier and a DC-DC converter to harvest energy from a macro-fiber composite (MFC) PEH. The MFC was subjected to various strain levels at low frequencies from 2 to 10 Hz. Experimental results show that the implemented circuit is adaptive to various vibration amplitudes and frequencies and has a maximum power transfer efficiency of up to 98.28% with power consumption as low as 5.16 µW. 
Type Of Technology Systems, Materials & Instrumental Engineering 
Year Produced 2017 
Impact It will be published in IEEE Transaction of Industrial Circuits in 2017 ( High impact Journal) 
 
Title Single Piezoelectric Transducer as Strain Sensor and Energy Harvester Using Time-multiplexing Operation 
Description This paper presents a single piece of macro-fiber composite (MFC) piezoelectric transducer as a multifunctional device of both strain sensor and energy harvester for the first time in the context of an energy harvesting powered wireless sensing system. The multifunction device is implemented via time-multiplexing operation for alternating strain sensing and energy harvesting functions at different time slots associated with different energy levels, that is, when there is insufficient energy harvested in the energy storage for powering the system, the MFC is used as an energy harvester for charging up the storage capacitor; otherwise, the harvested energy is used for powering the system and the MFC is used as a strain sensor for measuring structural strain. A circuit is designed and implemented to manage the single piece of MFC as the multifunctional device in a time-multiplexing manner, and the operation is validated by experimental results. The strains measured by the MFC agree well with a commercial strain sensor of extensometer and therefore, the studied method can be potentially used for autonomous structural health monitoring of strain. 
Type Of Technology Systems, Materials & Instrumental Engineering 
Year Produced 2015 
Impact This work has been disseminated to IEEE Sensors and accepted by IEEE Transaction of Industrial Circuits (high impact factor) 
 
Title Strain Energy Harvesting Powered Wireless Sensor System Using Adaptive and Energy-Aware Interface for Enhanced Performance 
Description This paper presents a wireless sensor system (WSS) powered by a strain energy harvester (SEH) through the introduction of an adaptive and energy-aware interface for enhanced performance under variable vibration conditions. The interface is realized by an adaptive power management module (PMM) for maximum power transfer under different loading conditions and an energy-aware interface (EAI) which manages the energy flow from the storage capacitor to the WSS for dealing with the mismatch between energy demanded and energy harvested. The focus is to realize high harvested power and high efficiency of the system under variable vibration conditions, and an aircraft wing structure is taken as a study scenario. The SEH powered WSS was tested under different peak-to-peak strain loadings from 300 to 600 µe and vibrational frequencies from 2 to 10 Hz to verify the system performance on energy generation and distribution, system efficiency, and capability of powering a custom-developed WSS. Comparative studies of using different circuit configurations with and without the interface were also performed to verify the advantages of the introduced interface. Experimental results showed that under the applied loading of 600 µe at 10 Hz, the SEH generates 0.5 mW of power without the interface while having around 670 % increase to 3.38 mW with the interface, which highlights the value of the interface. The implemented system has an overall efficiency of 70 to 80 %, a long active time of more than 1 s, and duty cycle of up to 11 % for vibration measurement under all the tested conditions. 
Type Of Technology Systems, Materials & Instrumental Engineering 
Year Produced 2016 
Impact Has been disseminated to Euro Sensors 2016 Conference 
 
Company Name Encortec 
Description Encortec develops Vibration Energy Harvesting Sensors for businesses. 
Year Established 2021 
Impact We deliver high-performance energy harvesting powered sensor system technology, products and data services in time-rich and data-rich monitoring that drive positive change at scale, achieving sustainability, productivity, and prosperity for industrial digitalisation.
Website https://encortecsystems.com/
 
Description 4 Papers published in the IEEE Sensors Conference 2016 
Form Of Engagement Activity A broadcast e.g. TV/radio/film/podcast (other than news/press)
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Promotion of energy harvesting research in energy harvesting and attract attentions from the world.
Year(s) Of Engagement Activity 2016
 
Description High Performance Energy Harvesting Technology Demonstration Event to Industry 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Industry/Business
Results and Impact Around 20 industry delegates from AirBus, BAE Systems and DSTL and others attended with presentations and 3 live technology demonstrators.
Year(s) Of Engagement Activity 2016
URL http://emps.exeter.ac.uk/engineering/research/structures-dynamics/energyharvesting/newsandevents/
 
Description My Group has attended the UK Energy Harvesting Workshop held in 2016. I had invited a presetation. 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Professional Practitioners
Results and Impact Promotion of Exeter Research in Energy Harvesting
Year(s) Of Engagement Activity 2016