Vibrometric analysis for the MEMS energy harvesting systems developed at IMMS.
Vibrometric analysis for the MEMS energy harvesting systems developed at IMMS.

GreenSense

Enabling technologies for resource- and energy-efficient smart sensor networks

For bio-analysis IMMS developed energy-efficient multi-parametric RFID microsensors and energy harvesting modules for operating autonomous sensors.

The aim of the project was to research and develop a modular technology platform for energy-autonomous smart sensor networks. The sensor networks are intended for use in a wide range of future scenarios, particularly in the monitoring and control of industrial production, transport and operational processes, so that those processes become more energy-efficient and less resource-intensive. The researchers developed hardware solutions for equipment that senses multiple parameters with embedded electronic signal processing, all at low cost and a high level of energy efficiency. Where access is difficult and the cost of the application must be kept to a minimum, energy harvesting solutions have been designed for operating energy-autonomous wireless sensors.

  • Cost- and energy-efficient hardware solutions for multi-parametric RFID microsensors

    IMMS created a new digital CMOS temperature sensor for application in energy-autonomous integrated sensor systems. For this purpose, IMMS developed integrated microelectronic sensor components, manufactured cheaply with CMOS technology and optimal energy saving features, which will measure and provide electronic evaluation of various physical dimensions.

    The new digital CMOS temperature sensor operates across a wide temperature range from –40 °C to 125 °C with high energy efficiency. The accuracy of the sensor is absolute and systematic between –0.1 °C and +0.5 °C.

    The temperature is measured and digitised using only 3.5 μW of electric power, which would facilitate the use of a sensor operable without interruption for at least a 10-year period from a mignon battery with a typical capacity of 1000 mAh.

    On this basis, IMMS designed and created a passive 13.56-MHz RFID multisensor ASIC, which registers, wirelessly, any changes in the temperature and pH of aqueous solutions and can be used for biological analysis.

  • Micromechanical energy harvesting solutions for energy-autonomous operation of wireless sensors

    Energy harvesting is a means whereby systems are supplied with energy from their environment. IMMS has developed micromechancial energy convertors that produce continuous output power at around 10 μW. Such a wattage is enough to supply, for instance, an integrated low-power CMOS temperature sensor which is energy-efficient and provides the signal data for RFID readout. The aim is to convert energy from very low-frequency vibrations such as are created by human movement.

    The basic principle in the system is that of moveable electrostatic comb structures. The main challenge was to achieve low eigenfrequency, capacitance at the highest level possible and a marked change in capacitance when the structures vibrate, all on a tiny chip area. To meet the challenge, IMMS has put into practice a new idea for MEMS harvesters and applied for a patent on the design and electronics, which rely on an out-of-plane oscillator. This name refers to the fact that the central proof mass is in oscillation outside the wafer plane.

    The system architecture for the MEMS energy harvesting module received the Best Paper award at the Analog 2014 conference.

  • Energy-efficient sensor and radio module to set up energy-autonomous wireless sensor networks

    Systems which have a power output of a few microwatts cannot be used for the acquisition and transmission of rapidly changing data and cannot be used to transmit over great distances. A sensor platform in such situations may well require power up to 10 mW.

    With this in mind, IMMS has taken radio sensor nodes and optimised their energy properties so that they can be fully supplied from the environment. Furthermore, an energy simulator was created. It is a solution that constitutes an innovation in the service of circuit design for PCBs, permitting estimation of the electrical consumption of complex microcontroller-based systems before they are combined into the hardware. It also enables the designer to evaluate the energy aspects if peripherals are replaced and the interfaces change. Such details are essential to optimum design of energy-autonomous radio sensor nodes. The modular wireless sensor platform which has been created on this basis can be used for a range of sensors and energy can be harvested from the environment.

    IMMS explored and constructed a variety of circuits for the connection of an electromagnetic harvester. The circuits were given the appropriate dimensions and optimised so as to obtain from the harvester the maximum energy possible. The optimised harvester circuits will function with alternating voltage at the relatively low effective figure of less than 100 mV.

  • CMOS-based sensor technology for the detection of biomarkers

    IMMS has joined forces with IPHT Jena to develop the means whereby epizootic disease can be readily diagnosed. The idea is that a portable electronic device should enable samples from farm stock to be examined for pathogens automatically and rapidly. The affected animals can then be isolated and treated at an early stage, eliminating any risk to consumers, protecting the healthy animals and limiting financial loss.

    The IMMS contribution follows the principles of a diagnostic procedure developed by Jenaer BioChip Initiative (JBCI, IPHT Jena) which has enabled foot and mouth disease (FMD) and other diseases to be detected from samples on glass chips. As the procedure relies on a simple and fast evaluation of the electrical conductivity and optical properties of samples, it can be incorporated into a compact on-site diagnostic system.

    The IMMS contribution follows the principles of a diagnostic procedure developed by Jenaer BioChip Initiative (JBCI, IPHT Jena) which has enabled foot and mouth disease (FMD) and other diseases to be detected from samples on glass chips. As the procedure relies on a simple and fast evaluation of the electrical conductivity and optical properties of samples, it can be incorporated into a compact on-site diagnostic system.

    The microelectronic approach offers additional measurement options as an alternative to the original glass plate-based platform. The aim is to use the new devices to keep track on the reactions taking place during diagnosis and to unify the three types of measurement on a single semiconductor biochip.

  • Funding

    The GreenSense project has been funded by the “Land” of Thüringen (Ministry of Economics, Labour and Technology) and the European Social Fund (ESF) under the reference 2011 FGR 0121.

Duration

2012 – 2014

Reference

2011 FGR 0121