Vladimir Milosavljevic

Miniature low cost electrochemical sensor module for measurement of gas concentration

This paper describes miniature low cost sensor module for measurement of gas concentration. The aim of this paper is to explain how to make a miniature module with low power consumption and low cost, which can be used for many types of electrochemical gas sensors without major hardware changes. Device is based on AVR ATmega8 microcontroller. As signal processing circuit a specialized integrated circuit LMP91000 configurable via I2C interface is used. All parameters are saved in EEPROM memory. For communication with master device RS-485 interface is used. In application, after power up, sensor device reads parameters from memory and configure the circuit for signal processing, than the sensor is ready to sends data upon master device request. Master device can change any parameter at any time. The designed sensor module costs less than 10 Euros and consumption less than 4 mA, which is in the idle mode is reduced to about 1mA.

Application of GPRS modules in data acquisition and control of devices for air quality monitoring

This paper describes a modern GPRS based system for air pollution monitoring. Due to the widespread of the mobile telephony, currently it is possible to use GPRS modules for wireless data acquisition and control. At the moment, there are a lot of available solutions with usage of GPRS modems and some of them are mentioned in this paper as reference to our design. Explanations of how to use GPRS modem with common problems and solution are given. Designed prototype system consists of Telit GM862 GPRS modem, dsPIC30F4013 microcontroller and set of metal-semiconductor gas sensors with accompanying processing electronic. Integration of microcontroller inside sensing process allows automatic monitoring and support for management of the peripherals units. This system measures concentrations of gases such as CO, CO2, NH3, CH4 and H2S. For gas sensor compensation, sensors for humidity, pressure and temperature are installed.

Energy harvesting wireless sensor node for monitoring of surface water

Monitoring of surface water areas before, during and after the flood is important to collect useful information for future risk assessment and for the purpose of learning about future preventive measures. This paper describes the development of the wireless sensor network (WSN) node capable of collecting water level measurement data on remote locations that are covered by surface waters, either by flooding or seasonal environmental impacts. Our main goal was to create a flexible, easy-to-deploy and easy-to-maintain, adaptable, low-cost and low power WSN node for monitoring of water level. Measuring node is based on the ultra low power components, with the most important MSP430 series microcontroller and radio frequency (RF) module based on nRFf24l01+ integrated circuit. Each node contains energy harvesting subsystem and supercapacitor for energy storage. Water level measurement is performed by a separate module, which is based on PIC12F1822 microcontroller that supports small capacitance measurements. Water level measurement results for different situations were collected, analyzed and graphically presented.

Modular WSN node for environmental monitoring with energy harvesting support

Environmental protection is one of the most challenging tasks for humanity. All of the latest technologies to certain extent are applied in this area, among others, wireless sensor networks as well. In this paper a wireless sensor node designed specifically for monitoring of environmental parameters is described. The main advantage of this node is the use of energy harvesting techniques and supercapacitor as power supply method. The absence of batteries affects the reduction of maintenance costs and environmental impact. The paper shows that combination of energy harvesting and supercapacitor represents a sustainable solution of constant power supply of wireless sensor network node.

Methods of environmental monitoring parameters based on smart measurement systems

As the effects of global warming are spreading globally, the world population encounters one of the most important social and scientific phenomena-changing the parameters of the environment due to pollution. Any conducted action requires precise and accurate measuring of the environmental parameters at several dozens of thousands points deployed around the world. Since financially, as well as practically, it is impossible to create such a large number of measuring stations which would network all over the planet, it is obvious that some alternative solutions must be found. A new measuring system is developed and measuring methods for remote measurement of environmental parameters are implemented. This system can be implemented as a stationary or mobile measuring station. The working hypothesis is based on the use of statistical analysis of measurement data. It leads to the possibility of reducing the number of sensors at measure station, as based on the monitoring of one value-gas concentration (the concentration of carbon monoxide) can be estimated values of other gas (the concentration of nitrogen — dioxide) in the case that they originate from the same source. Using prediction and regression models — interpolation and extrapolation have shown the possibility to reduce the number of measuring stations. Also, based on a mathematical model (ARMA) estimation of concentrations of gases based on previous measurements is shown.

Implementation of wearable energy harvesting wireless sensor node using ink-jet printing on flexible substrate

Specific requirements in the design of modern electronic devices have increased popularity of flexible printed circuits. In recent years, with the application of new materials and their printing on a flexible substrate, a large number of new flexible sensors have been developed. In this paper, the implementation of a device made by ink-jet printing on a flexible substrate is described. Fully flexible prototype is composed of sensors, microcontroller, wireless communication and energy harvesting power supply, which is suitable for wearable applications. Ultra-low-power microcontroller is used for reading data from sensors and for managing short range wireless communication. Supercapacitor and energy harvesting from photovoltaic cell are used to power device. The designed prototype is mounted on the back side of solar panel, which is also flexible. The paper describes the procedures used in design process and gives basic explanation of electronic subsystems. The first prototype proved to be a functional solution and can be efficiently used in applications with flexible sensors.

Remote environmental monitoring system for application in industry and landfill sites

This paper describes a modern system for measuring the concentration of gases. Industrial processes can be a source of pollution and population should be promptly informed of any change in the concentration of harmful gases. Unlike industry, gases that are produced in landfills is impossible to avoid due to natural processes and general tendency is to use gas emissions as an energy source (natural gas) or converted into harmless compounds by combustion. The system is suitable for use in terrain conditions and operating on battery or solar power. Electrochemical and infrared sensors are built into the system because of low power consumption and an extended measurement range. The accuracy of the measurements is satisfactory, with fast response and generally good selectivity to the target gases. Signals from set of sensors are processed in local microprocessor unit and collected data are send via GPRS or serial communication to server for storage, interpretation and transformation in form acceptable for end users. Integration of microcontroller inside sensor system allows implementation of automatic monitoring and support for management of the outer actuators and alarms.

Graphic LCD for Lightweight Electric Vehicles

In this paper, one solution of graphic LCD control board for lightweight electric vehicles is shown. The main idea was to build adoptable hardware solution that can be fast and easy applied in different electrical vehicles and easy for modifications. It was designed, built and tested graphic LCD for monitoring and seting up of main parameters and control signals for lightweight electric vehicle. Some of parameters that could be displayed on graphic LCD are charge status, actual speed, total mileage, daily mileage and indicators of direction. Also we discussed about other possibilities for some sensors that can be used to monitor vehicle speed and ways of visualizing the parameters of interest. The main principles that were used during the selection of hardware solutions implementation also are shown.