Jaromir Zak

Design of the charge push-through electronics for fully implantable artificial cochlea

The artificial cochlear implant is the only way how to get lost hearing back in some cases. Existing artificial cochlear devices use two separated parts for this purpose: a signal processing unit with transmitter and an implantable receiver with electrodes. This approach is applicable but not fully implantable. A new complex approach to design of a fully implantable artificial cochlea is described in this article. The proposed artificial cochlea consists of many subcircuits which have to be designed in close context to reach optimal performance and the lowest power consumption. Power consumption should be decreased to a value which allows using cochlear implant as a zero-powered system. A combination of micro-mechanized diaphragm filter bank, possible energy harvesting power source and especially ultra-low power processing electronics is presented in this article. A unique technique for nerve stimulatory output signal generation is discussed. This new technique named charge push-through electronics should use the major part of energy generated by energy harvesting subcircuit for output useful signal generation with minimal undesirable current. Mechanical parts of the subcircuits were simulated as complex electro-mechanical simulation models in ANSYS, CoventorWare, Matlab and SPICE environment. First, the real energy harvesting power source (human motion and temperature) behavior was measured. The model of this behavior was created in simulation environment and then the whole electronics simulation model for energy harvesting circuits was estimated. Next, signal processing circuits powered from energy harvesting power source were designed and simulated. The new signal processing circuits were simulated in relation to the results of complex electro mechanical diaphragm and SPICE energy harvesting power source simulation.

Zigbee-Based Wireless Distance Measuring Sensor System

A cost effective ZigBee-based wireless parking sensor system is presented in this article. Ultrasonic transmitter and receiver are used for distance measurement. An evaluation, control and wireless data transfer are realized by one chip – Panasonic hybrid chip PAN4450 (8-bit microcontroller + IEEE 802.15.4 radio). System consists of four independent distance sensors and one central display and control unit.

Development of wearable medical system for dehydration detection

This paper will be focused on the development of anew non-invasive and non-obtrusive medical wireless wearable system which is primarily used for dehydration detection but can be easily adapted to the measurement of other values. This system is used for real time telemonitoring of elderly people, diabetics and sportsmen during their normal life in this version. There are many devices used in the system shown in the fig. 1. The basis is formed by groups of sensors which contain on body sensors (temperature, humidity and trans-epidermal water-loss detector [1]), ambient sensors (urea potassium ions sensor and personal scales) and external devices (food scales).

Advanced mobile environment monitor with ability of pollution assessment

Monitoring environmental parameters as atmospheric pressure, temperature, humidity, dew-point are standards but pollution assessment is these days one of the most important areas of environmental measurements. In this work new modules for various values measurements are being developed. These modules are constructed for being connected to universal device called Environment Monitor which has been developed in our laboratories. The newest modules developed will be able to measure atmospheric precipitation acidity and conductivity to determine some parameters of the pollution. In connection to the later developed device for basic meteorological values measurements, the new complex device becomes a strong tool for ecology applications.

Electronic system for mass screening of toxic substances in environment

The work deals with n-channel system enabling many sample analysis at sort time from sensor array using electrochemical methods. The system is completely based on standard electronics technology as SMT and screen-printing. The 8x12 sensor arrays is formed from 3-electrodes system created on PCB with combination of galvanic deposition and screen-printing special paste on the electrodes which can be used for heavy metal analysis and also biomolecular complexes and organic toxic substances determination. The control unit switches each 3-electrode sensor to 8-channel precise potentiostat which was designed for electrochemical analysis with current sensitivity below 1 pA. The potentiostat can synchronize with control unit to depress time for analysis to minimum. Developed system is able to measure up to eight single inputs and may be simply converted to measure other values, AV or CV characteristics, transfer functions and nonlinear characteristics for example. Measured data will be sent to user-friendly application in computer and analyzed or saved consequently.