Tadeusz Sondej

Architecture of car measurement system for driver monitoring

This paper addresses the todays social needs to ensure security in road traffic, a task which becomes difficult due to the growing number of drivers and, therefore, increasing traffic intensity. The rising need for mobility constitutes a huge challenge for the institutions responsible for improving the road traffic safety. The paper describes selected hardware components which can be used to build an integrated warning system. Its measuring modules supply data on the road traffic environment parameters, the vehicle dynamics, and psychophysiological behavior of the drivers. An important aspect of interoperation of such hardware components is reliable communication and data synchronization. The presented solutions are based on the CAN, WiFi, ISM 2.4 GHz, and GSM/GPRS interfaces. To minimize the risk of data loss, the data is stored redundantly in the local memory structures, as well as in a remote archiving system to which the data is transmitted through wireless communication protocols.

First approach for design of an autonomous measurement system to aid determination of the psychological profile of soldiers

The article presents the first attempt for design of an autonomous measurement system to aid assessment and to determine the psychological profile of soldiers. A method for ascertaining the psychological profile is presented including the physiological signals being generated by the monitored subject as an important element thereof. The measurement system used in the preliminary experiments and the design of a new, extended-functionality system, are presented. The new version of the measurement system facilitates determination of physiological parameters, environmental conditions and physical activity. In addition, it allows introduction of data on the psychological profile of the soldier to determine the degree of a soldiers adaptation to task-related situation at given point in time. The main element of the measurement system has been designed using an application-specific integrated circuit.

Wireless driver and vehicle surveillance system based on IEEE 802.11 networks

The paper presents a complex system for driver and vehicle surveillance. System uses many different sensors such as acceleration sensors, ECG and blood pressure measuring devices, eye movement recorders, video cameras, GPS and wireless IEEE 802.11 networks for transmission of recorded data in real time. The paper presents also two experiments with their results and a method to calculate a metric characterizing the drivers technique that uses signals recorded during the experiment.

Autocorrelation algorithm for determining a pulse wave delay

This article concerns an autocorrelation algorithm for determining a pulse wave delay. The pulse wave delay is defined as difference between the characteristic points i.e. the difference between the R wave in the electrocardiogram signal (ECG) and distinctive point in the photoplethysmogram (PPG) waveform. Obtaining values of the characteristic points (time stamps) are realized by correlation function. The known values of the time stamps can be used to estimate change of blood pressure. In the proposed algorithm using the autocorrelation function is calculated signal pattern. Then, this pattern is used for further correlation calculations. In the algorithm all the time is analysed the quality of the measured signal. In the next part of article was described method of measurement and the results calculated the time of the characteristic points to determine the pulse wave delay.

A method for real-time data acquisition using Matlab software

The article presents the method for real-time data acquisition from external devices using Matlab software. The protocol and the transfer frame, enabling faultless communication of the master system with external measuring sensors have been described. The article includes a description of a measuring station, implementing the proposed protocol, as well as a detailed description of the algorithm of test programs. Three performance tests were performed as part of the experimental studies. They make it possible to assess: (1) the average transmission time, (2) the effective throughput of a full cycle of data exchange, (3), the required working time of Matlab to handle the transmission, and (4) the stability of the program timer used for periodic data transmission calls. The tests were carried out for three commonly used communication interfaces (UART, Bluetooth, WiFi) and for different sizes of packets transmitted.

Implementation of an algorithm for heart rate measurement in a specialized multi-core processor

The article presents the method for implementation and results of examination of the Pan-Tompkins algorithm using a specialized 4-core Azurite processor, based on MIPS-II instruction set. The algorithm is used to determine heart rate on the basis of ECG signals. Azurite is a Multiprocessor System-on-Chip featuring an analog and a digital part. The digital part has been implemented in a Xilinx Virtex-6 FPGA system. An experimental study was carried out using one and three cores of Azurite processor as well as using the widely available microprocessor of the STM32F4 series (based on Cortex-M4F core). Same results were obtained for both types of cores. Division of the Pan-Tompkins algorithms into stages processed in 3 processor cores allowed for a 2.5 speedup of computations. Processing of a 27-second fragment of the ECG signal (sampling frequency of 250 Hz) using three cores of the Azurite processor (processor clock frequency of 100 MHz) took as little as 6.9 ms.

Fuzzy calibration for pulsed time-of-flight laser rangefinder

A fuzzy approach to real-time calibration of mobile laser rangefinder is presented as an alternative to the methods based on adaptive algorithms. The main error source in such a measurement system is drift error due to the changes of ambient temperature. It may be compensated using repeatedly performed calibration based on the time-of-flight measurement of laser pulse propagating through the constant section of optical fiber. To minimize calibration rate we designed fuzzy calibrator that traces actual changes of drift error and calculates the optimum rate of calibration. This method has been tested using mobile laser rangefinder with 3 cm single-shot accuracy

REFLECTANCE METHOD FOR A WEARABLE PHOTOPLETHYSMOGRAPHIC SENSOR – EXPERIMENTAL EVALUATION

This is an open-access ar cle distributed under the terms of the Crea ve Commons A ribu on Non-commercial License (h p://crea vecommons.org/licenses/by-nc/3.0), which permits use, distribu on, and reproduc on in any medium, provided the original work is properly cited, the use is non-commercial and is otherwise in compliance with the license. The article presents the design and testing results of a photoplethysmographic signal sensor intended for use in everyday activities.

Picosecond-precision multichannel autonomous time and frequency counter

This paper presents the design, implementation, and test results of a multichannel time interval and frequency counter developed as a desktop instrument. The counter contains four main functional modules for (1) performing precise measurements, (2) controlling and fast data processing, (3) low-noise power suppling, and (4) supplying a stable reference clock (optional rubidium standard). A fundamental for the counter, the time interval measurement is based on time stamping combined with a period counting and in-period two-stage time interpolation that allows us to achieve wide measurement range (above 1 h), high precision (even better than 4.5 ps), and high measurement speed (up to 91.2 × 106 timestamps/s). The frequency is measured up to 3.0 GHz with the use of the reciprocal method. Wide functionality of the counter includes also the evaluation of frequency stability of clocks and oscillators (Allan deviation) and phase variation (time interval error, maximum time interval error, time deviation). The 8-channel measurement module is based on a field programmable gate array device, while the control unit involves a microcontroller with a high performance ARM-Cortex core. An efficient and user-friendly control of the counter is provided either locally, through the built-in keypad or/and color touch panel, or remotely, with the aid of USB, Ethernet, RS232C, or RS485 interfaces.

Design Of A Multisensor System For A Highly Integrated Driver Fatigue Monitoring Technology

This paper describes the architecture and use of a multisensor system for estimating a driver’s fatigue level. These sensors are an element of the integrated system for monitoring a driver’s behavior, also including the measurement of environmental conditions and driving technique. Sensors described in the paper are designed to work under simulated and real conditions (when driving a vehicle). To estimate the level of driver fatigue, we used a subsystem for measuring eye closing frequency and oculomotor activity (Eye Activity Monitoring Subsystem), a personal medical set and a non-contact electrocardiography signal measurement module. In addition, for comparison purposes, we used commercial solutions called faceLAB 5 (system for tracking and testing eye activity) and FlexComp (system for measuring physiological activity). The paper presents a description of the sensors, their communication with the LoggerBox master device, and their location in the car. It also presents a typical test procedure and sample signals recorded during driving.