RESUMEN
Nonintrusive monitoring of a driver's physiological signals was introduced and evaluated in a car as a test of extending the concept of ubiquitous healthcare to vehicles. Electrocardiogram, photoplethysmogram, galvanic skin response, and respiration were measured in the ubiquitous healthcare car (U-car) using nonintrusively installed sensors on the steering wheel, driver's seat, and seat belt. Measured signals were transmitted to the embedded computer via Bluetooth(R) communication and processed. We collected and analyzed physiological signals during driving in order to estimate a driver's stress state while using this system. In order to compare the effect of stress on physical and mental conditions, two categories of stresses were defined. Experimental results show that a driver's physiological signals were measured with acceptable quality for analysis without interrupting driving, and they were changed meaningfully due to elicited stress. This nonintrusive monitoring can be used to evaluate a driver's state of health and stress.
Asunto(s)
Conducción de Automóvil , Automóviles , Electrocardiografía Ambulatoria/instrumentación , Monitoreo Fisiológico , Estrés Psicológico , Adaptación Psicológica , Adulto , Estado de Salud , Humanos , Masculino , PsicometríaRESUMEN
A helmet-based system that was able to monitor the drowsiness of a soldier was developed. The helmet system monitored the electrocardiogram, electrooculogram and electroencephalogram (alpha waves) without constraints. Six dry electrodes were mounted at five locations on the helmet: both temporal sides, forehead region and upper and lower jaw strips. The electrodes were connected to an amplifier that transferred signals to a laptop computer via Bluetooth wireless communication. The system was validated by comparing the signal quality with conventional recording methods. Data were acquired from three healthy male volunteers for 12 min twice a day whilst they were sitting in a chair wearing the sensor-installed helmet. Experimental results showed that physiological signals for the helmet user were measured with acceptable quality without any intrusions on physical activities. The helmet system discriminated between the alert and drowsiness states by detecting blinking and heart rate variability (HRV) parameters extracted from ECG. Blinking duration and eye reopening time were increased during the sleepiness state compared to the alert state. Also, positive peak values of the sleepiness state were much higher, and the negative peaks were much lower than that of the alert state. The LF/HF ratio also decreased during drowsiness. This study shows the feasibility for using this helmet system: the subjects' health status and mental states could be monitored without constraints whilst they were working.
Asunto(s)
Dispositivos de Protección de la Cabeza , Monitoreo Ambulatorio/instrumentación , Procesamiento de Señales Asistido por Computador/instrumentación , Vigilia/fisiología , Parpadeo/fisiología , Electrocardiografía/instrumentación , Electrocardiografía/métodos , Electrodos , Electroencefalografía/instrumentación , Electrooculografía/instrumentación , Movimientos Oculares/fisiología , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Fases del Sueño/fisiología , Telemetría/instrumentaciónRESUMEN
In the military, there are many dangerous, difficult working conditions. Sometimes soldiers have to cope with the enemy and cannot sleep all the day because of overnight training or operation. So the health state of serviceperson has been the main concern of the commander. Despite the importance, to monitor the health condition of the serviceperson without influence of daily schedule or combat situation is very difficult, because there are so many artifact sources in the field. And the devices which monitor the subjects need the additional work and subjects need to be very careful doing something with devices. We intend to develop the system that can monitor the soldier's biomedical signal unconstrainedly. In this paper we introduce the prototype of our helmet based system. This system measured the ECG, EOG and Eye Blink successfully.
Asunto(s)
Parpadeo/fisiología , Electrocardiografía Ambulatoria/instrumentación , Electrooculografía/instrumentación , Dispositivos de Protección de la Cabeza , Personal Militar , Adulto , Electrocardiografía Ambulatoria/métodos , Electrooculografía/métodos , Humanos , Masculino , Monitoreo Ambulatorio/instrumentación , Monitoreo Ambulatorio/métodosRESUMEN
Measurement of driver's state is important in both daily healthcare and prevention of car accidents. Existing measurement methods, however, are too complex and uncomfortable to measure for everyday. A nonintrusive biosignal monitoring system is demanded for increasing the accessibility. In this paper, we proposed a nonintrusive measurement system integrated in a vehicle for recording electrocardiographic (ECG) signals and tested the performance of the system. The system consists of dry electrodes attached to the steering wheel and a wireless communication module using a Bluetooth device. ECG signals measured by our system were compared with those by a conventional system employing wet electrodes during real city road driving. Various parameters used for HRV analysis in time and frequency domain showed no significant differences between the two simultaneously measured ECG signals. The result implies the possibility that developed system could have a potential to monitor health information in a vehicle instead of commercial equipments.
Asunto(s)
Conducción de Automóvil , Electrocardiografía/instrumentación , Monitoreo Fisiológico/instrumentación , Adulto , Algoritmos , Redes de Comunicación de Computadores , Interpretación Estadística de Datos , Electrocardiografía/métodos , Electrodos , Diseño de Equipo , Frecuencia Cardíaca , Humanos , Masculino , Monitoreo Fisiológico/métodos , Vehículos a Motor , Procesamiento de Señales Asistido por Computador , Factores de TiempoRESUMEN
A personal computer (PC)-based audiometer was developed for interactive remote audiometry. This paper describes a tele-audiometric system and evaluates the performance of the device when compared with conventional face-to-face audiometry. The tele-audiometric system is fully PC-based. A sound card featuring a high-quality digital-to-analog converter is used as a pure-tone generator. The audiometric programs were developed based on Microsoft Windows in order to maximize usability. Audiologists and their subjects can use the tele-audiometry system as one would utilize any PC application. A calibration procedure has been applied for the standardization of sound levels in the remote system. The performance of this system was evaluated by comparing PC-based audiometry with the conventional clinical audiometry system for 37 subjects. Also, performance of the PC-based system was evaluated during use at a remote site. The PC-based audiometry system estimated the audiometric threshold with an error of less than 2.3 dBSPL. Only 10.7% of the results exhibited an error greater than 5 dBSPL during use at a remote site. The PC-based tele-audiomerty showed acceptable results for use at a remote site. This PC-based system can be used effectively and easily in many locations that have Internet access but no local audiologists.