The major parts in the Blue eye system are Data Acquisition Unit and Central System Unit. The tasks of the mobile Data Acquisition Unit are to maintain Bluetooth connections, to get information from the sensor and sending it over the wireless connection, to deliver the alarm messages sent from the Central System Unit to the operator and handle personalized ID cards. Central System Unit maintains the other side of the Bluetooth connection, buffers incoming sensor data, performs on- line data analysis, records the conclusions for further exploration and provides visualization interface.
THE HARDWARE: Data Acquisition Unit: Data Acquisition Unit is a mobile part of the Blue eyes system. Its main task is to fetch the physiological data from the sensor and to send it to the central system to be processed. To accomplish the task the device must manage wireless Bluetooth connections (connection establishment, authentication and termination). Personal ID cards and PIN codes provide operators authorization. communication with the operator is carried on using a simple 5-key keyboard, a small LCD display and a beeper. When an exceptional situation is detected the device uses them to notify the operator.
Voice data is transferred using a small headset, interfaced to the DAU with standard mint-Jack plugs. The Data Acquisition Unit comprises several hardware modules * Atmel 89C52 microcontroller system core * Bluetooth module (based on ROK101008) * HD44780 small LCD display * 12C EEPROM (on a removable ID card) * MC145483 13bit PCM codec * Jazz Multisensor interface * beeper and LED indicators ,6 AA batteries and voltage level monitor CENTRAL SYSTEM UNIT: Central System Unit hardware is the second peer of the wireless connection.
The box contains a Bluetooth module (based on ROK101008) and a PCM codec for voice data transmission. The module is interfaced toa PC using a parallel, serial and USB cable. The audio data is accessible through standard mint-Jack sockets To program operators personal ID cards we developed a simple programming device. The programmer is interfaced to a PC using serial and PS/2 (power source) ports. Inside, there is Atmel 89C2051 microcontroller, which handles UART transmission and 12C EEPROM (ID card) programming. THE SOFTWARE: Blue Eyes softwares main task is to look after working operators physiological condition.
To assure instant reaction on the operators condition change the software performs real time buffering of the incoming data, real-time physiological data nalysis and alarm triggering. The Blue Eyes software comprises several functional System core facilitates the transfers flow between other system modules (e. g. transfers raw data from the ConnectionManager to data analyzers, processed data from the data analyzers to GUI controls, other data analyzers, data logger etc. ). The System Core fundamental are single-producer-multi-consumer thread safe queues.
Any number of consumers can register to receive the data supplied by a producer. Every single consumer can register at any number of producers, receiving therefore different types of data. Naturally, every consumer may be a producer for other consumers. This approach enables high system scalability new data processing modules (i. e. filters, data analyzers and loggers) can be easily added by simply registering as a costumer. Connection Manager is responsible for managing the wireless communication between the mobile Data Acquisition Units and the central system.
The Connection Manager handles: * communication with the CSU hardware * searching for new devices in the covered range * establishing Bluetooth connections * connection authentication * incoming data buffering sending alers Data Analysis module performs the analysis of the raw sensor data in order to obtain information about the operators physiological condition. The separately running Data Analysis module supervises each of the working operators. The module consists of a number of smaller analyzers extracting different types of information.
Each of the analyzers registers at the appropriate Operator Manager or another analyzer as a data consumer and, acting as a producer, provides the results of the analysis. The most important analyzers are: * saccade detector monitors eye movements in rder to determine the level of operators visual attention * pulse rate analyzer uses blood oxygenation signal to compute operators pulse rate * custom analyzers recognize other behaviors than those which are built-in the system. The new modules are created using C4. decision tree induction algorithm Visualization module provides a user interface for the supervisors. It enables them to watch each of the working operators physiological condition along with a preview of selected video source and related sound stream. All the incoming alarm messages are instantly signaled to the supervisor. The Visualization module can be set in an off-line mode, where all the data is fetched from the database. Watching all the recorded physiological parameters, alarms, video and audio data the supervisor is able to reconstruct the course of the selected operators duty