|Monday, 18 December 2006|
Data recorders are used in many industrial and commercial applications. The need for continuity of data collection and display is most pressing in emergency situations. Generally, it is very advantageous to know the condition or states of a vehicle of an aircraft when a traffic accident has occurred involving the vehicle, in order to look into the cause of the accident. As an example of apparatus representative for storing data at a traffic accident occurrence time, a flight recorder mounted on an aircraft is well known. Aircraft flight and performance parameters are monitored and recorded for recording of primary flight parameters for retrieval and analysis in the event of an aircraft mishap or crash as well as recording and analysis of various aircraft flight and performance parameters to assist in aircraft maintenance and to monitor both aircraft and crew performance. Commercial aircraft employ a flight data recorder (FDR) and a voice data recorder (VDR) to aid in the accident reconstruction and diagnostic process. The FDR records various flight parameters such as engine status, fuel status, airspeed, altitude, attitude and control settings. The VDR typically records the voice communications of the crew members, although it may also pick up other extraneous noise in the cockpit such as an explosion. Modem aircraft currently operated by commercial airlines typically employ an onboard data acquisition system for collecting digital flight data. In such systems, a number of sensors distributed throughout the aircraft provide data signals representative of the performance of the aircraft and its engines. This flight data is stored in an attendant, physically robust flight data recorder (black box), so that in the unlikely event of an in-flight mishap, the flight data recorder can be removed and the stored flight performance data can be analyzed to determine the cause of the mishap. The flight performance data may be transmitted to an aircraft communication and reporting system (ACARS) management unit for real-time transmission of, for example, snapshot position parameters, to the ground. The flight performance data is also provided to a pilot interface, such as a multifunction condition and display unit (MCDU). The MCDU can display real-time parameters for maintenance and piloting. Flight data recorders usually incorporate printed electrical cards on which the electronic components are held in place by electrical solder pads to form integrated circuits.
In certain industries such as electrical utilities, oil well logging and other industries, large amounts of data obtained from monitoring and testing are processed and analyzed to yield useful information. For example, in the electrical utility industry, data recorders monitor electrical power lines for signal fluctuations indicative of problems in the transmission line. Typical power line fault recorders record analog data from the voltages and currents generation stations. In power line monitoring data recorders, components known as continuous monitoring equipment (CME) detect the occurrence of a fault condition and initiate the recording of data for subsequent analysis. In the oil and gas industry, the importance of obtaining various borehole measurements during the course of a drilling operation have long been recognized. Typically, these measurements include such data as the weight imposed on the drill bit, the torque applied to the drill string, the inclination and azimuthal direction of the borehole interval that is then being drilled, borehole pressures and temperatures, drilling mud conditions as well as formation parameters including resistivity and natural gamma emission of the earth formations being penetrated. Measurement-while-drilling or MWD tools are coupled in the drill string and operated during the drilling operation. Several MWD tools in commercial operation typically include a thick-walled tubular body carrying various sensors and their associated measurement-encoding circuitry which is preferably positioned in the drill string just above the drill bit for measuring the conditions near the bottom of the borehole. Use of data recorders is especially commonplace in shipment and storage situations requiring strict documentation for quality assurance, since molecular structures can be changed by improper temperature maintenance, and such change can ruin perishable items. Like temperature, other factors such as humidity, vibration, and levels of oxygen, nitrogen and other gases can also have a profound effect on cell biology and molecular structure during storage and transportation.
Facility control is often performed by a number of different control systems having a variety of controllers. Some of the control systems may have man-machine interfaces such as touch screens, while others may only collect and display one variable such as temperature. The monitoring systems collect data tabulated for the process control system. The data collection of the monitoring system handles univariate and multivariate data, the analysis and display of the data, and has the ability to select the process variables to collect. Semiconductor processing facilities require constant monitoring. Processing conditions change over time with the slightest changes in critical process parameters creating undesirable results. Small changes can easily occur in the composition or pressure of an etch gas, process chamber, or wafer temperature. Computers are generally used to control, monitor, and initialize manufacturing processes. To detect leakage beyond a metering point is of critical importance in some industries, utilities generally deploy data recorders to monitor intervals over a time period of interest. The data recorded is left in place, logging water consumption over a series of short interval. Post analysis of the data recorder looks for the minimum consumption level with the theory that at least one interval will register zero consumption if there are no leaks. A computer is ideal for these operations given the complexities in a semiconductor manufacturing plant from the reentrant wafer flows, critical processing steps, and maintainability of the processes. Various conditions in a process are monitored by different sensors provided in each of the process chambers, and data of the monitored conditions is transferred and accumulated in a control computer. If the process data is displayed and detected automatically, the optimum process conditions of a mass-production line can be set and controlled through statistical process control (SPC) charts.