Data acquisition systems, shortened to DAS, are systems designed to convert analog waveforms into digital values, so that they can be used for processing. Industries that make use of this technology include aerospace, medicine, wastewater services, and industrial manufacturing. The process involves the sampling and converting of electrical or physical phenomenon or property into data and inputting the data into a computer. Examples of phenomena and properties include voltage, current, sound, fluid flow, gas pressure, force, temperature, and light intensity.
Once the data has been converted into a singular form, it can be accessed and controlled by data acquisition software programs that use a variety of programming languages, such a Pascal, Lisp, BASIC, C++, LabVIEW, and Java. In addition to allowing manufacturers to read data, data acquisition systems allow them to test a wide variety of technical products and make informed process adjustments.
The use of general purpose programming by data acquisition processes (DAQ), as opposed to application or industry-specific programming, is the reason that data acquisition systems are able to be used with so many applications. Applications include flight data acquisition, structural dynamics test systems, local electronic data capture systems, and central web-based systems for clinical trial data, collection of wastewater toxicity and treatment response data and data collection via PC-based systems and chart recorders. In general, data acquisition systems are most often used to conduct testing for field studies, research, and product troubleshooting. Read More…
There are a variety of ways by which researchers may collect data. Two of the most common methods of data acquisition are personal computer (PC) data acquisition and universal serial bus (USB) data acquisition. Most data acquisition systems employ some sort of PC method; the term PC data acquisition covers all data acquisition systems and devices that require a connection to a host computer to properly download collected information and generally operate.
In fact, the device used by the other common method of data acquisition, the USB device, technically employs PC data acquisition, because the USB device works by plugging directly into a host computer. However, USB data acquisition is still a method of its own. It uses the USB device, which is a serial bus that today is a staple for connecting and maintaining conversation between data acquisition devices and their host controllers, which are usually computers.
USB data acquisition systems feature many attractive characteristics, such as higher bandwidth (up to twelve megabytes per second) and the ability to provide power to peripheral devices. In addition, because USB devices are used to supply power, they only need one cable in order to be linked to a computer, usually via a USB port.
Three important components of data acquisition systems include sensors, signal conditioning circuitry, and analog-to-digital converters. Sensors are essential to the function of these systems, as they are the tools that detect and convert physical data into electrical signals. Signal conditioning circuitry, also called signal conditioners, provide similar conversion services, but they work one step down the line by converting the signals provided by the sensors into a more digestible form that are easier to convert into digital values.
Analog-to-digital converters are also important to the function of data acquisition systems because they provide the final step of conversion; they fully convert the sensor signals after they have been partially converted by the signal conditioning circuitry.
In addition to these, data acquisition systems may be equipped with any number of supplementary tools or devices, such data acquisition cards, which may be defined as electronic hardware that works when it is physically plugged into a computer. (A small number of data acquisition cards are able to run independently.) This type of hardware serves as an interface between the sensor signal and a computer.
Data loggers, also known as data recorders, are any device that is able to store data. Other optional data acquisition system components include data loggers and temperature recorders. Data logging equipment includes serial communication systems and plug-in boards. Note that while data loggers may be used as a part of a whole system, they are more often used by themselves, with or without a computer connection.
Temperature recorders are in fact a type of data logger, used specifically to measure physical temperature. They can be powered by digital, analog, or mechanical means and after the data has been collected and converted, it is downloaded onto a computer. Here, it can be used to help meteorologists monitor meteorological conditions and to aid different types of laboratory research.