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Digital to analog converter_Mechatronics
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Data Acquisition System • Data acquisition is the process of digitizing data from the world around us so it can be displayed, analyzed, and stored in a computer.
Data acquisition is the process of sampling signals that measure real world physical conditions and converting the resulting samples into digital numeric values that can be manipulated by a computer. • Data acquisition systems, abbreviated by the initialisms DAS,DAQ,or DAU, typically convert analog waveforms into digital values for processing.
The components of data acquisition systems include: • Sensors, to convert physical parameters to electrical signals. • Signal conditioning circuitry, to convert sensor signals into a form that can be converted to digital values. • Analog-to-digital converters, to convert conditioned sensor signals to digital values.
Data acquisition is the process of measuring physical world conditions and phenomena such as electricity, sound, temperature and pressure. • This is done through the use of various sensors which sample the environment’s analog signals and transform them to digital signals using an analog-to-digital converter. • The resulting digital numeric values can then be directly manipulated by a computer, allowing for the analysis, storage and presentation of these data.
The term "data acquisition" refers to software and hardware that we use to measure the physical characteristics of real world processes. • With the term "control", we refer to the process of making changes to specific attributes in the real world. • I use the words "real world" to emphasize the fact that data acquisition and control deal with processes outside of a computer. • We use sensors to convert real world signals to binary code so that computers can store and process them. And we use actuators (motors, relays, etc.) to control specific attributes in the real world.Data acquisition and control technologies are very common in industrial settings, such as factories and warehouses. Over the last 20 years, data acquisition and control is a common part of our everyday experience. Modern cars are filled with computers and sensors, collecting data and making decisions that control every aspect of engine and subsystem operations. Homes are also becoming automated using similar technologies.
Data acquisition applications are usually controlled by software programs developed using various general purpose programming languages such as Assembly, BASIC, C, C++, C#, Fortran, Java, LabVIEW, Lisp, Pascal, etc. Stand-alone data acquisition systems are often called data loggers.
Why is this useful? • Because of what computers can do with this binary number, which, remember, represents the original real world signal. • Computers can use this number to control actuators. Actuators are devices that produce some kind of work. Examples of actuators are motors, industrial ovens, relays, and solenoids.Computers can also rapidly analyze large numbers of real world signals. The result of the analysis allows us to understand some aspect of our world. A revolutionary new technology that depends on large data set analysis is artificial intelligence and machine learning. The result of these technologies is computers that can make decisions. From washing machines to self-driving cars and Mars rover explorers, smart machines depend on the data acquisition, analysis, and control processes.
What is Signal Conditioning? • Most analog signals require some form of preparation before they can be digitized. Signal conditioning is the manipulation of a signal in a way that prepares it for the next stage of processing. • Many applications involve environmental or structural measurement, such as temperature and vibration, from sensors. These sensors, in turn, require signal conditioning before a data acquisition device can effectively and accurately measure the signal.
For example, thermocouple signals have very small voltage levels that must be amplified before they can be digitized. • Other sensors, such as resistance temperature detectors (RTDs), thermistors, strain gages, and accelerometers, require excitation to operate. All of these preparation technologies are forms of signal conditioning. Sometimes, Sensor itself have SC, but many cases we required a separate SC system
Microcontroller System • A microcontroller is a computer present in a single integrated circuit which is dedicated to perform one task and execute one specific application. • It contains memory, programmable input/output peripherals as well a processor. Microcontrollers are mostly designed for embedded applications and are heavily used in automatically controlled electronic devices such as cellphones, cameras, microwave ovens, washing machines, etc. A microcontroller is a compact integrated circuit designed to govern a specific operation in an embedded system. A typical microcontroller includes a processor, memory and input/output (I/O) peripherals on a single chip.
A microcontroller is a small and low-cost microcomputer, which is designed to perform the specific tasks of embedded systems like displaying microwave’s information, receiving remote signals, etc. • The general microcontroller consists of the processor, the memory (RAM, ROM, EPROM), Serial ports, peripherals (timers, counters), etc.
https://techexplorations.com/guides/labjack/what-is-daq/ • https://dewesoft.com/daq/types-of-data-acquisition-systems • https://www.youtube.com/watch?v=-0LzMfhoSts • https://www.youtube.com/watch?v=hscfyjZSCVM • https://www.youtube.com/watch?v=215zRBV1iFY • https://www.youtube.com/watch?v=I_9Pwyxhe40 (NPTEL)
Why you should have data acquisition system • Improves the efficiency and reliability of processes or machinery. Steel mills, utilities, or a research lab have some kind of data acquisition device that silently monitors some parameter. These collected data can be used to improve efficiency, ensure reliability or ensure that machinery operates safely. 2. Problems are analyzed and solved faster. With the use of real-time data acquisition systems, measurements are generated and displayed without delay. Thanks to this system, a technician can intervene faster in any problem and make the machine reach optimum performance in less time.
3. Data redundancy is reduced. With the application of a system of this type, companies forget to have duplicate data and adopt a technology that facilitates the analysis of the information obtained, as it allows them to work without any noise that hinders the analysis. 4. Decrease update errors. This type of system automates data entry processes that were previously done by hand. Automation reduces errors by eliminating human error and misplacement.
5. Increased data integration and reliance on other programs. The fewer programs that intervene in a more agile process, the more agile it will be. Thanks to a DAQ system, it ensures that the information is complete and correct without having to rely on other types of applications. 6. Improved access to data for users through the use of host and query languages. With these systems it is easier to access the database and retrieve information for processing and analysis.
7. Improves data security. By automating the process of capturing data from reality, the human factor is no longer involved and the security risks associated with this procedure are reduced. 8. Data entry, storage and retrieval costs are reduced. These three processes are cheaper because data is entered faster, takes up less space, and can be retrieved in less time.
9. Quality control. A system of this type can confirm that a system is meeting the design specifications and that a product meets the user’s needs. In addition, you can test whether a product has the quality required for marketing and detect those that are defective. 10. Supervision of processes without human interaction. With such a system, the company’s various procedures are tracked and monitored to identify and resolve faults faster.
With multiplexing, a measuring system is able to sequentially channel multiple signals to a single digital converter, thereby providing a low-cost means of increasing the number of channels of the system. • A multiplexer consists of a set of switches and provides a significant cost reduction by making use of just one A/D converter for multiple inputs. • A multiplexer is a system of multiple inputs and just one output to receive signals coming from multiple acquisition networks.
