Data Acquisition
1. What is Data Acquisition (DAQ)?
Data acquisition (DAQ) refers to the process of automatically collecting analog signals (such as temperature, pressure, voltage and sound) or digital signals in the physical world through sensors or devices under test and converting them into digital data that can be processed by computers. Its core is to quantify continuous physical quantities into discrete digital signals, providing a basis for subsequent analysis, storage, and control.
2. What are the Core Components of DAQ System?
1) Sensors and Transducers
Convert non-electrical physical signals (such as temperature and pressure) into measurable electrical signals (voltage/current).
2) Signal Conditioning Module
Amplify, filter, isolate, and process the original signal to ensure acquisition accuracy.
3) Data Acquisition Equipment
Acquisition Card (DAQ Card): core hardware with built-in analog-to-digital converter (ADC), responsible for converting analog signals into digital quantities.
Interface Type: supports PCI, USB, Ethernet, etc. to realize data transmission with the computer.
4) Computer and Software
Driver Engine: coordinates communication between hardware and operating system (such as NI-DAQmx).
Application Software: Provides data analysis, visualization, and control functions (such as LabVIEW).
3. Technical Features and Selection Keys of Data Acquisition
Sampling Rate and Accuracy: The signal restoration capability is determined by the number of ADC bits (such as 16-bit) and the sampling speed (Samples/sec).
Synchronization and Control: Supports trigger signals, counters/timers to meet the timing requirements of complex scenarios.
Scalability: Compatible with multi-channel input, digital I/O (DIO), and bus synchronization (such as PXI).
4. What is Data Acquisition Used for?
Industrial Automation: Production line equipment status monitoring and control.
Scientific Research Experiments: High-precision physical/chemical signal acquisition and analysis.
Environmental Monitoring: Real-time acquisition of parameters such as temperature, humidity, and air pressure.
Consumer Electronics: Embedded data acquisition such as microphones and cameras.
5. Development Trend of Data Acquisition
Modern DAQ systems deeply integrate network communications and cloud platforms, support remote monitoring and real-time data analysis, and adapt AI algorithms to improve automated decision-making capabilities.
6. Data Acquisition FAQs
1) What are the core components of data acquisition?
Mainly includes sensors (pressure, temperature, humidity, etc.), signal conditioning devices (such as precision amplifiers and filters), analog-to-digital converters (ADCs), and isolation barriers (used to eliminate noise and ground interference).
2) How to ensure the accuracy of signal acquisition?
An isolated precision signal chain design (such as using transformers or optical couplers) is required to eliminate common-mode voltage changes, ground loops, and electromagnetic interference (EMI) while protecting sensitive components from voltage spikes.
3) What are the key parameters for sensor selection?
It is necessary to pay attention to the range (such as pressure sensors covering -14.5 to 10,000 PSI), interface type (USB/Ethernet), environmental adaptability (temperature/humidity range), and whether anti-interference design is required.