Virtual Instrumentation Flashcards

Flashcards covering key concepts from a lecture on virtual instrumentation, including its definition, history, components, LabVIEW, data acquisition, sensors, and applications.

What is Virtual Instrumentation?

A measurement and automation paradigm shift, using customizable software and modular hardware for user-defined systems.

How does Virtual Instrumentation differ from traditional instrumentation?

Virtual instruments are user-defined and software-based, offering flexibility and adaptability, while traditional instruments have fixed functionalities.

What are the core components of a virtual instrument system?

Sensors, a personal computer, data acquisition hardware, and dedicated software.

When did the conceptual foundations of virtual instrumentation begin to take shape?

In the late 1970s and early 1980s with the advancement of microprocessor technology.

What was a pivotal moment in the evolution of virtual instrumentation?

The introduction of graphical programming environments, most notably National Instruments' LabVIEW in 1986.

What are the advantages of virtual instrumentation?

Flexibility, customization, cost-effectiveness, scalability, modularity, rapid development, improved accuracy, enhanced data analysis, and remote accessibility.

What role does the computer play in a virtual instrumentation system?

The computer serves as the central hub, providing processing power, a user interface, and ports for interfacing with other hardware components.

What is the function of Data Acquisition (DAQ) devices?

To act as the interface between the computer and real-world analog signals, performing analog-to-digital conversion.

What is the purpose of sensors and transducers in a virtual instrumentation system?

To detect physical parameters and convert them into measurable electrical signals.

What are some common interfacing buses used in virtual instrumentation?

USB, PCI, PCI Express, Ethernet, and GPIB.

What is the role of driver software in virtual instrumentation?

To enable seamless communication between application software and DAQ hardware or external instruments.

What is Application-Specific Software?

Custom developed Software that defines the unique functionality of a virtual instrument.

What is the Front Panel in LabVIEW?

The interactive graphical user interface (GUI) of a LabVIEW Virtual Instrument (VI).

Define Controls in LabVIEW.

Interactive input elements placed on the Front Panel, such as knobs, pushbuttons and sliders.

What are indicators in LabVIEW?

Output display elements on the Front Panel, including graphs, charts, and numeric displays.

What is the Block Diagram in LabVIEW?

The graphical source code editor where the program's logic is constructed.

What are Terminals in LabVIEW?

Connection points that appear on the icons of Front Panel controls and indicators.

What are Nodes in LabVIEW?

The fundamental execution elements in the Block Diagram.

What are wires in LabVIEW?

Visual links between terminals representing the pathways through which data flows

What are pallets in LabVIEW?

Collections of tools and objects that LabVIEW provides for building the Front Panel and the Block Diagram

What programming paradigm does LabVIEW use?

Dataflow programming, where execution is determined by the availability of data at the inputs of nodes.

What is the function of the Tools Palette in LabVIEW?

Provides essential tools used to interact with and modify objects on both the Front Panel and Block Diagram.

Name a subpalette within the function pallette key for instrumentation

Data Acquisition (DAQmx VIs), Signal Processing, Analysis, File I/O, Instrument I/O (VISA Vis)

What is the difference between analog and digital signals?

Analog signals are continuous, while digital signals are discrete numerical values.

What is sampling rate?

The frequency at which a continuous analog signal is measured and converted into a discrete digital sample, expressed in samples per second (S/s) or Hertz (Hz).

What is resolution in data acquisition?

The number of bits used by the Analog-to-Digital Converter (ADC) to represent the amplitude of the analog signal.

What does the Nyquist Theorem state?

The sampling rate must be at least twice the highest frequency component present in the original analog signal to avoid aliasing.

What is Analog-to-Digital Conversion (ADC)?

The process of transforming a continuous analog signal into a discrete digital representation.

What is Digital-to-Analog Conversion (DAC)?

The reverse process of ADC, where a digital number is transformed back into a proportional analog voltage or current signal.

Name common types of temperature sensors.

Thermocouples, Resistance Temperature Detectors (RTDs), Thermistors and Integrated Circuit (IC) sensors.

Name common types of pressure sensors.

Strain Gauges, Piezoelectric Sensors, and Capacitive Sensors.

Name common types of flow sensors.

Turbine Meters, Magnetic Flow Meters, and Ultrasonic Flow Meters.

Distinguish between active and passive sensors.

Active sensors require an external power source, while passive sensors generate their own electrical signal.

What performance specifications should be considered when selecting Transducers?

Sensitivity, accuracy, range, resolution, response time, linearity, and hysteresis.

What are important considerations for Interfacing Sensors with DAQ Systems?

Matching sensor output to DAQ input range, appropriate wiring and connections and considering signal conditioning requirements.

What are common applications for Virtual Instrumentation?

Research and Development, Industrial Automation and Process Control, Testing and Measurement Systems, Biomedical Engineering and Healthcare, Education and Training, Aerospace and Automotive Industries.

What are common chart and graph types for measurement data?

Line Charts, Bar Charts, Scatter Plots, Histograms, XY Graphs, Waveform Charts and Graphs.

Name best practices for data presentation.

Choose the Right Chart Type, keep Visualizations Simple and Avoid Clutter and Ensure Data is Accessible

What factors influence Data Acquisition Accuracy?

Sensor Accuracy and Calibration, DAQ Hardware Specifications (Resolution, Sampling Rate, Noise), Environmental Conditions and Signal Conditioning Circuitry

What is the role of sensor calibration in data acquisition?

To maintain accuracy over time by comparing the sensor's output against a known standard and adjusting the system to minimize deviations.

What are future trends and advancements in virtual instrumentation?

Integration with cloud computing and IoT, advancements in sensor technology and DAQ hardware and incorporation of data analytics and machine learning capabilities.