Virtual instrumentation uses customizable software and modular hardware to create user-defined measurement systems called virtual instruments. It emerged in the late 1970s with advances in microprocessor technology that enabled instrument functions to be changed via software instead of hardware. Virtual instrumentation progressed through three phases: early analog devices, digitization of signals in the 1950s, and computer-based instruments with interfaces in the 1960s, making instruments more affordable and flexible. Key advantages of virtual instruments over traditional hardware-focused instruments are lower cost, user-defined functionality, and faster technology updates.

1. VIRTUAL INSTRUMENTATION

2. INTRODUCTION
 Virtual instrumentation is the use of customizable software and modular
measurement hardware to create user-defined measurement systems, called
virtual instruments.
 It is an interdisciplinary field as it merges sensing, hardware and software
technologies.
 It is used to create flexible and sophisticated instruments for control and
monitoring applications.

3. HISTORY
 The concept of Virtual instrumentation was born in late 1970’s.
 microprocessor technology enabled amachine’s function to be more
easily changed by changing its software.
 Flexibility is possible as the capabilities of a virtual instrument depend very
little on dedicated hardware.
 There are broadly 3 phases of Virtual Instrumentation
• First phase
• Second phase
• Third phase

4. FIRST PHASE
 It is represented by early “pure” analog measurement devices, such as
oscilloscopes etc.
 They were completely closed dedicated systems, which included power
suppliers, sensors, translators and CRT displays.
 They required manual settings, presenting results on various counters,
gauges, CRT displays, or on the paper.

5. SECOND PHASE
 It is started in 1950s, as a result of demands from the industrial control field.
 Instruments started to digitalize measured signals, allowing digital processing of
data.
 This led to creation of proportional-integral-derivative (PID) control systems,
which allowed greater flexibility of test procedures and automation of some
phases of measuring process.

6. THIRD PHASE
 It began around 1960’s where the Analog measuring instruments become
computer based.
 They begun to include interfaces that enabled communication between the
instrument and the computer.
 This relationship started with the general-purpose interface bus (GPIB)
originated in 1960’s by Hewlett-Packard (HP), then called HPIB, for
purpose of instrument control by HP computers.
 As a result, virtual instrumentation made possible decrease in price of an
instrument.
 As the virtual instrument depends very little on dedicated hardware, a
customer could now use his own computer.

7. TRADITIONAL INSTRUMENTS VS
VIRUAL INSTRUMENTS
TRADITIONAL INSTRUMENTS VIRTUAL INSTRUMENTS
• Vendor-defined • User-defined
• Hardware is the key • Software is the key
• Expensive • Low-cost, reusable
• Closed, fixed functionality • Open, flexible functionality
• Slow turn on technology (5–10 year life
cycle)
• Fast turn on technology (1–2 year life
cycle)
• Minimal economics of scale • Maximum economics of scale
• High development and maintenance
costs
• Minimizes development and
maintenance costs.

8. TRADITIONAL
INSTRUMENTS
VIRTUAL INSTRUMENT

9. APPLICATIONS
 DESIGN
 Signal and image processing
 Simulation and prototyping
 Control
 Automatic controls and dynamic systems
 Mechatronics and Robotics
 Measurements
 Circuits and electronics
 Measurements and instrumentation

10. ADVANTAGES
 Lower cost of instrumentation
 Easy-to-use graphical user interface
 Portability between various computer platforms
 Increases the utility of computer
 Flexibility

11. DISADVANTAGES
 Security- Sensitive information may be accessible to public users.
 Power Consumption- Virtual Instrumentation demands that many devices
run simultaneously and can consume a lot of power. Each computer will
consume a large amount of power in addition to any external hardware.
 High Implementation cost.

12. THANK YOU