NASA - National Aeronautics and Space Administration
Follow this link to skip to the main content
+ Visit NASA.gov
+ Contact NASA
ABOUT NASA LATEST NEWS MULTIMEDIA MISSIONS MY NASA WORK FOR NASA

+ Home
Aviation Systems Division
ABOUT US
ATM RESEARCH
FACILITIES & CAPABILITIES
LATEST NEWS
PUBLICATIONS
RESOURCES
MULTIMEDIA
Go


SimLabs Logo
Aviation Systems Division. Image of a simulation in FutureFlight Central.

+ Home > Facilities & Capabilities > VMS > Flight Controls > Computers


ANALOG AND DIGITAL COMPUTERS
Contents Follow this link to skip to the main text.
RELATED LINKS
Vertical Motion Simulator
+ Overview
+ ICABs
+ Motion Base
+ OTW Graphics
+ Flight Instruments
+ Flight Controls
+ VMS Lab
+ Virtual Lab
+ RITE
+ Research
+ Projects
+ Multimedia Gallery

SimLabs
+ FFC
+ CVSRF
+ VAST-RT

Picture of an analog clock.
Analog Clock



Picture of a digital clock
Digital Clock
Most information can be represented by analog or digital methods. To understand this, consider a clock.

A dial clock is an analog representation of time. The hands move continuously; that is, they sweep through all points on the dial.

A digital clock does not represent time continuously, but rather discretely, in distinct steps. A digital clock might display whole seconds but not the time in between the seconds. For increased accuracy, a digital clock could also display parts of a second: tenths, hundredths, and so on.

One of the first computers was the electronic analog computer. It represents information with voltages, which vary continuously. Most computers today are digital, representing information discretely. They use a binary (two-step) system that represents each piece of information as a series of zeroes and ones.

Both computer types have advantages. Digital computers manipulate most data more easily. Because digital information is discrete, it can be copied exactly, whereas making exact copies of analog information is difficult. Analog computers excel in solving differential equations and are faster than digital computers. The Vertical Motion Simulator (VMS) uses an analog computer with the control loader because computing speed is critical in real-time simulation of flight controls.

+ Back to Top


FirstGov - Your First Click to the US Government
+ Freedom of Information Act
+ Budgets, Strategic Plans and Accountability Reports
+ The President's Management Agenda
+ NASA Privacy Statement, Disclaimer,
and Accessibility Certification

+ Inspector General Hotline
+ Equal Employment Opportunity Data Posted Pursuant
to the No Fear Act

+ Information-Dissemination Priorities and Inventories
NASA - National Aeronautics and Space Administration
Curator: Victoriana Delossantos
NASA Official: Wardell Lovett
Last Updated: November 26, 2007
+ Contact Us