THE WHATIS.COM WORD-OF-THE-DAY March 27, 2002 stepper motor ______________ TODAY'S SPONSOR: VeriSign - The Value of Trust
Secure your servers with 128-bit SSL encryption! Grab your copy of VeriSign's FREE Guide, "Securing Your Web site for Business," and you'll learn everything you need to know about using 128-bit SSL to encrypt your e-commerce transactions, secure your corporate intranets and authenticate your Web sites. 128-bit SSL is serious security for your online business. Get it now! http://WhatIs.techtarget.com/r/0,,2594,00.htm?VeriSign ______________ TODAY'S WORD: stepper motor See our definition with hyperlinks at http://whatis.techtarget.com/definition/0,,sid9_gci812430,00.html A stepper motor is a special type of electric motor that moves in increments, or steps, rather than turning smoothly as a conventional motor does. The size of the increment is measured in degrees and can vary depending on the application. Typical increments are 0.9 or 1.8 degrees, with 400 or 200 increments thus representing a full circle. The speed of the motor is determined by the time delay between each incremental movement. Inside the device, sets of coils produce magnetic fields that interact with the fields of permanent magnets. The coils are switched on and off in a specific sequence to cause the motor shaft to turn through the desired angle. The motor can operate in either direction (clockwise or counterclockwise). When the coils of a stepper motor receive current, the rotor shaft turns to a certain position and then stays there unless or until different coils are energized. Unlike a conventional motor, the stepper motor resists external torque applied to the shaft once the shaft has come to rest with current applied. This resistance is called holding torque. Stepper motors are used in computer hard drives, because they can be moved and positioned with precision. They are also used in various robotic devices, and as antenna rotators. RELATED TERMS: current http://whatis.techtarget.com/definition/0,,sid9_gci211871,00.html robot http://whatis.techtarget.com/definition/0,,sid9_gci519835,00.html antenna http://searchnetworking.techtarget.com/sDefinition/0,,sid7_gci211571,00.html ______________________ SELECTED LINKS: Euclid Research defines some characteristics of stepper motors. http://www.euclidres.com/apps/stepper_motor/stepper.html Techlib.com offers some stepper motor experiments and projects. http://www.techlib.com/electronics/stepper.html ______________________ QUIZ #23 | Firewalls Our latest quiz tests your knowledge about the mighty firewall. How much do you really know about this useful set of related programs? We invite you to find out! http://whatis.techtarget.com/definition/0,,sid9_gci811182,00.html ______________________________ CRITICAL SECURITY TIPS, TACTICS & TECHNIQUES - FREE It's fairly simple: If something goes wrong with your current security infrastructure, and you're on the hook to face the consequences, it won't be pretty. Don't go it alone! Stop the threat of a hack attack with expert tips, tactics and techniques at the FREE Security Decisions conference June 19-21 in Chicago, hosted by SearchSecurity. Full conference benefits at: http://ad.doubleclick.net/clk;4012996;5058249;p?http://www.securityconf.com/html/registration.htm ______________________________ RECENT ADDITIONS AND UPDATES [1] picofarad per meter http://whatis.techtarget.com/definition/0,,sid9_gci812011,00.html [2] Nyquist Theorem http://whatis.techtarget.com/definition/0,,sid9_gci812005,00.html [3] coulomb per centimeter squared http://whatis.techtarget.com/definition/0,,sid9_gci811193,00.html [4] optical disc http://searchstorage.techtarget.com/sDefinition/0,,sid5_gci811276,00.html [5] data preprocessing http://searchdatabase.techtarget.com/sDefinition/0,,sid13_gci810056,00.html ____________________________________________________________________ ::::::::::::::::::: WHATIS.COM CONTACTS ::::::::::::::::::: LOWELL THING, Site Editor ([EMAIL PROTECTED]) ____________________________________________________________________ MARGARET ROUSE, Assistant Editor ([EMAIL PROTECTED]) ___________________________________________________________________ :::::::::::::::::::: ABOUT THIS NEWSLETTER ::::::::::::::::::::: Created by TechTarget (http://www.techtarget.com) TechTarget - The Most Targeted IT Media Copyright 2002, All Rights Reserved. If you would like to sponsor this or any techtarget newsletter, please contact Gabrielle DeRussy at [EMAIL PROTECTED] If you no longer wish to receive this newsletter simply reply to this message with "REMOVE" in the subject line. Or, visit http://WhatIs.techtarget.com/register and adjust your subscriptions accordingly. If you choose to unsubscribe using our automated processing, you must send the "REMOVE" request from the email account to which this newsletter was delivered. Please allow 24 hours for your "REMOVE" request to be processed.
