Talk:Rotary encoder

From Wikipedia, the free encyclopedia

[edit] simple two-channel

This article needs more coverage of the simplest case -- show the innards of a standard computer mouse, and show the two-channel encoding and explain how it works, how the counters are interfaced. This article needs to be a tech support base for the mouse articles.-69.87.203.252 13:45, 20 March 2007 (UTC)

Yes. Anybody have a good, clear photo of the inside of an optical encoder? I put up a photo of a Hall-effect quadrature encoder (yes, that really is a quadrature encoder), but that's a sealed unit and you can't see how it works. --John Nagle (talk) 04:53, 11 December 2007 (UTC)

[edit] Encoder Disk Image

Is this image right? I think that there is something wrong with the numerical sequence: 0,1,3,2,6,7,5,4. Where did this image come from?--Drvanthorp 16:21, 5 September 2007 (UTC)

[edit] Items that need coverage

A few items that need coverage:

• The "once per turn" signal on an encoder is called an "index pulse". It's not enough for absolute positioning. It's usually used in conjunction with some other means of low-accuracy position sensing, like a limit switch. In such systems, startup calibration involves moving to a limit switch, then back to the next index pulse point.
• Brush-type encoders are rare today.
• Some "incremental encoders" are unidirectional, with only one Hall sensor. Automotive speedometer and tachometer inputs are single-sensor encoders, usually called tachometer sensors.
• Sometimes a resistive position sensor and an encoder are combined into a single unit, to obtain a position at startup. Automotive steering position sensors work this way. —Preceding unsigned comment added by Nagle (talk • contribs) 16:27, 10 December 2007 (UTC)