Glass scale is THE solution for really high precision. (this remove ball screws geometric error, as well as mostly all flexure error). Unfortunately, it is usually not possible to get a good servo loop with the linear glass directly, thus an encoder on the motor is still needed (mostly to have a wide bandwidth on the servo loops control). Basically, the concept is to use the motor encoder for high frequency information (Derivative term of the PID), and the glass scale for the Integrator term. Things start to get complex for the P term.. it may be a mix of both, or different algorithm... this is upon the bandwidth wanted and geometrics of the machine.
Le 22.05.2012 15:43, [email protected] a écrit : > Are there any major dis-advantages to using glass scales as position > feedback for a servo system versus using encoders directly attached to the > motors. I could see where backlash might be an issue but if using precision > ground ballscrews........ > ------------------------------------------------------------------------------ > Live Security Virtual Conference > Exclusive live event will cover all the ways today's security and > threat landscape has changed and how IT managers can respond. Discussions > will include endpoint security, mobile security and the latest in malware > threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
