Nobody objects to the concept of distributed motion control. The Machinekit fork of LinuxCNC has progressed farther along that path. EtherCAT itself poses some of its own issues, with expensive slave devices and intellectual property issues with the protocol and custom hardware to implement the protocol. LinuxCNC solves a great many real-world problems with low cost, relatively generic hardware, so most users have not felt a great need for distributed control like EtherCAT. There have been people who demonstrated LinuxCNC interoperability with EtherCAT in the past though. If you google "linuxcnc ethercat" you will find references in the wiki:
http://wiki.linuxcnc.org/cgi-bin/wiki.pl?EtherCatDriver videos: https://www.youtube.com/watch?v=yR9rCFavFjU and on the developer's email list: http://comments.gmane.org/gmane.linux.distributions.emc.devel/10720 So it is an idea that has been around for years. -- Ralph ________________________________________ From: Nicklas Karlsson [[email protected]] Sent: Friday, March 11, 2016 10:48 AM To: Enhanced Machine Controller (EMC) Subject: Re: [Emc-users] New protocol --> reduced real time demand Then I have to assume no one have any complaints about the idea. On Fri, 11 Mar 2016 11:28:07 -0600 John Thornton <[email protected]> wrote: > Nope it is still there... > > On 3/11/2016 11:02 AM, Nicklas Karlsson wrote: > > I posted earlier to EMC developers but it seems to have disappeared. > > > > I have been thinking about a new protocol. Ethercat are a perfect real time > > network there data is inserted while packet is pass thru, actually it is > > very similar to cascaded shift registers although CRC is also added. I have > > not studied protocol yet but this kind of network it should be possible to > > put node sourcing/sending data at any node or vary number of nodes with > > exactly the same message circulating the network. It would however be > > possible to achieve something similar for data sent from linuxcnc if > > multicast is used although only for outputs. > > > > I would propose to put axis position control at motor controller, > > advantages: > > 1. Motion control would be reduced towards youtube style real time demand > > since positions could be sent beforehand and buffered. > > 2. Position control could be sent to all nodes with one multicast message. > > 3. If interpolation is used it would be possible to reduce number of > > messages. > > 4. Divide outputs between several nodes would only affect real time > > performance for hopefully slow feedback. > > > > Problem would still be the same with inputs although I think most of them > > have less demand on response time. > > > > > > Nicklas Karlsson > > > > ------------------------------------------------------------------------------ > > Transform Data into Opportunity. > > Accelerate data analysis in your applications with > > Intel Data Analytics Acceleration Library. > > Click to learn more. > > http://pubads.g.doubleclick.net/gampad/clk?id=278785111&iu=/4140 > > _______________________________________________ > > Emc-users mailing list > > [email protected] > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > ------------------------------------------------------------------------------ > Transform Data into Opportunity. > Accelerate data analysis in your applications with > Intel Data Analytics Acceleration Library. > Click to learn more. > http://pubads.g.doubleclick.net/gampad/clk?id=278785111&iu=/4140 > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ Transform Data into Opportunity. Accelerate data analysis in your applications with Intel Data Analytics Acceleration Library. Click to learn more. http://pubads.g.doubleclick.net/gampad/clk?id=278785111&iu=/4140 _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ Transform Data into Opportunity. Accelerate data analysis in your applications with Intel Data Analytics Acceleration Library. Click to learn more. http://pubads.g.doubleclick.net/gampad/clk?id=278785111&iu=/4140 _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
