This offset approach is proving harder than I expected. I think it is because I'm using the PID-driven stepgen approach generated by pncconf (7i92 board). The original relevant hal logic is:
net t-pos-cmd => pid.t.command net t-vel-cmd => pid.t.command-deriv net t-pos-fb => pid.t.feedback net t-output => pid.t.output net t-pos-cmd <= joint.0.motor-pos-cmd net t-vel-cmd <= joint.0.vel-cmd net t-output <= hm2_7i92.0.stepgen.00.velocity-cmd net t-pos-fb <= hm2_7i92.0.stepgen.00.position-fb net t-pos-fb => joint.0.motor-pos-fb Putting offset into the position command and position feedback nets gives: net t-pos-cmd-off => pid.t.command net t-vel-cmd => pid.t.command-deriv net t-pos-fb => pid.t.feedback net t-output => pid.t.output net t-offset motion.analog-out-00 net t-offset offset.0.offset net t-pos-cmd <= joint.0.motor-pos-cmd net t-pos-cmd => offset.0.in net t-pos-cmd-off <= offset.0.out net t-vel-cmd <= joint.0.vel-cmd net t-output <= hm2_7i92.0.stepgen.00.velocity-cmd net t-pos-fb <= hm2_7i92.0.stepgen.00.position-fb net t-pos-fb => offset.0.fb-in net t-pos-fb-off <= offset.0.fb-out net t-pos-fb-off => joint.0.motor-pos-fb I think the velocity gets messed up by the step function in position, and the pid loop is using velocity. Any further suggestions for achieving my invisible 90 degree rotations? Thanks again, -- Ralph ________________________________________ From: Ralph Stirling [[email protected]] Sent: Thursday, March 15, 2018 11:29 AM To: Enhanced Machine Controller (EMC) Subject: Re: [Emc-users] joint/axes question (2.8-pre) I like that. I can't do it in world mode because tan(pi/2) is a problem... Offset is a real clean solution. -- Ralph On Mar 15, 2018 11:06 AM, andy pugh <[email protected]> wrote: On 15 March 2018 at 17:56, Ralph Stirling <[email protected]> wrote: > I would like to be able to rotate the table a 1/4 turn > after each job is run. Ideally, I would love to just switch > from world to joint (teleop) mode with a G code, but that > doesn't seem to be an option You could use the offset HAL component between joint.0.motor-pos-cmd and the stepgen/pid. Then the kinematics would have no idea that the rotary had moved. Drive the offset with a G-code analogue out. -- atp "A motorcycle is a bicycle with a pandemonium attachment and is designed for the especial use of mechanical geniuses, daredevils and lunatics." — George Fitch, Atlanta Constitution Newspaper, 1916 ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
