On Sun, 9 Feb 2014, bruno wrote: > Date: Sun, 09 Feb 2014 20:43:14 +0100 > From: bruno <br...@tinkerbox.org> > Reply-To: "Enhanced Machine Controller (EMC)" > <emc-users@lists.sourceforge.net> > To: emc-users@lists.sourceforge.net > Subject: Re: [Emc-users] mesa 5i25, pncconf working but not linuxcnc > > > I played with those values, setting stepgen.maxvel and maxaccel to 0 > like the doc says in order to not limit it. Not much improvement. Then I > tried to increase vastly the MIN_FERROR, and that allows to go through > but I get some occasional grinding noise (missed steps I think) when > doing a test (back and forth on one axis)
setting stepgen_maxxacel to 0 is _not_ reccomended, set it to about 25% more than the axis maxaccel > > One thing I noticed is that the .hal file written by pncconf does not > specify the servo_base_period on the EMCMOT line. > It should not specify a base thread at all a base thread is not needed or desired > What is infuriating is that within pncconf, I can test one axis with > fast movement back and forth and it is real nice, smooth, no missed steps... > > Is there a way to find out which exact parameters pncconf is using when > it launches the tuning applet ? halcmd show param > > On 2/9/14 5:25 PM, bruno wrote: >> >> This is a stepper system, trivkins, 3 axis mill. >> I kind of assumed that the tuning in pncconf is using the >> configuration that it will write, it's not very useful if one tunes >> things but then the parameters to use are different... >> >> so you are referring to these >> >> * >> >> /STEPGEN_MAXACCEL = 21.0/- Acceleration limit for the step >> generator. This should be 1% to 10% larger than the axis >> MAX_ACCELERATION. This value improves the tuning of stepgen's >> "position loop". If you have added backlash compensation to an >> axis then this should be 1.5 to 2 times greater than MAX_ACCELERATION. >> >> * >> >> /STEPGEN_MAXVEL = 1.4/- Older configuration files have a velocity >> limit for the step generator as well. If specified, it should also >> be 1% to 10% larger than the axis MAX_VELOCITY. Subsequent testing >> has shown that use of STEPGEN_MAXVEL does not improve the tuning >> of stepgen's position loop. >> >> looking at the hostmot driver >> >> * >> >> /maxaccel/- (Float, RW) Maximum acceleration, in position units >> per second per second. If set to 0, the driver will not limit its >> acceleration. >> >> * >> >> /maxvel/- (Float, RW) Maximum speed, in position units per second. >> If set to 0, the driver will choose the maximum velocity based on >> the values of steplen and stepspace (at the time that maxvel was >> set to 0). >> >> seems like it would be best to specify 0 for both of those as the per >> axis limits would still be in place ? >> I am going to play with that and see... thanks for the reply >> >> On 2/9/14 4:04 PM, emc-users-requ...@lists.sourceforge.net wrote: >>> Date: Sun, 9 Feb 2014 15:03:40 +0000 >>> From: andy pugh<bodge...@gmail.com> >>> Subject: Re: [Emc-users] mesa 5i25, pncconf working but not linuxcnc >>> To: "Enhanced Machine Controller (EMC)" >>> <emc-users@lists.sourceforge.net> >>> Message-ID: >>> <CAN1+YZV2iQb-AQmWE4TYbxithWSFmSvuMRP-kxk8=jhwpjd...@mail.gmail.com> >>> Content-Type: text/plain; charset=ISO-8859-1 >>> >>> On 9 February 2014 11:30, bruno<br...@tinkerbox.org> wrote: >>> >>>>> After configuring, I started linuxcnc (with tklinuxcnc as I have opengl >>>>> issues with axis right now), and it immediately gives me joint following >>>>> errors. No move, nothing. >>> It might be that Pncconf doesn't teack following error, or has higher >>> limits. >>> >>> However, if this is a stepper system then "following error" means >>> something slightly different to what it means in a servo system. It >>> means that the system has not been able to make the number of steps >>> requested. >>> >>> What this typically means is that the system stepgen accelleration >>> numbers are bigger than the step generator limits. Have a look through >>> your INI file and check that the step-generator accel limits are "a >>> bit" higher than the system and axis limits. >>> >>> Is the machine a gantry system? The other possibility is that the >>> step-generator feedback is going to the wrong axis. >>> >>> -- atp If you can't fix it, you don't own it. >>> http://www.ifixit.com/Manifesto >> > > ------------------------------------------------------------------------------ > Managing the Performance of Cloud-Based Applications > Take advantage of what the Cloud has to offer - Avoid Common Pitfalls. > Read the Whitepaper. > http://pubads.g.doubleclick.net/gampad/clk?id=121051231&iu=/4140/ostg.clktrk > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your (")_(") signature to help him gain world domination. ------------------------------------------------------------------------------ Managing the Performance of Cloud-Based Applications Take advantage of what the Cloud has to offer - Avoid Common Pitfalls. Read the Whitepaper. http://pubads.g.doubleclick.net/gampad/clk?id=121051231&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
