Hi Yishin,
actually in this case (emccanon.cc) it is correct.
The calculations you are looking at are for the X axis. The X axis is the same
no matter what machine you have.
It is further down (in the motion controller, trajectory planner) that this X
move would have to be scaled further based on _joints_ limits.
Regards,
Alex
----- Original Message -----
From: Yi-Shin Li
To: EMC developers
Sent: Sunday, November 08, 2009 2:01 PM
Subject: Re: [Emc-developers] the trajectory planner might not be
suitableforany machines with non-trivial kinematics
Hi Alex,
I've pulled the joints_axes3 branch, built and tried it.
In this branch, the getStraightVelocity() and getStraightAcceleration()
on emccanon.cc are not suitable for non-trivial kinematics yet.
I will file a feature request on SourceForge later.
Regards,
Yishin
On Thu, Nov 5, 2009 at 2:22 AM, Alex Joni <[email protected]> wrote:
Hi Yi-Shin,
unfortunately you are correct.
There are some problems in the current version of emc2, that joints
(motors) and axes (carthesian directions) are mixed in a couple of places.
There is ongoing work (on the joints-axes3 branch) to fix this.
But it's a lot of work (in a lot of layers and places), so there is no
fixed timeline when it will be useable.
Regards,
Alex
From: Yi-Shin Li
Sent: Wednesday, November 04, 2009 6:13 PM
To: emc-developers
Subject: [Emc-developers] the trajectory planner might not be suitable
forany machines with non-trivial kinematics
Hello emc-developers,
I was digging into an issue for SCARA Robot controlled by EMC2. That is,
the angular acceleration for the first 2 joints is way too larger than the
one
set by its configuration file. After carefully analyzing the dumped trace,
I found it might be caused by misleading trajectory planning results.
I then found an interesting issue for the trajectory planner, i.e. it might
not
be suitable for any machines with non-trivial kinematics. Please take a
look for the following code at getStraightAcceleration() on emccanon.cc:
tx = dx? (dx / FROM_EXT_LEN(AXIS_MAX_ACCELERATION[0])): 0.0;
For non-trivial kinematic machines, such as SCARA, the dx is contributed by
several joints other than AXIS_0. However, the above code assume that
it only depends on AXIS_0, which is not true for those machines. Therefore,
the calculated accel/velocity for trajectory planner may be incorrect.
Is my understanding for above statement correct?
Yishin
----------------------------------------------------------------------------
------------------------------------------------------------------------------
Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day
trial. Simplify your report design, integration and deployment - and focus
on
what you do best, core application coding. Discover what's new with
Crystal Reports now. http://p.sf.net/sfu/bobj-july
----------------------------------------------------------------------------
_______________________________________________
Emc-developers mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/emc-developers
----------------------------------------------------------------------------
No virus found in this incoming message.
Checked by AVG - www.avg.com
Version: 8.5.424 / Virus Database: 270.14.48/2479 - Release Date: 11/03/09
19:38:00
------------------------------------------------------------------------------
Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day
trial. Simplify your report design, integration and deployment - and focus
on
what you do best, core application coding. Discover what's new with
Crystal Reports now. http://p.sf.net/sfu/bobj-july
_______________________________________________
Emc-developers mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/emc-developers
------------------------------------------------------------------------------
------------------------------------------------------------------------------
Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day
trial. Simplify your report design, integration and deployment - and focus on
what you do best, core application coding. Discover what's new with
Crystal Reports now. http://p.sf.net/sfu/bobj-july
------------------------------------------------------------------------------
_______________________________________________
Emc-developers mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/emc-developers
------------------------------------------------------------------------------
Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day
trial. Simplify your report design, integration and deployment - and focus on
what you do best, core application coding. Discover what's new with
Crystal Reports now. http://p.sf.net/sfu/bobj-july
_______________________________________________
Emc-developers mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/emc-developers
