On Wed, Nov 17, 2021 at 3:07 PM theman whosoldtheworld <bleachk...@gmail.com> wrote:
> wow movelt ..... and there are some ethercat connection on movelt? thanks a > lot > As you plow through the stacks of documentation, you find that MoveIt outputs a "joint trajectory" Which is a set of messages with (time, x, x', x'') The hardware interface is up to the user. MoveIt stops short of the device drivers. This is why I said a hybrid with LCNC might be interesting. LCNCis goodat low levelmotor control andhas the Mesa FPGA ecosystem that work very well. MoveIt is complex and has a really steep learning curve. It is built on top of ROS and ROS has a steep learning curve. I'd guess the stack is a couple orders of magnitude more complex than LCNC. It all runs on Linux and if you are not a Linux software developer then you have ever more to learn. It takes most new people about a year to come up to speed. A Movit-based 6-DOF robot arm is a tough introduction. You are best off starting with basic ROS tutorials and making system that can print "Hello World" to the screen. Also note the current transition from ROS-1 to ROS-2. New projects really should be using ROS-2. So check that you are reading the correct tutorials. Many are not labeled 1 or 2 because there was no need back when only ROS-1 existed. So look for explicit labeling as "2". > > Il giorno mer 17 nov 2021 alle ore 18:22 John Dammeyer < > jo...@autoartisans.com> ha scritto: > > > Very cool. Thanks for the link. > > John > > > > > -----Original Message----- > > > From: Chris Albertson [mailto:albertson.ch...@gmail.com] > > > Sent: November-17-21 8:45 AM > > > To: Enhanced Machine Controller (EMC) > > > Subject: Re: [Emc-users] LinuxCNC with Robot Arm Setup > > > > > > If you are taking the right approach or not depends on the tasks you > want > > > this robot arm to reform. Are they entirely scripted such that you can > > > write G-code to control the arm? Or is this arm using a camera and > > vision > > > system to pick up randomly placed objects? > > > > > > If the former, LCNC will work fine and self-collision is a > > > non-issue because you programmed the G-code so as not to let that > happen. > > > But if the arm's path through space is determined in real-time and is > not > > > pre-programmed, LCNC is not the best tool, and you should be looking at > > > "MoveIt". https://moveit.ros.org/ > > > > > > But I think it is possible to build a hybrid system that uses BOTH > > software > > > systems. There is a part of LCNC that does motion control and has > > > programmatic API and this could be used to build an arm controller. > > MoveIt > > > then computes a trajectory. > > > > > > For LCNC experts not familiar with MoveIt... MoveIt outputs a series > of > > > "target points". for each motor. A joint has the following information > > > > > > - Time this target point shall be reached > > > - The location of the point > > > - The velocity > > > - The acceleration > > > > > > Question. Given that you have a user space process running that has > that > > > above information how to best pass this to LCNC so that LCNC can output > > the > > > stepper pluses or whatever is needed to drive the hardware. > > > > > > On Tue, Nov 16, 2021 at 9:12 PM Ian Charnas <ian.char...@gmail.com> > > wrote: > > > > > > > Hi everyone. I'm new to LinuxCNC but I'm an engineer with a > background > > in > > > > software and cnc machining so I'm hoping I'll learn quickly. > > > > > > > > I'm interested in setting up LinuxCNC to run a robot arm. From what I > > can > > > > tell, the wise approach is to follow this guide > > > > <http://linuxcnc.org/docs/2.8/html/motion/dh-parameters.html> to > > setting > > > > up > > > > my modified DH parameters, and to use this guide > > > > <http://linuxcnc.org/docs/2.8/html/gui/vismach.html> to setting up a > > > > visual > > > > representation of the arm - either by importing STL files or by > drawing > > > > graphics primitives. > > > > > > > > My first question: am I heading down a wise path or are there other > > > > better options that I'm unaware of? > > > > > > > > My second question: Can LinuxCNC prevent the robot arm from crashing > > into > > > > itself, and if so how does it know when a crash would occur? Does it > > use > > > > the geometry of each link that I provide in vismach? > > > > > > > > many thanks for any tips and advice, > > > > Ian > > > > > > > > -- > > > > Ian Charnas | Engineer | iancharnas.com <http://www.iancharnas.com> > > > > > > > > _______________________________________________ > > > > Emc-users mailing list > > > > Emc-users@lists.sourceforge.net > > > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > > > > > > > > > -- > > > > > > Chris Albertson > > > Redondo Beach, California > > > > > > _______________________________________________ > > > Emc-users mailing list > > > Emc-users@lists.sourceforge.net > > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > > > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > -- Chris Albertson Redondo Beach, California _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
