what software

[erase42]

Hi , Im wondering what software might be available for running a 4 or 5 axis robot arm. Is there some pc based software for this similar to the software for running cnc mills lathes foamcutters etc?

[kaye7877]

I've used a Delta Tau PMAC for this in the past. You can program it for teach mode or use inverse kinematics for tool position.

What kind of system is this?

[unterhaus]

emc will run a robot, but you would need to resurect some code yourself, I believe. The kinematics code can be swapped out, that's the only difference between a robot and a cnc machine.

Someone on CNCzone was using mach. Pre-correcting the kinematics is a reasonably straightforward thing.

[erase42]

Hi Kaye,
Its not really a system that could be labeled, in fact its not built yet. I have the mechanincal ability to make an arm and have already got most of the servo/steppers drivers and gearboxes that I think I would need. Just wondering what good it would do me to build one and if there is some hobby level software out there or some hobbiest developed software that can be used to create usable predictable repeatable movements. I know mach# can control up to 6 axis, but Im wondering about the mathmatics of an arm style robot, with the changing lenghts and radii. I could probably write an excel spreadsheet that would handle the math to define the the relative proportions of movement, but as far as being able to do something useful with that info, like making a workable sculpting tool engraver, im lost. maybe someoen can give me a rundown of how most people control an arm style bot.

thanks

[kaye7877]

I'll make an assumption that you are not defining a path for the 'tool point' to follow. It is quite a bit more difficult to program a path than creating a 'teach point' program. May I suggest progressing this way. I am assuming you will be using servos so you can read the position registers to allow teaching positions.

First, create a system where you can 'teach' the positions of the robot. I have a generic program I have written for many of the Delta Tau products to do this if you end up with that type controller. The cycle with then just move to each position. This will get you moving and may suit your needs.

Second, add a method of handling I/O. Read and write outputs at the end of each move set.

Third, now you can start to think about how you might setup the inverse kinematics of the system. With this information in the controller, you can create offsets from your taught position that should be fairly accurate relative to a coordinate system you define. This is how I chase production parts that I have to weld with a robot arm(parts are measured in the fixture by vision or 'soft tooling'). You can also control the tool point at this level.

Keep building on this if you want. You'll know what you need when you are at this point.

You will be writting this code into the motion controller, like a Galil, PMAC, Aerotek, etc. Probably utilizing a PC for the MMI.

Of course I could be WAY off base from your intentions. Define exacly what you will be doing with the arm and the hardware and I might be able to help you a lot more.

I'm about brain dead tonight, so this post may not make a lot of sense.

[keithorr]

One program for kinematics. One for motion control. Asking your motion control software to do kinematics on the fly is too much. I use Robot Assist. You can download a free sample program (can't save changes) and the useable version is $75.00 (or was). Unsupported software. Incomplete documentation but it does work. Just takes some time and will crash if you confuse it. Still, $75 vs. 10k for WorkSpace.

After the kinematics software spits out the text file of joint angles, you can use any motion software that is appropriate for your machine; # of axis, stepper/servo I/O etc. The joint angles can be read like G code, just more axis.

[pmac_user]

Hi! I'have a Delta Tau PMAC and I'm a neophyte in programming it.
I wish more information about it, or a not dispersive manual.......

[simon1040]

You may find this an interesting article

Using a kuka 5 axis robotic arm and powermill
http://www.powermill.com/news/press_...p?releaseId=28