[puma560]

Hi all. I'm new to CNCzone so sorry if this has been covered before...


I have a Unimation Puma 560 robot arm. I don't have a working controller for it so I'd like to make a new one that can be controlled from a pc. I've been looking through the threads and it seems that a UHU controller with 'Robot Assist' from Kinematics.com may be a way forward.

Has anyone done this? Or something else?


The Puma has 6 axis, each with a 48V dc motor and incremental encoder.

Also, does anyone know the web address for UHU controllers?

Thanks

Jonathan (London UK)

[keithorr]

I googled UHU controller and got http://gsst.wikispaces.com/ with links to plans, parts and complete controllers.

[puma560]

Thanks Keith - that's great.

Another couple of questions for you all...

The Puma has quadrature encoders that provide sine/cos differential (A+ and A- and B+ and B-) outputs. I understand the UHU needs a 5v square wave A and B for encoder i/p. Does anyone know a circuit to convert the differential analogue signals to nice logic ones?

Also, I've been looking at the Mech software. Does anyone know if this is suitable for an arm robot or just for milling machines?

Thanks

Jonathan

[keithorr]

I'm not sure of the vocabulary; sine, cos, square wave...

Some machines need quadrature and some only use the A,B and maybe an index (Z).

I'll bet 20p you only need to ignore the A-,B- connections. Can you post an image that shows the particular a portion of the schematics involved?

Find member "Al the Man" and ask him. He knows all that.

[unterhaus]

there are converter boxes from Heidenhain and others to convert the analog (sin/cos) quadrature encoder signals to square wave. They are often called interpolation circuits because there is more information in sin/cos than there is in a square wave. You might look at EMC, there was kinimatics for a Puma in there at one time.

[puma560]

Hi all. I've found a way to convert the differential analogue encoder signals to square waves. All you do is feed the output of the encoder (A+ and A-) into the two inputs of an op-amp, supply the op-amp with 5V and, bingo, you get a square wave on the o/p. Do this for both the A and B channels and away you go....

Jonathan

[Coogrrr]

couldnt you hookup a xylotex controller and be done with this?

2 of the 3 axis units for 6axis control

www.xylotex.com

??

[unterhaus]

this robot is not using steppers. I have never seen an industrial robot that used steppers, not that you couldn't make a small one. Don't think the customers would buy it. You could not move a robot that size successfully for very long with a xylotex

[interflexo]

Hi,

I would go with a Delta Tau controller.

Features useful for your project:

4096x sinusoidal encoder interpolation
Real-time multi-tasking operating system
Choice of PC based or standalone terminal operator interface
User-written forward and inverse-kinematic algorithms for non-Cartesian geometries

Best Regards,

Manuel

[puma560]

Hi Interflexo. The Delta Tau looks intersting. The problem I have is a lack of software knoledge to control a device like that. I cant find anyone that has written control software for the Puma using such a card....


Jonathan

[GaryCorlew]

Art of mach3 is working on a plugin for delta tau... I think its working but I am not sure of that. Go on the mach3 web site there are forums on there and a yahoo group as well.

[wendy347474]

Hi puma 560 , can you mail me the circuit with the components to square up the sin cos signals from a heidenhain ls 300 scale .
I tried a couple of times, but it doesn't work .
Maybe i use a wrong opamp or something like that .

[CNCZONERAMICO]

I am looking to buy, perhaps build a small stepper robot arm so I can trim complex curved plastic molded parts. Can anyone share any suggestions? Thanks.

[jokaba]

Does anyone know a circuit to convert the differential analogue signals to nice logic ones?

I make this. C U