ROBOTIC ARM MILLING FOR SCULPTURE

[marek]

This may seem a strange request, but I am looking into digital created sculpture, the intention to use my 3d graphical experience to create STL 3d files, primarily of people  as the intial source. My background is also Holography, photography  and other 3d imaging technologies, although primarily I am a software developer.  I also have a passion for art.
 
I have been looking at stereolithography and 3d printers, cnc routing in polyurethane and polystyrene, metals, clay, aluminium and other materials. 
The current method for sculpture, apart from the traditional methods (many weeks/months of hard work)  is to create 3d graphic files (STL) using Maya, Z-brush, Photoshop, Autocad, 3Dmax etc, to slice the object into reasonably sized parts, cnc machine into polystyrene, polyeurothane, MDF  or other materials, reassemble, spray paint with clay, finished and later used as the source for casting into bronze or other materials. Most successful sculptors use this technology but do not admit to it. For a full human size object, outsourced could cost something in the region of 2-5000  GBP and a further  5000 GPB or so for metal casting like bronze or aluminium.   
 
Ideally I am looking at using the robotic arm for milling (RMC I think it is called) in materials like polymer clay, polystyrene, polyurethane  or other "soft" substances, maybe sandstone and stone composites. No idea of the payload required, and I am not sure what this actually means. I guess I am not looking for a massive robotic arm, like some of the Kukas I have seen, possibly something along the same lines as Universal Robots (Denmark)  6 axis arm  which is much smaller.  The maximum size of the final parts would be 70-80cm or so, ideally from a stl file, ply or obj source.  Any guidance would be much appreciated as I am a total blockhead in the field of technology. 

What I am looking for is something like the following URL's:-
 
<a href="http://www.youtube.com/v/UjMJOfCyDaA&rel=0" target="_blank">http://www.youtube.com/v/UjMJOfCyDaA&rel=0</a>
 
http://www.cadinfo.net/art/robotic-sculpture

Appreciate your help

[Industrialrobotix]

Check with the guys at Global Robots - www.globalrobots.com - they are friends of mine - they have a post processor written for ABB robots from a 3D CAM package - it could work for you however depending on the robot or the size of the post file you may have to figure out how to drip feed the program into the robots...  You will have to work with them to develop the post to run a 7th axis for the turn table as well...

[Robotter]

Hello Marek:

Could you let me know your geographical location?

[SkyeFire]

The system used to carve that Beethoven bust in the demo video (I think I was there for that) was KUKA's CAMRob, which translates a standard 3D CAD/CAM file into KRL program code.

Alternatively, I know some forumites have talked about using a system called RoboMaster to good result, although I don't know anything about it myself.

Robot payload will depend partly on the weight of your end effector (probably not a lot for this application), the hardness of the material you're working with, and the speed you are trying to work it with.  Those last two will determine how much force the robot has to apply and withstand during your process.  A KR16 might not quite cut it -- generally the larger robots are more rigid.  But a KR500 would be gross overkill.  The robot in the video looks like a KR240 with an arm extension, which seems to be the general "workhorse" of the current KUKAbot generation.

[marek]

Hello Marek:

Could you let me know your geographical location?

I am based in London, United Kingdom

[TylerRobertson]

Alternatively, I know some forumites have talked about using a system called RoboMaster to good result, although I don't know anything about it myself.

Guess I have to chime in here, haha
This kind of work is exactly what robotmaster was designed for - it is a total conversion software for the popular CNC machining software Mastercam

so far, it can do two coordinated rotary axes for through cut programming, or indexing, and 3 coordinated gantries.
The toolpath programming in Mastercam is relatively standard, but does require training/time to use it really well if you don't have any machining experience, but it's one of the easier to use/user friendly CNC machining softwares.

Robotmaster then does the processing on the 3-5 axis toolpaths, and allows for 6+ axis control.
Like Skyefire said - you can develop a post-processor to convert CNC code to robot native code (that's where Robotmaster started years ago), but that would only be really sufficient if you're always doing roughly the same cutting path. A straightforward post-processor won't allow you to have much if any control over the robot orientation (the robot will be locked to a certain angle through a toolpath), as well it won't check for any errors relating to the robot kinematics.

For this type of work to operate really effectively you need to error check the program against the robot kinematics, and allow for a change in robot orientation. If I had to do this without Robotmaster, you'ed be looking to get:

A mid to high end CAD/CAM machining software, capable of 3 to 5 axis machining. (Mastercam, Surfcam, Delcam, etc.)
Some kind of postprocessor to make it generate robot code
Simulation software for whatever robot you're running


If you're looking for more info, just send in a request on www.robotmaster.com - it'll be picked up by my colleagues and they're all great people

[RoboticCNC]

SkyeFire,

I have to take exception to your comment that the Behtoven Bust was cut using CamRob. That is not true.

My Company, Robotic Solutions, Inc. installed that robot out in California about 2 years ago. I personally wrote the toolpaths and run the program for one of thier open houses.

We offer a product for converting PowerMILL code to unlimited size KRL code for Kuka robots. The product is called CodeBreaker.

Tom

[TylerRobertson]

Tom - I should have caught that he said CamRob - I thought maybe you did a CamRob simulation with it as well.

Between that video and the video of the ABB robots carving milling - people are starting to see a different side of robots as material removal tools

[SkyeFire]

Hm.  The reason I said that is b/c I once saw, about two years ago, that same Beethoven bust (or a very good likeness) being carved out of foam by a KUKA robot running CAMRob.

Still, that's not so startling, if the design file for the bust was an open STL file.  Someone whose RepRap blog I follow has been testing his 3D-printing software by printing an open-source STL file of a nude female figure.   

http://technocraticanarchist.blogspot.com/2010/03/printing-naked-lady-with-slice-and-dice.html

And a (not the) Beethoven bust, by way of example:  http://www.thingiverse.com/thing:1178

[TylerRobertson]

I'm sure could have been someone from Kuka running Tom's SRC code through CamRob making themselves look sharp  

[SkyeFire]

   Why would they?  As far as I know, CAMRob is entirely capable of performing that operation.  The only "odd" thing is that the original CAD files for the two busts must have been very similar, if not identical, but as I pointed out earlier, there's several possible explanations for that.

[robocam.com.au]

Marek,

There are some great products out there, Robotmaster, Code Breaker etc. etc. However when we kicked off all of these were a little too expensive for us. The robot was purchased new and the job we had to pay for it all fell through. Rather than end up with a 1 ton brick we wrote some software ourselves.

We have a Motoman HP165 that has a 2.5m reach and a 165kg payload. On that is mounted a 5hp 28000rpm manual ER25 collet spindle motor.

Using the CNC tool kit (http://www.cnc-toolkit.com/) and a custom written post processor we can cut very complex shapes in foam and wood to close tollarences etc.

For your application (small work pieces 1m tall) buy a new or low hour HP20 or 40 with an NX controller. Bolt on a pheumatic spindle (they're light and fast) Download the CNC tool kit and I'll sell you our postprocessor for $5k USD.

Take a look at this video  <a href="http://www.youtube.com/v/QI0E8QZBd9U&rel=0" target="_blank">http://www.youtube.com/v/QI0E8QZBd9U&rel=0</a>  this is what you can acheive with the smaller robot. This company (tromes design in Perth WA) uses Delcam PowerMill but the results are the same as with the CNC tool kit. Alternatively we also have a Powermill post processor we wrote for another coustomer.

We provide full instructions and our software will also help you set the robot userframes just like zeroing a CNC machine.

Cheers,

Adrian
www.RoboCAM.com.au
Sydney, Australia

[Domonoky]

A bit offtopic, but as i saw the model of the naked lady in this video. It reminded me of what i printed a few weeks ago on my 3dprinter. :-)
 
http://picasaweb.google.de/Domonoky/repman#5450734932975686482 and http://picasaweb.google.de/Domonoky/repman#5450735189537858162

[robocam.com.au]

BTW,

We also wrote a post processor for sheetcam and use it to plasma and water jet cut sheet steel and alum. using our Motoman HP165. Sheetcam costs about $150! http://www.sheetcam.com.

regards,

Adrian

[lizydude]

You just need a prototype machine to have some of those things. A better machine could create a better prototype. I am wondering if you need a 3d printers too here.