Wow, building a precision 3d printer is amazingly easy if you can get your hands on an industrial-quality robot arm. [Dane] wrote in to tell us about this huge extruder printer made from an ’80s-era SCARA robot arm. It is capable of printing objects as large as 25″x12″x6.5″.
This 190 pound beast was acquired during a lab clean out. It was mechanically intact, but missing all of the control hardware. Building controllers was a bit of a challenge since the it’s designed with servo motors and precision feedback sensors. This is different from modern 3d printers which use stepper motors and no feedback sensors. A working controller was built up one component at a time, with a heated bed added to the mix to help prevent warping with large builds. We love the Frankenstein look of the controller hardware, which was mounted hodge-podge as each new module was brought online.
You can see some printing action in the clip after the break. A Linux box takes a design and spits out control instructions to the hardware.
since the it’s designed with servo motors and precision feedback sensors. This is different from modern 3d printers which use stepper motors and no feedback sensors.
Closed loop servos with encoders are far superior tolerance wise to steppers.
Modern, TRUE industrial 3d printers also use encoders. It’s mainly the cheap reprap/makerbot style machines that only use steppers.
You need to constantly know where you are and where you are going so you can correct for that in real time.
I have been looking forward to seeing a robot arm 3d printer :)
I’ll second that. It’s good to see someone who didn’t take the ‘easy’ way out. I’ve wanted to do this for years but never had the time / money / hardware to make it happen.
If tuned properly, this type of servo gives you speed, power, AND accuracy all in one go.
GOOD STUFF.
And price. A same strength/speed servo motor is much more expensive then a step motor with the same specs. That’s why RepRap like designs use steppers.
Been thinking for a long time that what we really need is a 3D printable SCARA Robot Arm assembly, so we can get away from these damn cartesian bots.
I love that in the screen shot of the video (and at the beginning of it) it’s a robot arm printing another robot arm. XD
I was sure I had seen
http://singularityhub.com/2012/04/23/3d-printing-robot-produces-chairs-and-tables-from-recycled-waste/
this printer here. I guess maybe I saw the link to the video on another site I frequent.
man where do people buy stuff like this
The robot was free, being thrown out of a laboratory. It’s 1980’s era hardware, similar devices can be found at industrial auctions
-Dane
Is the smiley face a reference to GERTY? If so, that’s just one more awesome thing about this project.
http://www.hgrinc.com/buyOurs/inventory_list.do?searchlog=&sel_word=&sel_word_sub=%27%27&sel_inventory_num=&sch_word_chk=1&sch_word=&sch_word_sub=%27%27&sel_start_dt=&sel_end_dt=&sel_category=00304&sortBy=4&sortYN=1&pageLine=10&sessionUrl_pass=N&viewMode=list&currPage=3&inventory_num=&from_url=%2FbuyOurs%2Finventory_list.do&addList=&cust_id=&sch_yn=Y&buttonView=1&sel_start_price=&sel_end_price=&priceMode=direct
The world is filled with old power hungry robots that no one loves. They’re much, much cheaper than foster children and will work for you night and day.
However, it takes some work to get them usable.
In many cases, the servos are fine, but the control hardware is gone/dead/undocumented and no one wants to mess with it.
I am making the first two lines into a bumper sticker.
That is awesome
just keep in mind: It’s all fun and games until someone loses an eye. :)
Keep an eye on it is a figure of speech meaning watch the machine as it does it’s job. You weren’t suppose to take your eye out and put it on the arm where it will get flung across the shop and lost.
Geez, people with glass eyes take things so literal!
Now that I said something stupid and off the wall;
I feel much better. I guess I needed my daily fix.
only the control system make it pwoer hungry, the power consumption of the rest never really changed.
ok this is cool, now I can build a 3d printer and a robot arm at the same time, and here I was wondering what to do with all these arm’s I keep making.
kb1kanobe: how about we do this with your 10′ welder arm!? >:}
Okay, that’s cool. I’m pretty sure something like this would also be quite readily adaptable to a 3d router.
Sure; Swap out the extruder head for a miller, adjust in software and you’re good to go :)
something like this?
http://transistor-man.com/PhotoSet/roboweld/P1150847.JPG
-Dane
the smiley face is quite anthropomorphic.
The smiley face was a tribute to Gerty, from the movie ‘Moon’
http://hqvoice.com/wp-content/uploads/2011/07/gerty2.png
Holy crap!!! I learned how to do automation with one of those! The elbow direction change was a bitch to program.
Cool!
@ elbow direction:
I haven’t actually solved that part yet in the kinematic model, it ends up working but VIOLENTLY jerking between ‘left’ and ‘right’ forward models. i mitigated it by placing a max-acceleration in that mode, but i’m always open to a more elegant solution.
I may have the source code for that still. It probably got purged during a hard drive swap somewhere along the line. It took a lot of effort to get that one code block to work and we shared it among each other after someone got it working well.
Are you familiar with ikfast? OpenRAVE’s kinematics solver? It should handle it just fine.
I also had big problems with the elbow dirction. But the printer is great.
Matt.
That crazy B-st-rd.
I has been wanting to say that with some of these hacks, but this one takes the cake. My dreams don’t even compare to what some people actually accomplish!
Too Cool!
Now I know what to do with the two IBM 7547 SCARA robots in the basement. Luckily they came with the controls so I don’t have to be as ingenious as Mike.
Sorry Dane – should have given you the credit.
what is the laser for? rangefinding?
Home-ing, i have a target that the robot lines up with to get an absolute home in the x-y direction
This is truly amazing. Can anyone share their Marlin Code and the board type being used? I am looking to make one for myself to experiment with it! amazing concept for the 3d market.
I Also would love the merlin code, Just stumbled on this and its amazing
Robots will be the the Future ! No need for Humans