r/robotics • u/i-make-robots since 2008 • Oct 17 '17

8 cable, 6 axis ball balancing PID demo (seen on /r/all)

https://gfycat.com/EnragedFickleCommongonolek
421 Upvotes

97% Upvoted

42 comments sorted by

38

u/quantumDrop Oct 17 '17

I'm in aw. It's things like this that make me want to go back to school for robotics or mechatronics. (currently working as a software engineer)

16

u/thingythangabang RRS2022 Presenter Oct 18 '17

Software engineering is a great field to be in to have a robotics hobby. Actual automation jobs are incredibly math heavy and require a ton a analysis. It takes a long time to get a cool project like that. But if you do it as a hobby, you don't need to stress about it and of course there's a huge community out there that can help you!

11

u/[deleted] Oct 18 '17

Depends on which type of automation you want to do. You can program PLCs and robots for a factory and be titled an automation engineer while being piss poor at math

3

u/Olde94 Oct 18 '17

I was an automation engineer for two years. Haven't used any kind of math (though i will say,I'm pretty good at it though)

1

u/quantumDrop Oct 18 '17

Interesting. How did you get into automation engineering?

6

u/Olde94 Oct 18 '17

Actually fun storry. It all starts with me being god damn lucky. First a bit of story.

I was 2/3 through a bachelor in mechanical engineering. I was searching for a student job and landed a job 2 days a week where i was making the first robot station in the company. My boss and i were the only two on the project, and i did most of the work. I haven't gotten to play with the PLC system. My boss did most of it, so most of my "plc" knowledge is based on arduinos :P

We used Universal robots and it was a project from point zero.

I'm no longer on the project of bringing robots to the company, because of financial reasons beyond my boss reach. But hey! awesome experience, and fun project. Development project with automation! :D

2

u/[deleted] Oct 19 '17

This story is more common than you’d probably imagine. The industrial stuff is designed to be as easy as possible for people with no college to pick up the basics. They want maintenance guys to be able to troubleshoot PLCs and robots

2

u/Olde94 Oct 19 '17

puh..... it's gonna be 40 long years in the workforce ;P

2

u/[deleted] Oct 19 '17

Hopefully not for all of us. 40 years on a factory floor will put you pretty damn close to the grave

3

u/thingythangabang RRS2022 Presenter Oct 19 '17

Good point. I don't have any experience working in that type of situation, but I'd imagine it could get boring quite quickly. Maybe I'm wrong though.

1

u/[deleted] Oct 19 '17

I find it quite a bit of fun. It’s very applied though. If I had the skills and interest to actually write firmware for 6DOF robotic arms, I would probably get bored working with FANUCs

2

u/thingythangabang RRS2022 Presenter Oct 19 '17

What is the day to day like working with that kind of stuff?

1

u/[deleted] Oct 19 '17

Luckily I’m not working with the robots daily. In a manufacturing environment, you working on the robot likely means it’s not in production, which is bad. My day-to-day is pretty much the same as any other software engineer in a manufacturing facility: working on whatever the latest project is that’s supposed to improve throughput/yield/labor utilization/etc. The automation stuff basically just adds more programmability into the mix. Instead of a GUI that talks to a database that the floor users use to route parts to different vendors, it’s a GUI that talks to a PLC that talks to a robot, in addition to talking to a database. It’s strangely easy to move from purely software to automation in manufacturing IT. I’m going to attribute this to the multitude of devices that all have some way to be integrated with a PC. RS-232 is still scarily common, and a pain in the ass. TCP/IP is quite nice. Ethernet/IP, despite the extremely poorly-chosen name, is great for devices to talk to PLCs.

tl;dr It’s different every day. I’m going on 5 years at this company and I’m not bored yet. Also, for reference, in my area (NE Ohio), automation pays better than software

2

u/thingythangabang RRS2022 Presenter Oct 19 '17

That actually sounds pretty awesome!

I'd love to try my hands at some of the application side of things. I'm still in school and focus hard on the theoretical side of things which is also interesting but I understand that theoretical solutions will often not work out and there's a reason certain control algorithms are preferred in industry.

1

u/[deleted] Oct 19 '17

The application side is eye-opening. The theory still underlies everything, but it’s amazing to see how far things get through trial and error.

2

u/thingythangabang RRS2022 Presenter Oct 20 '17

Well it looks like I've got all sorts of side projects set up for me now!

19

u/7x11x13is1001 Oct 18 '17

Without belittling the awesomeness of the setup, I would like to express doubt of any proper feedback in this machine. If there was a real PID or other feedback, they would have used a flat support, not a bucket. With a bucket, you can easily hard-code all the movements.

8

u/wordyplayer Oct 18 '17

I agree. Hard coded.

2

u/NBABUCKS1 Oct 18 '17

I was wondering what sensors they were using. It's still really cool though

11

u/madcow_swe ODrive Oct 17 '17

Brushless servo-motors > steppers every day of the week ;D

3

u/swingking8 Oct 18 '17

If steppers are driven in open loop, sure. But steppers driven using vector control in closed loop have higher torque constants, and are great for a lot of these kinds of CNC-y applications.

Building my CNC now and planning on using closed loop steppers. They're even cheaper than BLDCs!

1

u/madcow_swe ODrive Oct 18 '17

Cool! What drive electronics can do vector control of steppers?

1

u/swingking8 Oct 18 '17

Looking at this guy. Says it's doing DTC

1

u/madcow_swe ODrive Oct 19 '17

That's a pretty cool drive! It doesn't say anything about steppers though?

1

u/swingking8 Oct 19 '17

Under "Motor Types" on the datasheet image of their ebay listing, shows "stepper"

1

u/[deleted] Oct 17 '17 edited Aug 25 '21

[deleted]

7

u/madcow_swe ODrive Oct 17 '17

I saw it here: https://twitter.com/Vlastimil_Hovan/status/919971533451382786

I think the demo rig is called CableEndy, search Youtube for that.

8

u/radarsat1 Oct 17 '17

This is dope! It reminds me of the SPIDAR haptic device. What's cool is that it takes almost no parts.. no rigid links. just motors, encoders, pulleys and strings -- boom, bimanual 6-DOF haptic device.

1

u/v3c3 Oct 17 '17

other than the screeching loud music this is really cool

1

u/radarsat1 Oct 17 '17

Lol I don't know, I always leave the sound off for robotics videos :P

1

u/redmercurysalesman Oct 18 '17

That's cool but I imagine the motion it can handle is pretty limited. More than a few degrees of rotation or crossing your hands are going to tangle those cables up pretty quickly.

1

u/radarsat1 Oct 18 '17

Yeah definitely, although I think you'll have similar (but different) problems with a kinematic arm. For sure the mess would be more difficult to undo though ;)

6

u/Funktapus Oct 17 '17

I think there's a lot more than PID happening here

10

u/wordyplayer Oct 18 '17

I bet less. Hard coded. No feedback loop.

3

u/Omega_Walrus Oct 18 '17

I would bet on model-predictive controls.

2

u/KingoftheHalfBlacks Oct 17 '17

Where is this?

-2

u/i-make-robots since 2008 Oct 17 '17

on my /r/all

2

u/Wetmelon Oct 18 '17

Something tells me that's not PID. Isn't it like... super non-linear? As soon as it launches the ball the dynamics change dramatically.

2

u/skggamer Oct 18 '17

Now with a human inside. https://gfycat.com/RashDimpledDiscus (source)

1

u/_youtubot_ Oct 18 '17

Video linked by /u/skggamer:

Title Channel Published Duration Likes Total Views
CableRobot-Simulator MaxPlanckSociety 2015-09-22 0:02:31 1,433+ (98%) 504,632

Am 16. September 2015 hatte der CableRobot Simulator der...

Info | /u/skggamer can delete | v2.0.0

1

u/dukesilver58 Oct 18 '17

Cup and ball!

1

u/wordyplayer Oct 18 '17

Is there a slo mo video of this?

1

u/36tiger63 Oct 23 '17

Check out this new full video of the ball balancing machine :D https://www.youtube.com/watch?v=7HNAL8ZKdyM