New polar concept/design Hello, Well first of all, I'm from Argentina and my english isn't the best I come to the design at my obsession to get my first printer that because of problems with importation in mi country its really difficult to get one. I had centered on the price (quantity of parts and availability), relation between printing zone and printer volumen, possibility of adding a 3d scanner and avoiding classic thread rods and belts. It has delta based module-z axis and polar radius. I gave dimensions to fit a printing cylinder of diameter of 280 and 200 height. with heatbed also I want to hear all possible improvements and problems that it could have, based in your experience, i remind you that I have never had a printer :D That is just a concept drawing: [img]http://i.imgur.com/caR9NEE.png[/img] https://reprap.org/forum/read.php?185,281278,281278#msg-281278 Thu, 05 Mar 2026 06:08:23 -0500 Phorum 5.2.23 https://reprap.org/forum/read.php?185,281278,288188#msg-288188 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,288188#msg-288188
Quote
nicholas.seward
Not directly related but fun nonetheless.

[youtu.be]

great designs, but delta's relation between print height and printer height is really big

I was seeing new posibilities because of precision problems and found this
youTube
that reminded me the reprap lewis

I'm going to try something similar with posibility of 3D scanner
]]> Gomez.Marcos Polar Machines, SCARA, Robot Arms Thu, 02 Jan 2014 18:58:14 -0500 https://reprap.org/forum/read.php?185,281278,288148#msg-288148 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,288148#msg-288148
[youtu.be]]]> nicholas.seward Polar Machines, SCARA, Robot Arms Thu, 02 Jan 2014 17:41:08 -0500 https://reprap.org/forum/read.php?185,281278,287758#msg-287758 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,287758#msg-287758 Does this clear it up. You can see that no matter what position the arms are in that the length of string from the tie off to the bottom of the effector pulley is constant.]]> nicholas.seward Polar Machines, SCARA, Robot Arms Thu, 02 Jan 2014 01:53:14 -0500 https://reprap.org/forum/read.php?185,281278,287733#msg-287733 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,287733#msg-287733 ok, for example we have the effector centered in x axis, with any z movement it would need length changes
maybe the shoulder pulleys must have same diameter than effector to correct length?
and the low arm pulleys?]]> Gomez.Marcos Polar Machines, SCARA, Robot Arms Wed, 01 Jan 2014 20:58:50 -0500 https://reprap.org/forum/read.php?185,281278,287691#msg-287691 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,287691#msg-287691 nicholas.seward Polar Machines, SCARA, Robot Arms Wed, 01 Jan 2014 19:02:43 -0500 https://reprap.org/forum/read.php?185,281278,287684#msg-287684 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,287684#msg-287684 Gomez.Marcos Polar Machines, SCARA, Robot Arms Wed, 01 Jan 2014 18:46:25 -0500 https://reprap.org/forum/read.php?185,281278,287327#msg-287327 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,287327#msg-287327 nicholas.seward Polar Machines, SCARA, Robot Arms Tue, 31 Dec 2013 20:46:43 -0500 https://reprap.org/forum/read.php?185,281278,285168#msg-285168 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,285168#msg-285168 the one sided have no big precision differences, and have bigger print volume

about compound pulley is not bad idea... it would be on an adjustable bolt that tense it

EDIT:
recalculating... one sided have lots of precision losses, you have reason one more time]]> Gomez.Marcos Polar Machines, SCARA, Robot Arms Fri, 27 Dec 2013 02:17:02 -0500 https://reprap.org/forum/read.php?185,281278,285159#msg-285159 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,285159#msg-285159
I think if I was doing this basic design that I would probably use a compound pulley design. I think two 1:5 ratios for a grand total of a 1:25 mechanical advantage would be about what I would go for.
EDIT: I would go with the worm drive if you want to drive from the shoulders. All the tricks to get string to work here would be a turn off to most.

However, I would personally go with the two sided approach and drive the elbows. (This is mainly because of all the tricks I see that would have to be done to get the one sided approach workable would take away from the elegance in my opinion. This is also because it is 4DOF ready and there elbow pulleys can be huge and not hurt anything.)]]> nicholas.seward Polar Machines, SCARA, Robot Arms Fri, 27 Dec 2013 01:24:40 -0500 https://reprap.org/forum/read.php?185,281278,285154#msg-285154 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,285154#msg-285154 I have managed to get everything right there in a compact zone

EDIT: your crazy ideas are really difficult to see for me]]> Gomez.Marcos Polar Machines, SCARA, Robot Arms Fri, 27 Dec 2013 01:08:56 -0500 https://reprap.org/forum/read.php?185,281278,285142#msg-285142 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,285142#msg-285142
Note: string is cheap but a belt will require less calibration. (For the record, I would probably go with string.)

Super crazy idea: you could counterbalance each arms so that the arms would be in equilibrium everywhere. This will add inertia to the system but will allow your pulleys to be smaller than they had to be without the counterbalancing. With the counterbalances you only need the mechanical advantage to get the resolution you need. You won't have to use the MA for raw movement.]]> nicholas.seward Polar Machines, SCARA, Robot Arms Thu, 26 Dec 2013 23:53:23 -0500 https://reprap.org/forum/read.php?185,281278,285138#msg-285138 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,285138#msg-285138
what do you think?]]> Gomez.Marcos Polar Machines, SCARA, Robot Arms Thu, 26 Dec 2013 23:42:54 -0500 https://reprap.org/forum/read.php?185,281278,285096#msg-285096 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,285096#msg-285096
I don't necessarily recommend this link but your design will live and die by the quality of your worm gears so I would buy some professionally milled ones. If you have a better source I am very curious. Good luck.

I will see if I can do some calculations but I would go for at least 20 or 30 teeth on your worm gear.]]> nicholas.seward Polar Machines, SCARA, Robot Arms Thu, 26 Dec 2013 19:51:34 -0500 https://reprap.org/forum/read.php?185,281278,285092#msg-285092 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,285092#msg-285092
thanks, I was wondering how to avoid backslash, but seeing in that way it wouldn't have to have, except for the green arm that sometimes have angles >90°]]> Gomez.Marcos Polar Machines, SCARA, Robot Arms Thu, 26 Dec 2013 19:42:05 -0500 https://reprap.org/forum/read.php?185,281278,285081#msg-285081 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,285081#msg-285081 nicholas.seward Polar Machines, SCARA, Robot Arms Thu, 26 Dec 2013 19:05:21 -0500 https://reprap.org/forum/read.php?185,281278,285019#msg-285019 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,285019#msg-285019
coming back to design, I'm going to use worm drives, as suggested by nicholas, to get the needed mechanical advantage]]> Gomez.Marcos Polar Machines, SCARA, Robot Arms Thu, 26 Dec 2013 16:41:53 -0500 https://reprap.org/forum/read.php?185,281278,284068#msg-284068 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,284068#msg-284068 now with colors to understand the mess


]]> Gomez.Marcos Polar Machines, SCARA, Robot Arms Mon, 23 Dec 2013 22:06:54 -0500 https://reprap.org/forum/read.php?185,281278,284002#msg-284002 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,284002#msg-284002 and the wrist pulley can rotate independently of the forearm,
then I can see the end effector remaining parallel to the horizon with the figure 8 belt.

You need to invest in a set of Legos :)]]> A2 Polar Machines, SCARA, Robot Arms Mon, 23 Dec 2013 19:25:51 -0500 https://reprap.org/forum/read.php?185,281278,283908#msg-283908 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,283908#msg-283908
Quote
A2
Looks like that will work (tu)
first one? Idont know because there isn't relative rotation but maybe the second works... I HATE PULLEYS REALLY CONFUSE ME]]> Gomez.Marcos Polar Machines, SCARA, Robot Arms Mon, 23 Dec 2013 15:09:42 -0500 https://reprap.org/forum/read.php?185,281278,283906#msg-283906 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,283906#msg-283906 A2 Polar Machines, SCARA, Robot Arms Mon, 23 Dec 2013 15:03:56 -0500 https://reprap.org/forum/read.php?185,281278,283864#msg-283864 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,283864#msg-283864
SOLVED?:

OR

I'm not thinking clear, I'm going to give a rest
]]> Gomez.Marcos Polar Machines, SCARA, Robot Arms Mon, 23 Dec 2013 13:47:18 -0500 https://reprap.org/forum/read.php?185,281278,283762#msg-283762 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,283762#msg-283762 ekaggrat Polar Machines, SCARA, Robot Arms Mon, 23 Dec 2013 09:53:59 -0500 https://reprap.org/forum/read.php?185,281278,283568#msg-283568 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,283568#msg-283568
I like it, but ekaggrat´s arm looks great and with less parts
I'm going to implement it on the printer

EDIT:


is going to need a motor for effector's level correction :/
]]> Gomez.Marcos Polar Machines, SCARA, Robot Arms Mon, 23 Dec 2013 00:21:53 -0500 https://reprap.org/forum/read.php?185,281278,282961#msg-282961 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,282961#msg-282961 but I'm still going to finish printer and then the surgebot or any else]]> Gomez.Marcos Polar Machines, SCARA, Robot Arms Sat, 21 Dec 2013 10:23:19 -0500 https://reprap.org/forum/read.php?185,281278,282881#msg-282881 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,282881#msg-282881 I see why you are confused, I didn't construct a complete assembly using 2 arms.
Here is a picture with two arms.

The idea is you mount a scanner on the end effector,
rotate the table, and swing the arms down parallel to the table.

This allows you to scan 360 degree, and you can scan the top of your object,
which no other 3d printer/scanner combination can do, that I'm aware of.

And we can use this configuration to do minor surgery!!!! (:D

Lets say I have a minor tumor on my cheek, and I'm in a 3rd world country with no surgeon to help me.
1. Place markers on my face, it can be a piece of tape.
This is so the computer an find an orientation.
2. You scan my face.
3. You then program a sequence for the robot to exercise the tumor.
Or a surgeon from another country performs the surgery remotely, and/or with preprogrammed automated sequences.
4. You would have a quick change tool holder/turret with medical devices.
5. When the surgery is done the patient gets a smiley face sticker to take home :)




]]> A2 Polar Machines, SCARA, Robot Arms Sat, 21 Dec 2013 06:23:49 -0500 https://reprap.org/forum/read.php?185,281278,282834#msg-282834 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,282834#msg-282834 it would reach 8-10 microns with just 5 MA
EDIT:
I made graphics...I would need 10MA for a 35 to 10 microns

]]> Gomez.Marcos Polar Machines, SCARA, Robot Arms Sat, 21 Dec 2013 01:29:37 -0500 https://reprap.org/forum/read.php?185,281278,282830#msg-282830 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,282830#msg-282830
Quote
Gomez.Marcos
...
it was difficult to understand the movement, i think that is only needed pulley friction in the effector, right?
...
how much print volume give your GUS arms??
...

Yep, only the effector needs friction.

GUS arms can do whatever you want. The ones I use can actuate a distance from about 25mm to 325mm. You can design them however you want.

I didn't check your math but I would suggest 25 microns as a good target. That agrees with my earlier statement that you need a mechanical advantage of 5-10.]]> nicholas.seward Polar Machines, SCARA, Robot Arms Sat, 21 Dec 2013 00:58:07 -0500 https://reprap.org/forum/read.php?185,281278,282801#msg-282801 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,282801#msg-282801
Arms = up/dn + in/out. = 2.
Gimbal swing side to side = 1.
Table revolute pivot = 1.

I can see that the way I have it drawn that one might think that the shoulder pivot also moves in, and out, which would add another DOF.
But I don't think that is needed, but it would be fun to watch it if you did add it (I bet it'll burn some brain cells if you did add it) :).

You could also add a pan/tilt to the table.
You could spin the extruder.]]> A2 Polar Machines, SCARA, Robot Arms Fri, 20 Dec 2013 21:51:21 -0500 https://reprap.org/forum/read.php?185,281278,282800#msg-282800 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,282800#msg-282800 Gomez.Marcos Polar Machines, SCARA, Robot Arms Fri, 20 Dec 2013 21:41:30 -0500 https://reprap.org/forum/read.php?185,281278,282796#msg-282796 Re: New polar concept/design https://reprap.org/forum/read.php?185,281278,282796#msg-282796 How about you put it on a gimbal, we're get closer to SurgeeBot :D
Table can be linear, and/or revolute pivot, (i.e combination of both).




]]> A2 Polar Machines, SCARA, Robot Arms Fri, 20 Dec 2013 21:03:00 -0500