How much Fillament do you need?

It took me about 3 spools of 1kg to print all the pieces.

Good morning. I'm not very good at robotics but I want to make thor.
For the assembly of the pieces is "easy" with the video but the electrical assembly ... is there any step-by-step guide for the electrical assembly?
thank you very much!!

Hi! There is a video made by a spanish maker if it helps you! https://www.youtube.com/watch?v=h2etAO7VM4c

Sorry for the late reply! I don't know why but the notifications were off :(

Hi,  in this website we can't found the new piece  that is located at the base, that supports the new model endstop  of the robot, in order  to print it. Could you help us ?

Hi there, 

I'm a student, now i'm studying technology in my institute called IES Ciudad Jardin in Seville.

I and a friend are working on this proyect and we have some doubts. At the  pieces Art56CoverRing, Art56GearPlate,  we found  some slacks and we don't know if in the original pieces there is a slack or not.  ( Art56GearPlate makes a vertical and lateral movement ).Could you help us ? 

Do you have solid models that were not created from a mesh?

I designed it using FreeCAD and the source files are published in the github's repo!

The STEP and STL files are published too.

Sorry for the late reply! I don't know why but the notifications were off :(

Hi there,

I was not able to find any technical details with regards the payload, reachability and precision. Have you done any tests on the robot and if so, could you share the values? I appreciate your answer.

Hi Felipe, first of all sorry for the late reply! I don't know why but the notifications were off :(

To be honest I never tested the precision accurately. The maximum payload that I succeed to move was 750g in its worst position. Hope it helps!

Any word of advice regarding the use of 3D print material since Angel used PLA to print all parts. i want his build to be durable and and heat resistant.

Hi Donskit, first of all sorry for the late reply! I don't know why but the notifications were off :(

I printed it in PLA just because it was easier for me. If you have the chance to print it well using ABS or other filament with better heat and mechanical resistance do it!

Hi AngelLM,

I just want to let you know that I'am also building the Thor robot arm with the Add-ons from Dannyvandenheuvel.

Below the link to my buildlog. 

https://hackaday.io/project/26341-building-the-thor-robot-arm

I want to thank you for all your hard work. I really like the result. 

Sepio

Yay! Welcome to the Thor family! :)

I just added you to the Thor's Builders list (https://github.com/AngelLM/Thor/wiki/List-of-Thor-Builders), do not hesitate to update your status when it's assembled!

Also, feel free to post your questions, feedback and progress in the Thor's community (https://groups.google.com/forum/#!forum/thor-opensource-3d-printable-robotic-arm)

Willing to see more!

Ángel L.M.

hi Someone is able to make me understand exactly how to mount the 2 nema in the upper extremity of thor? It is not very clear. Thank you

Hi Mogol, sorry for the late reply!

Each motor in the upper articulation have 2 printed pieces that have to be attached to each side of the motor. After that, each motor can be slided inside the Art4Body piece, using the inside guides (Dovetail shaped) that should fit with the pieces attached to the motors previously.

Hope it helps!

I just downloaded the files and it does not appear that the provided STLs can be printed using a makerbot replicator/Flashforge Creator/ QIDI Tech I. Has anyone already modified the model to be printed using a 225 x 150 x 150mm (8.8 x 5.9 x 5.9 inch) print area?

Hi Michael,

I designed Thor to be printed in a 200x300mm bed printing area, but there are users that splitted some 3D models to make them fit into their printers.

I suggest you to visit the Danny Hackaday Page (https://hackaday.io/project/16483-building-the-thor-robot), as he was the first to split some pieces in half. 

You can also open a new thread in Thor Community (https://groups.google.com/forum/#!forum/thor-opensource-3d-printable-robotic-arm), I'm sure that we'll find a solution ;)

Hope it helps!

Thanks for your prompt reply. I look forward to building a Thor.

Just stumbled across Thor while looking for a new project. This looks really cool! I am curious though about the motion. Does Thor have Linear motion capabilities or does he move strictly joint by joint?

Hi reillyer,

My Thor robot is moving using Fordward Kinematics (joint by joint) just because my electronics don't have the power enough to solve the Inverse Kinematic equations in real time. I'll try soon to solve that equations in my PC (as I'm controlling it with one) and send the solved position to the electronics. In this way I'll get a Linear motion ;)

We have a discussion at Thor's Community about this topic, feel free to visit us :) https://groups.google.com/forum/?utm_medium=email&utm_source=footer#!topic/thor-opensource-3d-printable-robotic-arm/GYjeoyt_SRU

I have started printing parts for this. As i do so, I am wondering if anyone has thought about scaling up the design to accommodate NEMA 23 and 34 motors?

Hi Adam!

I remember that someone asked me about scaling it to fit larger motors, but I don't really know if that person started doing it or not :/

Anyway it would be a nice project!

Maybe Danny has better results in the 3D printing quality but in my prints I have noticed that for accurate movement your "theoretical" calculated movement will not be accurate enough for reliable automated percision movement. Joystick control yes, but repeating the process I doubt it. 

Also every 3D model that gets printed will be slightly different.

I think in the software must take into account imperfection to compensate. But first I think we need a mechanism to actually measure the imperfections first.

Hi Olaf! What is the calculated movement that are you talking about? About repeatability I didn't test it yet, but I got almost equal movements doing a process two or more times. I'll upload a video soon :)

Printing tolerances is an issue hard to deal with... Every printer has his own tolerances and are different from other printer, as there are only one 3D model to print probably there will be some printed pieces better than others.

Of course doing a closed-loop control with sensors (potentiometers or encoders) will ensure that repeatability.
If it helps you I applied the trial and error method to identify my printer's tolerances before print them. 

Best regards!

It is only intended as feedback so we can improve the Thor ;-)

I am not that far yet, I am now building the code (proof of concept). I have now my base that can actually rotate. But when you look at the side, then you see that the plastic top is a bit tilted. This will affect the precision when I ask the robot to rotate around its axis. The payload may shift up or down depending on the angle.

I have been toying with the idea of a Gyroscope+accelerometer, but I am still busy setting it all up (buying the electronics, wires, .... since I am a complete N00b)

Another thing I am thinking of is to use a photo-detector with a ring hat has multiple varying spaces. If one space is 5 steps to cross and another 10 steps, yet another 15 steps  then it has a sense of direction but also a sense of how off its position is. It could compensate real time during the movement.

Example: If the software expect a gap that starts at position 105 but it already detects it at 103 then the robot knows that it must add 2 additional steps to get to the correct position. If that gap is in the middle of normal operation then the robot can work longer with less need of a recalibration getting to the home position.

The hardest part is to develop that software and squeeze it into that small memory space :-)

Ah yes: "Calculated movement" Your forward kinetics formulas.

Of course! I really appreciate your feedback :) I think it's the only way to progress! 

About the forward kinematics and control: to be honest I estimated the steps per unit (the steps that the motor has to rotate to complete a degree in this case) in firmware by trial and error, maybe it is the main issue about the forward kinematics control. I'll upload soon the steps I followed to do it. About repeatability, do you have some backlash between pinions and gears?

Best regards!

If I can find time this weekend I will test accuracy. I did try to hold the base with my hand to see if it broke or halted the stepper motor, but it has decent force. But I did manage to make it stop by hand. (The plastic itself did not bulge)

I also discovered the mystery why my optical ring came lose. It turned out that the screw that held the stepper motor cog in place was a bit too long. When I assembled it I did notice but it probably pushed the optical ring from the inner cog base.

I am wondering when you move a heavy object how it behaves too. We may have to modify the stepper motor code to accelerate slowly and also stop more slowly to keep accuracy. I am wondering if we can put a weigh senors in the base so that the robot motor controls can optimize its speed depending on teh laod it carries.

The main reason I did not build the robot so far, I tried to make the software almost complete and experiment with it to see what are the main bottlenecks and issues to have a perfect robot. After all proofs are well done I build it for 100%. I printed all parts and I see some problems with the heating and the precision. For the heating I gonne modify some parts with build-in fans like AngelLM already done, for the precision I am thinking to make a feedback with a encoder or something I can measure to angle. In that way I can make a closed loop controller for the stepper motors. If I make it absolute I don't have to home, just for the first time setup. I have to luck to have a proffesional stratasys uprint se printer, the accuracy is a lot better than the hobby printers. I didn't have any problems printing the parts, some parts I made a little smaller or broken into two parts because the dimensions of my printer area. Olaf, if you wish, I could make that part where you have some troubles with be split in two parts, I will mean, the upper shrew blocks could be the second part with a little inlay plate to fit inside the second plate and can be glowed togetter. Then you can print both parts without structures.

You are reading my mind, I too am focusing on seeing how the robot behaves first so I can pair the software and the mechanics so that act as one entity. If only I had more time after my day job :-) 

I am interested if you could modify the model to avoid having support material to be the Guinea pig :-). I probably wasted 25% or more plastic on that support structure. The plastic is not the issue but the time to print it is more of an issue.

I think what is important for people that wants to copy the Thor is that it can be printed in 12 hour maximum 3D prints. The longer the print lasts the bigger a cache that a print fails. In addition, people are less interested because the part is too big so people give up to soon.

I really do enjoy both of your work greatly. It challenges me and it is very rewarding when parts comes together and start to acvtually move.

Hi there, I'm looking to build a Thor, and am ordering parts now. I would like to modify the model to fit a hitec servo, as I'm reusing the servos in another project. Do you think it is possible to do so without altering the mechanism too much?

Can I ask where you are ordering your other parts from? I am also trying to put this build together and quite frankly I have no idea where to begin! 

On a more general note, I downloaded the ListofMaterials.txt file but it looks like steppersonline.com is no longer a working domain and also the counts for the quantity of each motor is off (for example, the .txt file says you'll need (2) 40mm Nema 17 servos but the components list on this page says you only need 1. I've also checked the hub and it calls for only 6 servos (versus the seven in the txt file and the components section of this page) and of those 6, half of them are Nema 17 and the other half are Nema 14. What is the difference? Are the 14s just smaller/lighter? Does it matter which ones you get, or will it affect the performance/strength of the arm?

Any help is appreciated, 

Justin 

I'm getting most of my parts off taobao.com. Nema is a size standard; Nema 17 means 1.7 square inch face plate. Nema 14 is 14 square inch face plate. Download FreeCad and the fcstd file and look for yourself.

Motor size doesn't necessarily correlate with performance.

You're a life-saver Vader! Thanks so much!

Sidenote: How many of each motor do I need? The hub says I need 6 total, and this hackaday page says I need 7 total... Does it matter?

7 based on the model.

I also have a hard time to find the components, they are spread everywhere.

I ordered the motors from this site: http://eu.stepperonline.com/ but so far I have not been at a point to actually test the motors. It took some time to receive them. Also be careful, some people seem to have had a import tax, I did not.

There are 6 degrees of freedom so in theory 6, but one of the joints needs 2 motors that work together to get the needed power to get the arm up.

There are 3 motors that have a planetary 5:1 gear ratio, those are pretty expensive (I got them for €31 each).

Also the big ball-bearing for the base is hard to get. I found one on Amazon for €31 but I never received it and Amazon canceled the order because of undeliverable. I got refunded. 

You can find a lot of things at reprapworld.com. For the motors, I used three types,
for the base I use a little more powerfull type 17HS16-2004S1 and for the first arm and second arm movement I use 3 geared motors 17HS13-0404S-PG5 and for the wrist and tool rotate and up/down movement I used 3 motors 17HS13-0404S. All motors I ordered at steppersonline. Please consider to take they last 3D parts because they will be corrected with extra fans to cooldown the chambers.
The next comming days I will do a full reupload off all my modifications. I will make a new list of materials where you can find all parts at the moment. I changed some 3D parts so you can use more standard products that you will find on the internet.

Greetings,

Danny

Hi all! on my page the first glimps of the graphical controller!
Basics has been fullfilled! Now the big works arrives making the
simulator and after that the real TCP socket connection between this
piece of software and the real robo arm!!!!
Take a look and give any comments as you like, all feedback is welcome!

As I posted on the YouTube video, it blowed my mind. Awesome work. You lifting this project to a new level!
Best regards!

(I'll download it right now to see it in actiooooon :D)

BTW, it will be a version for PC and MAC! 

Hi all! Update!

I've been working hard on the graphical GUI controller at the moment and must say it's moving fast! Inverse kinimatics is working great! There will be Joint jogging and Cartesian Jog with translation along or rotation about X,Y and Z axis. Camera views has a lot of improvements. Watch out these comming days for the first real release! :)

Hello, am I wrong that Art4Optodisk.stl is missing in your files list?

I am builkding your robot :-)

Hi Olaf! You were completely right, I just uploaded the stl file of Art4Optodisk to the Files List, I'll update the github repository later.
Thank you for the appreciation :)

Hello Thor team. I am proud to be building one of these awesome robot arms. my goal is to control it through rhino and grasshopper so that driving the movements can be para metrically controlled. First got to build Thor though. Its taken me a while but I am up to the largest parts now . Thanks to danny vdh for breaking some parts up into smaller pieces. Ill look for those now. I have an ultimaker 2 and some parts are just too big. In the future i hope to also find someway to laser cut some of the parts... so that the fabrication can be faster. and maybe to have an acrylic window to see into the inner workings! I look forward to seeing the builds of others. :) ethan

I made some modifications on thor to print it on smaller area 3D printers, I will put the step and stl files later this day on my github page! You can find me on the github page of Angel. There will be a link to my github! If you have any questions don't hesitate to give me some feedback! Success in making a real Thor! (Needed me two weeks to print the whole robot!)