08/17/2017 at 09:31 •
It’s been a long time since the last time I wrote a log! I’m back!
Thor’s community is growing fast! There are (at least) 4 Thors assembled & operational around the world and another 17 being built! There are schools and universities relying on Thor for teach robotics… Great yaaay!
The more people are interested in this project, the more feedback I get. Recently I have received several questions about the sensors I’m using to establish the home position of Thor (opto-couplers, opto-transistors, opto-switches… whatever). To be honest, until now it was pretty tricky… I made my own sensors using a DIY CNC for the PCBs and soldering the components by myself. As this project has attracted different kinds of people, I thought that it could be nice to simplify this issue: making Thor compatible with commercial sensors instead of creating the custom ones. Let’s try to not reinventing the wheel!
The first thing was to find a cheap commercial sensor which could fit inside Thor. To make things easier, I was looking for a single model which could fit in the 4 articulations. For the first three ones was an easy task, but the sensor located in the Art3body piece for the 4th Articulation had to be pretty small to not collide with the Art4TransmissionColumn piece.
Finally I found this one in Aliexpress which met all my needs. I think that it won’t be hard to find that kind of sensors in other online-shops, but I tend to use Aliexpress because of its large catalogue.
So, without further ado, these are the changes I made in the design (on the left side the old design and on the right side the new design):
The sensor for the 1st Articulation is now fixed to the BaseBot piece.
The sensor for the 2nd and 3rd Articulations are placed in a similar position as the custom ones, I modified the Art2BodyB piece adding fixing point for them. Also, the Art23Optodisk has been redesigned to work properly with the new distances.
The Art3Body piece has been redesigned to fix the sensor of the 4th Articulation. The board of this sensor has to be cut to avoid the collision with the Art4TransmissionColumn piece. Do not worry about that cut, there are no circuits in that zone of the PCB, so can be cut gently.
I have only tested it using the 3D models. The sensors fit, but presumably the connector of each sensor will have to be replaced with other flatter.
FYI: the last commit where you can find the older files (the ones for the custom sensors) is this one: b86594c4d48fa64d71cc373a52b4e3dac6e4bde9
Do you like it?
08/08/2017 at 19:28 •
It's the crossover episode you've been dreaming about!
THOR robot arm is now simulated in Robot Overlord. Forward and Inverse kinematics can be manipulated visually in 3D. I feel confident it won't be long before RO is talking to the firmware and any THOR owner can drive their arm from the software. One step closer to fully open source process automation!
Special thanks to @angelILM for producing the STL files and dimensions on request.
04/22/2017 at 14:13 •
I just made a Wiring Diagram for the Control PCB v1.0 board.
You will find the full resolution image & source files at the Github repo.
I want to remind that there is a Google Groups community with 90 members in this right moment where you can ask, share and read about this project! Join us! :)
Check soon my fork of the grbl repo to get the lastest firmware for the ControlPCB board.
01/15/2017 at 16:30 •
Since a few weeks I'm receiving a lot of questions/feedback/information from many different directions (email, Twitter, Hackaday, Thingiverse, GitHub, Wevolver, etc.).
One thing is clear, this project has become known, at least more known than I expected at the beginning, and I cannot do other than thank you! Thank you for your likes, your comments, your feedback, for sharing the project, contributing to it and for building a Thor. You rock!
Also, from the very beginning I wanted everyone to became part of this project and share all the information. I think that the current platforms I'm using are not the ideal ones to develop a community project. Using a lot of platforms is convenient for spreading the word, but not for focus the information...
That's why I decided to make the Thor mail-list community. I have been in other communities of Google Groups and it works so well. Everyone can access, everyone can ask/answer/show, it's easy and clear and it's free. In this way I want to share all the info I have with you all. And you will be able to help, give/get feedback and share your ideas, progress and modifications with other community members.
From now I'll group all info there and I'll be answering the questions there. I'll be posting there my progress and changes too (I will still doing that here too).
See you there!
EDIT: I forgot to say that I also did a Frequently Asked Questions in order to answer them :)
12/19/2016 at 16:05 •
Time ago, Danny made some modifications to largest pieces, splitting them and making them printable in 180*180mm bed area printers.
He made an awesome work, and I wanted that modifications to be in the main repo, so I added it! Also, I migrated the design to FreeCAD in order to have the source files too ;)
EDIT 21/12/16: I have migrated another 2 modifications to FreeCAD :)
On the left, my remix of Art4Body modification made by Danny. Designed for low height printers, thank you again Danny :)
On the right, the BaseBot modification made by Ctrl-Alt-Dude for 190*190mm print area. This will allow more users to print Thor. Thank you too! ;)
Are you having issues with other pieces?
Season's greetings for all!
12/16/2016 at 14:33 •
Yay! I received them 3 days ago... Exciting!
I ordered them to PCBWay and my experience was great! They are fast, kind and very cheap :D And the quality of the PCBs is incredible, very professional. I'll work with them again for sure!
As you see I have designed it for THT and SMD (1206 package) components. I never used SMD before, but there's a first time for everything haha.
Now, it's time to wait for the arrival of the components... I think that it will take about a month or two... I don't know if I'll be that patient...
Hope you like it! :)
12/07/2016 at 21:43 •
Woah, more than 300 followers! Hello everyone!
As I said weeks ago, I needed a new electronic board to control Thor... The one I was using had many mistakes (a man may learn wit every day...) and I got tired of botching it. The initial idea was design a DIY PCB board, but due to its limitations and how cheap is to manufacture it in China I decided to design a better control board.
Of course using OpenSource software, KiCad again.
First of all, some pictures:
It took me a few hours to understand the values that I had to set (track width, drills diameters, etc.) in order to send it to the manufacturer... but it won't happen the next time >:D
Anyway, the new features:
- First and the most necessary: Reverse current protection circuit. No more burned drivers because of mistaken power input polarity... It will save my wallet!
- This board allows to control up to 8 stepper drivers (instead of 7 of the previous version).
- Smaller size: Less than 100mm*70mm.
- Easier assembly: the Silkscreen is a nice helper!
- Added 3 confirmation LEDs (Power Input, PCB Power, Arduino Power).
- Added more 12V aux outputs for the fans.
- Added a switch to power off the steppers and keep the fans working.
- The connections between the drivers and the male pins that connect with the Arduino Mega are now well driven. This has been possible thanks to the 2 layers board, and it will allows to simply connect a ribbon cable with a 2x18 connector without "hacking it"
And I think that's all! I'll send it to the manufacturer as soon as I finish another PCB I'm designing.
Of course, I shared it on the Thor's Github repository. If you are reading this close to the publish date, you will find the new PCB files in the ControlPCBUpdate branch. Feel free to take a look and share your opinions!
Hope you like it!
11/21/2016 at 16:11 •
This weekend I was at Bilbao Maker Faire showing Thor. The event was great and I met a lot of interesting people.
I met Antonio, the creator of DIMER, who was located next to me at the faire, so we managed to interact our robotic arms with each other... And here is the result! (Maybe the first marriage proposal between robotic arms?)
As you can see in the video, Thor is moving faster than weeks ago. I increased the speed of the slowest articulations about 50%. Soon i'll test the maximum speeds that Thor can support.
Another great new is that I have been using Thor for 8h non-stop working and it didn't broke or melt neither! Yay!
Next things I'll be working on: Test the maximum speeds, making a conveyor belt that will interact with Thor, design a new electronic board and add a new degree of freedom (hehe >:D).
Finally, I just saw the awesome work of Danny... Just go to his project page and see it with your own eyes...
11/07/2016 at 21:12 •
First of all, thank you for your 100 likes 276 followers & over of 15k views. You rock!
We have another thing to celebrate today hehe. The problem about melting gears and malfunction due to steppers overheating is solved :) Let me explain the steps I followed to fix it.
1. I measured the temperature of steppers in action... and it went over 70ºC. PLA starts deforming at 60ºC... So I had a real problem there. Not only the gears were deforming, also the Art1Body part were deforming and causing the malfunction.
2. I appreciated that my design didn't had refrigeration holes, so the heat produced by the steppers only could be dissipated through the plastic (bad idea because it was causing the deformation). After facepalming myself I redesigned the parts that contain steppers and introducing 40mm fans into the design. In this way, the motors would have forced cooling.
3. I tested it. And it worked well, now the steppers don't reach 40ºC and it goes well! Just in case I printed the gears using ABS to prevent the deformation. The test was performed at a 10h non-stop maker faire called OSHWDEM at A Coruña (Spain).
So, check the new design at GitHub repo before print it! And if you have printed it already don't worry. Take the dremel, do some holes and glue the fans! (I did this hahaha)
Aaaand... there you have a video of Thor doing a manipulation job. I think that the next step is increase its speed, don't you?
10/10/2016 at 12:12 •
I have received some applications from Hackaday users that wanted to be part of this project. And I think that it's important to explain how to be part of this project.
In one hand, this project is completely Open Source and shared on its GitHub's repository. This mean that you can share your modifications and beeing part of this project by doing pull requests, giving feedback or helping solving issues.
In the other hand, there is the "Project Team" on Hackaday. I don't really want (and I think no one wants) to have a Team with a lot of inactive users. I think that this Team is a nice place to share opinions, test designs, test features and things like that. Obviously, the team has the labour to gather all this information and make it public too!
In this way, everyone could access to all the info and the Team members would have a place to share their progress.
And the final question: How to be a Team Member? I think the best solution is accepting the requests of the users that contribute. So, if you want to join this Team, I suggest you to go to the GitHub repository, clone it, make something nice and send a pull request!
What do you think about this?