@benedekkristof16

Hello, guys!
3D printing has started, and I designed some important details for R2’s body: the Radar Eye, Shoulder and Battery box. Currently, I’m making the Leg Booster.
I still have to model the Ankle Cylinders and a few remaining details for R2’s dome.

Hello, guys!

Hopefully, it’ll be my last devlog about 3D modelling, and next time, I’ll build R2 in real life with my dear fellows, @benedekkristof16 and @hunorkiss04 .

I’ve spent hours and hours designing with varying degrees of success and from this mighty point, R2 probably has a much cooler look and far more aura than me🥀.

Unfortunatelly, this replica is NOT 100% accurate and I had to model some elements by sight (R2’s holoprojector) and I horribly miscalculated a ratio: R2’s main body (the cylinder) is 220mm and it should have been 200mm. I noticed it too late. Due to the complexity of R2’s torso and the lack of time, I didn’t correct this. It’s not that visible; however I had to let go of the two center foot cylinder due to a lack of space.

But it’s our R2, so We’ll keep him, no matter what 😉.

Hello, guys!

R2 has been built (mostly)!!!
With the help of my dear fellows (@benedekkristof16 and @hunorkiss04 ), we spent a lot of time working on it. As expected, we faced some difficulties during the building session.

The main problem was the CAD design and 3D printing: in some places the holes are too tight for the screws and there are defective pieces; however we could resolve all the problems with some unique solutions. At the end of the day, R2 is moving and he’s able to turn his head!

We’ve started to fill the GitHub files and I’ll fix the 3D mistakes. (Ignore the questionable paint job)

Hey! I think this will be my last, and my longest devlog! I need to clarify things, and address things, but first– I tell what I did. So I wired up the motor driver (an anquintance of mine helped to solder up the wires which will take the high current to the motors), wired up the LED’s, and put everything in the 3D printed chassis done, and assembled by @TamasLaszloffy777 , with the help of our friends (and my mom :) ). I soldered the wires to the motors, and glued the LED’s in the head. Now comes a list of things, that didn’t work: I copyed the HTML code my friend wrote into my code, but unfortunately I couldn’t get it working. I’ve spent countless hours debugging with Gemini, but as the project got more complex, it gave me more stupid answers. When I tested it with just the stepper motor, it worked, but with everything connected, it didnt. So out of desperation I’ve had to go back the old method I used at testing, which is that everything works with an USB cable. I’ve spent circa 30 minutes changing the code, and commenting out everything that has to do something with the wireless thing. Of course Hackatime didn’t register nothing out of this half an hour. This was the main thing why I used Lookout and Lapse for coding before the Ban. But after all, thank God it works now with USB (after some debugging with Gemini of course). This means that the LEDs also lost their purpose as wifi status indicators, so now the project has 2 spare LEDs inside. (I won’t put those in the wiring diagram, since they are not used, but its too much work to take them out. I saved two of them by repurposing them to “head turning indicators”, but left two out, because it would just make it harder for me to take the head off, to access everything inside. Also I plan to fix the wireless part in the future, but not in Stardance). The next thing I noticed, is the homing sequence is pretty useless. Fortunately the wires never twist dangerously, contrary to my previous assumptions, and R2 would have to rotate its head 360 degrees multiple times in a row for it to become dangerous for the wires. I was quite upset that I did the homing sequence, and bought the sensor for nothing, but keeping it would add unnecessary complexity. And unnecessary complexity is NEVER good in a project.(I wont put the sensor into the BOM list, nor into the wiring diagram)

So this time, I’ve had to update the entire code. So, as I’ve told you guys in my previous devlog, I’ve tried to make R2 wireless with UDP, but it did not work for some reason. Because of this, we decided to try another method. We will host a web server on the Pico! My friend, who knows this stuff, will write a basic HTML code, with buttons, to control R2. For this, I’ve had to go down a little rabbit hole with youtube, google and gemini, to learn how actually this stuff works. After, and along with researching, I’ve had to change a little the structure of my code, and implement new features. I also added LEDs this time! I think the coolest feature is, that R2 will tell us with Morse his IP address, using his LEDs (because he will have different ones based on which wifi network he is currently connected to, and he will have no other way to tell it us). We’ve also made some crucial changes. At first we’ve wanted R2D2 to have sounds, but we will have to omit this one for now, because our lack of time. Also, rather than random flashing, each LED will have it’s own purpose, and they all going to be used for communication.

So this time, I’ve tried to test the wireless part. I started by downloading a UDP app on my mom’s phone, and rotating the stepper motor with that, but nothing happened. After this I’ve rewritten the code so it does nothing with the motor, but prints the text in the UDP pockets, but still nothing. I’ve downloaded Packet Sender to my laptop, but still nothing. The UDP packets did never reach the Pico. I’ve tried everything the Debug Master Gemini said for more than two hours, but nothing… I think I will ask my friend who is familiar with making websites to write me a lightweight HTML page with buttons, then somehow make it connect to the motor logic. I reallyyy hope that will work.

Today I tested the battery voltage measuring feature, I last time made! I put in the batteries, wired it up, copied this specific part of the code in Thonny, told it to print the voltage, aaaannd when I checked with the multimeter, it was waaay off, lol. I was baffled, because the voltage my Pico measured was MORE than a full volt below the actual voltage. I immediately started researching, (by asking Gemini… of course…. I start to feel guilty for all the trees and water I waste), and it said to me that it is likely due to resistors are not perfect, this is why they have a TOLERANCE band, and I should start a different approach. It suggested that I should calculate a factor, by dividing the voltage of the batteries measured with a multimeter, by the raw ADC value my Pico reads, then multiply with that with the raw ADC value. After fixing this, it gave me roughly the exact value my multimeter had shown. P.S. If I could learn for once, that I HAVE to use period at decimal numbers, instead of comma, I would spend way less time searching for bugs that don’t exist…

This time, I made the main power lines of R2D2! I started by soldering 3 wires (three positive, and three ground) to the battery holder, which will be the cozy home of two 18650 Li-Ion batteries. I connected a 5 volt buck converter to one of the lines, which will power the Pico, and a voltage divider to the next one, to help the Pico measure the batteries’ voltage, and give me a warning (eventually using R2’s LEDs) of low voltage. There is not connected anything yet to the third line, because the motor driver will be powered using this, but that soldering would be really hard with my setup, and I don’t know if I could safely do it. So I think I will ask an adult acquintance of mine, who works with electronics, to do that one for me.

It’s been over a week since the last update; however, don’t let the silence fool you! 😉 In the latest grinding, I worked almost entirely on the most critical piece: the main foot. Anyone who has ever designed a functioning mechanical foot knows exactly the pain and agony, that turning a solid block into a precise assembly is a total survival trip (maybe it’s just skill issue🥀), but I’m so proud that I’ve made it so far! The perfect wheel connection is ready, and the JGA25-370’s motor mount has found its home. Even those printer-killing, razor-sharp internal overhangs got tamed with clean chamfers and fillets. R2 will be proud of our team!

This time, I tackled the main ankle block, and it’s done, and also wrapped up the design for the decorative side panels on the center foot assembly.

To keep maintenance easy and avoid visible screw holes, I separated the decorative panels and designed small pockets for 5x2mm neodymium magnets that perfectly fit into the hole.

I’m here again and I’ve just tried to finish the main leg. It’s still missing a few decorative elements.

Next I will make the shoulder attachment and after that, it’s time for R2’s head!

Hello, guys! I’m back with a huge update!

Recently, I’ve been working on finalizing R2’s legs and shoulder attachment, and it’s looking far better than expected! It’s finally starting to look truly recognizable.

It wasn’t a smooth process, though I ran into quite a few problems with component positioning and broken external links between files. Fixing lost references took a lot of patience and effort and figuring out the correct 18° body tilt and getting the shoulder alignment right was time-consuming.

Basically it’s done; however, I still haven’t figured out how to make the center wheel. I hope I’ll find the right way. Maybe I’ll have to use LEGO wheel…

This time, I’ve finally made the wireless part! I started by, as you probably guessed it already, by brainstorming with Gemini! I asked it to give me tutorials on youtube, on how to make my robot wirelessly controllable, since I have a Pico W, as well as explain it himself. At first, I’ve went down a little rabbit hole, because I wanted to build a simple website, with buttons, to control R2D2. I quickly realized after peeking into college-level tutorials, that it far exceeds my capabilities at the moment, so I asked my good ol’ friend, Gemini, to give me a bit of a simpler solution. After some deep discussions, and watching a nice old man on youtube explaining it, I decided on non-blocking UDP socket polling, with the help of an external app. This will work by downloading an app to my phone (or anyone’s phone, who wants to control R2), agreeing on an ip address, and port number, then typing the letters, which represents the w, a, s, d, etc. keys. It may not look pretty, but it’s just as effective, and MUCH simpler.

Today, I added the sensor for the homing sequence of R2’s head! This way, at startup, the head will start to turn, until it hits the infrared sensor, then go back to the middle. This way it is ensured, that no matter what position was the head at startup, it won’t go beyond the safe limits

So this time, I finally wired everything for the stepper motor-powered head together! I copyed the part which controls specifically this from my entire code sitting VSCode, just to try this out. I had an old battery holder saved from a toy, to make an external power source, and wired everything together. I checked the wiring with Gemini, to make sure I don’t light anything on fire. After this, well, it did not work… I spent brainstorming, “debugging”, and checking everything twice, until I realized the “bug” which prevented the motor spin, was the very common “missing battery” error. So I put it in, and after some fine tuning on the code, it worked really nice

This time I coded the homing sequence, which will help R2 center it’s head using the stepper motor. There will be an infrared sensor in the head, and at startup, R2 will turn its head slowly left, until the sensor detects it, and after this, the code will set the step count to 0. After this the head will automatically turn to look forward, while counting the steps. This is necessary to ensure that the head will move only in the safe limits, no matter in which position it was at startup. I took the help of Gemini at debugging.

This time, I collected multiple days’ work for this devlog. I started by brainstorming with Gemini (by now I must be their top user, lol) about what motor would be best for turning R2’s head. We’re planning LEDs in the head, so I had to make sure it cannot rotate all the way around, because this would break the wires. I came to the conclusion, that a custom 3D printed gear mechanism would be best, with a 28BYJ-48 stepper motor, and a ULN2003 board, and rotation limits in the software. I watched videos on Youtube, and also asked Gemini to explain to me how to write a code to control the stepper motor. The code is not yet complete, I’ll have to add a “homing mechanism”, which would help the head find it’s position at startup.

Today I wrote the prototype of the code, which will control the motion of R2D2. The original version will control it wirelessly, along with the sounds and ligths, but this controls only the motors yet, via a microUSB cable. I wrote it in VSCode, and I will only copy it to Thonny (which i’ll be using for the Pico) when it is fully completed. I took the help of Gemini, to explain me how to control it (the robot, eventually) using my keyboard, and with the final debugging. I also watched Electro Nerds Academy’s youtube video in the process, which explains how to control the TB6612FNG motor driver with Arduino, and C++, I did this to make sure I understand the process. I still have a lot to learn, but slowly and surely, R2 will roll!

Today, I got the Pico!!! Immediatelly I started to load up micropython on it, and download Thonny. It was a bit tricky, because my antivirus program wouldn’t let me download it, but I disabled it temporarily, and it worked just fine. And I quickly reviewed the first few pages of my PDF book, to make sure I know my Pico physically, not just the Wokwi version. After that I wanted to try it out with the onboard LED, but it didn’t worked, so I asked Gemini. I found out that my Pico, is actually Pico W, and the onboard led is a little different. After that it worked beautifully. Then I wanted to light up an external LED, and guess what, it also didn’t work! I started troubleshooting with Gemini on my side, and I found out, that my breadboard’s ground rail is probably damaged. After rewiring to bypass it, it lighted up!

A problem occurred during the delivery if the Pico, so it got retured to the sender. We had to order it again, so until it arrives, I thought I could learn actually how to control the DC motors with it, with the help of a TB6612FNG motor driver which we will be using. I asked Gemini to explain it to me, without providing exact codes, to ensure I actually understand the code, and not just copy-pasteing. It gave me a great youtube tutorial too, from Electro Nerds Academy, which used Arduino (and therefore C++), but it helped me understand the core principles of the wiring, and the code

EDIT: This was BEFORE I was aware of the rule which states that we should not log too much continuous time spent watching youtube. This was only the learning phase, and I tried making it as active as possible, by building my own version on the way. If it is against the rules, please just ignore the time logged in this post. I don’t know if it is possible, but I’m pretty freaked out my entire summer work gets flushed down the toilet😭😭