My Advanced Realistic Humanoid Robots Project

Ok so I had a breakthrough on communications networking within my robot. Originally I planned to have the main brains PC in the chest of the robot connect by USB to a "chest arduino" which would connect by single wire communication to a right arm arduino, left arm arduino, right leg arduino, left leg arduino, head arduino. So the chest arduino is forking out to all of those with each of those on a separate digital IO line connection with the chest arduino. This means the chest arduino was...

While on my journey to develop the firmware for the ESC so far I was trying to figure out how to implement all the features the original ESC has to offer in its hardware setup but then it occurred to me that I don't need most of that stuff. And a lot of the complexity that was in the original ESC firmware I also realize I don't have to recreate or reproduce in the C language with my own style and formatting but can just leave out entirely. I recalled that my plans for a long time prior to...

Ok so after further consideration I decided that the idea of adding significant modifications to a 6k lines of code 20 file assembly language behemoth firmware developed by a big company was just not prudent for me. I need to be able to go in there and add tweaks and improvements for years to come and maintain my code there. The firmware of the ESC is absolutely essential to get just right as it has a massive impact on the performance of the final humanoid robot. The speed and fluidity of...

It occurred to me I might be able to find more cheap ESCs in this size profile on aliexpress and I did find some offers that were far cheaper than amazon. The ones I bought on Amazon were'n't too bad on price but these were a lot cheaper but take longer to ship from China on aliexpress. Here was my haul of 11 more: Also pay special attention to the first ESC in that list. It is for $3.25 each SHIPPED and that is CHEAPER than the cost in parts to make my own motor controller from parts...

Ok so I had someone point out a very very small very very high amp ESC to me that actually would be viable from a space taken standpoint, however, it was $48 shipped which is WAY too expensive when I can make my own motor controller for $4 in parts. However, I did a search for that ESC on amazon and a very similar ESC popped up that was around same size but made in china with no US middleman and cheap amazon prime shipping which dropped the price to around $11 shipped per ESC. Now THAT is...

Ok I made my circuit design for my BTS7960 integrated half bridge IC chips. I plan to go with through hole passive components (resistors, capacitors) and use deadbug style so I can skip making a PCB this way. This will cut out that significant step and save time IMO. If I have trouble or determine later a PCB would make things go faster I can design and make one but I am happy to have a break from that for the time being and just go with deadbug again. I like deadbug method alot and think it...

Ok so I ran the test of my PCB and try as I might the PCB was dead. Totally non-functioning. And to make matters worse, I would not have any clue of where the issue is. Could a static electric discharged have bricked the IC? Could some pad have a microscopic open circuit in its joint with the IC? Could there be a hidden short or open circuit somewhere that happened at some point? I simply have no way to know or test or find this issue. And this got me to thinking... maybe a bit bigger...

I soldered on 30ga wrapping wire for testing the PCB. The 3 on the front are 5v+ from microcontroller that tells this IC to be in "on" mode, ground from microcontroller, and PWM from microcontroller. The 2 on the back side are +8v and 0v/gnd from the batteries. This was shockingly quite hard to attach these. It's all so dang tiny. Every time I soldered on 8v+, the 0v would fall off because the rear pads of the chip both get hot together. Ended up having to use uv cure solder mask to tack...

I was informed that even unused pins on the chip should have copper landing pads to solder to which will even out the forces when the whole pcb goes molten and chip is trying to auto center! It makes sense! So I added those.

On the big output landing pad on the left, I separated the attachments to each individual pin for the chip's motor output phase rather than have the landing pad be one big blob. This encourages auto centering. Something I had not considered before until someone pointed it out. Such a simple change but so obvious now that I had it pointed out to me!