My Advanced Realistic Humanoid Robots Project

I was randomly talking to chatgpt about how I have been feeling burdened by having to make my own BLDC motor controllers for my robot lately and it randomly mentioned integrated half-bridge power modules as something I could use to cut down on my labor load in making these motor controllers. This immediately stood out to me as something I'd never heard of and something intriguing. I have so far been working on my lowside switch and highside switch which together form a half bridge. Many...

So I did manage to add a pair of braided solder wick wire as a added layer over the nickel strips of the highside mosfet setup and I insulated that with red electrical tape folded over it. I also insulated everything else in sight for the most part. I lost the original control circuit so I made the replacement flat flex pcb style which should be more robust. I also added a yellow 30ga wire for the 20v input line of the gate pin of the main mosfet. I also got my fiberglass window screen mesh...

I used my jumbo Weller W100P soldering iron to attach my 6 solder wick braids to the back of the highside mosfet today and it attached instantly without a hitch. I used low temp solder paste liberally between the two on both surfaces then with my left hand smashed then together with the tip of a xacto knife pressed down onto the solder wick braids from the back. Then I brought in the giant soldering iron and it liquefied the solder in about 1 second despite all that metal involved because it...

I did some research of some loose ends today on chatgpt and discovered that my .1mm x 4mm x 60mm sections of nickel strip on my bldc motor controllers that run from the battery to the motor controller mosfets and from the mosfets out to the motor are too high in resistance and at 30a they would within a few seconds get so hot that they would desolder my low temperature solder paste. So to solve this I will be placing two side by side solder wick braids hugging the underside of the nickel...

Ok here's the populated board. I tested it with 5v positive and ground and the LED came on so it is for sure not shorting and has continuity so is most likely all working. The next test will be the full low-side switch with this board acting as the drive of the main mosfet for the switch. And once that is validated we can test the entire half bridge (both high and low-side switches). If that checks out, it's all rinse and repeat to make the full motor controller (which is just 3 total half...

I successfully made a viable flex pcb on my second attempt. I started by printing the circuit onto a mailing envelope using my laser printer. Then I taped a piece of toner transfer paper for pcbs shiny side up directly over where the print on the envelope was. This way I could use just a tiny bit of the expensive toner paper and know the printer would hit that exact spot again when I reload the envelope in the same spot. The print landed right on the toner transfer paper according to...

So armed with my successful electronic test of my prototype highside switch with driving circuit all passing, I determined now it is sufficiently validated to go through the process of converting it into a printable schematic and doing the whole DIY flat flex PCB making and acid etching process to streamline the development of the rest of the motor controller and most likely many more motor controllers as well. I opted to use photoshop as my circuit making software of choice as I'm very...

I just tested the positive high-side switch portion of the motor controller and everything seems to be working as intended. The section including all parts involved is circled in a bold blue line to indicate the portion I just tested successfully. One issue I'm having though is that the drain of the A09T attaches to the 100ohm resistor tightly and is a weak point that broke off twice now. Hardly any wiggling at all on the arduino input line and ground line leading into the A09T mosfet...

Here's the thermal tape I bought for mosfet heat sinking off Amazon:

Okay so here I have attached the LED and resistor pair with their 30ga wire wrapping wire onto my highside mosfet's front face. I may add conductive silver paste to the wire wraps in the future if any issues come up there. However, I am wondering if just tightly wrapping it in electrical tape would more or less guarantee the connection doesn't open circuit. We'll see. I also finished soldering together six braided copper solder wick strands which will act as my heatsink for my highside...