G90ak Edition OSR2+ - Introducing Custom PCB/Power Bus

Wanted to show ya’ll what I’ve been working on for the past few weeks. I’ll preface this with that this will not be remotely exciting for 99.9% of you, but I’ve been thinking of doing this for a few years and finally got off my ass and did it!

The problem:
The OSR2+ has several electric/electronic components which all need to squeeze into the small-ish chassis.

  1. Power jack
  2. Power button
  3. ESP32 logic board
  4. Power bus
  5. Servo hookup

I always wished I could eliminate several of those components in an efficient and reliable way.

Those familiar with my g90ak Edition OSR2+ know that I feel that it is SUPER important to not modify the servo wires. Shortening, splicing, or removing the wires from the Dupont connector are no-nos to me since they may void servo warranties and make it difficult to return/exchange to a retailer. My solution before was to make short servo plugs coming from the power bus, but making those was time consuming and potential points of failure. Moreover, these servo hookups ARE additional wires in the OSR2+. I tried to keep them as neat as possible, but I felt like I could do better.

The dream:
I’ve seen others build custom PCBs for the SR6 and OSR2. They were often very feature rich and large - straying from my minimalist philosophy of maximizing simplicity and reliability. My ultimate desire was a low profile and minimal solution that act as a power bus and route servo signals straight to the ESP32 board and allowing servos to be plugged in directly.

The solution:
After several years of wishing someone would create one, I finally got off my ass and began to learn VERY basic PCB design. You basically choose the components you expect to use, design a schematic, and then design your PCB. After that, you send the design file to a manufacturer and a few days/weeks later, you have a PCB in your hands.

After a few weeks of going through various iterations and live prototypes, I’ve landed on a version 1.0 design of my PCB that I wanted to show off. This PCB sits directly on top of the ESP32 like a hat and does all the power and signal routing to the servo plugs at the rear.

These will be going into all of my OSR2+'s that are sold from June onwards. I want to be clear that the g90ak PCB will not improve performance, but will make for better reliability and easier servo swaps upgrades.

Look how clean this is!

And with servos installed (I wish servos had shorter cables, I do my best)


Yeah this turned me on a little, not gonna lie :stuck_out_tongue_closed_eyes:


Cable management is my #2 turn on :slight_smile:


That’s clean!

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A similar product exists for the SR6. Without it I probably never would have finished the project. Takes out a lot of the fiddly wiring that comes with building one of these and makes things so much neater internally.

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Can I get info sent on obtaining one of these? Awesome work!

PCB is only available in the OSR2+s I sell :slight_smile:

Details on those is here.

Kinda want to upgrade my osr2 g90ak version now.

Do you know the max power able to go though the pcb? I know traces can get real hot with lots of power going though them. To the point of burning off the pcb and making magic smoke.

Haven’t calculated the max power, but I’ve done testing across a month with my own unit, as well as an hour of bench testing… The PCB doesn’t get warm at all.

I’m running a 100mil wide trace for power and ground on the bottom layer of the PCB. All signals are run on the top layer. I ran signal traces at 90 degree crossing points to power/ground wherever possible in order to avoid interference (don’t know if that makes a difference, but a habit from my car audio days).

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