Welcome to RookiDroid!
I’m Zhengyu Peng, an engineer at Aptiv specializing in automotive radar systems. RookiDroid is my personal corner of the internet — a place where my professional engineering background meets my passion for building things with my own hands.
It all started with wanting to build cool robots for my kids. What began as a weekend hobby quickly grew into a full creative practice: designing, 3D printing, wiring, coding, and iterating until each build comes alive. Every project on this site is something I’ve personally designed from the ground up — from the mechanical structure to the firmware running on the microcontroller.
What You’ll Find Here
- Build Stories — In-depth documentation of my robot projects, including design decisions, challenges, and lessons learned along the way.
- Open-Source Code — All the software that powers these robots is freely available, so you can learn from it, modify it, and build your own.
- Custom PCBs — The circuit boards in the shop are extras from my own builds. I design every board myself, then hand-solder and test each one before it ships. No mass production, no shortcuts.
- 3D Printable Parts — Many of the structural components in my builds are 3D printed. I’ll share STL files and print settings so you can reproduce them at home.
Why the Shop Exists
Building robots isn’t cheap. PCB fabrication, quality components, tools, and filament add up fast — and every batch of boards leaves me with a handful of extras. Rather than let them collect dust, I list them here at a modest price to help offset development costs. This isn’t a business; it’s a hobby that I want to keep sustainable. If you buy a board, you’re directly helping fund the next project — and I genuinely appreciate that.
⚠️ Important: Limited Stock — No Restocks Planned
Every PCB in the shop comes from the spare units left over after my personal fab orders. I only order what I need for my own builds, so quantities are always small — typically just a few units per board. Once a board sells out, I don’t plan to reorder it. If you’re interested in something, don’t wait too long. There’s no waitlist, no backorder, and no guarantee a second batch will ever happen.
That said, if you’re comfortable ordering PCBs yourself, all my designs are open-source. You can grab the design files from my GitHub and fab your own through any PCB manufacturer — the boards will be available long after my extras are gone.
Quality You Can Trust
Since every board is assembled by hand, I take quality seriously. If you’d like to see examples of my circuit design and soldering work, check out my research project portfolio at zpeng.me/research-projects — every board shown there was also designed and hand-soldered by me.
How This Site Is Built
True to the spirit of this site, the infrastructure behind RookiDroid is also a DIY affair. This website runs on a mini PC sitting in my living room, powered by Arch Linux and Nginx, with WordPress as the backend. No cloud hosting bills, no managed servers — just a small, quiet machine humming away at home. And yes, even the server rack holding it together is 3D printed.
What makes this possible at scale is Cloudflare. Their free tier provides DNS management, DDoS protection, caching, and SSL — essentially acting as the shield and delivery layer that makes a home-hosted site feel like a professionally hosted one. I’m genuinely grateful for what Cloudflare makes available for free to hobbyists and indie makers. Without it, reliably serving this site to visitors around the world from a living room PC simply wouldn’t be practical.
About Me
By day I work on cutting-edge radar technology. By night (and on weekends), I’m in my workshop in Westfield, Indiana, soldering, printing, and building. I believe that making things — really making them, start to finish — is one of the most rewarding things a person can do. I hope this site inspires you to build something too.
To learn more about my background and professional work, visit zpeng.me.
Thanks for stopping by — I hope you find something here that sparks your next project! 🤖