Full-Stack Flight, Chapter 9: Closing Thoughts
This article is part of a 10-part series on how the Centauri Quadcopter was created. For a list of all other articles, please visit the introductory article found here.
At this stage in the series we’ve fully explored the entire Centauri ecosystem: the quadcopter, the transmitter, and the telemetry analysis program. In this final chapter I’ll share some closing thoughts on the project overall, along with a few tips that will hopefully help you if you pursue building your own!
Why do all this?
The first question I want to address is the “why do all this?” question. As you can probably tell from the series, building a fully custom quadcopter and pilot transmitter is a daunting undertaking. Financially, it may even be cheaper to buy an off-the-shelf quadcopter/transmitter pair and call it a day! And from a time-to-value perspective, you’d be looking at potentially months of research and development before ever getting in the air, versus maybe a 2-day shipping window if you buy off the shelf.
The answer is: the challenge. I, like you if you’re still reading this, am an engineer. And engineers don’t just like using things; they like making them, and understanding how they work. The off-the-shelf method gives you the quickest time to use, but you skip over the fun (and difficult) parts of building your own. And that difficult, uphill battle of figuring everything out is where the real learning happens.
The pride I felt when Scout achieved its first flight back in 2023 and then when Centauri achieved its first flight in 2025, after months of frustration, hard work, and exploring new ideas, will never be something you can purchase. And the learnings that come along the way are a great bonus!
But more than that, I think building your own quadcopter (or any robotics project for that matter) is more valuable today than it has ever been. We live in an AI era, where anybody with access to the latest AI coding agent can “fake” intelligence or capability extremely easily.
Building something complicated, in both the software and hardware world, is not something that can be replicated by a 3-minute prompt. If you want to stand out and show your intrinsic skill, talent, or knowledge, venturing into the hardware space and completing a multi-month build is a wonderful way to set yourself apart.
To go faster, slow down
Something was very different between my first attempt at a custom flight controller (Scout) and my second (Centauri): my approach to the building process.
In 2023 when I built Scout, my engineering approach was to move quickly, break things, and iterate fast until I stumbled into a problem (that’s a bit exaggerated, but you get the point). I wasn’t focused on any one part of the project for very long; I’d get one piece mostly working and then quickly move on to the next, so focused on getting “the big payoff” as soon as possible: seeing Scout fly!
That mindset caused more problems than it fixed. Building something that bridges the software and hardware world, and is as complex as a quadcopter, is very challenging. It warrants time spent early in the project planning, weighing various approaches, and then relentless attention to detail through every facet of the build. While Scout flew, I wouldn’t call it as reliable or efficient as it could have been.
Fortunately, I learned from my mistakes. About two years later when making Centauri, I was far more methodical through the entire planning, design, building, programming, and testing process. No doubt I had a burning desire to see Centauri fly after the countless hours I invested turned into days, weeks, and months. But from what I learned with Scout, I knew any rushing would only cost me in the long run, because then I’d have to carve out time to go back and fix errors that wouldn’t have been there had I just given that part of the project the time it deserved.
With Centauri I was much more methodical and detail-oriented through every part of the project. In hindsight, my approach was likely subconsciously inspired by “Gradatim Ferociter”, the motto of Blue Origin that I must have read about a decade prior. Jeff Bezos explained the motto:
“Gradatim Ferociter” is Latin for “Step by Step, Ferociously. If you’re building a flying vehicle, you can’t cut any corners. If you do, it’s going to be just an illusion that it’s going to make it faster. You have to do it step by step, but you do want to do it ferociously.”
This isn’t easy!
Let me be the first to tell you: building a custom quadcopter is not an easy feat. Even having this series and sample code to guide you, it will be challenging. If you decide to build your own iteration of Centauri, please bear this in mind. Be be kind to yourself. Take your time. This is a very daunting project, and one you likely won’t succeed at on the first try. Focus on the small things, one after another, and eventually the bigger picture will come together.
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PID tuning, shown below, is one of the most frustrating part of the building process:
And even after you have everything working, things happen!
Future Improvements
As I described in chapter 1, Centauri was already a huge upgrade over Scout, for a number of reasons. However, Centauri, at least in its current state as of this writing, is still relatively primitive in the overall landscape of quadcopters out there today.
I do plan to make further improvements to Centauri, building on this fantastic foundation. The following come to mind as immediate ideas:
- Tweak Angle Estimates: The Centauri Flight Controller uses a complementary filter to estimate the pitch and roll angles during flight. While the angles are mostly correct, there are certainly discrepancies. I’ll need to take a closer look, identify any potential errors, and then work on improving their accuracy.
- Advanced Flight Controller Modes: as I discussed in chapter 5, the Centauri Flight Controller, while impressive, is actually quite primitive in its capabilities. At some point I’d like to equip Centauri with additional hardware (sensors) and software to let it hold attitude, hold position, or even fly to various waypoints. This will be quite the undertaking!
- Handheld Transmitter: in chapter 6 I described the decision to use an “augmented” PC (laptop) as the transmitter instead of building a custom transmitter. That decision worked very well! But at some point I’d like to fly Centauri without packing up a full laptop and transceiver platform. For that, I’ll need to design, build, and implement a handheld transceiver.
- Custom PCB: as I showed in chapter 4, my first iteration of the Centauri quadcopter is rather messy. I assembled all the hardware onto the 3D-prints and then wired everything together myself. Not the best formula if you’re after a clean, sleek-looking quadcopter. At some point I’ll develop a custom PCB (printed circuit board) for Centauri that will make the final result much sleeker while saving weight (more performance and range).
Those are just the immediate big ideas that come to mind, but I’m sure many more will follow! If you have any ideas or suggestions, I’m all ears.
Join The Community!
In the three years since I released my write-up series on Scout, I’ve had so many positive interactions with members of the maker community; people that were just like me when I first sat down to build my own custom quadcopter flight controller. Messages, YouTube comments, tweets, and more.
I’m creating a space for any makers interested in building their own iteration of Centauri to share progress and ideas, ask questions, and celebrate their successes! You can join us on the Full Stack Flight Discord Server. It’s completely free to join in on the conversation!
Scan the QR code above or click here for an invite to the Full Stack Flight Discord Server!
I’ll be there too, sharing my own progress and helping answer questions from those pursuing building Centauri themselves! I hope to see you there.
Parting Thought
Building my own quadcopter, from absolute scratch, and taking flight had been a dream of mine. To build a flying machine, that would be amazing! And I remember just how hard it was pursuing this with Scout back in 2023. I remember the countless hours searching online, trying new ideas, reading over bugs, and brainstorming problems and their solutions.
If you can relate to that, I hope you’re able to find value in this series. I hope it helps you accomplish exactly what you’d like to do without the headache I experienced. In a way, this series and the entire Centauri project is a distilled version of everything I learned, packaged up for a new maker to leverage.
Use this guide! Learn and build understanding! And do something amazing. Good luck to you. 😊
