just_grassy
I design and build embedded systems for flight and robotics — from circuit board to firmware to flight dynamics — and publish the process along the way.
01 — Core Projects
Selected Work
Flight systems, embedded platforms, and research projects, ordered by priority. Status badges reflect where each project actually stands today.
Probabilistic Analysis of Drone Crash Impact Points
Rigid-body simulation-based probabilistic analysis of drone crash impact points, implemented as a Monte Carlo simulator in C99, with an embedded systems application layer.
Submitted to IEEE Robotics and Automation Letters (RA-L); received an editor reject and is being revised with additional experiments for resubmission.
Extreme-FC
A flight controller and drone platform engineered for reliable operation under extreme environmental conditions.
Drone Ground Effect Research
Research into aerodynamic ground effect behavior in multirotor drones and its implications for low-altitude flight control.
Pixhawk Auto Docking Station
An automated docking station concept for Pixhawk-based drones, enabling autonomous landing, charging, and redeployment.
CanSat (ELRS + LoRa TDMA)
A CanSat platform using ExpressLRS and LoRa TDMA scheduling for redundant, low-latency telemetry links.
Custom BEC PCB
A custom battery eliminator circuit (BEC) board designed in KiCad and fabricated through JLCPCB for regulated power delivery in flight systems.
Y-Zipper Drone Wireless Charging Alignment
A Y-zipper-based mechanical alignment guide for drone wireless charging pads, built for the Nobel 100x100 competition.
FTC Decode
Competing in the FIRST Tech Challenge (FTC) Decode season, building and programming a competition robot.
02 — Ventures
Startups & Products
Ideas taken from competition prototype to a product being actively developed.
Safe Fire
An IoT device that automatically removes a fire extinguisher's safety pin in an emergency, cutting critical response time during a fire.
Originally built with a teammate for a middle school startup competition, where it won the Ministry of SMEs and Startups Minister's Award (grand prize) and a mock funding round reached ₩270M in simulated pledges. Now being developed solo into an actual startup product.
BuildIt
An educational platform that trains code-review skills for developers who rely heavily on AI-assisted ("vibe") coding.
03 — Writing & Community
Sharing What I Learn
Technical writing and community projects built to make hard-won knowledge easier for others to find.
STM32 LL Driver Article Series
An ongoing technical article series on writing low-level (LL) drivers for STM32 microcontrollers, from register-level fundamentals to practical peripheral drivers.
04 — Platform & Team Projects
Building With Others
Infrastructure and tooling built collaboratively for the school community.
05 — Where It Started
Middle School Journey
The earlier projects that built the foundation for everything above.
Object-Picking Robot
Built a robot that extends a leg-like arm into tight, hard-to-reach spaces to pull out objects stuck deep inside — an early hands-on introduction to mechanical actuation.
IMU-Based Seismic Building Model
Learned IMU fundamentals and applied drone gimbal stabilization principles to a numerically-integrated seismic response model for earthquake-resistant building design. Won a Merit Award (우수상) in the Physics category at the 69th Chungbuk Science Exhibition.
Press coverage06 — Tech Stack