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.
GES: Ground Effect Stabilizer — Onboard-Sensor-Based Feedforward Estimation of Ground Effect on Irregular Terrain via Machine Learning versus Analytical Models
Onboard-sensor-based feedforward estimation of ground effect over irregular terrain, comparing machine learning and analytical models for multirotor flight.
Rigid-Body Simulation-Based Probabilistic Analysis of Drone Crash Impact Points and Its Embedded System Application
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.
Samara Autorotation Descent Research
Study of samara-inspired autorotation for controlled, power-free descent, exploring passive stabilization strategies for small flight vehicles.
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.
Cutist
An adaptive Pomodoro-style study assistant that adjusts session timing to focus patterns, presented at the IEEE SSCS Arduino Contest.
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.
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 fixes the code-review skill gap from AI-assisted ("vibe") coding, teaching top-down from real code to review fundamentals.
Launched publicly on Product Hunt and X on August 6, 2026.
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
A technical article series on writing low-level (LL) drivers for STM32 microcontrollers, from register-level fundamentals to practical peripheral drivers.
IESBJ
A student-run technical journal that I built and operate, publishing engineering and science writing by students.
04 — Team Projects
Building With Others
Every project I've built as part of a team, from a delivery robot to school-wide platform tooling.
FTC Decode
Competing in the FIRST Tech Challenge (FTC) Decode season, building and programming a competition robot.
cbgpu
An all-in-one school life platform — GPU rental and server deployment alongside class timetables, self-study room applications, meal menus, discussion boards, study groups, and voting, all in one place.
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 in the Physics category at the 69th Chungbuk Science Exhibition.
06 — Tech Stack
Tools I Build With
Languages
Embedded
Flight & Autonomy
AI & Compute
Dev Tools
Frameworks & Collab
Linux & Systems
07 — Certificates
Always Learning
Claude Code in Action
Anthropic · Aug 2026
Claude 101
Anthropic · Aug 2026
NYPC 2025 — Round 2 Special Award
NEXON · Oct 2025
NYPC 2025 — Round 1
NEXON · Oct 2025
SW·AI Education Essay Contest — Grand Prize
Ministry of Science and ICT / KOFAC · Oct 2023