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-# DenshaBekutoru - Model Train Direction Sensor
+# 電車ベクトル (DenshaBekutoru)  
 
-Get **direction** and **speed** from motor power signals.  
-Target use case: **model trains**.
+## Model Train Direction Sensor
 
-- Detects polarity (+/–) to identify train direction  
-- Measures pulse width to calculate speed (% of maximum)  
-- Implemented with optocouplers and a state machine  
-- As small as possible, but I hope no SMD (beginner friendly)
+DenshaBekutoru is a small controller board for brick-built model locomotives.
 
-Project is in an early stage. Currently running tests on target hardware.  
-More information and documentation will follow.
+The target use case is: read the motor power signals, detect the current driving direction, and switch the headlights accordingly. The software is also prepared to derive speed information from the motor signal behaviour.
+
+This project is built around one practical problem: the motor is driven from an H-bridge, so the signal is noisy, polarity changes are not “clean logic”, and inductive spikes make direct evaluation difficult.
+
+## What it does
+
+- detects train direction from the motor power signal
+- evaluates two processed motor-side signals via analogue inputs
+- switches the front / rear lights according to direction
+- keeps the last valid direction if the train stops or the signal becomes unclear
+- is designed as small as possible for installation in brick-built locomotives
+
+## Technical approach
+
+The current version is built around:
+
+- optocoupler-based input isolation and signal conditioning
+- Arduino Pro Mini 5V as controller
+- software averaging of analogue inputs
+- startup calibration to adapt to different controllers and builds
+- threshold + hysteresis logic
+- simple state machine with direction memory
+- PWM-capable output pins for possible later LED dimming
+
+The main idea is not to read one raw signal and react immediately.  
+The idea is to turn a noisy motor signal into a stable direction decision.
+
+## Current status
+
+**Version 2 (beta) is built and working.**
+
+Current state:
+
+- [x] schematic finished
+- [x] PCB finished
+- [x] firmware finished for the current beta state
+- [x] three PCBs built and tested
+- [x] first boards handed over for real-life testing in a model railway club
+- [ ] Feedback and what to improve
+
+## Design goals
+
+- as small as possible
+- beginner-friendly where possible
+- no SMD if it can reasonably be avoided
+- easy to reproduce later as a DIY kit
+- modular PCB concept with main section, future-option section, and test section
+
+## Repository content
+
+Typical content of this repository:
+
+- `KiCad/` – schematic and PCB files
+- `firmware/` – Arduino test and controller software
+- documentation and pictures will be added step by step
+
+## Project status note
+
+This is still a beta project.
+
+The current hardware and software already work, but testing on real locomotives is still ongoing.  
+The next version will depend on real-life feedback from actual use.
+
+Possible next steps:
+
+- verify behaviour with different motor controllers
+- check robustness in real train builds
+- improve wiring / connector handling
+- finalise optional features like LED dimming
+- prepare a first “official” DIY kit version
+
+## Blog / documentation
+
+- Project overview:  https://togo-lab.io/?p=223
+- Hardware description:  https://togo-lab.io/?p=233
+- Software description:  https://togo-lab.io/?p=243
+
+## Short summary
+
+DenshaBekutoru is a small Arduino-based direction sensor for brick-built model trains.
+
+It reads the noisy motor signal from an H-bridge-driven setup, isolates and evaluates it, and switches the headlights automatically.
+
+The current beta version is working and now entering real-life testing.
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