94 lines
2.7 KiB
Markdown
94 lines
2.7 KiB
Markdown
# Samson eFit Module – Internal README (MVP Implementation)
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## Purpose
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Build a compact, motor-controlled resistance unit with basic wireless control and encoder-based feedback.
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Stay within MVP scope and avoid feature creep until core functionality works.
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---
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## MVP Core Goals
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- Smooth electronic resistance using BLDC + driver
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- Wireless control of load (ESP32 → PWM)
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- Encoder-based feedback to maintain commanded resistance
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- Basic safety limits (current/thermal)
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- Minimal UI (phone/Pi/serial)
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---
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## Current Components (Received)
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| # | Component | Purpose | Notes |
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|---|-----------|---------|------|
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| 1 | Waveshare 4" Round DSI Touch Display | UI | Use later; not MVP-critical |
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| 2 | AS5600 Magnetic Encoders (5 pcs) | Angle/rep sensing | High priority for control loop |
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| 3 | Milwaukee M18 Battery Adapters (2 pcs) | Power source | Portable demos; regulate as needed |
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| 4 | 400W BLDC Motor Controllers (2 pcs) | Motor driving | PWM control with FWD/REV/Brake |
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---
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## High-Level Architecture (MVP)
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- **ESP32**: PWM output + encoder reading + wireless interface
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- **BLDC Driver**: Drives motor phases based on PWM
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- **AS5600 Encoder**: Shaft position/velocity feedback over I²C
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- **Power**: 18V battery via adapter (regulate for ESP32)
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- **UI**: Minimal (phone > Pi display for later)
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---
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## Implementation Order (Milestones)
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1) Bench-test BLDC controller + motor (no load)
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2) Read encoder position/velocity reliably
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3) Close feedback loop (PWM adjusted from encoder)
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4) Add safety limits (brake/stop/overcurrent handling)
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5) Wireless interface to set target resistance
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6) Optional: Pi display UI after stable MVP
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---
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## Firmware Tasks (ESP32)
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- PWM generation + tuning
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- Encoder I²C driver (AS5600)
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- Resistance control loop (angle/speed → PWM adjust)
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- Safety watchdogs (fault detection)
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- Simple wireless command interface
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---
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## Hardware Tasks
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- Encoder magnet mounting on pulley/shaft
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- Secure motor + driver on bench fixture
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- Power routing + regulation
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- Fusing + emergency stop provisions
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---
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## Power Notes
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- M18 battery: 18V nominal
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- Driver acceptable: 6–60V
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- ESP32 requires regulated 5V/3.3V
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- Add DC-DC regulator if powering both from same source
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---
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## Scope Limiters (Avoid Feature Creep)
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Not MVP:
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- Full AI workout planning
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- Cloud accounts or server database
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- Advanced touchscreen interface
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- Subscription model
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MVP success = controllable electronic resistance + encoder feedback loop.
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---
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## Testing Targets
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- Commanded resistance holds within stable margin
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- Encoder data noise acceptable
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- No uncontrolled torque spikes
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- Safe stop behavior verified
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---
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## Notes to Ourselves
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If it does not directly help us **control and stabilize resistance**, it waits until after MVP.
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