Kb/feature/add tactile sensing and haptic feedback

.github/workflows/ci.yml

@@ -11,13 +11,13 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
+      - name: Install system deps
+        run: sudo apt-get update && sudo apt-get install -y libudev-dev pkg-config liblgpio-dev
+
       - uses: prefix-dev/setup-pixi@v0.9.4
         with:
           cache: ${{ !env.ACT }}
 
-      - name: Install system deps for AHControl (Rust)
-        run: sudo apt-get update && sudo apt-get install -y libudev-dev pkg-config
-
       - name: Run pre-commit
         run: pixi run pre-commit run --all-files
 

.gitignore

@@ -13,3 +13,8 @@ target/
 Demo/out/
 out/
 *.code-workspace
+
+# Log, CSV, and HTML plot files
+*.log
+*.csv
+*.html

Demo/Sensors/README.md

@@ -0,0 +1,147 @@
+# AmazingHand — Sensors
+
+## Files
+
+| File | Description |
+|---|---|
+| `config.toml` | Shared config — GPIO pins, SPI settings, sensor channels, logging and visualisation defaults |
+| `ads1256.py` | ADS1256 driver — 24-bit, 8-channel |
+| `tactile_sensing.py` | `TactileSensor` wrapper — reads config.toml and drives the ADS1256 |
+| `tactile_sensing_post_visualize.py` | Offline Bokeh visualisation of logged CSV data |
+| `haptic_coin.py` | `HapticCoin` PWM class for the QYF-740 coin motor |
+
+---
+
+## FSR Tactile Sensing (ADS1256)
+
+### Hardware
+
+- **ADC HAT**: [Waveshare High-Precision AD HAT](https://www.waveshare.com/wiki/High-Precision_AD_HAT)
+  - ADS1256: 24-bit, 8 single-ended channels, SPI
+- **Sensors**: FSR (Force Sensitive Resistors) wired in a voltage-divider circuit with a **5.1 kΩ resistor** in series with each FSR to each ADC input channel.
+
+### FSR Wiring Diagram
+
+![FSR Wiring Diagram](images/fsr_wiring_diagram.png)
+
+### SPI Wiring (BCM pin numbers, set in `config.toml`)
+
+| Signal | BCM | Pi header pin |
+|---|---|---|
+| MOSI (DIN) | GPIO 10 | Pin 19 |
+| MISO (DOUT) | GPIO 9 | Pin 21 |
+| SCLK | GPIO 11 | Pin 23 |
+| CS | GPIO 22 | Pin 15 |
+| RST | GPIO 18 | Pin 12 |
+| DRDY | GPIO 17 | Pin 11 |
+
+Enable SPI on the Pi:
+```bash
+sudo raspi-config  # Interface Options → SPI → Enable
+```
+
+### Install dependencies
+
+```bash
+pixi install
+```
+
+To add a single package interactively:
+
+```bash
+pixi add --pypi lgpio
+```
+
+### Run
+
+**GUI (default):**
+```bash
+pixi run python -m Demo.Sensors.tactile_sensing
+```
+
+**Terminal only (no GUI window):**
+```bash
+pixi run python -m Demo.Sensors.tactile_sensing --terminal
+```
+
+See all flags:
+```bash
+pixi run python -m Demo.Sensors.tactile_sensing --help
+```
+
+### Offline Visualization
+
+Run without arguments to automatically load the **latest** `tactile_*.csv` from the log directory configured in `config.toml` (`[logging] log_dir`):
+
+```bash
+pixi run python Demo/Sensors/tactile_sensing_post_visualize.py
+```
+
+To visualize a **specific file**, pass it with `--file`:
+
+```bash
+pixi run python Demo/Sensors/tactile_sensing_post_visualize.py --file Demo/Sensors/logs/tactile_20260101_120000.csv
+```
+
+See all flags:
+
+```bash
+pixi run python Demo/Sensors/tactile_sensing_post_visualize.py --help
+```
+
+CSV schema (long format — one row per channel per sample):
+
+```
+sensor_time, channel, raw, volts, force_norm
+```
+
+### Tuning `fsr_r_fixed`
+
+The `fsr_r_fixed` parameter must match the resistor you place in series with each FSR to form the voltage divider. The build uses **5 100 Ω (5.1 kΩ)**. Larger values increase sensitivity at low force; smaller values increase the measurable force range.
+
+---
+
+## Haptic Coin (QYF-740)
+
+### Pin conflict warning
+
+The ADS1256 tactile sensing stack claims the following BCM GPIO pins.  **Do not assign the HapticCoin to any of these:**
+
+| BCM | Use |
+|---|---|
+| GPIO 8 | SPI0 CE0 (kernel) |
+| GPIO 9 | SPI0 MISO |
+| GPIO 10 | SPI0 MOSI |
+| GPIO 11 | SPI0 SCLK |
+| GPIO 17 | ADS1256 DRDY |
+| GPIO 18 | ADS1256 RST |
+| GPIO 22 | ADS1256 CS |
+| GPIO 23 | ADS1256 CS_DAC |
+
+Safe choices for the PWM output include GPIO 12, 13 (hardware PWM), 24, 25, 26, 27, or 35.
+
+### Wiring — [RPi 5 pinout](https://vilros.com/pages/raspberry-pi-5-pinout)
+
+![Raspberry Pi 5 GPIO Pinout](images/rpi5_pinout.jpg)
+
+| Motor wire | Pi pin |
+|---|---|
+| GND | Pin 6 |
+| VCC | Pin 2 (5 V) |
+| PWM | Pin 35 (GPIO 19) |
+
+### Usage
+
+```python
+from Demo.Sensors.haptic_coin import HapticCoin
+
+motor = HapticCoin(gpio_pin=19)
+motor.vibrate_once(intensity=0.8, duration_s=0.5)
+motor.cleanup()
+```
+
+Run the example test script as a module so relative imports resolve:
+
+```bash
+pixi run python -m Demo.Sensors.haptic_test
+```