sl-controls 413810e6ba feat(tank): SaltyTank tracked-vehicle ESC driver (Issue #122)
- kinematics.py: tank_speeds with slip compensation (angular_cmd scaled
  by 1/(1-slip_factor)), skid_steer_speeds (no slip), speed_to_pwm,
  compute_track_speeds (2wd|4wd|tracked modes, ±max clip), expand_to_4ch,
  odometry_from_track_speeds (angular scaled by (1-slip_factor) — inverse
  of command path, consistent dead-reckoning across all slip values)
- tank_driver_node.py: 50 Hz ROS2 node; serial P<ch1>,<ch2>,<ch3>,<ch4>\n;
  H\n heartbeat; dual stop paths (watchdog 0.3s + /saltybot/e_stop topic,
  latching); runtime drive_mode + slip_factor param switch; dead-reckoning
  odometry with slip compensation; publishes /saltybot/tank_pwm (JSON) +
  /saltybot/tank_odom
- config/tank_params.yaml, launch/tank_driver.launch.py, package.xml,
  setup.py, setup.cfg
- test/test_tank_kinematics.py: 71 unit tests, all passing (includes
  parametric round-trip over slip ∈ {0.0, 0.1, 0.3, 0.5})

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
2026-03-02 09:14:37 -05:00
..

Jetson Nano — AI/SLAM Platform Setup

Self-balancing robot: Jetson Nano dev environment for ROS2 Humble + SLAM stack.

Stack

Component Version / Part
Platform Jetson Nano 4GB
JetPack 4.6 (L4T R32.6.1, CUDA 10.2)
ROS2 Humble Hawksbill
DDS CycloneDDS
SLAM slam_toolbox
Nav Nav2
Depth camera Intel RealSense D435i
LiDAR RPLIDAR A1M8
MCU bridge STM32F722 (USB CDC @ 921600)

Quick Start

# 1. Host setup (once, on fresh JetPack 4.6)
sudo bash scripts/setup-jetson.sh

# 2. Build Docker image
bash scripts/build-and-run.sh build

# 3. Start full stack
bash scripts/build-and-run.sh up

# 4. Open ROS2 shell
bash scripts/build-and-run.sh shell

Docs

Files

jetson/
├── Dockerfile              # L4T base + ROS2 Humble + SLAM packages
├── docker-compose.yml      # Multi-service stack (ROS2, RPLIDAR, D435i, STM32)
├── README.md               # This file
├── docs/
│   ├── pinout.md           # GPIO/I2C/UART pinout reference
│   └── power-budget.md     # Power budget analysis (10W envelope)
└── scripts/
    ├── entrypoint.sh       # Docker container entrypoint
    ├── setup-jetson.sh     # Host setup (udev, Docker, nvpmodel)
    └── build-and-run.sh    # Build/run helper

Power Budget (Summary)

Scenario Total
Idle 2.9W
Nominal (SLAM active) ~10.2W
Peak 15.4W

Target: 10W (MAXN nvpmodel). Use RPLIDAR standby + 640p D435i for compliance. See docs/power-budget.md for full analysis.