sl-controls 432d5cb267 feat: person-following control loop (Phase 2b)
Adds saltybot_follower ROS2 package — proportional person-following
controller that bridges sl-jetson's /person/target detections to Nav2
/cmd_vel, with the cmd_vel_bridge_node (PR #46) providing safety wrapping.

Controller features:
  - Proportional control: linear.x ∝ distance error, angular.z ∝ bearing
  - Follow distance: 1.5m default with ±0.3m dead zone (no jitter at target)
  - Max speed: 0.5 m/s linear, 1.0 rad/s angular (conservative for balance)
  - Obstacle override: zeroes forward cmd_vel when Nav2 local costmap
    detects obstacle in forward corridor; turning still allowed
  - Lost-target state machine:
      FOLLOWING  → person visible
      STOPPING   → lost > 2s, publish zero
      SEARCHING  → lost > 5s, slow rotation (0.3 rad/s) to re-acquire
  - Mode integration: follow_enabled param (toggle via ros2 param set)
    independently gates the controller; cmd_vel bridge gates on md=2

Deliverables:
  saltybot_follower/person_follower_node.py   — ROS2 node (314 lines)
  config/person_follower_params.yaml          — all params documented
  launch/person_follower.launch.py            — all params as launch args
  test/test_person_follower.py                — 53 pytest tests, no ROS2
  package.xml / setup.py / setup.cfg          — package metadata

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
2026-02-28 23:22:49 -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.