Add DhruvaNav autonomous exploration controller
New navigation controller implementing frontier-based exploration for the
VacuumTiger robot vacuum. Key features:
Multi-threaded architecture:
- Sensor thread (~100Hz): UDP sensor reading, odometry, safety checks
- Mapping thread (~5-10Hz): VastuSLAM scan matching, grid updates
- Exploration thread (~20Hz): Frontier detection, path planning
Path planning:
- Theta* any-angle pathfinding (smoother than A*)
- SIMD-optimized cost map with obstacle inflation
- Path smoother for differential-drive kinematics
Frontier exploration:
- Flood-fill clustering of frontier cells
- Normalized scoring (distance, size, info gain)
- Blacklisting and recovery for stuck situations
Integration:
- SangamIO TCP/UDP client for robot communication
- VastuSLAM for SLAM and occupancy grid mapping
- SVG visualization with trajectory and frontier markers
codetiger
397eee1455