Navigation System

The autonomous navigation system is the core of Pangolin AT-1's intelligence. Fully developed in-house from hardware to algorithms, it delivers reliable centimeter-level positioning across both indoor and outdoor environments.

Outdoor Navigation: RTK + Global Planning

RTK Positioning

Real-Time Kinematic (RTK) differential correction provides centimeter-level absolute positioning:

• Base Station: Receives satellite signals at a known fixed location
• Rover (Vehicle): Receives both satellite signals and correction data from the base station
• Accuracy: Horizontal ±0.8 cm, vertical ±1.5 cm (open sky conditions)
• Update Rate: Up to 20 Hz for real-time position tracking

Path Planning

The global path planner automatically computes optimal routes:

• A* and Dijkstra-based algorithms for shortest-path computation
• Terrain cost maps integrate traversability analysis
• Multi-point cruise and timed loop operation modes
• Dynamic re-planning when obstacles block the original path

Indoor Navigation: Laser SLAM

SLAM Mapping

Simultaneous Localization and Mapping (SLAM) enables operation in GPS-denied environments:

• No Pre-Installed Infrastructure: No beacons, markers, or reflectors required
• 2D/3D Mapping: Choose between efficient 2D grid maps or detailed 3D point clouds
• Map Editing: Modify, annotate, and manage multiple maps in the control terminal
• Multi-Map Support: Store and switch between maps for different floors, buildings, or zones

Indoor Positioning Accuracy

Multi-Sensor Obstacle Avoidance

Sensor Fusion Stack

1. 3D LiDAR: Primary obstacle detection, 360° horizontal FOV, range up to 30 m
2. Depth Camera: Close-range supplement, excels at detecting low obstacles, glass, and overhanging objects
3. IMU: Inertial measurement for heading, tilt, and acceleration compensation
4. Wheel Odometry: Dead reckoning fused with visual and inertial data

Dynamic Obstacle Handling

• Real-time detection and classification of moving objects
• Predictive trajectory estimation for crossing objects
• Safe stopping distance maintained based on vehicle speed
• Alternative path computation when path is blocked

Indoor-Outdoor Seamless Switching

The positioning fusion engine monitors signal quality from RTK and SLAM sources simultaneously. When transitioning between environments (e.g., driving from a warehouse through a door to an outdoor yard), the system:

1. Detects degrading RTK fix quality as the vehicle moves indoors
2. Smoothly increases SLAM weighting while decreasing RTK weighting
3. Maintains continuous position estimate during transition
4. Reverses the process when moving back outdoors

This transition is fully automatic and requires no operator intervention.