Occupancy Map Viewer

Real-time viewer for occupancy grid maps with coordinate overlay, published by Hammerhead's GridDetect feature.

Installation

pip install -e examples/python/occupancy_map_viewer

Usage

python occupancy_map_viewer.py <src_ip>

Parameters

  • src_ip: IP address of the device running Hammerhead

Examples

# View occupancy map from local device
python occupancy_map_viewer.py 127.0.0.1

# View occupancy map from remote device
python occupancy_map_viewer.py 10.10.1.10

Features

  • Binary occupancy grid visualization (white = occupied, black = free)
  • Grid overlay with 10-meter spacing in physical coordinates
  • Coordinate labels in margins (red for X-axis lateral, green for Z-axis depth)
  • Real-time frame statistics: timestamp, grid dimensions, occupied cell count
  • Metadata display: grid bounds (xMin, xMax, zMin, zMax) and cell size

Prerequisites

Important: Enable GridDetect in Hammerhead configuration:

  • Set enable_grid_detect = 1 in master_config.ini
  • This automatically enables occupancy map publishing via ZMQ (port 9900)

Topic Information

Topic Port Description
nodar/occupancy_map 9900 Binary occupancy grid (CV_8UC1) with metadata

Troubleshooting

  • No display appears: Check that enable_grid_detect = 1 in master_config.ini
  • Connection timeout: Verify network connectivity and that Hammerhead is running

Press Ctrl+C to exit the viewer.