Warunika Ranaweera, Shazan Jabbar, Ruwan Wickramarachchi, Maheshya Weerasinghe, Naduni Gunathilake, Chamath Keppitiyagama, Damitha Sandaruwan, Prabath Samarasinghe University of Colombo School of Computing

 Virtual maritime simulation systems to train mariners  Conventional Vs. Virtual maritime training o Cost effective o Safe o Effective for the trainee? Onboard and virtual maritime training

 Maritime navigational simulator to train naval officers Vidusayura : a maritime ship simulator

 Radar  ECDIS Chart plotters  AIS  Telescopes  Etc. Marine onboard equipments

 Standalone radar simulations o Less effective  Radar simulation for virtual environments o Signal processing o Ray casting (ABC et al.) o 3D models o Complex calculations Radar simulation

The need for a light-weight marine radar which operates on the real time data feed from the virtual environment Motivation

 A tool for navigation o Determines the distance for surrounding objects o Graphical representation  How it works? 1.Emitting electromagnetic waves & catching the reflection 2.Displaying height variations up to the maximum height  Radar sweep Marine radar

 Mimicking the wave propagation method in a virtual environment o Requires better machine performance  Our approach: o Light-weight o Compatible with commodity, low performance, computers Radar simulation for virtual environments

 A different method to detect surrounding objects  Gathering geographical information (heights) using a Heightmap o 2D interpretation of a 3D terrain o Grayscale image, with black representing the minimum height and white representing the maximum height  Gathering object positions from the virtual world o Own ship position o Surrounding ships & obstacle positions  Open access to the source – adaptable to the changes in the virtual model Radar simulation: a lightweight approach

Design of the virtual radar Geographical information Geographical information Object positions “Pixel Matrix” Marine radar Maximum height 000 Finding max heights along the radius

Implementation 1. Pre-processing the height map image o Extract the pixel values and insert into the “Pixel Matrix” 2. Retrieval of the real time object position updates o Retrieve from the Vidusayura server application o Scale the positions to the “Pixel Matrix” 3. Maximum height detection of the “Pixel Matrix” o Detecting the maximum height along straight line in a specific moment

Maximum Height Detection Pixel Matrix Bresenham’s Line Drawing Algorithm  Performing a circular search on the “Pixel Matrix” Max Height Detection Algorithm

Implementation 4. Representing the dynamically moving ship o Tying the origin of the radar view to the own ship’s position o Always map all coordinates to the mid point 5. Displaying the output o Generate images from the “Pixel Matrix” and view as an image stream

Discussion and Results  Virtual radar coverage nearing the Galle harbor

Discussion and Results  Virtual radar coverage is well synchronized with, o The own ship position in the virtual environment o The own ship positions in the ECDIS o Real world radar in a similar situation

Discussion and Results  Virtual radar coverage is well synchronized with, o The own ship position in the virtual environment o The own ship positions in the ECDIS o Real world radar in a similar situation

Discussion and Results  Virtual radar coverage is well synchronized with, o The own ship position in the virtual environment o The own ship positions in the ECDIS o Real world radar in a similar situation

Discussion and Results Virtual Radar Coverage ECDIS Chart Plotter Vidusayura virtual maritime environment Real Radar Coverage

Future Work  Adjusting the range of the radar coverage according to the user perception  Considering the atmosphere, different weather conditions and material of the reflecting object  Integrating a sonar for undersea obstacle detection

Thank you!