A laser range-finder scanner system for precise manoeuver and obstacle avoidance in maritime and inland navigation

A new maritime navigation system based on a laser range-finder scanner is described in this paper. Initially, the advantages of the Ladar system over the existing radar techniques are outlined. Then, the requirements of the Ladar regarding angles of exploration, measurement range and precision for different kinds of maritime operations are analysed. The principal components of this system: the laser range-finder, the scanning unit and the data processing and displaying unit, are described in detail giving their main characteristics. The Ladar pseudoimage formation process is described. These images are then processed for the extraction of features of interest, which are continuously tracked for obstacle avoidance and precise manoeuver operations using Kalman filtering techniques. Finally, sets of test are performed in different scenarios: open-sea navigation including entering the port and pier, and river navigation approaching bridges and locks. Some problems are identified, related to the maximum range achievable, the density of Ladar image, and other minor aspects, which need more work to be solved, but in general the results are quite promising and encourage us to continue working in this direction.