Initial Experience with the Integration of a Terrestrial Laser Scanner into the Mobile Hydrographic Multi Sensor System on a Ship

Hydrography is the science and practice of measurement and representation of the parameters necessary to describe the condition and shape of the sub-water surface, its relationship with the land surface, and the condition and dynamics of the water. To fulfil the requirements of many hydrographic applications a mobile multi sensor ship, which is able to measure all necessary parameters, must be available. Due to special conditions in the harbour of Hamburg and along the river Elbe, which is the most essential entrance for the economy of Hamburg, the monitoring of sedimentation in the harbour and the documentation of the docks is of major interest for the Hamburg Port Authority. However, these tasks require a multi sensor system, which is able to measure simultaneously above and below water.
In this paper initial experience of the integration of two terrestrial laser scanning systems, IMAGER 5006i from Zoller + Fröhlich and Riegl VZ400, into the mobile hydrographical multi sensor system will be presented. These systems have already been installed on two different ships in Hamburg. In a first pilot study the ship Level-A (length 8m, width 3.5m, draught 0.35m) from the HafenCity University Hamburg (HCU), which is well-suited for operations in shallow water areas, has been used in cooperation between HCU and the engineering office Dr. Hesse and Partner (DHPI), Hamburg to test the terrestrial laser scanner IMAGER 5006i from Zoller + Fröhlich in combination with the hydrographic sensors onboard. The second pilot study was carried out with the terrestrial laser scanner Riegl VZ400, which had been installed on the ship Deepenschriewer III (17.2m length, width 4.9m, and draught 1.4m) from the Hamburg Port Authority. For testing the sensor integration of these two multi sensor systems two objects were scanned in two selected test areas of the harbour of Hamburg and Wedel to demonstrate the performance of each system. To verify the accuracy of the kinematic laser scanning system on the ship some reference data has been scanned with static laser scanning. The system integration and test procedures including first results are described in the paper.