Research Task 16 Multi sensor integration and comparison.

PhD position. Bremen, Germany with secondments to IOW (Germany) and PML (UK) Supervisors: Prof. Gerhard Bohrmann, Dr Christoph Waldmann, Dr. Douglas Connelly, and Dr Ralf Prien.

The objective of this research task is to develop standard procedures for integrating multiple sensors into systems such as autonomous underwater vehicles (AUVs), remotely operated vehicles (ROVs) or seafloor and mid-water marine observatories. In particular a scanning sonar system will be integrated into a multi sensor package and the according platforms to demonstrate interoperability.. The challenges facing the establishment of a coherent data capturing system are considerable, for example data heterogeneity, sampling rate, data scalability, precision, accuracy and cross-calibration. One approach is to integrate sensors elementally, using a software-enabled microcontroller system. It would establish a common data protocol for future systems to adopt, enabling a plug-and-play commonality for the wide variety of emerging sensors. Sensor comparison is another issue, one requiring development of standard analytical procedures that can be used to cross-calibrate sensors between platforms. In order to implement the concepts of multi-sensor integration they will be embedded into the multi-disciplinary research activities at methane seeps at MARUM as well as the investigations of hydrothermal vents at NOC. These settings are characterized by small-scale temporal and spatial heterogeneity that require multi-disciplinary approaches resulting in a great variety of sensor data recorded at the same time. For example, the gas flux sites of gas emanation at the seafloor can be quantified using a horizontally-looking sonar.⁽¹⁾ There is evidence that the gas flux varies with changing hydrographic parameters and that, subsequently, the amount of dissolved methane in the water column fluctuates as well. In order to put the multi-sensor integration and standardization procedures into practise, the first operational fully integrated sensor package will consist of a scanning sonar, a methane sonar, an oxygen sensor and a CTD in order to quantify the gas flux. Upon successful deployment, the standardization procedures will be adapted to further sensor systems. With the described concept at hand an efficient fusion of the collected data will be possible taking the different principles, sampling rates and ranges into account.

⁽¹⁾ Nikolovska, A., et al. 2008. G3, 9, doi:Q10010