
The CAST Gauge is a visual and numerical tool that will assist the hydrographer in deciding when to make a sound speed cast, how deep the cast should be, and at what times the casts should be executed. All based on the survey requirements. The CAST Gauge is an innovative technology that integrates the science behind the "uncertainty wedge", originating from research at the Ocean Mapping Group, University of New Brunswick, and that of the Total Propagated Uncertainty (TPU) with respect to refraction.
Sound speed through the water column is an important component to determining the Total Propagated Uncertainty (TPU) of a sounding. If correct modeling of refraction is not implemented then large errors can result in the sounding horizontal position and depth.
Ian Leblanc, ODIM MVP Product Manager says: "The introduction of the Moving Vessel Profiler (MVP) has shown that sound speed profiles can be collected at a high spatial and temporal resolution while the survey vessel is under way. This, in turn, leads to less uncertainty as well as significantly reducing post-processing time."
However, optimization of the entire multibeam data collection system is required in order to minimize maintenance costs as well as to apply effective survey planning and procedures. Therefore, efficient use of the MVP is necessary to ensure the collected multibeam data is adequately corrected for refraction to the point where customer accuracy requirements are achieved.
Mark Smith, Manager of ODIM Brooke Ocean's After Sales and Service comments: "All our new MVP systems will have the CAST Gauge implemented. In addition, all existing systems are being offered this technology as upgrades."