Posted on 15.11.2010 - 11:00 UTC in SURVEY NEWS by Rons_ROV_Links
CDL are pleased to announce the launch of the magnetic heading aiding module for our low costs MEMS based motion sensor MiniSense2.
Magnetic heading can be derived from 3 magnetic field sensors mounted orthogonally and the technology is very mature, often giving heading accuracies equivalent to far more expensive optical systems. It does however suffer from poor dynamic performance and can be almost useless when external magnetic field interference influences the sensor.
These issues can be partially corrected by the introduction of a low cost motion sensor to the heading algorithm. The motion sensor performs badly over the long term but has higher accuracy in the short term. This allows the data to be mixed in a Kalman filter in order to provide improved performance. The results are impressive, although not in the same class as our optical technology.
The magnetic heading option on MiniSense2 is of particular interest for the owners of small ROV systems where magnetic anomalies often hinder performance. The outlay needed even for CDL's TOGS low cost FOG systems can be undesirable on smaller ROVs, so the MiniSense2 with aided magnetic heading provides a navigation option at a far lower price point.
The MiniSense2 is also a full inertial platform, capable of running almost all the algorithms CDL have developed for our TOGS technology. This means that placing a MiniSense2 system on a small electric ROV system will provide features in the future that are only now being fitted to work class vehicles. Positioning technology such as USBL aiding and mid water station keeping (albeit at lower accuracies) will soon be a reality at a price level previously unheard of.
With the additional recent introduction of 'static mode', a special algorithm for use in high accuracy level sensing applications, the MiniSense2 is now easily the most flexible low cost motion sensor in the subsea market.