Maritime (Autonomous) Vehicle (MAV)
Technology
A Maritime Autonomous Vehicle (MAV) may have an operational area on the sea (Unmanned Surface Vehicle, USV) or subsea (Unmanned Autonomous Vehicle, AUV).
In both cases the vehicle is battery powered and needs functions for battery management and power management. The duration of the mission will depend on the capabilities for minimizing unnecessary use of power. This requires both smart power management and a good low power electronics design.
A vehicle needs thrust and attitude control. Buoyancy and gravity forces can be used as thrust for AUVs. Foils generating lift forces can minimize the drag for USVs and control the depth for AUVs. Foils and rudders can also control the pitching for AUVs and roll and yaw for both AUVs and USVs.
Motion control of MAVs requires motion sensing with the best possible low-cost solution for high precision motion sensing. High precision motion sensing also requires high precision and self-calibrating functions. Ocean currents varying through the water column will make the vehicle drift away from the pre-programmed track. This must be handled by the vehicle motion controller.
Acoustic modems can be used for both data distribution and ranging for AUVs. It could also be possible to implement a mesh network for AUVs. A mesh network can also be useful for USVs using long-range and low power wireless connections. USVs can also measure and distribute their own position using GNSS receivers.
All the functions required for implementing a MAV, should first be implemented as a simulated vehicle. The simulated backbone of the vehicle will be a dual CAN network for redundant one-to-many communication. It should be possible to connect NMEA devices to this network.
Building a vehicle
The simulated vehicle will be built before the hardware is engineered. This will make it possible to handle integration issues between the components before it is built.
The components in a MAV are more encapsulated than components in a MASS. An error occurring while building a MAV cannot easily be undone. By using a digital simulated MAV, the digital components can be tested before assembly. Unnecessary hardware issues can then be avoided.
Servicing a vehicle
USV and AUV don’t require so much approval today as they mainly are used in time limited operations and can be serviced between operations. This may change if the possibility of servicing is reduced as the operations become autonomous.
Operating a vehicle
A vehicle can also be operated using the same type of operational interface as a Maritime Autonomous Surface Ship (MASS). This re-usability will also make it easier to integrate the operation of both MASS and MAV in a remote-control center. An operation including a MASS and a MAV can also more easily be done in the same system.
Re-building a vehicle
MAV components can be added, edited or removed in different versions. Tools in the ioStudio framework will make it possible to handle re-building of simulated digital vehicles in a structured way. MAVs may be built in larger numbers. Version control will then be even more important.