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Functionality
Moving Lander - This designation stands for a vehicle that can move autonomously on the ocean floor employing a wheel or a caterpillar traction system. The aim is a targeted, scientific investigation of the ocean bottom of the deep sea - a region which is widely unknown!
The concept of the vehicle builds up on experiences with similar
scientific tools. The so called LANDER - stable platforms that
equipped with according sensors are deployed on the ocean
floor and by dropping a weight return the surface - are considered
as standard tools of deep sea research. They allow for measurements
of biogeochemical processes in water depth down to 6000 m. The
sensors and sampling instruments that are used on theses systems
will also be installed on the Moving Lander.
The Aberdeen University Large Abyssal Fall Fall Vehicle (LAFF 1)
Even Know-how from space science is used within the project. Similar to planetary missions the landing and target region is not well known. Although only sparse information is available it has to be assured that certain scientific tasks can be accomplished. Therefore concepts taken for instance from successful developments of Moon or Mars vehicles can very helpful and will be implemented.
The well known Mars vehicle SPIRIT has been equipped with different measuring and sampling instruments. This multidisciplinary approach will be pursued for the Moving Lander system as well.
The Mars vehicle SPIRIT
Main specifications of the Moving Lander
| Maximum depth | 6000 m |
| Deployment duration | Up to 9 months |
| Operation range | 1 km |
| Max. number of sampling positions | 30 |
| Weight in air | 1,5 t |
| Weight in water | 100 kg |
| Typical dimensions | 3 x 2 x 2 m |
Propulsion
For the selection of the propulsion system energy efficiency, adaptability on different surface conditions, steering capability and reliability are of utmost importance. Wheel as well as caterpillar propulsion will be considered and both will be evaluated regarding their suitability
Control & communication
The vehicle will be equipped with a central control unit that will allow conducting certain tasks at a predefined scheme free from disturbance. This includes the control of the movement of the vehicle and the control of the function of the measuring probes. Within the final phase of the project the vehicle can be interrogated via a satellite and an acoustic link to ask for housekeeping data and an excerpt of scientific data collected.
CAN-Busbasierte Steuerungsmodul für den Radantrieb.
Windowsbasierte Benutzeroberfläche zur Steuerung des Fahrzeug und der wissenschaftlichen Instrumente
Navigation
The navigation module allows for the systematic investigation of a certain region. That includes the revisit of a measuring site. It is planned to reach a position accuracy of 1m.
Energy
A strong restriction of the application possibilities results from the limited energy supply of the vehicle. Beside the propulsion the energy demand of the entire control system and the measuring instruments for durations of 6-9 months has to be covered. With current existing battery technologies certain restrictions exist regarding the number of measuring positions, the operating range and the deployment time. The energy amount that can be integrated into the vehicle would suffice to power a 100 W light bulb for 5 days.
Within the development phase new battery systems like the ones that are currently being used for mobile phones will be evaluated regarding their suitability for deep sea applications.
Sensors
A basic suite of sensors will be integrated into the vehicle to cover the scientific demands. This includes salinity, temperature, turbidity and current measurements. Additional to that incubation chambers will be integrated into the vehicle that allow for investigating biogeochemical processes as for instance determining metabolic rates.
By employing a modular concept additional other systems can be easily integrated.
Buoyancy
The vehicle is designed such that it has a weight of typically 100 kg in water and after dropping a ballast weight it will return to the surface. To reach this target weight spezial buoyancy materials like glas spheres or syntactic foam has to be employed. The material itself should have low dead weight which means that the density has to be low. Within this area manufacturers recently came up with new concepts, that will be used within the final version of the Moving Lander vehicle.
Syntactic foam - Glas spheres are embedded in casting resin