Helmholtz Association

Work Package 2200 – Infrastructures for Navigation and Communication

In work package 2200, the overall navigation and communication architecture shall be investigated and realized in hardware. The goal is to find an adequate solution on systems level to provide robotic vehicles with sufficient information about their position in an unknown environment and to establish a communication infrastructure for operator surveillance, data transfer and remote controlled operations. This work package needs close cooperation with other work packages as their demands determine the requirements on positioning precision, data-transfer bandwidth, availability and reliability.

Communication
State of the art of communication in planetary exploration is still mostly satellite based. In this case a higher infrastructure, represented by an orbiting satellite, is needed to have the capability to work as a communication relay. The communication methods used for deep-sea activities are mostly wire- or ultrasonic based. The higher infrastructure on the water surface is represented by ships and buoys which are used as communication relays for satellite communication.

Within this alliance general communication architecture shall be designed that is based on a hybrid solution. This means some main communication modules have the capability to communicate with the higher infrastructure to provide a high bandwidth data exchange and command transfer. In addition to that, the communication on the planetary surface or ocean bed shall be provided by small communication modules and some repeaters for range extension. Their performance, size, band width and communication range could vary, depending on their individual range of use. This is mandatory to find a practicable solution for the individual requirements and capabilities of the communication module.

The communication architecture shall be independent from its surrounding media. This goal can be reached by a modular approach. Thus, depending on the environment, the end effectors can be changed whilst the software, electronics hardware and protocol layers can be kept the same with some small modifications on the lowest level. Different potential end effector technologies for data transfer, like optical- or radio wave based concepts, shall be compared in respect to their performance in the respective environment.

Navigation
To realize autonomous operations and the very challenging task of a remote operated base build-up, navigation is a bottleneck for operations and planning of any activity. Thus, the on-site navigation is second in priority for establishing a complex infrastructure in an unknown environment.

Precise landing capabilities are essential for multi-lander science missions and infrastructure build-up at extraterrestrial bodies and deep-sea areas. The more precise a lander can bring its load to its destination target, the less energy is needed for transportation. A landing guidance system is required that can be allocated aboard the lander or placed on the planetary surface around the landing area to provide the incoming landers with precise data about its position during descent. There are several positioning systems in use and under investigation. In the deep sea, the most common technology is the measurement of acoustical logging. The reflection of acoustic signals from underwater surfaces is monitored by microphones. With the use of multiple microphones, a 3D picture of the underwater surfaces, including the position of submarine instrument, can be created. Alternatively the use of the Doppler-effect could provide information about the position and driving direction of a moving vehicle.