The Reconfigurable Robust Routing for Mobile Outreach Network (R3MOON) provides advanced communications networking technologies suitable for the lunar surface environment and applications. The R3MOON technology is based on a detailed concept of operations tailored for lunar surface networks, and includes intelligent routing algorithms and wireless mesh network implementation on AGNC’s Coremicro Robots.

The product’s features include an integrated communication solution incorporating energy efficiency and disruption-tolerance in a mobile ad hoc network, and a real-time control module to provide researchers and engineers a convenient tool for reconfiguration, investigation, and management.

A new routing protocol extends existing routing methods such that more alternate routes can be found between the source and the destination. This leads to better packet delivery rate as well as larger extent of delivery. Alternate routes can also be used for route optimization wherein the most energy efficient route is chosen. The criterion of energy efficiency can be readily reconfigured to accommodate different design objectives and network requirements.

When disruption occurs, a data buffering mechanism is established so that the undeliverable packet is stored at a dynamically selected storage node while awaiting redelivery. Since the undeliverable packet is not discarded but buffered, robustness is achieved. A proper storage node is chosen by considering its buffer space, battery power, and location.

A hardware prototype network is developed based on AGNC’s product solutions such as Coremicro Robot and Coremicro 40 GIS. The multi-robot demonstration scheme incorporates mesh and relay networking. With three network nodes, routing capability is tested, verified, and monitored on this platform with a real-time Coremicro 40 GIS based robot Operator Control Unit (OCU). Multimedia data is exchanged in the network through effective communication and routing, even upon disruption. When one of the direct links is disrupted, an alternative two-hop path can be used to accomplish the communication.

R3MOON offers the following novel features in a complete and comprehensive communication solution:

  • Energy-efficient routing achieved through path selection. This approach is highly feasible and implementable.
  • Disruption-tolerant routing achieved through data buffering and retransmission mechanism. This approach is also based on AODV (ad hoc on-demand distance vector) routing protocol. Retransmission from the storage node achieves more graceful packet discarding rate, faster restoration, and higher redelivery rate than retransmission from the source node.
  • Implementation and performance demonstration through software and hardware realization. The simulation shows animation for the route discovery process, and validates the performance of the proposed method in various simulated network settings.
  • An actual implementation of a mesh network architecture that integrates network control and optimization functionalities. The integral approach combines communication, navigation, control, and other functions needed to perform the mission. Each network node (e.g., robot) houses modules such as robot control processor, sensor fusion processor, and image processor, which are all interconnected through a communication module. The communication module connects all the nodes in the network. The configuration can be customized for designer’s needs such as reduction of power consumption or simplification of wiring. In the higher level of the R3MOON architecture, a human/machine interface is embedded for executing AGNC’s 4D-GIS and for monitoring and management of the network.
  • A communication module that can be configured with different routing algorithms to run the mesh network. Both proactive [e.g., OLSR (Optimized Link State Routing)] and reactive (e.g., AODV) based routing protocols can be used in the module. A mesh wireless network with optimized routing algorithms enhances system reliability and performance.

This work was done by Ching-Fang Lin of American GNC Corp. for Glenn Research Center. For more information, download the Technical Support Package (free white paper) at www.techbriefs.com/tsp under the Electronics/Computers category.

Inquiries concerning rights for the commercial use of this invention should be addressed to NASA Glenn Research Center, Innovative Partnerships Office, Attn: Steve Fedor, Mail Stop 4–8, 21000 Brookpark Road, Cleveland, Ohio 44135. Refer to LEW-18501-1.

NASA Tech Briefs Magazine

This article first appeared in the August, 2010 issue of NASA Tech Briefs Magazine.

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