For space missions which land on other celestial bodies, modernizing and especially miniaturizing the navigation subsystem is an important objective. Saving mass by miniaturizing elements of spacecraft either allows more mass for the payload or reduces the mass of the spacecraft and thereby saves fuel and launch costs.
The SINPLEX (Small Integrated Navigation system for PLanetary EXploration) relative navigation system answers this need. The main goal of the SINPLEX project was to develop an innovative navigation system with a mass which is significantly lower than conventional systems for exploration missions which include a landing and/or a rendezvous and capture/docking phase. Reducing mass while maintaining good navigation performance is achieved by functionally integrating different sensors, utilizing micro- and nanotechnologies to miniaturize electronics and combining sensor measurements using sensor hybridization approaches to improve the performance of the complete navigation subsystem.
Within the project, a breadboard system was produced, which includes an inertial measurement unit (IMU), a star tracker (STR), a navigation camera, a laser altimeter/range finder (LA), a navigation computer (NC) and a power distribution unit. The system was designed to meet the combined requirements needed for a general Moon landing, asteroid landing and sample container rendezvous/capture mission scenario. Hardware-in-the-loop (HIL) testing was done at DLR’s TRON (Testbed for Robotic Optical Navigation) facility to measure its navigation performance and demonstrate its applicability for relative autonomous navigation in space applications.
More information about the SINPLEX project can be found at the project website: http://www.sinplex.eu. SINPLEX is a research and development project funded by the European Commission under the 7th Framework Programme (grant ID 284433).