Current space applications are pushing for improved on-board processing abilities, in terms of higher computing power, flexibility and fault-resistance, in order to keep up with the huge amount of collected scientific data. Multiprocessor systems seem a viable solution to match these requisites. In particular, systems employing Multistage Interconnection Networks (MINs) offer the advantage of an effective resource allocation, depending on variable workloads and occurrence of faults. The paper presents a fault-tolerant interconnection mechanism, based on redundant MIN, for multi-sensor systems. The proposed system is implemented by means of Field Programmable Gate Arrays (FPGAs) and allows a flexible re-organization of computing resources in dependence of varying operating conditions. Fault-tolerance is achieved both by exploiting the MIN intrinsic redundancy and by using an efficient FPGA re-configuration technique.