Pyrotechnic systems (i.e. initiators, transmission lines, time delays, rod cutters...) are key elements for space launch vehicles as they fulfill critical functions like engine starting, booster separation and distancing, spacecraft releasing etc. Existing pyrotechnic devices are reliable and robust but also heavy, quite large and complex. Furthermore, their installation is relatively costly due to their hazardous characteristics. Importantly, they also have to ensure high reliability level requirements. In this context, the LAAS-CNRS in collaboration with the French Space Agency (CNES) and Dassault-Aviation has proposed a new technological solution suitable for next generation launchers in replacement of classical pyrotechnic devices. It is based on smart and safe PyroMEMS interconnected and communicating via digital bus. This work relies on the knowledge of LAAS-CNRS in nano energetics and micro technology integration, and on Dassault-Aviation skills in pyrotechnics engineering. The work of this PhD thesis consists in the design and fabrication of safe and smart pyrotechnic initiator able to communicate on a digital bus and also to charge up electrical energy. This initiator is compatible with terminal functions using the European Standard Initiator (ESI). It includes energy storage, mechanical arming system, electrical protection circuitry, and also a micro controller that drives the different elements and communicates with the bus. The innovation of this works lies in the on-chip integration (ASIC) of several functions like energy management, electric safeties, mechanical arming management, and communication. Mechanical arming is based on a micro brushless motor allowing a safe and arm device smaller than 0,5cm3. Electro-pyrotechnic conversion is realized by micro-chip initiators integrating multilayer nano-thermite. The energetic material is initiated by Joule effect in a metallic filament insulated from the substrate by a polymeric membrane (SU-8). The MEMS fabrication uses standard and collective micro-electronic processes that allow the fabrication of 1000 micro-chips on a 4 inch wafer. Thanks to these innovations, we fabricated an Integrated Functions Initiator demonstrator, smaller than 3cm3 and we experimentally validated the device good functioning.
