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Up to now, the reliability achieved by COTS components was largely sufficient for avionics, in terms of failure rate as well as time to failure. With the implementation of new and more integrated technologies (90 nm node, 65 nm and below), the question has arisen of the impact of the new technologies on reliability. It has been stated that the lifetime of these new technologies might decrease. The drift is expected to be technology dependent: integration, technology node, materials, elementary structure choices and process pay a key role. Figures have been published, which gives smaller lifetime than the 30 years generally required for avionics. This would of course impact not only the reliability, but also the maintenance of COTS-based avionics. Hence a new policy should be defined for the whole COTS supply chain. Faced with these impending risks, different methodologies have been developed [1], [2].

ChemCam is one of the 10 instrument suites on the Mars Science Laboratory, a martian rover being built by Jet Propulsion Laboratory, for the next NASA mission to Mars (MSL 2009). ChemCam is an instrument package consisting of two remote sensing instruments: a Laser-Induced Breakdown Spectrometer (LIBS) and a Remote Micro-Imager (RMI). LIBS provides elemental compositions of rocks and soils, while the RMI places the LIBS analyses in their geomorphologic context. Both instruments rely on an autofocus capability to precisely focus on the chosen target, located at distances from the rover comprised between 1 and 9 m for LIBS, and 2 m and infinity for RMI. ChemCam will help determine which samples, within the vicinity of the MSL rover, are of sufficient interest to use the contact and in-situ instruments for further characterization.

In the short term, traditional thermal control techniques, currently reaching their potential limit, will no longer meet the challenge imposed by the natural evolution in electronic packaging, characterized by an ever-increasing level of integration and power. In this context, new architectures must be developed, with thermal control based on high performance heat transfer devices. The Integration of Miniature Heat Pipe (MHP) seems to be one of the most effective and promising solutions for the future. This paper summarizes the work, performed within the frame of a partnership with the CNES, aiming at contributing to develop and evaluate this technology. Beyond theoretical and technological studies, we have manufactured or supplied several miniature heat pipe devices (MHPD) to constitute the elementary thermal control blocks, corresponding to the main packaging hierarchical levels (components, boards, equipment) of future generation of space vocation electronic units.

The INTERnational Gamma-Ray Astrophysics Laboratory (INTEGRAL) is an ESA observatory scientific satellite which was successfully launched on the 17th of October 2002. The payload consists in four instruments : an optical camera (OMC), a X-ray monitor (XRM), an imager (IBIS) and a spectrometer (SPI). The spectrometer (20 keV-8 MeV energy range, 2.3 m high, 1.1 m diameter, around 1300 kg) has been supplied by CNES where this instrument has been managed, assembled and tested before delivery to ESA for satellite level activities. This paper describes the spectrometer flight model thermal design achieved thanks to the different international partners, gives and overview of the cryostat used to cool down the detection plane and exposes the thermal validation plan used at instrument level (thermal mathematical model and thermal test philosophy, cryostat thermal validation). We then focus on in-flight performances and compare them to expected ones.

The Netlander mission aims to deploying on the surface of Mars a network of 4 landers, which will perform simultaneously measurements in order to study the internal structure of Mars, its sub-surface and its atmosphere. This paper describes the phase B thermal control concept of the Netlander Surface Module, taking into account various thermal environments from the cruise to Mars phase until the landing and the one Martian year phase on the Mars surface. The paper focuses on two specific thermal tests. The first one is a thermal conductivity measurement of three pre-selected insulation materials in a 6 - 10 hPa CO2 environment, and the second one is a performance test of a Loop Heat Pipe designed to comply the Netlander Surface Module needs. This paper is mainly derived from the report referenced ref. 1.

This paper describes the thermal balance test which has been performed on the spectrometer SPI Structural and Thermal Model (INTEGRAL project) from August 27th to September 17th 1999. Main SPI modes have been simulated in order to qualify the instrument thermal control. MLI efficiency has been measured, as well as thermal conductance to the payload module (PLM). For this, a specific thermal adaptator (a mechanical frame and two aluminum plates regulated by two cryostats) has been developed and will also be used for thermal vacuum tests of the SPI Flight Model. This thermal adaptator and its behavior during thermal balance test are described.