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In the last decades a number of failures in which a solar cell is short-circuited to the panel substrate have been reported or suspected. In the meantime protective measures, like single string connection and use of bleed resistors in the grounding circuit have been implemented. However it is still not always clear whether such an anomaly occurred and the in-flight instrumentation is usually not sufficient to provide unambiguous evidence. This paper describes a simple way to identify both the occurrence of such a cell to substrate short circuit and the panel on which it is located. The paper is then completed with the main results from the CNES study performed in 2012 to demonstrate the performance, analyse the reliability and assess the industrial feasibility of such a system.

Flexible solar array architecture is proposed instead of rigid one, for high power solar array used from space tug mission to GEO satellite one, but also for specific scientific mission. THALES ALENIA SPACE has developed with Centre National d’Etudes Spatiales (CNES) support, innovative mechanical flexible solar array architecture, using 22 m long carbon tape-springs. The first part of the study was to design, predict, verify carbon tape-springs mechanical behaviour during deployment and coiling phases at room temperature. THALES ALENIA SPACE built mechanical flexible solar array mock-up full scale width / half scale length and performed deployment and rolling-up tests. The second part was to design, predict carbon tape-springs mechanical behaviour with large temperature range due to solar array missions. THALES ALENIA SPACE used again flexible solar array mock-up, performed deployment/coiling tests with innovative tape springs. This 11th ESPC paper describes results of these development activities and the THALES ALENIA SPACE forecast on this flexible solar array market.

We studied the holding power during cut-out tests of 4 different screw fixation devices of the femoral head, correlated to head size and bone density, on 48 paired deep frozen proximal femurs of fresh gross specimens. We found no significant effect of the device on the holding power. There was a significantly higher maximal load at failure in large and dense heads. It seems then unnecessary to advocate more sophisticated but also more expensive devices to fix femoral neck fractures.

In order to make accurate measurements, sun simulators used for solar cell characterisation need to be calibrated with standard solar cells. These so-called secondary working standards are derived from primary reference cells and are used for every cell measurement. To generate primary reference cells, balloon calibration campaigns are a good compromise between accuracy, flight opportunity and cost. CNES calibrates primary standards with stratospheric balloon flights since 1976. Safety rules limited the flight opportunities, so it was not possible to propose the calibration service since 2005. A new balloon facility is developed in CNES with the help of ESA in order to calibrate space solar cells with high accuracy. The first flight is planned in April 2017 in Alice Springs, Australia.