Qualification and Flight of a Cutting Edge Sunsensor for Constellation Applications

Satellites for a constellation can be build in a significantly more cost-effective way because the Non-recurring Engineering charges (NRE) can be spread over multiple units. A further significant cost reduction can be achieved if the units and subsystems are optimized for volume production and the units are produced in a continuous production line with a sustainable throughput. Though this optimized production can lead to significant improvement in cost effectiveness, this should in no way impair the reliability of the products. It can be reasoned that the approach implemented by Lens R&D will even increase the reliability of production as it allows for statistical process monitor and control of the product quality. As reliability and cost effectiveness in volume production are core to the Return On Investment (ROI) for constellation owners, these properties have been core design drivers for the BiSon Sunsensors discussed in this paper. After a design change that led to the development of an automated assembly robot, the cutting edge BiSon64-ET and BiSon64-ET-B Sunsensors developed by Lens R&D went through a full ESA qualification program. This means that for the first time ever, a Sunsensor optimized for volume manufacturing has finished a full ESA qualification program. A flight contract has been signed to fly 20 sensors on the two ESA science satellites making up the Proba-3mission. Flight data however already will be received earlier, through a precursor 3U Cubesat mission, flown through the Dutch company Innovative Solutions In Space (ISIS). This paper focusses on the novel manufacturing approach used, the qualification performed and the processes needed to cost effectively produce large quantities of Sunsensors for constellation applications

The time for SCOTS has come

With all major European primes starting to work on programs \u3e100 satellites in 2015 the time for Space grade Commercial Off The Shelf components has come. For many years there have been discussions on costs savings by offering COTS components and especially the cubesat community knows several vendors that offer space systems in a COTS fashion. None of these component however qualify for the extreme requirements posed by the current constellations under design as most of them have to operate above 1000 km and are preferred to have a 10 to 15 year lifetime. This leads to several megarads of total dose en 15 years at 1400 km will require the ability to withstand some 65.000 thermal cycles. In order to fulfil these requirements full space grade true high reliability components will be needed where on the other hand the financial constraints are very strong. This is bound to lead to a completely new generation of real high reliability Space grade Commercial Off The Shelf (SCOTS) components. Without knowing these constellations would come, Lens R&D has been focussing on recurring production of true high reliability sensors and now has several sensors in final stage of optimisation which will be offered in a SCOTS approach. The presentation will focus on the mega constellation market, the issues faced when developing SCOTS components and current state of development of our BiSon series of sunsensors