Projects:2017s2-292 Wide-Area Sun Sensor

Introduction

We have for many millennia been fascinated with any realms beyond our reach; humanity has long held a curiosity surrounding those places which for so long seemed to be impossible to explore. However, within the most recent millennium and particularly the past handful of centuries, the space above us intrigued some of us so strongly that our will and desire to explore further the upper levels of our troposphere, then the stratosphere, the mesosphere and so on drove us to incredible breakthroughs. At the height of the Cold War in the mid-1950s, arguably the most critical developments were occurring. The United States of America and the former Soviet Union were competing for control of space due to its perceived strategic importance, rivalling the role of air superiority during World War II. Ultimately, the Soviets were victorious in what would be termed the Space Race with their satellite Sputnik I in 1957. The real race, to further explore space however, was only just beginning.

To this day, we are continuing to explore the upper limits of Earth's atmosphere (and beyond), to better understand the properties of space. many thousands of satellites have been launched by more than 40 countries [1] since Sputnik I. A general trend across many technologies is the optimisation of size, weight, cost and power features with the passage of decades, and satellites have been no different. Space exploration has to this end even become affordable and achievable for many academic institutions worldwide.

Abstract

Project 2017s2-292 seeks to explore the design and fabrication of a wide-area sun sensor for implementation aboard a cube satellite for the purposes of attitude or orientation sensing with respect to the sun whilst in orbit. Some initial loose constraints that have been set out by the client include size, weight and power (SWaP) dimensions in the order of 10mm x 20mm x 8mm for the whole device to ensure it does not significantly hinder launch or orbit mechanics. Also set out by the SWaP constraints is that the sensor must operate on a 3.3V supply, and consume power no greater than values in the order of tens of mW, to ensure there is adequate power available to the satellite's other systems. Additionally, a field-of-view (FoV) requirement of 120°, or ±60° from the sensor's geometric centroid, has been expressed. This will in turn limit the physical and optical geometry of the sensor, and its aperture.