Structural study of a wind sensor for Mars under vibrations induced during launch

Abstract

Arid, rocky, cold and ’apparently’ lifeless, Mars has captured humanity’s attention for the past few decades. "It’s such a fundamental question. ’Are we alone?’ " Hubbard said. Scientists are deeply interested in the Red Planet since it was found plenty of evidence that it was once far warmer and could potentially host life as we know it. NASA’s Mars Exploration Program has built up momentum, from the first flybys, followed by orbiters, then landers and rovers to a sample-return mission. Mars is seen as a prime target for future human colonization but, before sending any astronaut to the Red Planet, more knowledge is required. The characterization of surface weather in Mars is one of the main science objectives in NASA’s Mars Exploration Program, specially, the measurement of wind direction, as it is considered to be the dominant force shaping the Red Planet’s landscape. Currently, UPC is improving a 3D miniaturised wind sensor capable of collecting data samples of Mars’ atmospheric dynamics. The purpose of this paper is to do a structural study of the UPC’s wind sensor for Mars under vibrations induced during the launching phase. In order to do so, the sensor has been evaluated under a quasi-static test, a random vibration test and a pyroshock test. The first chapter will include detailed explanation of the state of the art. This section defines the characteristics of the three spatial certification tests performed to the sensor including different Finite Element Model satellite simulations already carried out by different research groups. In the second chapter, a detailed description of the wind sensor is elaborated. Then, it has been defined the mathematical formulation behind the different test using Reissner-Mindlin flat shell theory, a Vibrations analysis and a Shock analysis. The fourth chapter details the geometry, element type and boundary conditions used to perform each of the tests. Next, the different results have been analysed and finally some conclusions have been drawn.