Analyzing the Performance of a Miniature 3D Wind Sensor for Mars

Abstract

This paper analyzes the behavior of a miniature 3D wind sensor designed for Mars atmosphere. The sensor is a spherical structure of 10 mm diameter divided in four sectors. By setting all the sectors to constant temperature, above that of the air, the 3D wind velocity vector can be measured. Two sets of experiments have been performed. First, an experimental campaign made under typical Mars conditions at the Aarhus Wind Tunnel Simulator is presented. The results demonstrate that both wind speed and angle can be efficiently measured, using a simple inverse algorithm. The effect of sudden wind changes is also analyzed and fast response times in the range of 0.7 s are obtained. The second set of experiments is focused on analyzing the performance of the sensor under extreme Martian wind conditions, reaching and going beyond the Dust Devil scale. To this purpose, both high-fidelity numerical simulations of fluid dynamics and heat transfer and experiments with the sensor have been performed. The results of the experiments, made for winds in the Reynolds number 1000–2000 range, which represent 65–130 m/s of wind speed under typical Mars conditions, further confirm the simulation predictions and show that it will be possible to successfully measure wind speed and direction even under these extreme regimes.

Venus Life Finder Habitability Mission: Motivation, Science Objectives, and Instrumentation

“…This instrument is suited to cover temperature measurements from 80 km to 20 km and pressure measurements from 70 km to 20 km, thereby encompassing the entire cloud deck and stagnant haze layer below the clouds. An example anemometer is a miniaturized 3D wind sensor being developed for the Martian atmosphere [46]. The WIS instruments are extremely lightweight with a total mass of less than 100 g and require total power of less than 1 W. All the WIS sensors are exposed to the atmosphere for direct measurements.…”

Spherical probe for the thermophysical characterization of regoliths for planetary exploration using frequency methods

“…The core Pt resistors can be used to measure temperature and inject power at the center of the sphere. This capability is particularly important if using the structure as a wind sensor, [10,11]. In this case, the same current magnitude is applied in the cores as in the sectors.…”

“…Recently a 3D heat flux sensor has been proposed for thermal property determinations for regoliths [9]. The sensor is based on the spherical structure of a Mars wind sensor [10,11]. The objective of this study is to analyse the capability of this 3D heat flux sensor to additionally characterize the thermophysical properties of the regolith (thermal conductivity and diffusivity).…”