Sergio Fernandez Romero

The purpose of this paper is to describe the specific magnetic measurements that must be made on the flight model ANSER (Advanced Nanosatellites Systems for Earth observation Research) satellite to ensure the necessary magnetic cleanliness, to characterize the magnetic torques, and to verify the magnetometer measurements. The objective is to develop the necessary technology to implement future space missions based on Satellite Constellations. This article describes both the innovative measurement procedures used and the measurement uncertainty calculations. The results obtained from both Cube Sats and the most important magnetic elements are presented, including the determination of the remaining and induced magnetic moment of spacecraft, and the calibration or characterization of magnetometers and magnetic torquers.

Volcanoes are typical features of the solar system that offer a window into the interior of planets. Thus, their study can improve the understanding of the interiors and evolution of planets. On Earth, volcanoes are monitored by multiple sensors during their dormant and active phases. Presently, this is not feasible for other planets’ volcanoes. However, robotic vehicles and the recent technological demonstration of Ingenuity on Mars open up the possibility of using the powerful and non-destructive geophysical tool of magnetic surveys at different heights, for the investigation of surfaces and subsurfaces. We propose a methodology with a view to extract information from planetary volcanoes in the short and medium term, which comprises an analysis of the morphology using images, magnetic field surveys at different heights, in situ measurements of magnetic susceptibility, and simplified models for the interpretation of geological structures. This methodology is applied successfully to the study of different examples of the main volcanic zones of the Iberian Peninsula, representative of the Martian intraplate volcanism and similar to Venus domes, as a preparatory action prior to the exploration of the rocky planets’ surfaces.

Novel materials, as multi-ply carbon fiber composites (CFC), are increasingly used in the industry due to their outstanding mechanical properties in relation to their weight. In this regard, from the standpoint of electromagnetic compatibility (EMC), shielding effectiveness (SE) is a key parameter that often determines the scope for application of a given material. This article addresses the application of two complementary standards, ASTM D4935 and IEC 61000-4-21, to the SE measurement of different CFC test samples with more than 10 layers and a very large expected shielding. The analysis of the limitations encountered and the description of applied improvements on the traditional measurement procedures on each method are also included, showing promising results. On the other hand, there are alternative methods to evaluate the SE of CFC based on their DC square resistance. Consequently, and forthe shake of completeness, a novel setup for high precision measurement of the DC square resistance of CFC samples is also described along the article.

Geomagnetic prospection is an efficient and environmentally friendly geophysical method for the analysis of the magnetic minerals’ distribution in the subsurface. High-resolution measurements require on-ground campaigns. However, these activities might imply high costs, risk and time consumption. Some more recent works have started to use magnetometers on-board remote piloted aircrafts. Normally, they fly at a constant altitude and use scalar probes. This configuration permits the determination of the magnitude of the magnetic field but not the direction, and requires advanced techniques for in-depth interpretation of the sources. In this manuscript, we describe the accommodation of a system for vector magnetometry in a drone whose flight altitude follows the elevation of the terrain. This singularity improves the capability of interpretation, including constraints in dating due to the record of the geomagnetic field. The work consists of the design, development and implementation of a solidary payload system anchored to the body of the platform in order to determine the vector magnetic field. It describes the details of the system and the performance characteristics obtained after the calibration, as well as its demonstration via a field campaign in the spatter deposits of Cerro Gordo volcano in Campos de Calatrava volcanic province in Spain.

This letter addresses on the design of a planetary protection shell for performing the Electro-Magnetic Compatibility (EMC) tests of the Anisotropic Magneto-Resistance (AMR) sensor of the ExoMars mission. This mission has strict bio-burden requirements. The ElectroMagnetic (EM) properties of several materials have been investigated for measuring their transmission coefficients and the novelty of this letter is the use of Fused Deposition Modeling (FDM) technology as the production method. Additive manufacturing is presented as a promising technology in the field of radiofrequency since it can use a wide range of materials (including thermoplastics) with high and low transmission coefficient. The investigation comprises the analysis of the electromagnetic properties of several 3D printer materials in order to study their transmission coefficients. Seeing the EM characterization results, it was decided to produce a shell using FDM technology because it provides control over the grounding of the instrument and makes easier the integration, cleaning and protection against impacts during the operation, with great versatility and low cost. To finish, the shell has been proved during the acceptance EMC tests of the flight model and flight spare AMR instrument.

This paper explains the research process carried out for the development and manufacture of the planetary protection cover for carrying out the electromagnetic compatibility (EMC) tests of the an-isotropic magneto-resistance (AMR) sensor of the ExoMars 2020 mission. This mission has strict bioburden requirements. The electromagnetic properties of several materials have been analyzed in order to study their transmission coefficient and the innovation of this project is the use of fused deposition modeling (FDM) technology as manufacturing method. Additive manufacturing is presented as a promising technology in the field of radiofrequency since it can use a wide range of polymeric materials (thermoplastics) with low transmission coefficient. Observing the electromagnetic (EM) characterization results, it was decided to manufacture a protective cover using FDM technology, because it allows control over the grounding of the instrument and facilitates the integration, cleaning and protection against impacts during the manipulation, with great versatility and low cost. Finally, the cover has been verified during the acceptance EMC tests of the flight model AMR instrument.

Modern aircraft employ profusely carbon fiber composites (CFC) for their construction. Then, it is mandatory to characterize the behaviour of this kind of materials for its use under harsh electromagnetic environments. In that sense, this paper presents the application of two standards, the ASTM D4935 and the IEC 61000-4-21, to the measurement of the shielding effectiveness (SE) of aeronautical multi-ply CFC laminates frequently used for the construction of aircraft. Each technique is well suited for a specific material or realization and a specific frequency range. So, both techniques are complementary and should be developed in parallel. Taking into account the high SE expected for this kind materials, the set-ups imply the measurement of very low signals, that poses an experimental challenge that has to be faced. Then, in this study, different test samples and realizations of CFC materials have been fabricated and measured. Improvements on the traditional measurement procedures have been applied, obtaining promising results.

In this study, measurements inside the fuselage of an unmanned air vehicle (UAV) are conducted using a novel double-loaded loop probe. The characterization and evaluation of electromagnetic interference (EMI) within VAVs is a main research topic and requires state-of-the-art measurement methodologies. The developed probe is capable of obtaining accurate measurements as commercial reference E-Field broadband probes, introducing new advantages based on the reduction of the probe's electronics and the availability of the full time-domain data. Allowing to compute simultaneously the electric and the magnetic field and to measure high-amplitude electromagnetic pulses. The laser-probe works together with multi-channel full-time domain system computing the electromagnetic fields using an oscilloscope. Regarding the double-loaded loop probe characterization and validation, it has been carried out by comparing the results with different validation methods, like Feature Selective Validation Method and the Integrated Error against Logarithmic Frequency.

Open area test sites (OATS) have been traditionally employed for aircraft electromagnetic compatibility certification tests because of the large size of these items. In this regard, unmanned aerial vehicles (UAVs) have emerged in the last years and, albeit being sometimes notably smaller, yet they have to accomplish for the same certification process. This paper investigates into the possibility of using a reverberation chamber for performing two aircraft low-level coupling tests, namely, low-level direct drive and low-level swept fields, and compares the results with those obtained in an OATS, in both cases using a representative part of a UAV.