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The Thermal InfraRed Sensor (TIRS), an infrared (IR) radiometer developed at Centro de Astrobiología, is one the sensors that compose the Mars Environmental Dynamics Analyzer (MEDA) onboard NASA's Mars 2020 mission. It will measure the net thermal infrared radiation, reflected solar radiation at the surface, atmosphere temperature and surface skin brightness temperature using five different channels...
A microwave frequency interferometer sensor has been demonstrated to have the sensitivity and accuracy needed to characterize fluid stream clouds comprising both water and ice crystals for applications in wind tunnel testing. Considerations for in-flight sensing and measurement are suggested.
The calibration of air-data systems for the evaluation of the flow angles is based on the availability of high-accuracy reference measurements of angle-of-attack and angle-of-sideslip. Typically, these are obtained by auxiliary sensors directly providing the reference angles (e.g. nose-boom vanes) or by analytically reconstructing them using calibrated airspeed measurements and inertial data. With...
Thermogravimetry (TG) or Thermogravimetric Analysis (TGA) is a widely used technique to obtain information about thermal stability and composition and to monitor different thermal processes of materials. The TGA analysis is frequently used to monitor the deposition/sublimation and absorption/desorption processes of volatiles compounds in different environments: outgassing rates from degassing in space...
The paper discusses the possibility of locating four spacecraft in four out of the five Lagrange points of the Sun-Earth system and exchanging electromagnetic pulses among them. Including stations on Earth, various closed paths for the pulses are possible. Time of flight measurements would be performed. The time of flight difference between right- and left-handed circuits is proportional to the angular...
Based on the formalism of General Relativity, we analyze generalizations of concepts used in conventional geodesy. One such concept is the Earth's geoid. We present our definition of the relativistic geoid in terms of the level sets of a time-independent redshift potential. Such a potential exists for any congruence of Killing observers, i.e. for any rigidly moving object associated with a stationary...
White light interferometry, also known as low-coherence interferometry, is a mature technique used in metrology to measure 3D surface morphology at sub-micrometric scale. This technique is used in many fields of applications, such as optical qualification tests, surface metrology, medicine and others. We present here a new set-up able to measure the distance of an object with sub-micrometric accuracy...
The LARASE research program is funded by the Italian National Institute for Nuclear Physics and it is a collaboration between different institutions. LARASE aims to provide very precise and accurate measurements of the General Relativity effects that perturb, from the Newtonian point of view, the trajectory of a satellite orbiting the Earth. The improvements obtained by the LARASE collaboration with...
This paper describes several approaches for the calibration of translational and rotational alignment errors between a camera and a set of laser illuminators for a position determination system. Detailed algorithms are derived and covariance of calibration residuals in both error state and target position determination accuracy are obtained. An example with system design parameters is given to demonstrate...
We have designed and tested a thrust stand conceived for the characterization of RF plasma thrusters. The balance has been employed in the development of small-medium size HPT prototypes, therefore it allows for an high number of tests per day with an accuracy within the 10%. The balance relies on the counterbalanced-type pendulum concept, which allows to achieve high sensitivity while maintaining...
Stereo visual odometry is one of the most accurate dead-reckoning methods for estimating the motion of a moving vehicle but it strongly depends on a robust matching of the image features in the stereo frame. If a stereo camera is observing the environment from a critically small distance the two field of view can be subjected to poor or absent overlapping. That leads to failure of the computation...
Pressure distribution measurement over the surface of an aircraft can contribute to drag reduction on the flight, increasing aerodynamic efficiency and decreasing fuel consumption. Current methods for pressure distribution measurement include the use of Pressure Sensitive Paints (PSPs), which can only be used during the design phase, and Fiber Bragg Grating (FBG), which is not easy to install on existing...
This paper presents an experimental activity carried out to evaluate the performance of LIDAR-based algorithms for pose determination of uncooperative space targets. The test setup includes a scanning LIDAR and a monocular camera mounted with a fixed relative geometry, providing 3D (point cloud) and 2D (image) representations of the same scene within the shared portion of their respective Field-of-Views...
This paper, the first of three, compares the merits of current or planned missions to Jupiter and Europa and then proposes a lander vehicle for studying Europa. It outlines the launch vehicle and spacecraft, the mission trajectory, and potential spacecraft instruments. It estimates power consumption, cost, and schedule for a mission to Europa.
This paper, the second of three, proposes a suite of instruments for a lander vehicle for studying Europa. It outlines the science and engineering parameters for the instruments. It estimates the mass, volume, and power consumption for each instrument.
This paper, the third of three, proposes a configuration for a lander vehicle for studying Europa. It outlines the network and power distribution for the instruments. It proposes burying the electronics in ice to shield them from radiation. It proposes a method for assembling the spacecraft in an autoclave to provide planetary protection, as well as, flying the boosters and sky crane away from Europa...
The development of novel superconducting photon detectors requires the investigation of non-traditional materials to exploit their specific properties and realize novel/enhanced devices. Nd2−xCexCuO4±5 is a moderate high transition temperature cuprate superconductor exhibiting n-type conduction which properties can be changed by modifying its cerium and oxygen content. Ultra-thin films of this compound...
This article describes a new approach in characterizing amplifiers and other two-port devices. Traditionally, key performance parameters such as gain or AM/AM and AM/PM distortion are characterized using a CW stimulus. However, most devices are operated with modulated signals instead of CW in real life. These key characteristics typically vary greatly between CW and modulated operation.
Strapdown Inertial Navigation System play an important role in many different kinds of applications. As the accuracy of which is deeply influenced by the sensors precision, so the system error propagation should be addressed. Based on the airborne vehicle characteristics, a method based on neural network is proposed to estimate the attitude, velocity and position error of system. The simulation experiment...
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