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Aiazzi, Carolina

Publications and source records attributed to Aiazzi, Carolina.

IRIS: High-fidelity Perception Sensor Modeling for Closed-Loop Planetary Simulations

Perception plays a key role in autonomous and semi-autonomous planetary exploration vehicles. For instance, landers can use computer vision techniques for identifying safe landing locations, aerial vehicles use cameras as navigation sensors, and planetary rovers use them for localization and hazard detection. Engineering simulations of such systems requires the accurate modeling of perception and vision sensors for simulating autonomy scenarios. In addition, the modeling of sensors for landers, aerial and ground vehicles requires the ability to handle large and high-resolution terrains, the accurate modeling of illumination, hi-fidelity rendering via ray/path tracing and the inclusion of sensor characteristics. Vision sensor models strive to simulate sensor reality by using physics principles to model the interaction of light and objects. Furthermore, high frame rate performance is highly desirable for in-the-loop simulations involving vehicle dynamics and control software. In this paper we describe a new sensor modeling capability called Inter-planetary Rendering for Imaging and Sensors (IRIS) that meets these requirements for the real-time and high-fidelity simulation of vision sensors for planetary aerospace and robotics applications.

Elmquist, Asher

Prototype Development of a Variable Altitude Venus Aerobot

This paper presents the design methodology and results from the first subscale prototype jointly developed by JPL and Near Space Corporation for a variable altitude Venus aerobot. This vehicle is based on the principle of a two-part balloon for which pumping helium gas between the balloons can modulate buoyancy and thereby control the altitude of the vehicle. The intended mission application at Venus is a cloud-level exploration across an altitude range of 52 to 62 kilometers for weeks or months, circumnavigating the planet multiple times and carrying an approximately 100 kg payload module containing all scientific instruments, avionics and other vehicle support systems. The first prototype is approximately one-third scale (4 m diameter) and serves as a proof-of-concept test article allowing for evaluation of manufacturing approaches and laboratory testing to evaluate performance. Two key design features of the prototype as built are the use of Teflon film on the outside of the balloon to protect it from the sulfuric acid aerosols in the Venusian atmosphere and second surface metallization of that film to reflect most incident sunlight and thereby limit diurnal temperature and the associated temperature-driven pressure fluctuations. This prototyping effort has been complemented with a detailed vehicle simulation activity that incorporates the relevant balloon physics and thereby models the expected dynamic behavior of the aerobot in both the Earth and Venus atmospheres. Data obtained in laboratory tests of the prototype have been used to validate, verify and update that simulation model as described in the paper.

Turner, Caleb