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Downlink scheduling methods that minimize either contact time or data latency are described. For deep-space missions these two methods yield very different schedules. Optimal scheduling algorithms are straightforward for ideal mission scenarios. In practice, additional schedule requirements preclude a tractable optimal algorithm. In lieu of an optimal solution, an iterative sub-optimal algorithm is...
This paper describes an integrated system for the real time acquisition, streaming, and display of stereoscopic 3D video in mixed reality environments. These mixed reality environments combine real-time stereoscopic video with rendered 3D environments composed of sampled and modeled 3D data from actual landscapes or structures. While live video itself is an important part of exploration, reconnaissance,...
STUDSAT - 2 is a Student Satellite Program carried out by the undergraduate students from seven engineering colleges from the state of Karnataka, India. STUDSAT-2 is India's First Twin Satellite Mission which aims to demonstrate Inter-Satellite Communication and improving temporal resolution by taking images of the same part of the earth by the Twin Satellites. STUDSAT-2 consists of two Nano Satellites...
This paper highlights the methodology and effectiveness of adapting the reconfigurable SpaceCube system to solve complex application requirements for a variety of space flight missions. SpaceCube is a reconfigurable, modular, compact, multi-processing platform for space flight applications demanding extreme processing power. The SpaceCube system is suitable for most mission applications, particularly...
In order to reduce the knowledge gap associated with long-duration human exploration of Mars, a manned precursor mission destined for one of the Martian moons is currently considered a feasible option for testing and demonstrating critical technologies within the Martian system. The 2013 Caltech Space Challenge, a student mission design competition held at the California Institute of Technology, addressed...
Extravehicular Activity (EVA) is a highly demanding activity during space missions. The current NASA spacesuit, the Extravehicular Mobility Unit (EMU), might be thought of as the ‘world's smallest spacecraft’ and is quite an engineering achievement. However, the EMU has also led to discomfort and musculoskeletal injuries, mainly due to the lack of mobility in the pressurized suit that makes moving...
Hybrid cloud is defined as a cloud infrastructure composed of two or more cloud infrastructures (private, public, and community clouds) that remain unique entities, but are bound together via technologies and approaches for the purposes of application and data portability. This paper will review a novel approach for implementing a secure hybrid cloud.
We propose to utilize a previously developed, deployed, and clinically tested comprehensive visual field test and diagnosis system to investigate the relationship between intracranial pressure (ICP) and intraocular pressure (IOP) elevations that occur during long-term space travel and visual field loss. Recent data describing this phenomenon, now called the Visual Impairment/Intracranial Pressure...
The ability to accurately observe the Earth's carbon cycles from space gives scientists an important tool to analyze climate change. Current space-borne Integrated-Path Differential Absorption (IPDA) lidar concepts have the potential to meet this need. They are mainly based on the pulsed time-of-flight principle, in which two high energy pulses of different wavelengths interrogate the atmosphere for...
This paper introduces a ranging algorithm for wireless sensor networks. Here, a novel time slot based technique is applied for ranging of sensor nodes within the clustered sensor network. The proposed technique avoids clock synchronization of sensor nodes by exploiting the round-trip time-of-flight measurements. Moreover, it is energy efficient as it avoids the complexity inherent in multi-user detection...
Multiple-input multiple-output radar systems have shown great potential for better performance in detection and angular resolution and measurement accuracy. However, the implementation of a MIMO radar can create significant costs due to the ability to generate orthogonal waveforms on each transmit element. Furthermore, the design of waveforms that meet the necessary linear independence for all elements...
Long duration missions present numerous risks to crew health and performance. The international space community is actively studying these effects and possible mitigation techniques, but much work remains to be done. As such the space community and space agencies are increasingly cooperating to enable timely answers in support of exploration mission needs. Crew health and performance are critical...
In this paper we address the problem of tracking several moving targets with a sensor whose location and orientation are uncertain. This is a generalization of the well-known problem of feature-based simultaneous localization and mapping (SLAM). It is also a generalization of multitarget tracking (MTT) in general, and related to sensor bias estimation. We address such problems from the perspective...
The detection and tracking of orbiting space debris is vital for spacecraft safety and satellite longevity. The United States Air Force Space Surveillance System (AFSSS) uses a continuous wave (CW), multiplestatic site radar system designed to detect, catalog, & track objects orbiting over the continental United States. Object position data collected by the AFSSS stations is categorized by the...
The Space Shuttle was launched 135 times and nearly half of those launches required 2 or more launch attempts. The Space Shuttle launch countdown historical data of 255 launch attempts provides a wealth of data that is important to analyze for strictly historical purposes as well as for use in predicting future launch vehicle launch countdown performance. This paper provides a statistical analysis...
The present paper describes parametric studies conducted to define the Uranus entry trade space. Two different arrival opportunities in 2029 and 2043, corresponding to launches in 2021 and 2034, respectively, are considered in the present study. These two launch windows factor in the 84-year orbital period, significant axial tilt, and the wide ring system of Uranus. As part of this study, an improved...
The objective of this paper is twofold; to present findings from a recent literature survey on distributed decision and control, also known as consensus theory; and to postulate future research directions, given a new avenue of interest generated as a result of the investigation and a brief consensus simulation. While the literature survey focuses on this topic, the spectrum of challenges in the field...
The Van Allen Probes mission which was designed and built by the Johns Hopkins University, Applied Physics Laboratory (APL) is also being operated by the APL mission operations team in Laurel, Maryland. The two Van Allen Probes spacecraft have been successfully collecting data on orbit since they were launched on August 30, 2012. These twin probes are providing unprecedented insight into the physical...
The Autonomous Ascent and Descent Powered-Flight Testbed (ADAPT) is a closed-loop, free-flying testbed for demonstrating descent and landing technologies of next-generation planetary landers. The free-flying vehicle is the Masten Space Systems Xombie vertical-takeoff, vertical-landing suborbital rocket. A specific technology ADAPT is demonstrating in the near-term is Guidance for Fuel-Optimal Large...
The end-to-end verification of a spacecraft photovoltaic power generation system requires light! A low-cost, portable, and end-to-end photovoltaic-system test appropriate for NASA's new generation of Class D missions is presented. High risk, low-cost, and quick-turn satellites rarely have the resources to execute the traditional approaches from higher-class (A-C) missions. The Class D approach, as...
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