2016 IEEE Aerospace Conference最新文献

{"title":"The impact of NASA's small business innovation research program on invention and innovation","authors":"Aleksandar Giga, R. Terrile, A. Belz, F. Zapatero","doi":"10.1109/AERO.2016.7500927","DOIUrl":"https://doi.org/10.1109/AERO.2016.7500927","url":null,"abstract":"We empirically determine the impact of the NASA Small Business innovation Research (SBIR) Program on invention and innovation. The NASA SBIR program selects a portfolio of technology proposals, submitted by small businesses to an annual solicitation. Funding may be awarded in two tranches, a 6-month phase I award and a subsequent, 2-year phase II award. Over the last decade, the total annual awarded funding was about $100-140M with Phase I awards growing from $100-125K and phase II awards from $500-750K. Typically, about 15-20% of submitted Phase I proposals are awarded and only these awards are eligible to submit a phase II proposal. The success rate at phase II is about 40%. We looked at NASA SBIR data between 1999 and 2006 to determine the impact of receiving a phase II award on invention and innovation by using patent activity as a proxy. Data from all NASA Mission Directorates and over a range of years were considered and combined into a statistically significant collection. We examined the phase II proposed technologies and the subsequent patent history of the submitting companies in the five years after the award cycle. We find that phase II awarded companies had a significantly greater number of awarded and cited patents, over this time frame, than companies not awarded an SBIR phase II. Specifically, we find an overall increase in awarded patents of 39% for SBIR awarded companies versus non-awarded companies. This difference is statistically significant at the 95% confidence level. We also examined subsets for these data to quantify the effects of company size and previous patent awards on these trends.","PeriodicalId":150162,"journal":{"name":"2016 IEEE Aerospace Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129312247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A unified method for solving the frequency plan of space-borne software-defined radios","authors":"Erika A. Sanchez, N. Adams","doi":"10.1109/AERO.2016.7500638","DOIUrl":"https://doi.org/10.1109/AERO.2016.7500638","url":null,"abstract":"Software-defined radios (SDR) give space missions great flexibility by supporting diverse waveforms and mission scenarios. To configure and control this range of capability requires a model of the processing elements, both analog and digital. In this work we describe a unified method for solving and implementing the receiver and exciter frequency plans for a wide variety of hardware architectures. The flexibility of an SDRs frequency plan is enabled with programmable synthesizers and oscillators (e.g. DDS). Careful arrangement of these elements and band-selection filters is central to the hardware design. In the hardware design, up conversion and down conversion stages characterize the frequency plan for receive and transmit chains. Individual up conversion and down conversion stages can be segmented into a set of series or parallel blocks that completely represent the hardware design. Each stage can be fully characterized using a generalized converter block. We then formulate the frequency plan as a set of linear equations and solve the frequency plan with a single matrix operation. The converter stages also manage constraints on bandwidth and preferentially chose parameters to minimize spurious output. A block can also represent a reference oscillator or tunable DDS as part of a feedback control loop. The unified method can also accommodate a shared local oscillator between the receive and transmit paths. The end user can specify desired receive and transmit frequencies, and the method solves for all internal LO frequencies, or vice versa. The frequency plan solution is implemented in software and can be applied on any SDR platform. A notional configuration of the Frontier Radio for NASA's Europa mission is used as an example to demonstrate the methods.","PeriodicalId":150162,"journal":{"name":"2016 IEEE Aerospace Conference","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129312662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Technology development of automated rendezvous and docking/capture sensors and docking mechanism for the Asteroid Redirect crewed mission","authors":"Heather Hinkel, M. Strube, J. Zipay, S. Cryan","doi":"10.1109/AERO.2016.7500637","DOIUrl":"https://doi.org/10.1109/AERO.2016.7500637","url":null,"abstract":"This paper will describe the technology development efforts NASA has underway for Automated Rendezvous and Docking/Capture (AR&D/C) sensors and a docking mechanism and the challenges involved. The paper will additionally address how these technologies will be extended to other missions requiring AR&D/C whether robotic or manned. NASA needs AR&D/C sensors for both the robotic and crewed segments of the Asteroid Redirect Mission (ARM). NASA recently conducted a commonality assessment of the concept of operations for the robotic Asteroid Redirect Vehicle (ARV) and the crewed mission segment using the Orion spacecraft. The commonality assessment also considered several future exploration and science missions requiring an AR&D/C capability. Missions considered were asteroid sample return, satellite servicing, and planetary entry, descent, and landing. This assessment determined that a common sensor suite consisting of one or more visible wavelength cameras, a three-dimensional LIDAR along with long-wavelength infrared cameras for robustness and situational awareness could be used on each mission to eliminate the cost of multiple sensor developments and qualifications. By choosing sensor parameters at build-time instead of at design-time and, without having to requalify flight hardware, a specific mission can design overlapping bearing, range, relative attitude, and position measurement availability to suit their mission requirements with minimal non-recurring engineering costs. The resulting common sensor specification provides the union of all performance requirements for each mission and represents an improvement over the current systems used for AR&D/C today. These sensor specifications are tightly coupled to the docking system capabilities and requirements for final docking conditions. The paper will describe NASA's efforts to develop a standard docking system for use across NASA human spaceflight missions to multiple destinations. It will describe the current design status and the considerations and technologies involved in developing this docking mechanism.","PeriodicalId":150162,"journal":{"name":"2016 IEEE Aerospace Conference","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124696761","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Highly compliant active clinging mechanism","authors":"Walter Saravia, B. Udrea","doi":"10.1109/AERO.2016.7500742","DOIUrl":"https://doi.org/10.1109/AERO.2016.7500742","url":null,"abstract":"A mechanism is currently designed and analyzed with the goal of providing controlled adhesion to objects with surfaces with little known surface finish, of varying curvature, and different materials. The main purpose of the mechanism is that of ensuring a soft docking, controlled in closed loop, for attachment to large pieces of orbital debris. Other envisaged purposes for the mechanism are sample collection and manipulation in free fall or at small bodies and in-situ analysis of cohesive forces in regolith. The electroadhesion forces are generated by the electric fields and polarization present when applying a voltage gradient across the adhesion mechanism. The current design consists of Pyralux®composite clad material on which macro fiber composites (MFCs) are attached. Once the proof of concept of the actuation with MFCs is completed, sensors will be added in order to provide capabilities for proprioception. The copper side of the Pyralux®layer is chemically etched in order to form an electrostatic adhesion device (EAD). Three EAD electrode configurations were investigated by analyzing, fabricating, and testing. Two configurations have the shape of multiple interlocking fine combs and one configuration has multiple spiral electrodes arranged similarly to the suckers of a cephalopod limb. The three designs were tested in order to compare the shear adhesion forces created. The interlocking comb or spiral pairs are envisaged to be individually actuated to control the force of adhesion during the clinging process. A MFC is embedded to the exposed non-adhering side of the Pyralux®composite so that the curvature of the mechanism can be controlled prior and post-contact with the object of interest. Strain gages are to be interspersed with the MFCs to determine the local curvature and possibly the curvature rate of the mechanism during clinging. The mechanism will have two feedback control loops one that controls the EAD electrodes and thus the clinging force and the other for the EAP patches which controls the curvature of the mechanism. It is planned that the loops are operated inside the attitude determination and control loop of the nanosatellite that docks with the piece of orbital debris or retrieves a sample from the surface of a small body. Out of the three pad designs investigated, the spiral design resulted in highest adhesion forces when adhering to a conductive and also an insulator surface. Tests were also completed comparing the adhesion force generated when activating the MFC to the adhesion without it's use. Results indicate an increase in adhesion when actuating the MFC on a surface with curvature.","PeriodicalId":150162,"journal":{"name":"2016 IEEE Aerospace Conference","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129537188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A study of adaptive coding and modulation over free space optical link using OCTL data","authors":"Jay L. Gao","doi":"10.1109/AERO.2016.7500885","DOIUrl":"https://doi.org/10.1109/AERO.2016.7500885","url":null,"abstract":"In this paper we utilized the downlink channel data captured at the Optical Communication Test Laboratory (OCTL) in support of the Lunar Laser Communications Demonstration (LLCD) to evaluate the potential performance gain of using adaptive coding and modulation (ACM) scheme to increase data volume while mitigating weather impairment. The study assumed that the estimated signal and noise photon counts statistics generated by concurrent processing of the downlink signal is available in real time to drive a closed-loop control of the code rate and the PPM order of the downlink. Downlink data from two representative passes were used. Pass no. 12, which occurred on October 29, 2013 and lasted 24 minutes and 15 second, recorded several link outages due to thin cloud and cloud interruption and is used to calibrate the symbol error constraint for the adaptive modulation algorithm. Pass no. 20, which was 19 minutes and 16 seconds long and occurred on November 18, 2013, operated over very clear sky and large sun-earth-probe (SEP) angle (approx. 170 degrees) and provided a representative sample of a clean optical channel. This study ignores constraints such as peak and average power limitations and processing overhead. Impacts of delay in the control loop are not addressed in this study, therefore any performance enhancement indicated by this study is only applicable to a short propagation delay environment. For deep space environment, further analysis will be required to determine the benefit of ACM.","PeriodicalId":150162,"journal":{"name":"2016 IEEE Aerospace Conference","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129640016","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A spherical co-ordinate space parameterisation for orbit estimation","authors":"Jose Franco, E. Delande, C. Frueh, J. Houssineau, Daniel E. Clark","doi":"10.1109/AERO.2016.7500573","DOIUrl":"https://doi.org/10.1109/AERO.2016.7500573","url":null,"abstract":"An interesting challenge in orbital estimation problems for space surveillance using optical sensors is that, since both the orbital mechanics and the sensor observation process are non-linear, the standard filtering solutions such as Kalman filters are inapplicable and lead to divergent results. Naïve particle filtering solutions also fail since they require many particles to accurately represent the posterior distribution. However, since the sensor observation noise is modelled as a multivariate Gaussian distribution, it may be expected that the same single-object probability distributions, once projected into the augmented sensor space (a full spherical frame centred on the sensor), assume a simpler form that can be approximated by a multivariate Gaussian distribution. In this paper, a sequential Monte Carlo filter is proposed for the orbital object estimation problem, which exploits the structure of the measurement likelihood probability by introducing a proposal distribution based on a linear Kalman filter update.","PeriodicalId":150162,"journal":{"name":"2016 IEEE Aerospace Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129798715","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Power requirements for Rayleigh beacon generation in laser beam projection systems","authors":"A. Sergeyev","doi":"10.1109/AERO.2016.7500500","DOIUrl":"https://doi.org/10.1109/AERO.2016.7500500","url":null,"abstract":"The task of delivering sufficient level of airborne laser energy to ground based targets is of high interest. To overcome the degradation in beam quality induced by atmospheric turbulence, it is necessary to measure and compensate for the phase distortions in the wavefront. Since, in general, there will not be a cooperative beacon present, an artificial laser beacon is used for this purpose. In many cases of practical interest, beacons created by scattering light from a surface in the scene are anisoplanatic, and as a result provide poor beam compensation results when conventional adaptive optics systems are used. Three approaches for beacon creation in a down-looking scenario have been developed and commonly used in simulating laser beam projection systems utilizing down-looking scenarios. In the first approach, the entire volume of the atmosphere between transmitter and the target is probed by scattering an initially focused beam from the surface of the target. The second approach utilizes generation of an uncompensated Rayleigh beacon at some intermediate distance between the transmitter and the target and allows compensation for only part of the atmospheric path. Lastly, a more advanced technique of bootstrap beacon generation that allows achieving dynamic wavefront compensation creating a series of compensated beacons along the optical path, with the goal of providing a physically smaller beacon at the target plane. For all case sceneries discussed above, it is crucial to estimate the power requirements for single Rayleigh beacon generation as a function of the distance from the transmitting laser source. Sufficient amount of energy is required to allow for wavefront sensor measurements with satisfactory signal-to-noise ratio. In this paper, the calculations conducted in order to estimate the power requirements for a single Rayleigh beacon as a function of the laser altitude and the slant range between the transmitter and the generated beacon are presented. To fully understand the results presented here, some physical understanding of nature of scattering is required. There are four main types of scattering the transmitting light can experience: Rayleigh, Raman, Mie, and resonance scattering. Raman scattering is very weak typically, only one photon out of 107 is Raman scattered. Resonance scattering requires tuning the laser to the frequency closely comparable to the internal rotational or vibrational frequency present in the specific atom or molecule. Presence of dust, fog, haze, or clouds cause the Mie scattering and may vary unpredictably. In practice, it is important to produce a stable and constant intensity beacon, and therefore the generation of a Reileigh beacon for laser beam projection systems should not rely on surrounding atomic and molecular content, and unpredictable events such as presence of clouds, haze, dust or fog. Therefore, to properly estimate power requirements for Rayleigh beacon generation it is reasonably to only re","PeriodicalId":150162,"journal":{"name":"2016 IEEE Aerospace Conference","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130533133","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design of decoupled tracking filter with platform motion compensation for airborne surveillance radar","authors":"A. Rathi, R. Narasimhan, D. Seshagiri, E. R. Prashanthi, Vivek Krishna, N. Prasad","doi":"10.1109/AERO.2016.7500923","DOIUrl":"https://doi.org/10.1109/AERO.2016.7500923","url":null,"abstract":"This paper discusses about the design of tracking filter for airborne multifunction active phased array long range radars. The radar under consideration has surveillance as primary function, where “track-while-scan (TWS) mode” of tracking is performed. In addition to surveillance, the radar has to perform closed loop tracking on priority targets of interest. Long range surveillance radars generally are designed to have narrow azimuth beam and wide elevation beam to obtain required height coverage with single bar. The measurement accuracies in elevation axis would be generally 10 times poorer compared to azimuth axis. This poses a problem to tracking system which uses Cartesian co-ordinates for modeling target kinematics. The higher error in any one of measurement dimension gets coupled to the other measurement axes resulting in inaccurate tracking. In tracking literature various decoupled tracking schemes are proposed to avoid the coupling of errors. This approach produces the desired results if there is no measurement transformations involved between different coordinate systems which leads to coupling of measurement axes. For the airborne target tracking system, co-ordinate transformations between different frames of reference is unavoidable. Own platform movement (translational and rotational) has to be fully compensated for optimal tracking filter. This necessitates use of 3D transformations resulting in coupling of errors between measurement axes. Hence decoupling the tracker design which would yield favorable results as suggested earlier does not provide relief in this case. The elevation measurement being not so accurate owing to broad beam, its coupling with other radar measurements during transformations disturbs the tracking accuracies leading to track deviations and inaccurate beam positioning for target under dedicated mode of tracking. Further, in search on move ground based radars, due to the multipath phenomena the elevation measurement sometimes depicts larger inaccuracies leading to inaccurate tracking. This paper proposes a scheme to address the tracking problems for both the above cases with weak coupling between axes at the output of transformation. The performance proposed method is compared with standard filter relying on coupled coordinate transformation for platform motion compensation (PMC). The results show that the proposed technique greatly mitigates the problem of widely different inaccuracies of radar measurements yet enabling compensation of own platform motion for all six degrees of freedom.","PeriodicalId":150162,"journal":{"name":"2016 IEEE Aerospace Conference","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126896770","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the maneuvers operational response for NASA's soil moisture active-passive (SMAP) mission","authors":"J. Tirona","doi":"10.1109/AERO.2016.7500510","DOIUrl":"https://doi.org/10.1109/AERO.2016.7500510","url":null,"abstract":"The Soil-Moisture Active-Passive (SMAP) spacecraft requires various kinds of in-orbit maneuvers over the course of its three-year mission. The types of maneuvers include preplanned commissioning maneuvers to reach its science orbit, regularly executed orbit maintenance maneuvers to overcome drag and other nominally occurring phenomena, as well as (the possibility of) collision avoidance maneuvers. The architecture of the spacecraft - in terms of availability of commanding via ground assets, the inherited avionics' ability to sequence and execute commands, and the capability of available subsystems able to carry out maneuvers - was well defined early in the development of the spacecraft and mission, well before the operational plan for responding to maneuver requests was cemented. [2] The systems engineering challenge became: how to accommodate all three types of maneuvers in the confines of this well-defined architecture. This paper will describe how the operations team on SMAP successfully met this challenge. Specifically, it will dive into the three pronged approach that SMAP developed to handle each type of maneuver described above - to meet the timeliness requirements leveraged on the operations team to execute said maneuvers, while continuing to fit within the allotted staffing profile during nominal operations. Defining this paradigm to fit the mission's architecture meant re-defining the original paradigm, (planned maneuvers being thought of separately than collision avoidance maneuvers), and re-classifying all responses to maneuver requests as variations and permutations of a singular operational response to a maneuver request. This paper will also describe the tools that were created to simplify the human interface and automate as much of the response as was possible. Finally, this paper will describe, at a very high level, some of the problems encountered and lessons learned by the operations team when this process was executed the first four times during the first ninety days of operations. Though the architecture of the operations team's response to maneuver requests will never be repeated exactly, the flexibility that was inserted via redefining the scope of the problem and by redefining the human interfaces should influence future projects' architectures earlier in their development - in the hopes that said influence will save time and money in the future.","PeriodicalId":150162,"journal":{"name":"2016 IEEE Aerospace Conference","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129070880","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recreating planar free-floating environment via model-free force-feedback control","authors":"N. Muraleedharan, D. R. Isenberg, Iacopo Gentilini","doi":"10.1109/AERO.2016.7500612","DOIUrl":"https://doi.org/10.1109/AERO.2016.7500612","url":null,"abstract":"Force-feedback control can be used to recreate a free-floating environment to test Space Robots (SRs). An SR is mounted on a force and torque sensor attached to the end effector of a Robotic Platform (RP), which is controlled to nullify the measured forces and torques. This eliminates external forces acting on the SR through the mount, hence conserving linear and angular momentum of the SR when no external forces are present. The advantage of the proposed method with respect to previous approaches is that free-floating conditions are recreated without any knowledge of the SR's equations of motion, as the only inputs to the controller are the forces and torques measured by the transducer at the mount. The force-feedback control method can also handle external forces such as those arising from contact disturbances and the thrusters without having any SR control input knowledge since the forces and torques that are generated transfer through the spacecraft body into the sensor at the mount. Simulation results collected using the proposed new strategy are compared against previously used free-floating environment recreation methods such as position and orientation tracking control of simultaneous hardware-in-the-loop (HIL) simulation. On average, the comparison between trajectories shows a position RMS error reduction of over 90% and an orientation RMS error reduction of over 96%.","PeriodicalId":150162,"journal":{"name":"2016 IEEE Aerospace Conference","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116511517","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}