Information Exploitation and Planning for a Sensor Web

Multidisciplinary Knowledge Aspects of Reliable Software and Systems Engineering

Avionics Processing Evolution—Apollo to Constellation

Overview of the PredGuid Skip Entry Guidance Algorithm

Protection of Sensors for Biological Applications by Photoinitiated Chemical Vapor Deposition (piCVD) of Hydrogel Thin Films

ISS Contingency Attitude Control Recovery Method for Loss of Automatic Thruster Control

Space Station Zero Propellant Maneuver Flight Results Compared to Eigenaxis

Zero-Propellant Maneuver Concept and Flight Results

Micro RF Tags for Medical Imaging

Amino Alcohol-Based Elastomeric Poly(ester amide)s for Hepatic Tissue Engineering

Enhancement of In Vitro Capillary Tube Formation with Synthetic Nanotopography

Aging Behavior of Master Bond EP29LPSP as Determined by Thermal Analysis

Micromechanical Device for Intracochlear Drug Delivery

Micromachined Surface Stress Sensor with Electronic Readout

Real-time Landing Point Redesignation (LPR) Algorithm

Numerical Modeling, Microfabrication, and Cell Adhesion Testing of a Tissue Engineered Loop of Henle Device

Long Endurance UUVs for Precursor ASW Search and Barrier Operations

Linear Covariance Analysis Techniques Applied to Orion Cislunar Operations

Optical Nanosensors for Intracellular Sodium Analysis

Autonomous Landing and Hazard Avoidance Technology

Human Interactive Landing Point Redesignation for Lunar Landing

Expedition MCM-D Layout for Multilayer Die

Indoor Geolocation Using RF Multipath with Probabilistic Data Association

Orion GN&C Architecture for Increased Spacecraft Automation and Autonomy Capabilities

Machine-Aided Design of an Air-Launched Missile Defense System

High-Throughput Nanohole Array-Based System to Monitor Multiple Binding Events in Real Time

Heavy-Ion and Total Ionizing Dose (TID) Performance of a 1-Mbit Magnetoresistive Random Access Memory (MRAM)

Target Geolocation from a Small Unmanned Aircraft System

Biodegradable and Biocompatible Gecko-Inspired Tissue Adhesive

Performance Evaluation of Stem Cell Multiresolution Texture Analysis

Vacuum-Sealed MEMS Package with an Optical Window

Estimate of Burn Error for Open-Loop Guidance Maneuvers During Proximity Operations

Managing Energy and Mode Transitions in Orion Skip Entry Guidance

Performance of an Automated Feature Tracking Lunar Navigation System

Unmanned System Risk Management

Self-Contained Method for Safe and Precise Lunar Landing

Automated Frozen Sample Aliquotting System

A Method for Die Thickness Reduction to sub-35 µm

Search for New Physics with the BEACON Mission

Concept and Computational Design for a Bioartificial Nephron-on-a-Chip

Autonomous Mid-Course Navigation for Lunar Return

Relative Navigation for the Orion Vehicle

Abramson, M.R.; Carr, F.R.; Carter, D.W.; Kolitz, S.E.; Leake, B.E.; Markuzon, N.; Scheidler, P.J.

Information Exploitation and Planning for a Sensor Web

8th Earth Science Technology Conference (ESTC), Adelphi, MD, 6/24/2008-6/26/2008. Sponsored by: NASA's Earth-Sun Systems Technology Office (ESTO) (Draper Report no. P-4702)

Abstract: We present progress made in developing capabilities that fit within the Earth Phenomena Observing System (EPOS) sensor web dynamic replanning architecture described in our NSTC 2007 paper. We first describe a sensor web use case that is one of the drivers in our development. We then discuss two major information exploitation capabilities, the first focused on cloud cover forecasts and the second focused on wild fire prediction. We also describe several planning capabilities, including system-of-system coordination, planning for multiple heterogeneous unmanned aerial vehicles (UAVs) and manned aircraft, and enhanced single satellite planning capabilities, focused on EO-I. We describe the evolution of these capabilities toward compliance with Open Geospatial Consortium (OGC) standards.

Subjects: SENSOR WEBS, GEOGRAPHIC INFORMATION SYSTEMS, CAPABILITIES

Antelman, E.T.

Multidisciplinary Knowledge Aspects of Reliable Software and Systems Engineering

27th Annual International Space Development Conference, Washington, D.C., 5/29/2008-6/1/2008. Sponsored by: National Space Society (Draper Report no. P-4710)

Abstract: Can we build a sustainable community of systems and people on the Moon? This is not a technology development problem. This is an understanding, integration, and design problem! The solution will require large numbers of people in both public and private organizations to collaboratively learn, challenge, and build a cooperating community of systems that create a knowledge base and technical platform for humans to sustain life off Earth. When we succeed, there will be a roadmap to approaching the big problems that will improve life and the environment on Earth also.

Subjects: KNOWLEDGE MANAGEMENT, MULTIDISCIPLINARY ANALYSIS, SYSTEMS ENGINEERING, PROBLEM SOLVING

Aucoin, M.A.

Avionics Processing Evolution—Apollo to Constellation

27th Annual International Space Development Conference, Washington, D.C. 5/29/2008-6/1/2008. Sponsored by: National Space Society (Draper Report no. P-4709)

Abstract: Apollo Guidance Computer relied on a highly dependable single-string system with extensive ground testing followed by full-scale uncrewed and then crewed flight testing.

Subjects: APOLLO GUIDANCE COMPUTER (AGC), AVIONICS, EVOLUTION (DEVELOPMENT)

Barton, G.H.; Hattis, P.D.; Neave, M.D.; Putnam, Z.R.

Overview of the PredGuid Skip Entry Guidance Algorithm

Aerospace Control and Guidance Systems Committee Meeting, Salt Lake City, UT, 3/5/2008-3/7/2008. Sponsored by: SAE (Draper Report no. P-4656)

Subjects: ENTRY GUIDANCE, ALGORITHMS, CREW EXPLORATION VEHICLES (CEV), CREW MODULE (CM)1

Baxamusa, S.H.; Montero, L.; Dubach, J.M.; Clark, H.A.; Borros, S.; Gleason, K.K.

Protection of Sensors for Biological Applications by Photoinitiated Chemical Vapor Deposition (piCVD) of Hydrogel Thin Films

Biomacromolecules, Vol. 9, No. 10, 10/2008, pp. 2857-2862 (Draper Report no. P-4712-REV-1)

Abstract: We report photoinitiated chemical vapor deposition (piCVD), a gentle synthetic method for the preparation of ultrathin films (~100 nm) of the hydrogel poly(hydroxyethyl methacrylate) (pHEMA). piCVD occurs near room temperature and requires only mild vacuum conditions. The deposited films swell rapidly and reversibly in buffer solution, and the swelling properties can be controlled via the deposition conditions. Analysis of the swelling data indicates that the mesh size of the hydrogel creates a selectively permeable coating. The mesh is large enough to allow small molecule analytes to permeate the film, but small enough to prevent the transport of large biomolecules such as proteins. X-ray photoelectron spectroscopy (XPS) shows that the films decrease nonspecific adhesion of the protein albumin by nearly 8-fold over bare silicon. A dry process, piCVD is suitable for coating particles with diameters as small as 5 µm. The absence of solvents and plasmas in piCVD allows films to be directly synthesized on optode sensors without degradation of sensitivity or response time.

Subjects: BIOSENSORS, FILMS, CHEMICAL VAPOR DEPOSITION (CVD)

Bedrossian, N.S.; Bhatt, S.A.; Alaniz, A.; McCants, E.W.; Nguyen, L.; Chamitoff, G.E.

ISS Contingency Attitude Control Recovery Method for Loss of Automatic Thruster Control

31st Guidance and Control Conference, Breckenridge, CO, 2/1/2008-2/6/2008. Sponsored by: AAS (Draper Report no. P-4632)

Abstract: In this paper, the attitude control issues associated with International Space Station (ISS) loss of automatic thruster control capability are discussed and methods for attitude control recovery are presented. This scenario was experienced recently during Shuttle mission STS-117 and ISS Stage 13A in June 2007 when the Russian guidance, navigation and control (GN&C) computers, which command the ISS thrusters, failed. Without automatic propulsive attitude control, the ISS would not be able to regain attitude control after the Orbiter undocked. The core issues associated with recovering long-term attitude control using CMGs are described, as well as the systems engineering analysis to identify recovery options. It is shown that the recovery method can be separated into a procedure for rate damping to a "safe harbor" gravity gradient stable orientation and a capability to maneuver the vehicle to the necessary initial conditions for long-term attitude hold. A manual control option using Soyuz and Progress vehicle thrusters is investigated for rate damping and maneuvers. The issues with implementing such an option are presented and the key issue of closed-loop stability is addressed. A new nonpropulsive alternative to thruster control, the Zero Propellant Maneuver (ZPM) attitude control method is introduced and its rate damping and maneuver performance is evaluated. It is shown that ZPM can meet the tight attitude and rate error tolerances needed for long-term attitude control. A combination of manual thruster rate damping to a "safe harbor" attitude followed by a ZPM to stage long-term attitude control orientation was selected by the Anomaly Resolution Team as the alternate attitude control method for such a contingency.

Subjects: ATTITUDE CONTROL, RECOVERY, ZERO PROPELLANT MANEUVER (ZPM), THRUSTERS, INTERNATIONAL SPACE STATION (ISS)

Bedrossian, N.S.; Bhatt, S.A.

Space Station Zero Propellant Maneuver Flight Results Compared to Eigenaxis

Space Flight Mechanics, Galveston, TX, 1/27/2008-1/31/2008. Sponsored by: AAS and AIAA (Draper Report no. P-4631)

Abstract: The first-ever Zero Propellant Maneuver (ZPM) rotated the International Space Station (ISS) 90 deg without using propellant on November 5, 2006. On March 3, 2007, another ZPM reoriented the ISS 180 deg, also without any propellant use. This paper describes the ZPM concept and presents the flight results for these two particular ZPMs in comparison to the corresponding eigenaxis trajectories. The reason a ZPM trajectory can avoid momentum saturation while the eigenaxis cannot is presented. The ZPMs are preplanned trajectories used to command the Control Moment Gyro (CMG) attitude hold controller to perform the maneuver between specified initial and final states while maintaining the CMGs within their operational limits. Each trajectory is obtained by computationally solving an optimal attitude control problem with pseudospectral methods. The ZPM thus provides the capability to control the rotational state of a spacecraft (e.g., large-angle maneuvers, rate damping, momentum dumping, etc.) without the need to use thrusters.

Subjects: ZERO PROPELLANT MANEUVER (ZPM), INTERNATIONAL SPACE STATION (ISS), TRAJECTORIES

Bedrossian, N.S.; Bhatt, S.A.; Lammers, M.L.; Nguyen, L.; Zhang, Y.

Zero-Propellant Maneuver Concept and Flight Results

Air Force Test & Evaluation (T&E) Days, Los Angeles, CA, 2/5/2008-2/7/2008. Sponsored by: AIAA (Draper Report no. P-4633)

Abstract: This paper presents the Zero Propellant Maneuver (ZPM) rotational control concept and its demonstrations in flight. On November 5, 2006, a ZPM was used to reorient the International Space Station (ISS) 90 deg without using any propellant. In addition, a ZPM was used to perform a 180-deg ISS rotation on March 3, 2007. The ZPMs are preplanned trajectories used to command the Control Moment Gyro (CMG) attitude hold controller to perform the maneuver between specified initial and final states while maintaining the CMGs within their operational limits. Each trajectory was obtained from a computational solution to an optimal attitude control problem. The ZPM thus provides the capability to perform large-angle attitude maneuvers, rate damping, momentum desaturation, etc., without the need to use thrusters. This approach is applicable to any spacecraft controlled by momentum storage devices.

Subjects: ZERO PROPELLANT MANEUVER (ZPM), MANEUVERS, TRAJECTORIES, INTERNATIONAL SPACE STATION (ISS)

Bernstein, J.J.; Bancu, M.G.; Ciocan, R.; Lenkinski, R.E.; Marquis, R.P.; Ivanishev, A.; Frangioni, J.V.

Micro RF Tags for Medical Imaging

Solid-State Sensor, Actuator, and Microsystems Workshop, Hilton Head Island, SC, 6/1/2008-6/5/2008. Sponsored by: Transducers Research Foundation (TRF) (Draper Report no. P-4658)

Abstract: This paper presents Micro Resonant Devices (MRDs), which are visible in magnetic resonance imaging (MRI) scans. These LC resonators are fabricated using electroplated spiral inductors combined with thin-film Ta₂O₅ capacitors, formed by a novel oxy-nitride plasma oxidation process. Arrays of resonators were fabricated with diameters of 0.3, 0.5, and 1 mm. To compensate for process variations, resonators were fabricated with parametrically varying capacitor areas. In this study, we characterize the first such devices for their detectability as a function of size in salt-containing aqueous media and in vivo using a clinical MRI scanner and a scanning ultrahigh-frequency (UHF) microscope.

Subjects: MICRODEVICES, IMAGING, MAGNETIC RESONANCE IMAGING (MRI)

Bettinger, C.J.; Bruggeman, J.P.; Langer, R.; Borenstein, J.T.

Amino Alcohol-Based Elastomeric Poly(ester amide)s for Hepatic Tissue Engineering

TERMIS-NA Annual Conference & Exposition, San Diego, CA, 12/7/2008-12/10/2008. Sponsored by: Tissue Engineering International and Regenerative Medicine Society (Draper Report no. P-4735)

Abstract: Synthetic biodegradable materials have enormous utility in biomedical applications, including tissue engineering. Numerous synthetic biodegradable elastomers have been developed for scaffold fabrication. Currently available synthetic biodegradable materials exhibit undesirable properties including (1) extremely high crosslinking densities resulting in high modulus materials, (2) rapid biodegradation upon implantation, or (3) limited functional groups to increase the suite of available chemistries for covalent conjugation of biomolecules, including proteins and growth factors. We synthesized a new class of biodegradable elastomeric poly(ester amide)s based on the amino alcohol 1,3-diamino-2-hydroxypropane (DABP), termed APS polymers, to overcome the limitations in existing synthetic bioelastomers. We also demonstrate the use of this new class of materials for potential use in hepatic tissue engineering applications.

Subjects: TISSUE ENGINEERING, BIODEGRADABLE ELASTOMER, SCAFFOLDS

Bettinger, C.J.; Zhang, Z.; Langer, R.; Gerecht, S.; Borenstein, J.T.

Enhancement of In Vitro Capillary Tube Formation with Synthetic Nanotopography

Technical Proceedings of the Nanotechnology Science and Technology Institute (NSTI), Boston, MA, 6/1/2008-6/5/2008. Sponsored by: NSTI (Draper Report no. P-4663A)

Abstract: Tissue engineering scaffolds often aim to control cell behavior using a variety of signaling modalities, including chemistry, mechanical properties, and local microenvironmental factors such as oxygen concentration. However, few efforts have explored the use of nanotopography as a means to regulate cell function. Controlling the morphology and function of cells using substrate nanotopography is a phenomenon that can be utilized in a variety of fields, including tissue engineering and regenerative medicine. In this work, we explored the possibility of using nanofabricated surfaces to control the function of endothelial cells to ultimately enhance in vitro vasculargenesis. We chose to culture endothelial progenitor cells (EPCs) on poly(dimethylsiloxane) substrates with ridge-groove geometries of approximately 600 nm in width. EPCs cultured on nanotopographic were found to exhibit enhanced morphological alignment and elongation, reduced proliferation, and enhanced migration. Protein-level expression of endothelial cell markers was not significantly affected by topography, as determined by fluorescent microscopy. However, an in vitro capillary tube formation assay induced the formation of larger, more organized vascular structures in EPCs cultured on nanotopographic versus flat substrates. These results suggest substrate nanotopography could function as a tool for controlling EPC function and achieving enhanced vasculargenesis. Furthermore, these nanotopographic substrates could serve as a template for engineering more complex vascularized tissues and organs.

Subjects: TISSUE ENGINEERING, NANOTOPOGRAPHY, CELLS, MANIPULATING

Bloom, I.B.

Aging Behavior of Master Bond EP29LPSP as Determined by Thermal Analysis

American Chemical Society (ACS) New England Regional Meeting (NERM), Burlington, VT, 6/29/2008-7/2/2008. Sponsored by: ACS (Draper Report no. P-4677A)

Abstract: We used a combination of standard thermal analysis techniques to measure the aging behavior of the cured epoxy system of Master Bond EP29LPSP. Both mechanical and thermal properties were measured for Master Bond. This material has a number of interesting properties. For example, it has a very low Young's modulus at temperatures above 40 deg centigrade. On the other hand, it is difficult to make a homogeneous mixture with Master Bond EP29LPSP. This latter fact has made it difficult for us to obtain good reproducibility. The way in which we have overcome the issue of homogeneity and its effect on the variability of the measured properties is a major theme of this presentation. Four thermal analysis techniques are employed: TGA, DSC, TMA, and DMA. The TGA was used to develop a correlation between aging time and aging temperature. This correlation was the basis of our accelerated aging study. Some properties, like transition temperature, were measured by more than one technique (DMA and DSC). The results for our measurement of the transition temperature and others are compared and evaluated.

Subjects: THERMAL ANALYSIS, EPOXIES, TECHNIQUE

Borenstein, J.T.; Fiering, J.O.; Tao, S.L.; Mescher, M.J.; Swan, E.E.; Holmboe, M.E.; Kujawa, S.G.; McKenna, M.J.; Sewell, W.F.; Chen, Z.; Peppi, M.; Murphy, B.

Micromechanical Device for Intracochlear Drug Delivery

Draper Public Web, June 2008 (Draper Report no. P-4725)

Abstract: Recent developments in cochlear physiology and molecular biology paved the way for new and innovative ways of treating and presenting sensorineural hearing loss, ultimately benefiting millions of individuals. Treatment with these emerging bioactive compounds will require a safe and effective drug delivery mechanism directly into the inner ear. Through this collaborative research and development program between Draper Laboratory and the Massachusetts Ear and Eye Infirmary, we are designing, developing, and testing a wearable and ultimately implantable intracochlear drug delivery system. This device will be capable of delivering multiple simple and complex compounds over periods of months to years, with precise control and regulation of sequence and rate of delivery.

Subjects: DRUG DELIVERY, INNER EAR, IMPLANTABLE DEVICES

Carlen, E.T.; Weinberg, M.S.; Dubé, C.E.; Zapata, A.M.; Borenstein, J.T.

Micromachined Surface Stress Sensor with Electronic Readout

Review of Scientific Instruments, Vol. 79, 015106, 1/2008 (Draper Report no. P-4569)

Abstract: A micromachined surface stress sensor has been fabricated and integrated off chip with a low-noise, differential capacitance, electronic readout circuit. The differential capacitance signal is modulated with a high-frequency carrier signal, and the output signal is synchronously demodulated and filtered, resulting in a DC output voltage proportional to the change in differential surface stress. The differential surface stress change of the Au(lll) coated silicon sensors due to chemisorbed alkanethiols is Δσ_s≈-0.42±0.0028 Nm^-1 for 1-dodecanethiol (DT) and Δσ_s≈-0.14±0.0028 Nm^-1 for 1-butanethiol (BT). The estimated measurement resolution (1-Hz bandwidth) is ≈0.12 mNm^-1 (DT: 0.2 pg mm^-2 and BT: 0.8 pg mm^-2) and as high as  ≈3.82 µNm^-1 (DT: 8 fg mm^-2 and BT: 24 fg mm^-2) with system optimization.

Subjects: MICROELECTROMECHANICAL SYSTEMS (MEMS), SURFACE STRESS SENSORS, CAPACITANCE

Cohanim, B.E.; Collins, B.K.

Real-time Landing Point Redesignation (LPR) Algorithm

2008 Guidance, Navigation, and Control Conference and Exhibit, Honolulu, HI, 8/18/2008-8/21/2008. Sponsored by: AIAA (Draper Report no. P-4698)

Abstract: In order to achieve a safe, precise, and efficient landing on the moon, a number of factors must be considered in real-time during the critical descent phase. These factors include locating hazardous boulders, craters, and slopes, identifying predeployed assets and science areas, and managing fuel consumption. This paper describes an algorithm that trades off the factors laid out above and selects landing points based on input terrain and vehicle data. Inputs to the algorithm are the lander footprint, divert fuel costs, detected hazards, and identified points of interest. The algorithm is designed to accept any number of input cost functions and constraints, ensuring flexibility to a variety of missions. The input cost functions are weighted and then fed into a search algorithm that returns all feasible landing points on the map, prioritized by the weighted cost function. The algorithm is capable of returning overlapping or nonoverlapping solutions. This algorithm is designed to provide onboard crew or autonomous robotic vehicles with real-time landing point redesignation capabilities.

Subjects: ALGORITHMS, GUIDANCE NAVIGATION AND CONTROL (GN&C), LUNAR DESCENT, AUTONOMOUS PRECISION LANDING AND HAZARD DETECTION AND AVOIDANCE TECHNOLOGY (ALHAT)

Charest, J.L.; Weinberg, E.J.; Hsiao, J.C.; Borenstein, J.T.

Numerical Modeling, Microfabrication, and Cell Adhesion Testing of a Tissue Engineered Loop of Henle Device

SFA Translational Biomaterials Research Symposium, Atlanta, GA, 9/11/2008-9/13/2008. Sponsored by: Society of Biomaterials (Draper Report no. P-4752)

Abstract: End-stage renal disease (ESRD) often results in poor patient outcomes since kidney function restoration options and therapeutics are limited. Tissue-engineered devices can aid treatment of ESRD by potentially restoring renal function as well as providing characterized in vitro platforms for therapeutic research. In particular, a tissue-engineered Loop of Henle (LOH) would provide a means to concentrate waste streams, thereby reducing renal assist device size, while providing an in vitro model replicating physiological architecture. Here, a modeling of a tissue-engineered nephron device including an LOH shows the potential of the LOH to significantly concentrate solutes in the waste stream. The device design incorporates a membrane in conjunction with a cellularized biomaterial layer in a well-controlled microfabricated device in order to mimic LOH functionality and architecture. Device material selection and surface treatments enable potential cellularization with kidney-specific cells.

Subjects: RENAL REPLACEMENT SYSTEM, TISSUE ENGINEERING, DEVICES, MODELING

Deutsch, O.L.; Parry, J.R.

Long Endurance UUVs for Precursor ASW Search and Barrier Operations

Submarine Technology Symposium (SUBLANT), Johns Hopkins University, MD, 5/13/2008-5/15/2008. Sponsored by: Naval Submarine League (Draper Report no. P-4686)

Abstract: Future technology to counter the anti-access threat posed by diesel-electric submarines (SSKs) augments SSNs with distributed and networked forces and unmanned vehicles. Because Anti-Submarine Warfare (ASW) is such an inherently difficult mission, a balanced portfolio of assets is required to ensure mission accomplishment under a wide variety of challenges. Naval aviation, organic fleet assets, and special assets such as Surveillance Towed Array Sonar System/Low Frequency Active (SURTASS)/(LFA) will each play critical roles in different circumstances. The proposed concept uses long endurance Unmanned Underwater Vehicles (UUVs) to fill a capability gap for large area, deep water sweep and barrier screening. The concept UUVs are 10-ton class and are powered by diesel-electric power plants for endurance and logistical supportability. They would operate active sonar at depth to perform detection only, and would cue existing ASW assets for persistent tracking and prosecution.

Subjects: UNMANNED UNDERWATER VEHICLES (UUV), ANTISUBMARINE WARFARE, DETECTION

D'Souza, C.N.; Clark, F.D.

Linear Covariance Analysis Techniques Applied to Orion Cislunar Operations

Space Flight Mechanics Conference, Galveston, TX, 1/27/2008-1/31/2008. Sponsored by: AAS and AIAA (Draper Report no. R-3018)

Abstract: Linear covariance techniques are applied to the cislunar phase of the Orion mission. Both the guidance and navigation systems are analyzed, particularly as they relate to 3-sigma navigation performance and trajectory dispersion. In addition the deltaV statistics will be presented. This paper documents the preliminary integrated analyses performed to provide the expected onboard dispersion and navigation errors.

Subjects: LINEAR COVARIANCE ANALYSIS,CREW EXPLORATION VEHICLES (CEV),CISLUNAR SPACE

Dubach, J.M.; Clark, H.A.; Das, S.; Rosenzweig, A.

Optical Nanosensors for Intracellular Sodium Analysis

Lasers & Electro-Optics Society Biophotonics, Newport Beach, CA, 11/9/2008-11/13/2008. Sponsored by: IEEE (Draper Report no. P-4729)

Abstract: Calcium is one of the major components of multiple signaling pathways that govern cellular behavior and activity. Calcium signaling has been studied intensely for over 20 years due to the availability of calcium indicator dyes. These sensors are specific for calcium over other significant interfering ions in the cellular environment and bright enough to provide signal in basic microscopy setups. The range of measurement tools developed so far enables researchers to study the different calcium concentration levels present in the cytosol and subcellular compartments such as the endoplasmic reticulum. Like calcium, sodium plays a major role in cellular activity, particularly in excitable cells such as cardiac myocytes. However, unlike calcium, less is known about the function of sodium in the intracellular environment. Sodium influx into the call is the first event of an action potential and triggers the downstream events that cause a myocyte to contract. Numerous candidate drugs have failed FDA trials due to alterations caused in ion flux during cardiac myocyte contractions. Therefore, the ability to study sodium dynamics in excitable cells may provide information on adverse effects of drugs. Furthermore, a greater understanding of subcellular sodium dynamics, such as sodium “sparks,” will allow researchers to target specific components of sodium dynamics when studying myocytes.

Subjects: SODIUM, NANOSENSORS, CELLS (BIOLOGY

Epp, C.D.; Robertson, E.; Brady, T.M.

Autonomous Landing and Hazard Avoidance Technology

Aerospace Conference, Big Sky, MT, 3/1/2008-3/8/2008. Sponsored by: IEEE (Draper Report no. P-4657)

Abstract: The ALHAT Project is funded by NASA to develop an integrated AGN&C (Autonomous Guidance, Navigation and Control) hardware and software system capable of detecting and avoiding surface hazards and guiding humans and cargo safely, precisely, and repeatedly to designated lunar landing sites. There are important interdependencies driving the design of a lunar landing system, including such things as lander hazard robustness, landing site conditions (terrain and natural lighting), trajectories, sensors, crew involvement, and others. The ALHAT system must be capable of operating in a wide range of lunar environments and supporting global lunar access for both crewed and robotic missions. This paper discusses the major factors driving the design of a lunar landing system as well as the current state of the technology development. The supporting analysis and testing results will be presented that show the system interdependencies and their relative importance, as well as the trades needed to optimize the landing system. The emphasis is on the final phase of the landing where Hazard Detection and Avoidance (HDA) and Hazard-Relative Navigation (HRN) are the primary considerations in achieving a safe landing. The current sensor options being considered and the status of the development of those sensors are discussed.

Subjects: AUTONOMOUS GUIDANCE, NAVIGATION, AND CONTROL (AGN&c), AUTONOMOUS HAZARD DETECTION AND AVOIDANCE, LUNAR LANDING

Forest, L.M.; Cohanim, B.E.; Kessler, L.J.; Brady, T.M.

Human Interactive Landing Point Redesignation for Lunar Landing

Aerospace Conference, Big Sky, MT, 3/1/2008-3/8/2008. Sponsored by: IEEE (Draper Report no. P-4597A)

Abstract: In order to achieve safe and precise landings anywhere on the lunar surface without the heavy involvement of mission operations required during Apollo, an Autonomous Flight Manager (AFM) is needed to assist the crew in managing the landing mission. An essential algorithm within the AFM is the Landing Point Redesignation (LPR) function, which determines a prioritized list of safe and precise points in the landing region from which the crew can select a landing aimpoint. The LPR function described in this paper is flexible enough to support a variety of missions and situations by allowing an operator to reach in and modify parameters prior to and throughout the landing.

Subjects: LUNAR LANDING, AUTONOMOUS FLIGHT MANAGER (AFM), ALGORITHMS

Geisler, M.A.

Expedition MCM-D Layout for Multilayer Die

MARLUG Conference, Laurel, MD, 5/28/2008. Sponsored by: International Mentor Graphics Users Group (Draper Report no. P-4711)

Abstract: Powerpoint presentation with a preview of the manufacturing process, defining corresponding Expedition layers, creating die cells, Expedition layout setup, Expedition layout, buried part shortcomings, and automation.

Subjects: ELECTRONIC DESIGN AUTOMATION, MANUFACTURING, GRAPHICS, LAYOUTS

Gustafson, D.E.; Bottkol, M.S.; Parry, J.R.; Elwell Jr., J.M.; Nguyen, T.Q.

Indoor Geolocation Using RF Multipath with Probabilistic Data Association

Position Location and Navigation Symposium (PLANS), Monterey, CA, 5/5/2008-5/8/2008. Sponsored by: IEEE/ION (Draper Report no. P-4663)

Abstract: An indoor navigation problem is considered where the objective is real-time tracking of transponding tags in multipath environments using signals sent from and received at a set of radio frequency (RF) sources at fixed and known locations. Current systems depend on detection of direct path signals and treat multipath signals as spurious. We present an approach for exploiting the multipath signals to maintain tracking when direct paths are undetected. The method relies on estimating the parameters of minimum-complexity models of the indirect path lengths. A maximum of three parameters is required to model indirect path lengths arising from an arbitrary number of specular reflections off planar surfaces. A probabilistic data association filter (PDAF) is used to mitigate uncertainties arising from noise, closely-spaced path lengths, and path length crossovers. The method is tested via simulation using bandlimited signals synthesized from ray trace data. Performance is compared with an optimized direct path filter using Monte Carlo analysis. No prior knowledge of multipath parameters or indoor infrastructure is assumed, and measurements are restricted to time-of-arrival (TOA) only. The results indicate that the PDAF consistently outperforms the direct path filter when one or more direct paths are blocked.

Subjects: NAVIGATION, RADIO FREQUENCY (RF), PATHS

Hart, J.J.; King, E.T.; Miotto, P.; Lim, S.

Orion GN&C Architecture for Increased Spacecraft Automation and Autonomy Capabilities

Guidance, Navigation, and Control Conference and Exhibit, Honululu, HI, 8/18/2008-8/21/2008. Sponsored by: AIAA (Draper Report no. P-4728)

Abstract: The Orion Crew Exploration Vehicle has requirements for automation and autonomy that exceed the capabilities of the Space Shuttle and the International Space Station. The Orion requirements call for automated rendezvous and docking, automated ascent aborts, and automated deorbit burns among other requirements, which result in a spacecraft with a higher level of autonomy from ground-based support. While increased levels of automated functionality provide the autonomy necessary for extended duration missions, it also imposes additional requirements to ensure the capability to monitor and control the automated capabilities. This paper presents the guidance, navigation, and control (GN&C) architecture developed to satisfy these requirements and safely provide the desired increase in spacecraft automation. The joint NASA and Lockheed Martin GN&C team with support from Draper Laboratory is designing the GN&C architecture described in this paper. The design will provide the interface to the Orion "Timeline Manager" software, which contains the knowledge of the overall mission plan. This mission plan is broken into Mission Segments, which represent the low-level decomposition of the mission timeline, e.g., burn maneuvers and other critical events. The GN&C architecture is designed with a hierarchical structure to sequence through the GN&C activities necessary to complete the objectives of the current Mission Segment. Each GN&C activity will be used to configure the individual GN&C modes. To satisfy control of automation and flexibility requirements, the GN&C architecture must also provide an interface that allows crew and ground operators to access critical GN&C functionality during automation operations and manually configure the GN&C subsystem when necessary. This flexibility is intended to prevent the development of a “brittle” architecture that cannot accommodate the dynamic and unpredictable nature of human space flight. This paper outlines the preliminary Orion GN&C architecture and describes a functional prototype of the GN&C architecture created using object-oriented design philosophies in the Matlab/Simulink environment. A unique design and code generation process employing Unified Modeling Language (UML) modeling practices was used to capture the design, ensure requirement traceability, and generate working prototype Matlab and C-code.

Subjects: CREW EXPLORATION VEHICLES (CEV), GUIDANCE NAVIGATION AND CONTROL (GN&C), AUTOMATION

Hattis, P.D.; Moran, B.A.

Enabling Robust and Reliable Spacecraft Function

31st Guidance and Control Conference, Breckenridge, CO, 2/1/2008-2/6/2008. Sponsored by: AAS (Draper Report no. P-4622) 

Abstract: Contemporary spacecraft must realize high levels of reliability while demonstrating robustness to the space environment. This must be done while accommodating tight constraints on component weight, power, and volume as well as meeting mission-specific performance requirements. This paper addresses and compares some of the applicable Guidance, Navigation and Control (GN&C) design trades and solution options for earth orbital spacecraft, vehicles traveling beyond earth orbit, and vehicles transiting an atmosphere during entry from space. Some GN&C-specific component selection considerations associated with spacecraft operating in Earth orbit, cis-lunar flight, lunar orbit, earth entry, and Mars entry are reviewed with account for applicable reliability requirements, performance objectives, and vehicle design constraints.

Subjects: GUIDANCE NAVIGATION AND CONTROL (GN&C), SPACECRAFT REENTRY, SPACECRAFT

Homer, M.L.; Lim, S.; Lopez, J.E.; Corbett, M.

Machine-Aided Design of an Air-Launched Missile Defense System

Missile Sciences Conference, Monterey, CA, 11/18/2008-11/20/2008. Sponsored by: AIAA. (Draper Report no. P-4644)

Abstract: The power of today's computers is altering design methodologies at the system level. Instead of manually comparing and contrasting a dozen or so options for configuring a system, machine aids can now quantitatively evaluate thousands of candidate configurations on the time scale of minutes. We apply a machine aid to improve the design of an air-launched missile defense system that intercepts ballistic targets during both their boost and terminal phases. First, the specific problem statement and corresponding quantitative formulation are defined. The discussion then moves on to the overall procedure executed by the machine aid, followed by delving into the quantitative models employed. Calculations include those for generating interceptor and target trajectories, obtaining the fire control solution, and simulating the end game. Later sections of the paper report results as well as the analytical methods employed to elicit dominant trends. The findings point to promising directions one should pursue in order to boost the system's performance and suggestions for the machine aid itself might usefully evolve.

Subjects: MACHINE DESIGN, MISSILE SYSTEMS, SYSTEM PERFORMANCE

Ji, J.; O'Connell, J.G.; Carter, D.J.; Larson, D.N.

High-Throughput Nanohole Array-Based System to Monitor Multiple Binding Events in Real Time

Analytical Chemistry, ACS, Vol. 80, No. 7, 4/1/2008, pp. 2491-2498 (Draper Report no. P-4595)

Abstract: We have developed an integrated label-free, real-time sensing system that is able to monitor multiple biomolecular binding events based on the changes in the intensity of extraordinary optical transmission (EOT) through nanohole arrays. The core of the system is a sensing chip containing multiple nanohole arrays embedded within an optically thick gold film, where each array functions as an independent sensor. Each array is a square array containing 10 x 10 nanoholes (150 nm in diameter), occupying a total area of 3.3 µm x 3.3 µm. The integrated system includes a laser light source, a temperature-regulated flow cell encasing the sensing chip, motorized optics, and a charge-coupled detector (CCD) camera. For demonstration purposes, sensing chips containing 25 nanohole arrays were studied for their use in multiplexed detection, although the sensing chip could be easily populated to contain up to 20 164 nanohole arrays within its 0.64 cm² sensing area. Using this system, we successfully recorded 25 separate binding curves between glutathione S-transferase (GST) and anti-GST simultaneously in real time with good sensitivity. The system responds to binding events in a concentration-dependent manner, showing a sharp linear response to anti-GST at concentrations ranging from 13 to 290 nM. The EOT intensity-based approach also enables the system to monitor multiple bindings simultaneously and continuously, offering a temporal resolution on a milliseconds scale that is decided only by the camera speed and exposure time. The small footprint of the sensing arrays combined with the EOT intensity-based approach enables the system to resolve binding events that occurred on nanohole sensing arrays spaced 96 µm apart, with a reasonable prediction of resolving binding events spaced 56 µm apart. This work represents a new direction that implements nanohole arrays and EOT intensity to meet high-throughput, spatial and temporal resolution, and sensitivity requirements in drug discovery and proteomics studies.

Subjects: NANOHOLES, ARRAYS, SENSING

Katti, R.R.; Lintz, J.; Sundstrom, L.; Marques, A.M.; Scoppettuolo, S.C.; Martin, D.

Heavy-Ion and Total Ionizing Dose (TID) Performance of a 1-Mbit Magnetoresistive Random Access Memory (MRAM)

Nuclear and Space Radiation Effects Conference (NSREC), Tuscon, AZ, 7/14/2008-7/18/2008. Sponsored by: IEEE (Draper Report no. P-4612)

Abstract: A 1-Mbit Magnetoresistive Random Access Memory (MRAM) is a nonvolatile memory that has been developed, demonstrated electrically and functionally, and subjected to radiation testing.  The 1-Mbit MRAM supports heavy ion immunity to a Linear Energy Transfer (LET) level through approximately 69 MeV-cm2/mg for fluences to 10⁷ to 10⁸ ions/cm and Total Ionizing Dose (TID) hardness in excess of 1 Mrad.

Subjects: MEMORY DEVICES, IONS, RADIATION

Madison, R.W.; DeBitetto, P.A.; Olean, A.R.; Peebles, M.

Target Geolocation from a Small Unmanned Aircraft System

Aerospace Conference, Big Sky, MT, 3/1/2008-3/8/2008. Sponsored by: IEEE (Draper Report no. P-4602)

Abstract: Draper Laboratory and AeroVironment, Inc. of Monrovia, CA, are implementing a system to demonstrate target geolocation from a Raven-B Unmanned Aircraft System (UAS) as part of the U.S. Army Natick Soldier Research, Development & Engineering Center's Small UAS (SUAS) Advanced Concept Technology Demonstration (ACTD). The system is based on feature tracking, line-of-sight calculation, and Kalman filtering from Draper's autonomous vision-aided navigation code base. The system reads imagery and telemetry transmitted by the UAS and includes a user interface for specifying targets. Tests on a snapshot of ongoing work indicate horizontal targeting accuracy of approximately 10 m, compared with 20-60 m for the current Raven-B targeting software operating on the same flight video/telemetry streams. This accuracy likely will be improved through further mitigation of identified error sources. This paper presents our targeting architecture, the results of tests on simulator and flight data, an analysis of remaining error, and suggestions for reducing that error.

Subjects: TARGET GEOLOCATION, UNMANNED AERIAL SYSTEMS (UAS)

Mahdavi, A.; Ferreira, L.S.; Sundback, C.A.; Nichol, J.W.; Chan, E.; Carter, D.J.; Bettinger, C.J.; Patanavanich, S.; Chignozha, L.; Joseph, E.B.; Galakatos, A.; Pryor, H.; Pomerantseva, I.; Masiakos, P.T.; Faquin, W.C.; Zumbuehl, A.; Hong, S.; Borenstein, J.T.; Vacanti, J.P.; Langer, R.; Karp, J.M.

Biodegradable and Biocompatible Gecko-Inspired Tissue Adhesive

Proceedings of the National Academy of Sciences of the USA, Vol. 105, No. 7, 2/19/2008, pp. 2307-2312 (Draper Report no. P-4626)

Abstract: There is a significant medical need for tough biodegradable polymer adhesives that can adapt to or recover from various mechanical deformations while remaining strongly attached to the underlying tissue. We approached this objective by utilizing a novel polymer poly(glycercol sebacic acid acrylate) (PGSA) and modifying the surface to mimic the nanotopography of gecko feet, which allows attachment to vertical surfaces. Translation of existing gecko-inspired adhesives for medical applications is complex as multiple parameters must be optimized, including biocompatibility, biodegradation, strong adhesive tissue bonding, and compliance and conformational matches to tissue surfaces. Ideally these adhesives would also have the ability to deliver drugs or growth factors to promote healing. As a first demonstration, we have created a gecko-inspired tissue adhesive from a biocompatible and biodegradable elastomer combined with a thin tissue reactive, biocompatible surface coating. Tissue adhesion was optimized by varying dimensions of the nanoscale pillars, including the ratio of tip diameter to pitch and the ratio of tip diameter to base diameter. Coating these nanomolded pillars of biodegradable elastomers with a thin layer of oxidized dextran significantly increased the interfacial adhesion strength on porcine intestine tissue in vitro and in the rat abdominal subfascial in vivo environment. This gecko-inspired medical adhesive has potential applications for sealing wounds and for replacement or augmentation of sutures or staples.

Subjects: POLYMERS,TISSUES, ADHESIVES

Mangoubi, R.S.; Desai, M.N.; Sammak, P.J.

Performance Evaluation of Stem Cell Multiresolution Texture Analysis

5th International Symposium on Biomedical Imaging: From Nano to Macro, Paris, France, 5/14/2008-5/17/2008. Sponsored by: IEEE (Draper Report no. P-4617)

Abstract: We apply texture image analysis methods to the problem of automated classification of stem cell nuclei. Using known probability models for the coefficients of texture multiresolution decompositions, we derive likelihood ratio test statistics. We also derive the probability density functions of these non-Gaussian statistics and use them to evaluate the performance of the classification test. Results indicate that the likelihood ratio test can successfully distinguish with probability 0.95 between nuclei that are pluripotent and those with varying degrees of differentiation. The test also recognizes when two nuclei whose level of differentiation is similar by assigning them to the same class, even if prior information says the contrary. Finally, the test statistics and their density functions are applicable to a general texture classification problem.

Subjects: STEM CELLS, TEXTURE CLASSIFICATION

Marinis, T.F.; Soucy, J.W.; Lawrence, J.G.; Marinis, R.T.; Pryputniewicz, R.J.

Vacuum-Sealed MEMS Package with an Optical Window

58th Electronics Components & Technology Conference, Lake Buena Vista, FL, 5/27/2008-5/30/2008. Sponsored by: IEEE (Draper Report no. P-4659)

Abstract: A vacuum-sealed package with an optical window is a useful diagnostic tool for Microelectromechanical Systems (MEMS) devices, as well as a critical component of optical devices, such as imaging bolometers, scanning mirrors, and variable wavelength filters. In either of these applications, the package must meet a number of stringent requirements. It cannot contaminate devices by either outgassing or shedding particulates. The window must be optically flat to allow devices to be observed or measured with interferometric tools when the package is used as a diagnostic tool. When it serves as an integral part of an optical MEMS device, the window must also have the requisite transmissibility over the device's operating wavelength range. The vacuum level in many applications can also be quite challenging to achieve. Typically, pressures less than a few millitorr are necessary to prevent gas damping from limiting attainable Q values. Packages utilized for diagnostic purposes are often subjected to harsh environmental testing to evaluate how MEMS devices respond to mechanical shock, vibration, or thermal shock. Consequently, package robustness, particularly the glass-to-package seal integrity, is an important design element. We have successfully used a sputtered composite structure of gold over platinum over titanium to fabricate a seal ring on the window. The window is attached to a leadless ceramic chip carrier package by soldering with a 50 microns thick eutectic gold-tin preform. The sealing process is to load package assemblies, preforms and windows into a high-vacuum system, degas them, raise the temperature of all components to 325C, bring them into contact, and cool. We have used finite-element analysis (FEM) to optimize the seal geometry as a function of coefficient of thermal expansion (CTE) mismatch, solder material, and window material to meet environmental requirements and optical flatness specifications. We have validated these FEM calculations by subjecting sealed packages to mechanical shock and helium leak testing. The optical flatness of windows was evaluated by direct optical interferometry measurements and high-resolution measurements on sealed MEMS devices. The gas permeability of sealed packages was evaluated by measuring the Q of resonant devices over a period of several months. This fundamental understanding of window design, validated by experimental testing, extends our MEMS packaging capability to support the needs of both diagnostic investigations and optical device packaging.

Subjects: MICROELECTROMECHANICAL SYSTEMS (MEMS), OPTICAL DEVICES

Milenkovic, Z.

Estimate of Burn Error for Open-Loop Guidance Maneuvers During Proximity Operations

2008 Guidance, Navigation, and Control Conference and Exhibit, Honolulu, HI, 8/18/2008-8/21/2008. Sponsored by: AIAA (Draper Report no. P-4733)

Abstract: During proximity operations translational ∆V commands are sent from guidance to control for execution. In many cases, the guidance solution assumes an impulsive burn; for open-loop guidance, i.e., for ∆Vs that are computed only once, a finite burn effect could mar the accuracy of the solution. If the guidance solution was calculated with such an assumption, the difference between the final achieved state and the desired state increases with the duration of the burn. A basic example is depicted in Figure 1. The diagram shows a chaser co-elliptic with the target orbit. The impulsive change in velocity required at the burn point in order to meet the desired final state can only be achieved with infinite acceleration. Since it is impossible to impart a discrete change in velocity, the burn requires a certain time (∆t) to execute.

Subjects: PROXIMITY OPERATIONS, MANEUVERS, OPEN-LOOP SYSTEMS, BURN

Miller, M.A.; Barton, G.H.

Managing Energy and Mode Transitions in Orion Skip Entry Guidance

2008 Guidance, Navigation, and Control Conference and Exhibit, Honolulu, HI, 8/18/2008-8/21/2008. Sponsored by: AIAA (Draper Report no. P-4654)

Abstract: Skip entry trajectories provide a technique for returning an astronaut crew from the Moon to a continental United States landing site at any time during the lunar month. This approach to atmospheric entry requires that the guidance system be capable of precisely targeting a vast array of downrange distances. To meet this objective, Draper Laboratory has developed a baseline skip entry guidance algorithm that is a blend of the original Apollo guidance logic and a numeric targeting algorithm, PredGuid, that is used for the skip portion of the entry. The addition of PredGuid greatly improved the algorithm's performance for skip trajectories, but numerous simplifications and Apollo-based empirical relationships still limit the capability of the algorithm and may be unsuitable for other vehicle configurations. Enhancements to the Draper baseline that redesign the energy management system and phase transition logic are presented. A model-based predictor has been developed to determine the type of trajectory that is necessary to cover the target range and the appropriate time to transition to the next flight mode, based on the trajectory type. The direct entry capability has been improved and expanded by incorporating a variable constant drag policy to manage energy, and by designing specific direct entry reference trajectories, which are used by the path-following controller in the final descent phase. In addition, an intermediate loft regime is introduced to bridge the range capability between direct and skip entries. These upgrades to the baseline algorithm greatly improve its robustness to uncertainties encountered through the entry, as demonstrated via Monte Carlo simulations, using the Crew Exploration Vehicle capsule concept. This algorithm design also offers the ability to optimize a skip trajectory to meet a particular set of objectives by modifying the reference skip bank angle.

Subjects: SKIP ENTRY TRAJECTORIES, ALGORITHMS, ENTRY GUIDANCE

Osenar, M.J.; Clark, F.D.; D'Souza, C.N.

Performance of an Automated Feature Tracking Lunar Navigation System

Space Flight Mechanics Conference, Galveston, TX, 1/27/2008-1/31/2008. Sponsored by: AAS and AIAA (Draper Report no. R-3019)

Abstract: The performance of this automated lunar landmark system has been investigated using linear covariance techniques. Lunar surface feature tracking will be shown to be an effective method for lunar navigation using a digital camera. The camera has been shown to improve performance primarily by decreasing downrange position error in subsequent sightings of a particular feature. Error analysis has shown that the limited knowledge of lunar gravity is the biggest hindrance to navigation performance. With a large feature set and a wide camera field of view, active feature tracking is expected to achieve a 3-sigma RSS position error of under 500 m, and 3-sigma RSS velocity error under 3 m/s in low lunar orbit.

Subjects: LUNAR NAVIGATION, LINEAR COVARIANCE ANALYSIS, LUNAR SURFACE

Page, L.A.; Nervegna, M.F.; DiBiaso, D.M.

Unmanned System Risk Management

International Conference on Robotics and Automation, Pasadena, CA, 5/19/2008-5/23/2008. Sponsored by: IEEE (Draper Report no. P-4592)

Abstract: This paper describes Unmanned System Risk Management, a methodology for managing the risks involved in unmanned vehicle missions. The methodology includes a human/machine collaborative process for risk management that is embedded into a system's broader process for initiating a mission. The methodology also includes an architecture that structures how risk-related information flows throughout the distributed system and how risk information is collected from and presented to the user. It also includes the development and integration of algorithms dedicated to managing specific categories of risk. Each risk category is supported by specific risk analysis and/or mitigation algorithms. The architecture is extendable so that developers can incorporate additional, risk-category-specific algorithms over time without needless complexity. The methodology has been implemented in the Risk-aware Mixed-initiative Dynamic Replanning (RMDR) system, which allows an operator to manage a heterogeneous team of unmanned underwater and air vehicles. RMDR includes autonomy functionality onboard the vehicles as well as on a host platform with an operator in the loop. RMDR currently includes algorithms to analyze and/or mitigate the risks of being detected, of colliding with other vehicles, of running out of energy, and of image collection failure due to environmental conditions. Risk mitigation algorithms are incorporated into both team-level and vehicle-level plan generation.

Subjects: UNMANNED SYSTEMS,RISK MANAGEMENT, RISK-AWARE MIXED-INITIATIVE DYNAMIC REPLANNING PROGRAM (RMDR)

Paschall II, S.C.; Sostaric, R.; Cohanim, B.E.; Brady, T.M.

Self-Contained Method for Safe and Precise Lunar Landing

Aerospace Conference, Big Sky, MT, 3/1/2008-3/8/2008. Sponsored by: IEEE (Draper Report no. P-4598)

Abstract: The return of humans to the Moon will require increased capability beyond that of the previous Apollo missions. Longer stay times and a greater flexibility with regard to landing locations are among the many improvements planned. A descent and landing system that can land the vehicle more accurately than Apollo with a greater ability to detect and avoid hazards is essential to the development of a Lunar Outpost and also for increasing the number of potentially reachable Lunar Sortie locations. This descent and landing system should allow landings in more challenging terrain and provide more flexibility with regard to mission timing and lighting considerations, while maintaining safety as the top priority. The lunar landing system under development by the ALHAT (Autonomous precision Landing and Hazard Avoidance Technology) project is addressing this by providing terrain-relative navigation measurements to enhance global-scale precision, an onboard hazard-detection system to select safe landing locations, and an Autonomous Guidance, Navigation, and Control (GN&C) capability to process these measurements and safely direct the vehicle to this landing location. This ALHAT landing system will enable safe and precise lunar landings without requiring lunar infrastructure in the form of navigation aids or a priori identified hazard-free landing locations. The safe landing capability provided by ALHAT uses onboard active sensing to detect hazards that are large enough to be a danger to the vehicle, but too small to be detected from orbit, given current orbital terrain resolution limits. Algorithms to interpret raw active sensor terrain data and generate hazard maps, as well as to identify safe sites and recalculate new trajectories to those sites are included as part of the ALHAT system. These improvements to descent and landing will help contribute to repeated safe and precise landings on the Moon.

Subjects: LUNAR LANDING, AUTONOMOUS PRECISION LANDING AND HAZARD DETECTION AND AVOIDANCE TECHNOLOGY (ALHAT), MOON MISSIONS, GUIDANCE NAVIGATION AND CONTROL (GN&C)

Slusarz, J.; Larson, D.N.; Ellis, H.J.

Automated Frozen Sample Aliquotting System

Annual Conference, Bethesda, MD, 5/18/2008-5/21/2008. Sponsored by: International Society for Biological and Environmental Repositories (Draper Report no. P-4700)

Abstract: Concept: Extract an aliquot from a frozen biological sample without thawing it and automate the process.

Subjects: AUTOMATION, EXTRACTION, ALIQUOT

Thompson, J.C.; Tepolt, G.B.; Racz, L.M.; Rogers, C.B.

A Method for Die Thickness Reduction to sub-35 µm

2008 Materials Research Society (MRS) Fall Meeting, Boston, MA, 12/1/2008-12/5/2008. Sponsored by: MRS (Draper Report no. P-4803)

Abstract: Significant system performance improvements can be realized by stacking die layers. This approach, known as 3-D integration, can reduce RC delay as well as the system form factor. Die are typically thinned in wafer form prior to integration into the modules, allowing even greater functional density. However, certain applications require the thinning of individual die. A detailed technique, including die lamination, lapping, chemical mechanical planarization (CMP), and release has been developed to thin die to 35 µm thickness. During lamination, the die are temporarily adhered with their active side down to a glass substrate using an adhesive. Mechanical lapping is performed to remove the majority of silicon from the back side. The final thickness of approximately 35 µm is achieved using CMP. The CMP step is critical for the removal of subsurface damage and prevention of device failure. After thinning, the adhesive is dissolved and the die are handled using porous end effectors. The process can effectively produce die thinned to 35 µm with ± 1.5 µm total thickness variation (TTY).

Subjects: DIES, METHODOLOGY, SYSTEM PERFORMANCE

Turyshev, S.G.; Lane, B.F.; Shao, M.

Search for New Physics with the BEACON Mission

Astronomical Telescopes and Instrumentation, Marseille, France, 6/23/2008-6/28/2008. Sponsored by: SPIE (Draper Report no. P-4708)

Abstract: The primary objective of the Beyond Einstein Advanced Coherent Optical Network (BEACON) mission is a search for new physics beyond general relativity. In doing so, BEACON will measure the curvature of relativistic space-time as characterized by the Eddington parameter g. This parameter is the most fundamental relativistic gravity parameter and is a direct measure for the presence of new physical interactions. BEACON will achieve an accuracy of a part in a billion in measuring the parameter gamma, thereby going a factor of 30,000 beyond the current best result—the 2003 test involving the Cassini spacecraft. Secondary mission objectives include: (i) a direct measurement of the "frame-dragging" and geodetic precessions in the Earth's rotational gravitomagnetic field to 0.05% and 0.03% accuracy correspondingly, (ii) first measurement of gravity's nonlinear effects on light and the second-order spatial metric's effects to 0.01% accuracy. BEACON will lead to robust advances in tests of fundamental physics. This mission could discover a violation or extension of general relativity and/or reveal the presence of an additional long-range interaction in physics. BEACON will provide crucial information to separate modern scalar-tensor theories of gravity from general relativity, probe possible ways for gravity quantization, and test modern theories of cosmological evolution.

Subjects: PHYSICS, GRAVITY, RELATIVITY

Weinberg, E.J.; Borenstein, J.T.; Kaazempur-Mofrad, M.R.

Concept and Computational Design for a Bioartificial Nephron-on-a-Chip

International Journal of Artificial Organs, Vol. 31, No. 6, 2008 (Draper Report no. P-4607)

Abstract: A MEMS-based, bioartificial device is proposed for replicating the function of a single nephron. Consistent with the anatomy and physiology of a human, our device has three distinct sections, replicating the function of the glomerulus, the proximal tubule, and the Loop of Henle. Construction of a bioartificial Loop of Henle in particular requires control of diffusion-scale features. The proposed device can be built using existing microfabrication technologies and populated with various renal cell types. A computational model is also developed to analyze the coupled, multiphase mass transport in this system. Using the model, a design is generated with flow and solute transport properties.

Subjects: MICROELECTROMECHANICAL SYSTEMS (MEMS), RENAL REPLACEMENT SYSTEM, NEPHRON, KIDNEY, COMPUTATIONAL MODELING

Zanetti, Renato

Autonomous Mid-Course Navigation for Lunar Return

Astrodynamics Specialist Conference, Honolulu, HI, 8/18/2008-8/21/2008. Sponsored by: AAS/AIAA (Draper Report no. P-4784)

Abstract: A method for autonomous lunar return navigation system is developed. Autonomy is achieved using optical sensors and celestial navigation. The available measurements are the elevation of known stars from the Earth or Moon's limb and the apparent radius of the Earth or Moon. Measurements and error models for celestial navigation are developed with the aid of Monte Carlo methods and are used to support the study. Navigation errors and trajectory dispersions are obtained with linear covariance techniques to confirm the feasibility of the approach. The results show that the proposed autonomous navigation system meets the reentry safety requirements.

Subjects: CELESTIAL NAVIGATION, AUTONOMOUS NAVIGATION, LINEAR COVARIANCE ANALYSIS

Zanetti, R.; Hanak, F.C.

Relative Navigation for the Orion Vehicle

F. Landis Markley Astronautics Symposium, Cambridge, MD, 6/29/2008-7/2/2008. Sponsored by: American Astronautical Society. (Draper Report no. P-4726)

Abstract: The Orion vehicle is being designed to provide manned spaceflight capability after the retirement of the Space Shuttle in 2010. Orion will provide access to both the International Space Station and the Moon. In both cases, the vehicle is required to perform rendezvous, and therefore requires a relative navigation filter. This paper documents the preliminary analysis performed by the Orion navigation team, and reviews the current Orion relative navigation architecture as well as the sensors available for rendezvous and proximity operations.

Subjects: CREW EXPLORATION VEHICLES (CEV), NAVIGATION SYSTEMS, SENSORS