ebook img

NASA Technical Reports Server (NTRS) 20120006596: Patched Conic Trajectory Code PDF

0.19 MB·English
Save to my drive
Quick download
Download
Most books are stored in the elastic cloud where traffic is expensive. For this reason, we have a limit on daily download.

Preview NASA Technical Reports Server (NTRS) 20120006596: Patched Conic Trajectory Code

of candidate IRIS spacecraft mission or- culate air vehicle stability in a variety of Data Distribution System bits in an accurate and timely fashion. critical flight conditions. The code is (DDS) and Solar Dynamic The software is a suite of Fortran subrou- based on fundamental, non-linear equa- Observatory Ground Station tines and data files organized as a “com- tions of motion and is able to translate (SDOGS) Integration Manager putational” engine that is used to accu- results into a qualitative, graphical scale The DDS SDOGS Integration Manager rately predict the long-term orbit useful to the non-expert. (DSIM) provides translation between na- evolution of IRIS mission orbits while MASCOT was created to provide the tive control and status formats for systems searching for Earth shadow conditions. conceptual aircraft designer accurate within DDS and SDOGS, and the ASIST The core algorithms of this software predictions of air vehicle stability and (Advanced Spacecraft Integration and product have been used to solve a variety control characteristics. The code takes System Test) control environment of unique orbital mechanics and target- as input mass property data in the form in the SDO MOC (Solar Dynamics Obser- ing problems. Past applications include of an inertia tensor, aerodynamic load- vatory Mission Operations Center). lunar shadow requirements for Chan- ing data, and propulsion (i.e. thrust) This system was created in response for dra, perigee decay of geosynchronous loading data. Using fundamental non- a need to centralize remote monitor and transfer orbits due to third-body point- linear equations of motion, MASCOT control of SDO Ground Station equip- mass perturbations, and prediction of or- then calculates vehicle trim and static ments using ASIST control environment bital lifetime and decay of Earth satellites. stability data for the desired flight condi- in SDO MOC, and to have configurable This work was done by David Eagle of a.i. tion(s). Available flight conditions in- table definition for equipment. It pro- solutions Inc. for Kennedy Space Center. For ad- clude six horizontal and six landing rota- vides translation of status and monitoring ditional information, contact David Eagle at tion conditions with varying options for information from the native systems into (321) 867-8913. KSC-13519 engine out, crosswind, and sideslip, plus ASIST-readable format to display on three take-off rotation conditions. Re- pages in the MOC. sults are displayed through a unique The manager is lightweight, user graphical interface developed to pro- friendly, and efficient. It allows data trend- Automated and vide the non-stability and control expert ing, correlation, and storing. It allows Manual Rocket Crater conceptual design engineer a qualitative using ASIST as common interface for re- Measurement Software scale indicating whether the vehicle has mote monitor and control of heteroge- An update has been performed to soft- acceptable, marginal, or unacceptable neous equipments. It also provides fail- ware designed to do very rapid automated static stability characteristics. If desired, over capability to back up machines. measurements of craters created in sandy the user can also examine the detailed, This work was done by Kim Pham and substrates by rocket exhaust on liftoff. quantitative results. Thomas Bialas of Goddard Space Flight Center. The previous software was optimized for This work was done by Sean P. Kenny of Further information is contained in a TSP pristine lab geometry and lighting condi- Langley Research Center and Luis Crespo of the (see page 1).GSC-16020-1 tions. This software has been enhanced to National Institute of Aerospace. Further infor- include a section for manual measure- mation is contained in a TSP (see page 1). ments of crater parameters; namely, LAR-17483-1 crater depth, crater full width at half max, Eclipse-Free-Time Assess- and estimated crater volume. The tools ment Tool for IRIS provide a very rapid method to measure IRIS_EFT is a scientific simulation that these manual parameters to ease the bur- Patched Conic can be used to perform an Eclipse-Free- den of analyzing large data sets. Trajectory Code Time (EFT) assessment of IRIS (Infrared This software allows for rapid quantiza- PatCon code was developed to help Imaging Surveyor) mission orbits. EFT is tion of the rocket crater parameters where mission designers run trade studies on defined to be those time intervals longer automated methods may not work. The launch and arrival times for any given than one day during which the IRIS progress of spreadsheet data is continuously planet. Initially developed in Fortran, the spacecraft is not in the Earth’s shadow. saved so that data is never lost, and data can required inputs included launch date, ar- Program IRIS_EFT implements a special be copied to clipboards and pasted to other rival date, and other orbital parameters perturbation of orbital motion to numeri- software for analysis. The volume estimation of the launch planet and arrival planets at cally integrate Cowell’s form of the system of a crater is based on the central max depth the given dates. These parameters in- of differential equations. Shadow condi- axis line, and the polygonal shape of the clude the position of the planets, the ec- tions are predicted by embedding this in- crater is integrated around that axis. centricity, semi-major axes, argument of tegrator within Brent’s method for find- This work was done by Philip Metzger of periapsis, ascending node, and inclina- ing the root of a nonlinear equation. The Kennedy Space Center and Christopher Immer tion of the planets. With these inputs, a IRIS_EFT software models the effects of of ASRC Aerospace Corp. Further information patched conic approximation is used to the following types of orbit perturbations is contained in a TSP (see page 1).KSC-13386 determine the trajectory. on the long-term evolution and shadow The patched conic approximation di- characteristics of IRIS mission orbits: vides the planetary mission into three (cid:129) Non-spherical Earth gravity, parts: (1) the departure phase, in which (cid:129) Atmospheric drag, MATLAB Stability and the two relevant bodies are Earth and the (cid:129) Point-mass gravity of the Sun, and Control Toolbox Trim and spacecraft, and where the trajectory is a (cid:129) Point-mass gravity of the Moon. Static Stability Module departure hyperbola with Earth at the The objective of this effort was to create MATLAB Stability and Control focus; (2) the cruise phase, in which the an in-house computer program that Toolbox (MASCOT) utilizes geometric, two bodies are the Sun and the spacecraft, would perform eclipse-free-time analysis aerodynamic, and inertial inputs to cal- and where the trajectory is a transfer el- 18 NASA Tech Briefs, January 2012 lipse with the Sun at the focus; and (3) the robust against non-elliptical details of the tain threshold during each use of the Wal- arrival phase, in which the two bodies are image and against noise. lops Flight Facility Launch Range. Under the target planet and the spacecraft, Interferometric analysis of precision-ma- the variable conditions that can exist at where the trajectory is an arrival hyper- chined surfaces remains an important launch time, the decision to launch must bola with the planet as the focus. technological instrument in hardware de- be made in a timely manner to ensure a This work was done by Brooke Anderson velopment and quality analysis. This soft- successful mission while not exceeding Park and Henry Wright of Langley Research ware automates and increases the accuracy those risk criteria. Range safety officers Center. Further information is contained in a of this technique. The software has been need a tool that can give them the needed TSP (see page 1).LAR-17446-1 developed for the needs of an R&TD- probability of impact information quickly, funded project and has become an impor- and in a format that is clearly understand- tant asset for the future research proposal able. This application is meant to fill that to NASA as well as other agencies. need. Ring Image Analyzer This work was done by Dmitry V. Strekalov of The software is a reuse of part of soft- Ring Image Analyzer software analyzes Caltech for NASA’s Jet Propulsion Laboratory. ware developed for an earlier project: images to recognize elliptical patterns. It Further information is contained in a TSP Ship Surveillance Software System (S4). determines the ellipse parameters (axes (see page 1).This software is available for com- The S4 project was written in C++ using ratio, centroid coordinate, tilt angle). mercial licensing. Please contact Daniel Broder- Microsoft Visual Studio 6. The data The program attempts to recognize el- ick of the California Institute of Technol- structures and dialog templates from it liptical fringes (e.g., Newton Rings) on a ogy at [email protected]. Refer to were copied into a new application that photograph and determine their cen- NPO-47579. calls the implementation of the algo- troid position, the short-to-long-axis rithms from S4 and displays the results ratio, and the angle of rotation of the as needed. In the S4 software, the list of long axis relative to the horizontal direc- ships in the area was received from one tion on the photograph. These capabili- SureTrak Probability of local radar interface and from operators ties are important in interferometric im- Impact Display who entered the ship information man- aging and control of surfaces. In The SureTrak Probability of Impact Dis- ually. The SureTrak Probability of Im- particular, this program has been devel- play software was developed for use during pact Display application receives ship oped and applied for determining the rocket launch operations. The software data from two local radars as well as the rim shape of precision-machined optical displays probability of impact information SureTrak system, eliminating the need whispering gallery mode resonators. for each ship near the hazardous area dur- for manual data entry. The program relies on a unique image ing the time immediately preceding the This work was done by John Elliott of God- recognition algorithm aimed at recogniz- launch of an unguided vehicle. dard Space Flight Center. Further information ing elliptical shapes, but can be easily Wallops range safety officers need to be is contained in a TSP (see page 1). GSC- adapted to other geometric shapes. It is sure that the risk to humans is below a cer- 16064-1 NASA Tech Briefs, January 2012 19

See more

The list of books you might like

Most books are stored in the elastic cloud where traffic is expensive. For this reason, we have a limit on daily download.