11 to 20 of 815 Results
Jun 22, 2022
Wang, Daniel; Russino, Joseph A.; Basich, Connor; Chien, Steve, 2022, "Analyzing the Efficacy of Flexible Execution, Replanning, and Plan Optimization for a Planetary Lander", https://hdl.handle.net/2014/56174, ICAPS 2022 - International Conference on Automated Planning and Scheduling, Singapore Management University, Singapore, June 22-24, 2022, JPL Open Repository
Plan execution in unknown environments poses a number of challenges: uncertainty in domain modeling, stochasticity at execution time, and the presence of exogenous events. These challenges motivate an integrated approach to planning and execution that is able to respond intellige... |
Jun 19, 2022
Kim, Mina; Wang, Cheng; Yi, Lin; Lee, Hae-Seung; Han, Ruonan, 2022, "A Sub-THz CMOS Molecular Clock with 20 ppt Stability at 10,000 s Based on A Dual-Loop Spectroscopic Detection and Digital Frequency Error Integration", https://hdl.handle.net/2014/56149, The 2022 Radio Frequency Integrated Circuits Symposium, Denver, Colorado, June 19-21, 2022, JPL Open Repository
This paper presents a dual-loop chip-scale molecular clock (CSMC), which enhances the Allan Deviation performance by combining high signal-to-noise ratio of using fundamental mode and long-term stability of using higher order modes in derivative molecular absorption spectroscopy.... |
Jun 8, 2022
Mohseni, Nima; Bernstein, Dennis S.; Quadrelli, Marco M, 2022, "Adaptive Force Control for Small Celestial Body Sampling", https://hdl.handle.net/2014/55930, American Control Conference 2022, Atlanta, Georgia, June 8-10, 2022, JPL Open Repository
An adaptive force control algorithm for small celestial body sampling for a variety of surface properties is developed. The control algorithm consists of an adaptive controller combined with feedback linearization. When a spacecraft makes contact with the surface, it must maintai... |
Jun 6, 2022
Abrams, M.; Yamaguchi, Y.; Crippen, R., 2022, "Aster Global Dem (gdem) Version 3", https://hdl.handle.net/2014/56151, ISPRS Congress, Nice, France, June 6-11, 2022, JPL Open Repository
The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is a 14-channel imaging instrument operating on NASA’s Terra satellite since 1999. ASTER’s visible–near infrared (VNIR) instrument, with three bands and a 15 m Instantaneous field of view (IFOV), is accomp... |
Jun 5, 2022
Gupta, Gaurangi; Decrossas, Emmanuel; Chahat, Nacer, 2022, "All-Metal Dual Band Circular Polarized UHF Patch Antenna", https://hdl.handle.net/2014/56142, Wireless Antenna and Microwave Symposium (WAMS) 2022, Rourkela, India, June 5-8, 2022, JPL Open Repository
An all-metal circularly polarized UHF antenna element is presented. The patch antenna gives a wideband impedance and axial ratio bandwidth of 24% over the 0.3-0.38 GHz frequency band with 90% efficiency. The main advantage is the use of a single feed point to generate circular po... |
May 26, 2022
Allison, Tim; Burke, Wayne; Mattmann, Chris; Mensikova, Anastasija; Milano, Mike; Southam, Philip; Stonebraker, Ryan, 2022, "Research Report: Progress on Building a File Observatory for Secure Parser Development", https://hdl.handle.net/2014/56133, LangSec Workshop at IEEE Security & Privacy, Pasadena, California, May 26, 2022, JPL Open Repository
Parsing untrusted data is notoriously challenging.Failure to handle maliciously crafted data correctly can (anddoes) lead to a wide range of vulnerabilities. The Languagetheoretic security (LangSec) philosophy seeks to obviate the needfor developers to apply ad hoc solutions by,... |
May 24, 2022
Chien, Steve, 2022, "Formal Methods for Trusted Space Autonomy, Boon or Bane?", https://hdl.handle.net/2014/56170, NFM 2022 - NASA Formal Methods, Pasadena, California, May 24-27, 2022, JPL Open Repository
Trusted Space Autonomy is challenging in that space systems are complex artifacts deployed in a high stakes environment with complicated operational settings. Thus far these challenges have been met using the full arsenal of tools: formal methods, informal methods, testing, runti... |
May 23, 2022
Duarte Lopes Mascarenhas Proenca, Pedro; Delaune, Jeff; Brockers, Roland, 2022, "Optimizing Terrain Mapping and Landing Site Detection for Autonomous UAVs", https://hdl.handle.net/2014/55924, International Conference on Robotics and Automation 2022, Philadelphia, Pennsylvania, May 23-26, 2022, JPL Open Repository
The next generation of Mars rotorcrafts requires on-board autonomous hazard avoidance landing. To this end, this work proposes a system that performs continuous multi- resolution height map reconstruction and safe landing spot detection. Structure-from-Motion measurements are agg... |
May 11, 2022
Aaron, Kim; Johnson, Duval; Worel, Shana; Tao, Frank, 2022, "Bearing Starting Torque Measurements Down to –100°C", https://hdl.handle.net/2014/56146, 46th Aerospace Mechanisms Symposium, Houston, Texas, May 11-13, 2022, JPL Open Repository
Starting torque was measured for three different bearings from 0°C down to 90°C and 100°C. These are bearings of the type that will be used in the ice-penetrating radar instrument named Radar for Europa Assessment and Sounding: Ocean to Near-surface (REASON), which is part of the... |
May 11, 2022
Drymiotis, Fivos; Smith, Cassie; Schein, Mike, 2022, "Low Temperature Brazing: A Candidate Method for Preventing Interplanetary Contamination During the Mars Sample Return Mission", https://hdl.handle.net/2014/55988, 46th Aerospace Mechanisms Symposium, Houston, Texas, May 11-13, 2022, JPL Open Repository
NASA and the European Space Agency are planning a joint Mars Sample Return campaign, scheduled to launch in 2026, with a very specific objective: return to Earth the rock and regolith samples that have been collected on Mars by NASA’s Perseverance rover. This is a very complex, m... |
