Search NASASearch

Engineering topics

Daniel R. Wibben

Publications and source records attributed to Daniel R. Wibben.

Navigation Prediction Performance During OSIRIS-REx Proximity Operations at (101955) Bennu

The OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification and Security–Regolith Explorer) Orbit Determination team performed covariance analyses prior to the commencement of proximity operations (ProxOps) at (101955) Bennu to determine the expected predicted trajectory performance in order to meet trajectory knowledge requirements throughout each phase of the mission. One of the primary requirements placed on the predicted trajectory performance was based on the performance during orbital phases leading up to the maneuver to initiate the Touch-and-Go (TAG) trajectory descent. Throughout ProxOps the nominal force models being used to predict the spacecraft trajectory were updated in an effort to improve the prediction performance. The most significant models that contributed to prediction performance were of solar radiation pressure, thermal reradiation of the spacecraft, predicted attitude errors, and desaturation maneuvers. Efforts were made throughout all of ProxOps to monitor, trend, predict, and update spacecraft modeling to improve the prediction performance. These efforts were vital to reduce the spacecraft knowledge errors necessary to achieve a TAG target smaller than pre-launch analysis allowed due to the rough terrain of Bennu. Increased precision in predicted trajectory errors allowed for refined uncertainties to be used for future phase planning throughout the mission. The navigation team successfully predicted the spacecraft trajectory throughout all of ProxOps achieving predicted trajectories errors less than originally analyzed.

Jason M. Leonard

Trajectory Design and Maneuver Performance of the OSIRIS-REx Low-Altitude Reconnaissance of Bennu

With more than a year of asteroid proximity operations, the OSIRIS-REx team was able to identify one primary and one backup site for sample collection. The next step was to finalize on-board, localized image libraries and site-specific terrain information prior to attempting sample acquisition. Collecting this information required additional, low-altitude asteroid flyby reconnaissance activities. These activities, referred to as ‘sorties’, involved special maneuver and trajectory designs, unique from any other OSIRIS-REx maneuver activity. In order to minimize time between flybys and decrease the total number of maneuvers required, this trajectory design departed from and returned to a frozen Sun-terminator plane orbit within the span of a few hours. This work discusses the trajectory design and performance of the four flybys that were used to collect key topographic science observations of the primary and backup sample sites, which helped lead to a successful sample collection.

Andrew Levine

OSIRIS-REx Orbit Trim Strategy

One of the more challenging aspects of the trajectory design for the OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer) mission at asteroid Bennu was maneuvering while in orbit. The orbital dynamics were highly perturbed by various sources, most notably solar radiation pressure, which degraded accuracy of long term predictions of the spacecraft’s location in orbit. Generally, the Navigation team had to solve three separate issues: correcting a perturbed orbit, changing to a different orbit, or phasing the or bitto place the spacecraft at a specific location at a specific time. The team composed a common framework using up to two maneuvers that could solve all of these problems using an identical schedule that allowed for consistent planning long before the final trajectory could be designed. This orbit trim strategy was successfully used for the first time in the Orbital B phase of the mission to maximize the duration of usable observing geometry in a time-variable orbit with strict operational limits. It was used an additional 3 times throughout the mission to adjust and/or change the orbit, most notably altering the orbit in the weeks prior to the successful Touch-And-Go (TAG)sample collection attempt. This same strategy was used to phase the orbit a total 10 times in preparation for each of the science sorties over potential sample sites, the TAG Rehearsals, and TAG. The trim strategy was demonstrated to be robust and performed exceptionally well in all aspects, which proved critical to a successful sample collection.

Daniel R. Wibben

Small-Body Proximity Operations & TAG: Navigation Experiences & Lessons Learned from the OSIRIS-REx Mission

On October 20th, 2020, the nearly two-year proximity operations campaign for the Origins, Spectral Interpretation, Resource Identification, and Security–Regolith Explorer (OSIRIS-REx)mission at the near-Earth asteroid (101955) Bennu culminated in a successful Touch-and-Go (TAG) sample collection event. Navigation performance was a significant driver for flight activities at Bennu, which consisted of multiple phases geared towards characterizing the asteroid, selecting a sample site, and safely guiding the spacecraft to and from the surface in order to collect at least 60 g of pristine regolith. The entire operations team gained a tremendous amount of experience operating in the challenging small body environment and overcame many challenges. In this paper, we summarize navigation-focused experiences and lessons learned from OSIRIS-REx proximity operations at Bennu that are applicable to future missions to small asteroids, comets, and planetary moons. Areas of focus include staffing and organization, ground system infrastructure, mission phase planning, navigation operations, and spacecraft and payload considerations.

Kenneth M. Getzandanner

Concept of Operations for OSIRIS-REx Optical Navigation Image Planning

Optical navigation (OpNav) is a critical subsystem of the OSIRIS-REx asteroid sample return mission, which operated in the vicinity of near-Earth asteroid (101955) Bennu from August 2018 through April 2021. A substantial amount of mission resources across multiple subsystems and institutions is required to ensure that the OpNav data are successfully acquired. The KinetX OpNav team, part of the Flight Dynamics System (FDS), is responsible for performing required analysis to develop the OpNav operations plans; requesting, reviewing and verifying the plans; and ultimately using the image data for critical navigation operations. The FDS team, responsible for the mission navigation, is operated by KinetX Aerospace with management and operations support from NASA’s Goddard Space Flight Center. The Science Processing and Operations Center (SPOC), located at the University of Arizona’s Lunar and Planetary Laboratory, is responsible for generating the planning products for all science and most OpNav data. These plans are integrated into the spacecraft sequences, tested, and commanded by the Mission Support Area (MSA) at Lockheed Martin Space. To ensure mission-critical navigation image data are successfully acquired, the plan is developed through a waterfall of planning cycles over the course of 3 months prior to onboard plan execution. During the initial strategic planning for a mission phase, detailed analysis is performed by the OpNav team to conceptualize the concept of operations (ConOps) for image data collection. This phase OpNav Narrative is included along with other strategic planning documents for the key ground segment stakeholders to review and provide feedback. The detailed OpNav plans get defined in the tactical planning cycle, which spans 8 to 3 weeks before the week-long integrated sequence is executed on-board the spacecraft. During the tactical cycle, the initial OpNav Request is submitted along with the science requests, kicking off development of the science and OpNav plans. Once the initial plan is drafted, interfaces are exercised so that the plan can be reviewed and iterated, if necessary. A rigorous schedule is followed by the planning teams during the implementation cycle, spanning the last 18 days before uplink, to ensure all the necessary integration, testing, and reviewing can occur on time. The development of the OpNav planning ConOps, including responsibilities, interfaces, timelines, and procedures, took extensive collaboration across mission elements and institutions. The process was robust throughout the 137 weeks of continuous Optical Navigation Operations at Bennu, which concluded on April 9th, 2021.

Coralie D. Adam

Lucy Mission Design Strategy in a Dynamic Operations Environment from Launch Through First Asteroid Encounter

Lucy, a 12-yearlong NASA Discovery-class mission which launched on October 16, 2021will fly by several Jupiter-Trojan asteroids a t the L4 and L5 La grange points. Prior to theL4 Trojan encounter in 2027 and 2028, Lucy will utilize two Earth gravity-assist flybys and fly by two main-belt a steroids. After the L4 encounters a third Earth flyby will set up the L5 Troja n encounter in 2033. This pa per summarizes the baseline mission plan with focus on the spacecraft trajectory and the corresponding essential trajectory correction maneuvers as well as how the Lucy team adapted to many unforeseen changes to the spacecraft configuration and added an asteroid target of opportunity that required changes to the baseline mission plan. Refinement of asteroid flyby science requirements after launch also required updates to the baseline Lucy trajectory.

James V. Mcadams

OSIRIS-REx Earth Return & Entry: Navigation Operations & Lessons Learned

The Origins, Spectral Interpretation, Resource Identification, and Security–Regolith Explorer (OSIRIS-REx) spacecraft successfully returned to Earth on September24, 2024, safely delivering its Sample Return Capsule (SRC) to the Utah Test and Training Range (UTTR). This paper describes the navigation operations that occurred between the departure from Bennu and the return of the SRC. An overview is given of the Flight Dynamics System (FDS) that includes tracking, orbit determination (OD), maneuver planning, and interfaces with entry, descent, and landing. Operational details on the SRC release criteria and conjunction assessment considerations are also provided. Lessons learned are presented that may help future sample return or interplanetary entry missions.

Kenneth M. Getzandanner

OSIRIS-REx Earth Return & Entry: Targeting Strategy and Maneuver Performance

The OSIRIS-REx sample return capsule landed safely in the Utah desert on September 24, 2023. Starting with the departure from asteroid Bennu in May 2021 through the release of the sample capsule and its arrival at the edge of Earth’s atmosphere hours later, this phase of the mission was planned and analyzed thoroughly to optimize the probability of a successful sample return in a large number of nominal and off-nominal scenarios, all while emphasizing spacecraft safety. This paper discusses the spacecraft and sample capsule Earth return and atmospheric entry trajectory design, maneuver analysis, and flight performance, which ultimately helped lead to a successful sample return and initiation of the OSIRIS-APEX extended mission.

Daniel R. Wibben

Leveraging Resonant Terminator Orbits for the Trajectory Design of OSIRIS-APEX at (99942) Apophis

The OSIRIS-REx spacecraft has been approved for an extended mission (OSIRIS-APEX) to visit the asteroid (99942) Apophis. In this paper we outline a potential design for the spacecraft’s trajectory during the variable phase orbit segment of the APEX mission. This phase of the mission, nominally expected to begin in January2030, has the primary goal of collecting image and spectral data of the full asteroid surface at a wide variety of illumination conditions without requiring frequent firing of the spacecraft thrusters. This work will focus on leveraging resonant terminator orbits (RTOs) in order to satisfy these goals and the associated science requirements. Though this segment will occur after Apophis’ closest flyby of Earth in April 2029, the proposed design utilizes the current best estimates of the asteroid’s orbital elements and physical properties at that time when designing the spacecraft’s orbit.

Gavin M Brown