The pole-sitter mission concept : an overview of recent developments and possible future applications

The paper provides a survey of novel mission concepts for continuous, hemispheric polar observation and direct-link polar telecommunications. It is well known that these services cannot be provided by traditional platforms: geostationary satellites do not cover high-latitude regions, while low- and medium-orbit Sun-synchronous spacecraft only cover a narrow swath of the Earth at each passage. Concepts that are proposed in the literature are described, including the pole-sitter concept (in which a spacecraft is stationary above the pole), spacecraft in artificial equilibrium points in the Sun-Earth system and non-Keplerian polar Molniya orbits. Additionally, novel displaced eight-shaped orbits at Lagrangian points are presented. For many of these concepts, a continuous acceleration is required and propulsion systems include solar electric propulsion, solar sail and a hybridisation of the two. Advantages and drawbacks of each mission concept are assessed, and a comparison in terms of high-latitude coverage and distance, spacecraft mass, payload and lifetime is presented. Finally, the paper will describe a number of potential applications enabled by these concepts, focusing on polar Earth observation and telecommunications

Lessons for Interstellar Travel from the G&C Design of the NEA Scout Solar Sail Mission

NASA is developing the Near Earth Asteroid (NEA) Scout mission that will use a solar sail to travel to an asteroid where it will perform a slow flyby to acquire science imagery. A guidance and control system was developed to meet the science and trajectory requirements. The NEA Scout design process can be applied to an interstellar or precursor mission that uses a beam-propelled sail. The scientific objectives are met by accurately targeting the destination trajectory position and velocity. The destination is targeted by understanding the force on the sail from the beam (or sunlight in the case of NEA Scout) over the duration of the thrust maneuver. The propulsive maneuver is maintained by accurate understanding of the torque on the sail, which is a function of sail shape, optical properties, and mass properties, all of which apply to NEA Scout and beam propelled sails. NEA Scout uses active control of the sail attitude while trimming the solar torque, which could be used on a beamed propulsion sail if necessary. The biggest difference is that NEA Scout can correct for uncertainties in sail thrust modeling, spacecraft orbit, and target orbit throughout the flight to the target, while beamed propulsion needs accurate operation for the short duration of the beamed propulsion maneuver, making accurate understanding of the sail thrust and orbits much more critical

Lessons for Interstellar Travel from the Guidance and Control Design of the Near Earth Asteroid Scout Solar Sail Mission

NASA is developing the Near Earth Asteroid (NEA) Scout mission that will use a solar sail to travel to an asteroid where it will perform a slow flyby to acquire science imagery. A guidance and control system was developed to meet the science and trajectory requirements. The NEA Scout design process can be applied to an interstellar or precursor mission that uses a beam propelled sail. The scientific objectives are met by accurately targeting the destination trajectory position and velocity. The destination is targeted by understanding the force on the sail from the beam (or sunlight in the case of NEA Scout) over the duration of the thrust maneuver. The propulsive maneuver is maintained by accurate understanding of the torque on the sail, which is a function of sail shape, optical properties, and mass properties, all of which apply to NEA Scout and beam propelled sails. NEA Scout uses active control of the sail attitude while trimming the solar torque, which could be used on a beamed propulsion sail if necessary. The biggest difference is that NEA Scout can correct for uncertainties in sail thrust modeling, spacecraft orbit, and target orbit throughout the flight to the target, while beamed propulsion needs accurate operation for the short duration of the beamed propulsion maneuver, making accurate understanding of the sail thrust and orbits much more critical

Lessons for Interstellar Travel from the Guidance and Control Design of the Near Earth Asteroid Scout Solar Sail Mission

NASA's Near Earth Asteroid Scout (NEA Scout) solar sail mission will fly by and image an asteroid. The team has experience characterizing the sail forces and torques used in guidance, navigation, and control to meet the scientific objectives. Interstellar and precursor sail missions similarly require understanding of beam riding dynamics to follow sufficiently accurate trajectories to perform their missions. Objective: Identify the driving factors required to implement a guidance and control system that meets mission requirements for a solar sail mission; Compare experience of an asteroid flyby mission to interstellar missions to flyby and observe other stars or precursor missions to study the extrasolar medium

Sunjammer: A Solar Sail Demonstration

No abstract availabl

Novel mission concepts for polar coverage : An overview of recent developments and possible future applications

The paper provides a survey of novel mission concepts for continuous, hemispheric polar observation and direct-link polar telecommunications. It is well known that these services cannot be provided by traditional platforms: geostationary satellites do not cover high-latitude regions, while low- and medium-orbit Sun-synchronous spacecraft only cover a narrow swath of the Earth at each passage. Concepts that are proposed in the literature are described, including the pole-sitter concept (in which a spacecraft is stationary above the pole), spacecraft in artificial equilibrium points in the Sun-Earth system and non-Keplerian polar Molniya orbits. Additionally, novel displaced eight-shaped orbits at Lagrangian points are presented. For many of these concepts, a continuous acceleration is required and propulsion systems include solar electric propulsion, solar sail and a hybridisation of the two. Advantages and drawbacks of each mission concept are assessed, and a comparison in terms of high-latitude coverage and distance, spacecraft mass, payload and lifetime is presented. Finally, the paper will describe a number of potential applications enabled by these concepts, focusing on polar Earth observation and telecommunications

Digital Map Complexity and Behavioral Consistency in Mobility Information Systems

Digitally enabled mobility services and their associated information systems (IS) have spread rapidly in recent times, for example in the form of smartphone and in-vehicle applications. Such services often enable users to achieve more environmentally friendly, equitable, and safe individual mobility. User interfaces typically feature digital maps to facilitate spatial orientation and choice. This study pioneers an investigation of digital maps for low-stake decision making as prevalent in mobility IS. To this end, we blend previous theoretical research on task and map complexity from other disciplines. By analyzing data from a discrete choice experiment, we confirm the hypothesized relationship between visual map intricacy, choice complexity, and informational performance, measured as behavioral consistency. We propose an IS research agenda to initiate a discussion about design of and human interaction with digital maps, their role for mobility IS, and for our field beyond

How are you Feeling? Inferring Emotions through Movements in the Metaverse

Metaverses are immersive virtual worlds in which people interact as avatars. There is emerging interest in understanding how metaverse users behave and perceive activities and tasks. Our understanding of users’ behavior within metaverses is limited. This study examines the role of emotions in the movement of individuals. We therefore implement a metaverse setting using virtual reality technology and development tools. In our study, we manipulated negative emotions and tracked the movements of our participants. We show how negative emotion influences movements in a metaverse setting. Based on a literature review, we select and calculate movement features to train a support vector machine. As our result, we present a novel way to infer the negative emotions of metaverse users which will help create more engaging and immersive experiences that cater to user’s emotions and behaviors. Our study provides preliminary evidence for the potential utilization of movement data in the metaverse

EXPLORING THREAT-SPECIFIC PRIVACY ASSURANCES IN THE CONTEXT OF CONNECTED VEHICLE APPLICATIONS

Connected vehicles enable a wide range of use cases, often facilitated by smartphone apps and involving extensive processing of driving-related data. Since information about actual driving behavior or even daily routines can be derived from this data, the question of privacy arises. We explore the impact of privacy assurances on driving data sharing concerns. Specifically, we consider two data-intensive cases: usage-based insurance and traffic hazard warning apps. We conducted two experimental comparisons to investigate whether and how privacy-related perceptions about vehicle data sharing can be altered by different types of text-based privacy assurances on fictional app store pages. Our results are largely inconclusive, and we did not find clear evidence that text-based privacy guarantees can significantly alter privacy concerns and download intentions. Our results suggest that general and threat-specific privacy assurance statements likely yield no or only negligible benefits for providers of connected vehicle apps regarding user perceptions

The Colors of Performance – Assessing the Impact of Color-Coding on Worker Behavior in Retail Order Picking

Advanced technologies are introduced in warehouse operations, rendering the interplay between human worker behavior and information systems (IS) a critical issue. We investigate how IS supports manual order picking by studying how visual color-coding information on picking locations provided through personal digital assistants accelerates search and picking tasks. Considering real-world data on a storage system where 20 dissimilar items are stored together at one picking location, we apply a log-logistic accelerated failure time model with N=112,672 picks performed by N=190 workers and find that color-coding accelerates the picking process by up to 17.28%. To increase the internal validity of our field-based examination, we conduct one VR experiment (N=29 participants) providing evidence for an acceleration of 23.74%, and one online experiment (N=178 participants) indicating an acceleration of 24.29%. Based on an innovative method of triangulation, we demonstrate how IS can influence picker behavior and discuss how to better design IT artifacts