175 research outputs found
Ultra-Lightweight Deployable Antenna Membrane Technology for Future Non-terrestrial 6G Network and Earth Observation
A deployable antenna membrane is one of the promising solutions to achieve a higher speed of satellite communication and earth observation in small satellites. Unlike conventional deployable antennas, the proposed approach permits low flatness of the antenna membrane and compensates it electrically. By eliminating the conventional large deployment and support structure, the proposed non-planar membrane can be lighter and installed in small satellites. We introduce two types of membrane antennas: reflectarray antennas and active phased-array transceivers
Implementation of Satellite Formation Flight Algorithms Using SPHERES Aboard the International Space Station
The MIT's Space Systems Laboratory developed the Synchronized Position Hold Engage and Reorient Experimental Satellites (SPHERES) as a risk-tolerant spaceborne facility to develop and mature control, estimation, and autonomy algorithms for distributed satellite systems for applications such as satellite formation flight. Tests performed study interferometric mission-type formation flight maneuvers in deep space. These tests consist of having the satellites trace a coordinated trajectory under tight control that would allow simulated apertures to constructively interfere observed light and measure the resulting increase in angular resolution. This paper focuses on formation initialization (establishment of a formation using limited field of view relative sensors), formation coordination (synchronization of the different satellite s motion) and fuel-balancing among the different satellites
Conceptual model study using origami for membrane space structures : a perspective of origami-based engineering
This paper discusses what has been found and what will be found using conceptual “origami” models to develop deployable space structures. The study covers the following: (i) one-dimensional structural elements, which are axially buckled inflatable tubes; (ii) two-dimensional elements, which are deployable membranes, such as solar arrays and solar sails; and (iii) deployable elements in nature. The study clarifies what design considerations are necessary to adapt the basic concepts to actual space structural hardware, and several limitations of origami models are discussed. Regarding the last subject, this study envisions future space structures using conceptual origami models that imitate three-dimensional deployable structures in nature, such as flowers and insect wings
Verification of Tether Deployment System aboard CubeSat through Dynamics Simulations and Tests
This paper proposes a proper model selection strategies for the dynamic simulations of the tether deployment mission aboard a CubeSat. Space tether technology will enable innovative space missions in the near future. The Coulomb Drag Propulsion (CDP), including electric solar wind sailing, is one of the plausible future technologies. The authors currently develop a CubeSat, FORESAIL-1, for space demonstration of CDP. However, the analytical simulations for the verification and validation of the mission design typically require a high computational cost. This is because a minimum model order is not selected properly. In this study, through observing a preliminary analytical model for tether deployment analysis, the simplest model is chosen to avoid the mission failure modes in each deployment phase.Peer reviewe
On-Orbit Demonstration of Innovative Multifunctional Membrane Structure for Ultra-Lightweight Solar Arrays and Array Antennas by 3U CubeSat OrigamiSat-1
The 3U CubeSat OrigamiSat-1’s deployable membrane structure is 1m-by-1m in size after deployment and is stowed in less than 1U CubeSat (10cm-by-10cm-by-8cm), including a hold-and-release mechanism. The major significance of the structural concept is that it allows the attachment of thin-film devices, such as thin-film solar cells or flexible substrates for antennas throughout the membrane. This was achieved by two features: (i) use of textile and (ii) invention of hybrid boom made of tubular carbon composite and metal convex tape. In addition, a visual membrane measurement system consisting of stereo cameras was developed. This paper describes the new technologies developed for this CubeSat
Two-Layer Pop-Up Origami Deployable Membrance Reflectarray Antenna Stowed in 1U CubeSat
The present paper shows the innovative deployable reflectarray antenna concept that enables to stow a 1m-by-1m square antenna into 1U CubeSat volume. The antenna is composed of two-layer membranes to obtain an air gap. A one-layer deployable membrane structure was demonstrated by the 3U CubeSat OrigamiSat-1 in 2019. The authors are currently developing two technologies to realize the reflectarray antenna. First, the deployable two-layer membrane structure is to be achieved by using pop-up picture book’s mechanism. Second, reflection elements for the reflectarray antenna that do not cross folding lines are proposed to avoid gain degradation
Space Demonstration of Two-Layer Pop-Up Origami Deployable Membrane Reflectarray Antenna by 3U CubeSat OrigamiSat-2
3U CubeSat OrigamiSat-2 demonstrates a 50-cm × 50-cm two-layer pop-up Origami deployable membrane reflectarray antenna in space. The membrane has small stowage volume and high gain even though it has low flatness because of a large enough antenna area to cover its un-flatness. C-band transmitter is equipped in the CubeSat and offers 20-Mbps amateur satellite communication. In 3U size, a 1-m length deployable gravity gradient mast and magnetic torquer are equipped to stabilize and control its attitude. A camera is attached to the satellite to measure the shape of the membrane antenna. OrigamiSat-2 was selected as the Innovative Satellite Technology Demonstration-4 by Japan Aerospace Exploration Agency (JAXA) and is going to be launched in 2024 by Epsilon Launch Vehicle
Development of a Multifunctional Lightweight Membrane with a High Specific Power Generation Capacity
As a lighter power generation system, Japan Aerospace Exploration Agency (JAXA) and Sakase Adtech Corp. are developing a demonstrator component named “Harvesting Energy with Lightweight Integrated Origami Structure” (HELIOS), which is a deployable lightweight membrane structure. HELIOS has solar arrays on its surface and demonstrates the technology which enables higher specific power generation capacity compared to the conventional solar array panels. The membrane also has communication antennas, showing the potency of lightweight membrane’s multifunctionality such as large data transmitting by 5G antennas and high-resolution observation by interferometer antennas. This paper presents the component’s concept and design, and the expected achievements
ARHGEF15 overexpression worsens the prognosis in patients with pancreatic ductal adenocarcinoma through enhancing the motility and proliferative activity of the cancer cells
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