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TeraByte InfraRed Delivery
NASA's Pathfinder Technology Demonstrator (PTD) Project is a series of tech demonstrations of technologies aboard a series of nanosatellites known as CubeSats, providing significant enhancements to the performance of these versatile spacecraft. Each of the five planned PTD missions consist of a 6-unit (6U) CubeSat with expandable solar arrays. Flight qualification and demonstration of these technologies carried aboard the PTD missions are expected to benefit future government and commercial missions. These include propulsion systems and sub-systems that stabilize and point the spacecraft to high accuracy in order to use a laser communications system capable of high-speed broadband. The first mission, PTD-1, was scheduled for launch in December 2020 on a Falcon 9 rocket, from Cape Canaveral, as part of the ride-share ELaNa mission 35, launched on January 24th, 2021, and demonstrated HYDROS-C water-based propellant system. PTD-3 launched on May 25 2022 on the SpaceX Transporte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Technology Demonstration
A technology demonstration (or tech demo), also known as demonstrator model, is a prototype, rough example or otherwise incomplete version of a conceivable product or future system, put together as proof of concept with the primary purpose of showcasing the possible applications, feasibility, performance and method of an idea for a new technology. They can be used as demonstrations to the investors, partners, journalists or even to potential customers in order to convince them of the viability of the chosen approach, or to test them on ordinary users. Computers and gaming Technology demonstrations are often used in the computer industry, emerging as an important tool in response to short development cycles in software and hardware development. * Computer game developers use tech demos to rouse and maintain interest to titles still in development (because game engines are usually ready before the art is finished) and to ensure functionality by early testing. Short segments using fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
California
California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an international border with the Mexico, Mexican state of Baja California to the south. With almost 40million residents across an area of , it is the List of states and territories of the United States by population, largest state by population and List of U.S. states and territories by area, third-largest by area. Prior to European colonization of the Americas, European colonization, California was one of the most culturally and linguistically diverse areas in pre-Columbian North America. European exploration in the 16th and 17th centuries led to the colonization by the Spanish Empire. The area became a part of Mexico in 1821, following Mexican War of Independence, its successful war for independence, but Mexican Cession, was ceded to the U ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sun Sensor
A Sun sensor is a navigational instrument used by spacecraft to detect the position of the Sun. Sun sensors are used for Spacecraft attitude control, attitude control, solar array pointing, gyroscope, gyro updating, and safe mode (spacecraft), fail-safe recovery. In addition to spacecraft, Sun sensors find use in ground-based weather stations and Sun-tracking systems, and aerial vehicles including Balloon (aeronautics), balloons and Unmanned aerial vehicle, UAVs. Mechanism There are various types of Sun sensors, which differ in their technology and performance characteristics. Sun presence sensors provide a binary number, binary output, indicating when the Sun is within the sensor's field of view. Analog electronics, Analog and digital electronics, digital Sun sensors, in contrast, indicate the angle of the Sun by continuous and discrete signal outputs, respectively. In typical Sun sensors, a thin slit at the top of a rectangular chamber allows a line of light to fall on an array ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inertial Measurement Unit
An inertial measurement unit (IMU) is an electronic device that measures and reports a body's specific force, angular rate, and sometimes the Orientation (geometry), orientation of the body, using a combination of accelerometers, gyroscopes, and sometimes magnetometers. When the magnetometer is included, IMUs are referred to as IMMUs. IMUs are typically used to maneuver modern vehicles including motorcycles, missiles, aircraft (an attitude and heading reference system), including uncrewed aerial vehicles (UAVs), among many others, and spacecraft, including satellites and Lander (spacecraft), landers. Recent developments allow for the production of IMU-enabled GPS devices. An IMU allows a GPS receiver to work when GPS-signals are unavailable, such as in tunnels, inside buildings, or when electronic interference is present. IMUs are used in VR headsets and smartphones, and also in motion tracked game controllers like the Wii Remote. Operational principles file:Centrale-intert ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetometer
A magnetometer is a device that measures magnetic field or magnetic dipole moment. Different types of magnetometers measure the direction, strength, or relative change of a magnetic field at a particular location. A compass is one such device, one that measures the direction of an ambient magnetic field, in this case, the Earth's magnetic field. Other magnetometers measure the magnetic dipole moment of a magnetic material such as a ferromagnet, for example by recording the effect of this magnetic dipole on the induced current in a coil. The invention of the magnetometer is usually credited to Carl Friedrich Gauss in 1832. Earlier, more primitive instruments were developed by Christopher Hansteen in 1819, and by William Scoresby by 1823. Magnetometers are widely used for measuring the Earth's magnetic field, in geophysical surveys, to detect magnetic anomalies of various types, and to determine the dipole moment of magnetic materials. In an aircraft's attitude and heading ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetorquer
A magnetorquer or magnetic torquer (also known as a torque rod) is a satellite system for Spacecraft attitude control, attitude control, detumbling, and stabilization built from electromagnetic coils. The magnetorquer creates a magnetic dipole that interfaces with an ambient magnetic field, usually Earth's magnetic field, Earth's, so that the counter-forces produced provide useful torque. Functional principle Magnetorquers are sets of electromagnets arranged to yield a rotationally asymmetric (anisotropic) magnetic field over an extended area. That field is controlled by switching Electric current, current flow through the coils on or off, usually under computerized feedback control theory, control. The magnets themselves are mechanically anchored to the craft, so that any magnetic force they exert on the surrounding magnetic field will lead to a magnetic reverse force and result in mechanical torque about the vessel's center of gravity. This makes it possible to freely pivot the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reaction Wheels
A reaction wheel (RW) is an electric motor attached to a flywheel, which, when its rotation speed is changed, causes a counter-rotation proportionately through conservation of angular momentum. A reaction wheel can rotate only around its center of mass; it is not capable of moving from one place to another ( translational force). Reaction wheels are used primarily by spacecraft for three-axis attitude control, and do not require rockets or external applicators of torque, which reduces the mass fraction needed for fuel. They provide a high pointing accuracy, and are particularly useful when the spacecraft must be rotated by very small amounts, such as keeping a telescope pointed at a star. A reaction wheel is sometimes operated at a constant (or near-constant) rotation speed, to provide a satellite with a large amount of stored angular momentum. Doing so alters the spacecraft's rotational dynamics so that disturbance torques perpendicular to one axis of the satellite (the axis p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Star Tracker
A star tracker is an optical device that measures the positions of stars using photocells or a camera. As the positions of many stars have been measured by astronomers to a high degree of accuracy, a star tracker on a satellite or spacecraft may be used to determine the orientation (or attitude) of the spacecraft with respect to the stars. In order to do this, the star tracker must obtain an image of the stars, measure their apparent position in the reference frame of the spacecraft, and identify the stars so their position can be compared with their known absolute position from a star catalog. A star tracker may include a processor to identify stars by comparing the pattern of observed stars with the known pattern of stars in the sky. History In the 1950s and early 1960s, star trackers were an important part of early long-range ballistic missiles and cruise missiles, in the era when inertial navigation systems (INS) were not sufficiently accurate for intercontinental ranges. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LISA Pathfinder
LISA Pathfinder, formerly Small Missions for Advanced Research in Technology-2 (SMART-2), was an ESA spacecraft that was launched on 3 December 2015 on board Vega flight VV06. The mission tested technologies needed for the Laser Interferometer Space Antenna (LISA), an ESA gravitational wave observatory planned to be launched in 2035. The scientific phase started on 8 March 2016 and lasted almost sixteen months. In April 2016 ESA announced that LISA Pathfinder demonstrated that the LISA mission is feasible. The estimated mission cost was €400 million. Mission LISA Pathfinder placed two test masses in a nearly perfect gravitational free-fall, and controlled and measured their relative motion with unprecedented accuracy. The laser interferometer measured the relative position and orientation of the masses to an accuracy of less than 0.01 nanometres, a technology estimated to be sensitive enough to detect gravitational waves by the follow-on mission, the Laser Interferomete ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Busek
Busek Company Incorporated is an American spacecraft propulsion company that builds thrusters, electronics, and various systems for spacecraft. History Busek was founded in 1985 by Vlad Hruby in Natick, Massachusetts. Busek started as a laboratory outside of Boston, Massachusetts. Flight missions TacSat-2 The first US Hall thruster flown in space, Busek's BHT-200, was launched aboard the Air Force Research Laboratory's (AFRL) TacSat-2 satellite. The Busek thruster was part of the Microsatellite Propulsion Integration (MPI) Experiment and was integrated on TacSat-2 under the direction of the DoD Space Test Program. TacSat-2 launched on December 16, 2006 from the NASA Wallops Flight Facility. LISA Pathfinder The first electrospray thruster that made it to space was manufactured by Busek and launched aboard the European Space Agency's LISA Pathfinder satellite on December 3, 2015. The micro-newton colloid-style electric thruster was developed under contract with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colloid Thruster
A colloid is a mixture in which one substance consisting of microscopically Dispersion (chemistry), dispersed insoluble particles is suspension (chemistry), suspended throughout another substance. Some definitions specify that the particles must be dispersed in a liquid, while others extend the definition to include substances like aerosols and gels. The term colloidal suspension refers unambiguously to the overall mixture (although a narrower sense of the word ''suspension (chemistry), suspension'' is distinguished from colloids by larger particle size). A colloid has a dispersed phase (the suspended particles) and a continuous phase (the medium of suspension). The dispersed phase particles have a diameter of approximately 1 nanometre to 1 micrometre. Some colloids are translucent because of the Tyndall effect, which is the scattering of light by particles in the colloid. Other colloids may be Opacity (optics), opaque or have a slight color. Colloidal suspensions are the subjec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spacecraft Attitude Control
Spacecraft attitude control is the process of controlling the orientation of a spacecraft (vehicle or satellite) with respect to an inertial frame of reference or another entity such as the celestial sphere, certain fields, and nearby objects, etc. Controlling vehicle attitude requires actuators to apply the torques needed to orient the vehicle to a desired attitude, and algorithms to command the actuators based on the current attitude and specification of a desired attitude. Before and during attitude control can be performed, spacecraft attitude determination must be performed, which requires sensors for absolute or relative measurement. The broader integrated field that studies the combination of sensors, actuators and algorithms is called ''guidance, navigation and control'', which also involves non-attitude concepts, such as position determination and navigation. Motivation A spacecraft's attitude must typically be stabilized and controlled for a variety of reasons. It ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
