Quantum compass

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The terminology quantum compass often relates to an instrument which measures relative position using the technique of atom interferometry. It includes an ensemble of accelerometers and gyroscope based on quantum technology [1] to form an Inertial Navigation Unit.

Description

Work on quantum technology based inertial measurement units (IMUs), the instruments containing the gyroscopes and accelerometers, follows from early demonstrations of matter-wave based accelerometers and gyrometers. [2] The first demonstration of onboard acceleration measurement was made on an Airbus A300 in 2011. [3]

A quantum compass contains clouds of atoms frozen using lasers. By measuring the movement of these frozen particles over precise periods of time the motion of the device can be calculated. The device would then provide accurate position in circumstances where satellites are not available for satellite navigation, e.g. a fully submerged submarine. [4]

Various defence agencies worldwide, such as the US DARPA [5] and the United Kingdom Ministry of Defence [6] [4] have pushed the development of prototypes for future uses in submarines and aircraft.

In 2024, researchers from the Centre for Cold Matter of Imperial College, London, tested an experimental quantum compass on an underground train on London's District line. [7]

Related Research Articles

<span class="mw-page-title-main">Navigation</span> Process of monitoring and controlling the movement of a craft or vehicle from one place to another

Navigation is a field of study that focuses on the process of monitoring and controlling the movement of a craft or vehicle from one place to another. The field of navigation includes four general categories: land navigation, marine navigation, aeronautic navigation, and space navigation.

<span class="mw-page-title-main">Gyroscope</span> Device for measuring or maintaining the orientation and angular velocity

A gyroscope is a device used for measuring or maintaining orientation and angular velocity. It is a spinning wheel or disc in which the axis of rotation is free to assume any orientation by itself. When rotating, the orientation of this axis is unaffected by tilting or rotation of the mounting, according to the conservation of angular momentum.

<span class="mw-page-title-main">Magnetometer</span> Device that measures magnetism

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.

<span class="mw-page-title-main">Accelerometer</span> Device that measures proper acceleration

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<span class="mw-page-title-main">Gravimetry</span> Measurement of the strength of a gravitational field

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<span class="mw-page-title-main">Fibre-optic gyroscope</span> Gyroscope that uses fiber optics

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<span class="mw-page-title-main">Inertial navigation system</span> Continuously computed dead reckoning

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<span class="mw-page-title-main">LN-3 inertial navigation system</span>

The LN-3 inertial navigation system is an inertial navigation system (INS) that was developed in the 1960s by Litton Industries. It equipped the Lockheed F-104 Starfighter versions used as strike aircraft in European forces. An inertial navigation system is a system which continually determines the position of a vehicle from measurements made entirely within the vehicle using sensitive instruments. These instruments are accelerometers which detect and measure vehicle accelerations, and gyroscopes which act to hold the accelerometers in proper orientation.

<span class="mw-page-title-main">Inertial measurement unit</span> Accelerometer-based navigational device

An inertial measurement unit (IMU) is an electronic device that measures and reports a body's specific force, angular rate, and sometimes the orientation of the body, using a combination of accelerometers, gyroscopes, and sometimes magnetometers. When the magnetometer is included, IMUs are referred to as IMMUs.

Sensors able to detect three-dimensional motion have been commercially available for several decades and have been used in automobiles, aircraft and ships. However, initial size, power consumption and price had prevented their mass adoption in consumer electronics. While there are other kinds of motion detector technologies available commercially, there are four principle types of motion sensors which are important for motion processing in the consumer electronics market.

<span class="mw-page-title-main">Pressure reference system</span> Flight instrument

Pressure reference system (PRS) is an enhancement of the inertial reference system and attitude and heading reference system designed to provide position angles measurements which are stable in time and do not suffer from long term drift caused by the sensor imperfections. The measurement system uses behavior of the International Standard Atmosphere where atmospheric pressure descends with increasing altitude and two pairs of measurement units. Each pair measures pressure at two different positions that are mechanically connected with known distance between units, e.g. the units are mounted at the tips of the wing. In horizontal flight, there is no pressure difference measured by the measurement system which means the position angle is zero. In case the airplane banks (to turn), the tips of the wings mutually change their positions, one is going up and the second one is going down, and the pressure sensors in every unit measure different values which are translated into a position angle.

<span class="mw-page-title-main">Hemispherical resonator gyroscope</span> Type of gyroscope

The hemispherical resonator gyroscope (HRG), also called wine-glass gyroscope or mushroom gyro, is a compact, low-noise, high-performance angular rate or rotation sensor. An HRG is made using a thin solid-state hemispherical shell, anchored by a thick stem. This shell is driven to a flexural resonance by electrostatic forces generated by electrodes which are deposited directly onto separate fused-quartz structures that surround the shell. The gyroscopic effect is obtained from the inertial property of the flexural standing waves. Although the HRG is a mechanical system, it has no moving parts, and can be very compact.

References

  1. Chen, Sophia (2018). "Quantum Physicists Found a New, Safer Way to Navigate". Wired.
  2. Kasevich, Mark (2012). "Precision Navigation Sensors based on Atom Interferometry" (PDF). Stanford Center for Position, Navigation and Time.
  3. Dillow, Clay. "For the First Time, Researchers Use an Atom Interferometer to Measure Aircraft Acceleration". Popular Science. Retrieved September 29, 2011.
  4. 1 2 "Quantum positioning system steps in when GPS fails". New Scientist . 14 May 2014. Retrieved 18 May 2014.
  5. Kramer, David (2014-09-30). "DARPA looks beyond GPS for positioning, navigating, and timing". Physics Today. 67 (10): 23–26. Bibcode:2014PhT....67j..23K. doi: 10.1063/PT.3.2543 . ISSN   0031-9228.
  6. "MoD creates 'coldest object in the universe' to trump GPS". The Daily Telegraph . 18 May 2014. Retrieved 18 May 2014.
  7. McKie, Robin (15 June 2024). "'It's the perfect place': London Underground hosts tests for 'quantum compass' that could replace GPS". The Guardian. London.