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75-434: The turn and slip indicator can be referred to as the turn and bank indicator, although the instrument does not respond directly to bank angle. Neither does the turn coordinator, but it does respond to roll rate, which enables it to respond more quickly to the start of a turn. The turn indicator is a gyroscopic instrument that works on the principle of precession . The gyro is mounted in a gimbal . The gyro's rotational axis

150-481: A damper , is a mechanical device that resists motion via viscous friction . The resulting force is proportional to the velocity , but acts in the opposite direction, slowing the motion and absorbing energy. It is commonly used in conjunction with a spring . The process and instrumentation diagram (P&ID) symbol for a dashpot is [REDACTED] . The two most common types of dashpots are linear and rotary. Linear dashpots — or linear dampers — are used to exert

225-458: A coil of fiber optic cable as long as 5 km. Like the ring laser gyroscope , it makes use of the Sagnac effect . A London moment gyroscope relies on the quantum-mechanical phenomenon, whereby a spinning superconductor generates a magnetic field whose axis lines up exactly with the spin axis of the gyroscopic rotor. A magnetometer determines the orientation of the generated field, which

300-403: A fluid, instead of being mounted in gimbals. A control moment gyroscope (CMG) is an example of a fixed-output-gimbal device that is used on spacecraft to hold or maintain a desired attitude angle or pointing direction using the gyroscopic resistance force. In some special cases, the outer gimbal (or its equivalent) may be omitted so that the rotor has only two degrees of freedom. In other cases,

375-422: A force applied to the input axis by a reaction force to the output axis. A gyroscope flywheel will roll or resist about the output axis depending upon whether the output gimbals are of a free or fixed configuration. An example of some free-output-gimbal devices is the attitude control gyroscopes used to sense or measure the pitch, roll and yaw attitude angles in a spacecraft or aircraft. The centre of gravity of

450-465: A force opposite to a translation movement. They are generally specified by stroke (amount of linear displacement) and damping coefficient (force per velocity). Similarly, rotary dampers will tend to oppose any torque applied to them, in an amount proportional to their rotational speed. Their damping coefficients will usually be specified by torque per angular velocity. One can distinguish two kinds of viscous rotary dashpots: A less common type of dashpot

525-463: A gyroscope (the "Whirling Speculum" or "Serson's Speculum") was invented by John Serson in 1743. It was used as a level, to locate the horizon in foggy or misty conditions. The first instrument used more like an actual gyroscope was made by Johann Bohnenberger of Germany, who first wrote about it in 1817. At first he called it the "Machine". Bohnenberger's machine was based on a rotating massive sphere. In 1832, American Walter R. Johnson developed

600-421: A gyroscope with a weight on one of the axes. The device will react to the force generated by the weight when it is accelerated, by integrating that force to produce a velocity. A gyrostat consists of a massive flywheel concealed in a solid casing. Its behaviour on a table, or with various modes of suspension or support, serves to illustrate the curious reversal of the ordinary laws of static equilibrium due to

675-411: A gyroscope with two gimbals, the outer gimbal, which is the gyroscope frame, is mounted so as to pivot about an axis in its own plane determined by the support. This outer gimbal possesses one degree of rotational freedom and its axis possesses none. The second gimbal, inner gimbal, is mounted in the gyroscope frame (outer gimbal) so as to pivot about an axis in its own plane that is always perpendicular to

750-404: A human hair viewed from 32 kilometers (20 mi) away. The GP-B gyro consists of a nearly-perfect spherical rotating mass made of fused quartz , which provides a dielectric support for a thin layer of niobium superconducting material. To eliminate friction found in conventional bearings, the rotor assembly is centered by the electric field from six electrodes. After the initial spin-up by

825-471: A jet of helium which brings the rotor to 4,000 RPM , the polished gyroscope housing is evacuated to an ultra-high vacuum to further reduce drag on the rotor. Provided the suspension electronics remain powered, the extreme rotational symmetry , lack of friction, and low drag will allow the angular momentum of the rotor to keep it spinning for about 15,000 years. A sensitive DC SQUID that can discriminate changes as small as one quantum, or about 2 × 10 Wb ,

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900-410: A liquid to act as a damping medium. The original form of the indicator is in effect a spirit level with the tube curved in the opposite direction and a bubble standing in for the ball. In some early aircraft the indicator was merely a pendulum with a dashpot for damping. The ball gives an indication of whether the aircraft is slipping, skidding or in coordinated flight. The ball's movement is caused by

975-631: A magnetic compass, it does not seek north. When being used in an airplane, for example, it will slowly drift away from north and will need to be reoriented periodically, using a magnetic compass as a reference. Unlike a directional gyro or heading indicator, a gyrocompass seeks north. It detects the rotation of the Earth about its axis and seeks the true north, rather than the magnetic north. Gyrocompasses usually have built-in damping to prevent overshoot when re-calibrating from sudden movement. By determining an object's acceleration and integrating over time,

1050-457: A one-way mechanical bypass to permit fast unrestricted motion in one direction and slow motion using the dashpot in the opposite direction. This permits, for example, a door to be opened quickly without added resistance, but then to close slowly using the dashpot. For hydraulic dashpots this unrestricted motion is accomplished using a one-way check-valve that allows fluid to bypass the dashpot fluid constriction. Non-hydraulic rotatory dashpots may use

1125-424: A pilot to perform timed turns in order to conform with the required air traffic patterns. For a change of heading of 90 degrees, a turn lasting 30 seconds would be required to perform a standard rate or "rate one" turn. Coordinated flight indication is obtained by using an inclinometer , which is recognized as the "ball in a tube". An inclinometer contains a ball sealed inside a curved glass tube, which also contains

1200-440: A position between the low-accuracy, low-cost MEMS gyroscope and the higher-accuracy and higher-cost fiber optic gyroscope. Accuracy parameters are increased by using low-intrinsic damping materials, resonator vacuumization, and digital electronics to reduce temperature dependent drift and instability of control signals. High quality wine-glass resonators are used for precise sensors like HRG. A dynamically tuned gyroscope (DTG)

1275-446: A ratcheting gear to permit free motion in one direction. Dashpots are frequently used to add damping to dynamic systems . When designing and analyzing systems, dashpots are often assumed to be linear, meaning that their output force is linearly proportional to their velocity. F = − c v {\displaystyle F=-cv} This permits convenient analysis of systems such as harmonic oscillators . However,

1350-501: A similar device that was based on a rotating disc. The French mathematician Pierre-Simon Laplace , working at the École Polytechnique in Paris, recommended the machine for use as a teaching aid, and thus it came to the attention of Léon Foucault . In 1852, Foucault used it in an experiment demonstrating the rotation of the Earth. It was Foucault who gave the device its modern name, in an experiment to see (Greek skopeein , to see)

1425-407: A single integrated circuit package, providing inexpensive and widely available motion sensing. All spinning objects have gyroscopic properties. The main properties that an object can experience in any gyroscopic motion are rigidity in space and precession . Rigidity in space describes the principle that a gyroscope remains in the fixed position on the plane in which it is spinning, unaffected by

1500-591: A slip is used as a forward slip and a sideslip . These slips are performed by applying opposite inputs of the aileron and rudder controls. A forward slip allows a pilot to quickly drop altitude without gaining unnecessary speed, while a sideslip is one method utilized to perform a crosswind landing . Although the Turn and Slip Indicator (and later the Turn Coordinator) was felt to be a necessary and required instrument for flight under instrument flight rules ,

1575-570: A speed of 24,000 revolutions per minute in less than 10 seconds. Gyroscopes continue to be an engineering challenge. For example, the axle bearings have to be extremely accurate. A small amount of friction is deliberately introduced to the bearings, since otherwise an accuracy of better than 10 − 7 {\displaystyle 10^{-7}} of an inch (2.5 nm) would be required. Three-axis MEMS-based gyroscopes are also used in portable electronic devices such as tablets , smartphones , and smartwatches . This adds to

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1650-439: A standard rate or two-minute turn, and "4 min turn" for those, used in faster aircraft, that show a half standard rate or four-minute turn. The supersonic Concorde jet aircraft and many military jets are examples of aircraft that use 4 min. turn indicators. The hash marks are sometimes called "dog houses", because of their distinct shape on various makes of turn indicators. Under instrument flight rules , using these figures allows

1725-411: A stepped needle. This needle is held in the fuel flow orifice. The manifold vacuum causes this piston to rise allowing more fuel into the airflow. The SU's dashpot has a fixed hydraulic piston, damping the main piston as it moves upward. A valve in the piston disables the damping as the main piston returns. Large forces and high speeds can be controlled by dashpots. For example, they are used to arrest

1800-443: 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. Gyroscopic effect is obtained from the inertial property of the flexural standing waves. A vibrating structure gyroscope (VSG), also called a Coriolis vibratory gyroscope (CVG), uses a resonator made of different metallic alloys. It takes

1875-405: A toy gyroscope with a pull string and pedestal. Manufacture was at some point switched to Chandler Mfg Co (still branded Hurst). The product was later renamed to a “Chandler gyroscope”, presumably because Chandler Mfg Co. took over rights to the gyroscope. Chandler continued to produce the toy until the company was purchased by TEDCO Inc. in 1982. The gyroscope is still produced by TEDCO today. In

1950-464: Is interpolated to determine the axis of rotation. Gyroscopes of this type can be extremely accurate and stable. For example, those used in the Gravity Probe B experiment measured changes in gyroscope spin axis orientation to better than 0.5 milliarcseconds (1.4 × 10 degrees, or about 2.4 × 10  radians ) over a one-year period. This is equivalent to an angular separation the width of

2025-448: Is a yaw string , which allows the pilot to simply view the string's movements as rudimentary indication of aircraft balance. The turn coordinator (TC) is a further development of the turn and slip indicator (T/S) with the major difference being the display and the axis upon which the gimbal is mounted. The display is that of a miniature airplane as seen from behind. This looks similar to that of an attitude indicator. "NO PITCH INFORMATION"

2100-411: Is a common component in a door closer to prevent it from slamming shut. A spring applies force to close the door, which the dashpot offsets by forcing fluid to flow through an orifice, often adjustable, between reservoirs, which slows the motion of the door. Consumer electronics often use dashpots where it is undesirable for a media access door or control panel to suddenly pop open when the door latch

2175-476: Is a miniaturized gyroscope found in electronic devices. It takes the idea of the Foucault pendulum and uses a vibrating element. This kind of gyroscope was first used in military applications but has since been adopted for increasing commercial use. The hemispherical resonator gyroscope (HRG), also called a wine-glass gyroscope or mushroom gyro, makes use of a thin solid-state hemispherical shell, anchored by

2250-426: Is a rotor suspended by a universal joint with flexure pivots. The flexure spring stiffness is independent of spin rate. However, the dynamic inertia (from the gyroscopic reaction effect) from the gimbal provides negative spring stiffness proportional to the square of the spin speed (Howe and Savet, 1964; Lawrence, 1998). Therefore, at a particular speed, called the tuning speed, the two moments cancel each other, freeing

2325-493: Is a spinning wheel or disc in which the axis of rotation (spin axis) 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 . Gyroscopes based on other operating principles also exist, such as the microchip-packaged MEMS gyroscopes found in electronic devices (sometimes called gyrometers ), solid-state ring lasers , fibre optic gyroscopes , and

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2400-411: Is also impaired if the internal dashpot is worn out. In the latter case, the instrument is underdamped and in turbulence will indicate large full-scale deflections to the left and right, all of which are actually roll rate responses. Slipping and skidding within a turn is sometimes referred to as a sloppy turn, due to the perceptive discomfort it can cause to the pilot and passengers. When the aircraft

2475-435: Is an eddy current damper, which uses a large magnet inside a tube constructed of a non-magnetic but conducting material (such as aluminium or copper ). Like a common viscous damper, the eddy current damper produces a resistive force proportional to velocity. A common use of the eddy current damper is in balance scales. This is a frictionless method that allows the scale to quickly come to rest. Dashpots frequently use

2550-403: Is an instrument, consisting of a wheel mounted into two or three gimbals providing pivoted supports, for allowing the wheel to rotate about a single axis. A set of three gimbals, one mounted on the other with orthogonal pivot axes, may be used to allow a wheel mounted on the innermost gimbal to have an orientation remaining independent of the orientation, in space, of its support. In the case of

2625-427: Is designed to minimize Lorentz torque on the rotor. The main rotor of a helicopter acts like a gyroscope. Its motion is influenced by the principle of gyroscopic precession which is the concept that a force applied to a spinning object will have a maximum reaction approximately 90 degrees later. The reaction may differ from 90 degrees when other stronger forces are in play. To change direction, helicopters must adjust

2700-720: Is for delaying the closing or opening of an electrical circuit. Such a dashpot timer might be used for example for timed staircase lighting. Anti-stall mechanisms in internal combustion engines are aimed to prevent stalling of the engine at low rpm. Anti-stall mechanisms use dashpots to arrest the final closing movement of the throttle. Large dashpots are added to bridges and buildings to protect against earthquakes and wind vibrations. Dashpots are used as models of materials that exhibit viscoelastic behavior, such as muscle tissue. Maxwell and Kelvin–Voigt models of viscoelasticity use springs and dashpots in series and parallel circuits respectively. Models containing dashpots add

2775-472: Is in a balanced turn (ball is centered), passengers experience gravity directly in line with their seat (force perpendicular to seat). With a well balanced turn, passengers may not even realize the aircraft is turning unless they are viewing objects outside the aircraft. While aircraft slipping and skidding are often undesired in a usual turn that maintains altitude, slipping of the aircraft can be used for practical purposes. Intentionally putting an aircraft into

2850-448: Is in-line with the lateral (pitch) axis of the aircraft, while the gimbal has limited freedom around the longitudinal (roll) axis of the aircraft. As the aircraft yaws , a torque force is applied to the gyro around the vertical axis, due to aircraft yaw, which causes gyro precession around the roll axis. The gyro spins on an axis that is 90 degrees relative to the direction of the applied yaw torque force. The gyro and gimbal rotate (around

2925-454: Is no longer as useful as an instrument which gives both horizontal and vertical attitude information." Thus one can now legally replace a Turn-and-Slip or Turn Coordinator instrument with a second attitude indicator, preferably driven by a system different from the primary flight display. So if the aircraft primary display is vacuum powered, the second attitude indicator should be electric, and vice-versa. This gives more flight information than

3000-468: Is released. The dashpot provides a steady, gentle motion until the access door has fully opened. Dashpots are commonly used in dampers and shock absorbers . The hydraulic cylinder in an automobile shock absorber is a dashpot. They are also used on carburetors , where the return of the throttle lever is cushioned just before the throttle fully closes, then is allowed to fully close slowly to reduce emissions. The British SU carburettor 's main piston carries

3075-527: Is represented by spin, θ {\displaystyle \theta } is the nutation angle, and I {\displaystyle I} represents inertia along its respective axis. This relation is only valid with the Moment along the Y and Z axes are equal to 0. The equation can be further reduced noting that the angular velocity along the z-axis is equal to the sum of the Precession and

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3150-485: Is the rate of change of the angular momentum that is produced by the applied torque. Precession produces counterintuitive dynamic results such as a spinning top not falling over. Precession is used in aerospace applications for sensing changes of attitude and direction. A Steadicam rig was employed during the filming of the 1983 film Return of the Jedi , in conjunction with two gyroscopes for extra stabilization, to film

3225-469: Is used to monitor the gyroscope. A precession , or tilt, in the orientation of the rotor causes the London moment magnetic field to shift relative to the housing. The moving field passes through a superconducting pickup loop fixed to the housing, inducing a small electric current. The current produces a voltage across a shunt resistance, which is resolved to spherical coordinates by a microprocessor. The system

3300-507: Is usually written on the instrument to avoid confusion regarding the aircraft's pitch, which can be obtained from the artificial horizon instrument. In contrast to the T/S, the TC's gimbal is pitched up 30 degrees from the transverse axis. This causes the instrument to respond to roll as well as yaw. This allows the instrument to display a change more quickly as it will react to the change in roll before

3375-637: The Federal Aviation Administration (FAA) has more recently decided that these instruments are obsolete in today's flight environment. Advisory Circular No. 91-75, issued on 6/25/2003, states the following: [section 5 b] "...in today's air traffic control system, there is little need for precisely measured standard rate turns or timed turns based on standard rate." The Advisory Circular further states: "...the FAA believes, and all other commenters apparently agree...the rate-of-turn indicator

3450-431: The steam catapults on aircraft carrier decks. Relays can be made to have a long delay by utilizing a piston filled with fluid that is allowed to escape slowly. Electrical switchgear may use dashpots in their overcurrent sensing mechanism to reduce reaction speed to brief events, thus making them less sensitive to false-triggering during transients whilst still remaining sensitive to sustained overloads. Another use

3525-508: The 3-axis acceleration sensing ability available on previous generations of devices. Together these sensors provide 6 component motion sensing; accelerometers for X, Y, and Z movement, and gyroscopes for measuring the extent and rate of rotation in space (roll, pitch and yaw). Some devices additionally incorporate a magnetometer to provide absolute angular measurements relative to the Earth's magnetic field. Newer MEMS-based inertial measurement units incorporate up to all nine axes of sensing in

3600-559: The Earth's rotation (Greek gyros , circle or rotation), which was visible in the 8 to 10 minutes before friction slowed the spinning rotor. In the 1860s, the advent of electric motors made it possible for a gyroscope to spin indefinitely; this led to the first prototype heading indicators , and a rather more complicated device, the gyrocompass . The first functional gyrocompass was patented in 1904 by German inventor Hermann Anschütz-Kaempfe . American Elmer Sperry followed with his own design later that year, and other nations soon realized

3675-436: The Earth's rotation. For example, a bike wheel. Early forms of gyroscope (not then known by the name) were used to demonstrate the principle. A simple case of precession, also known as steady precession, can be described by the following relation to Moment: where ϕ ′ {\displaystyle \phi '} represents precession, ψ ′ {\displaystyle \psi '}

3750-451: The Spin: ω z = ϕ ′ cos ⁡ θ + ψ ′ {\displaystyle \omega _{z}=\phi '\cos \theta +\psi '} , Where ω z {\displaystyle \omega _{z}} represents the angular velocity along the z axis. or Gyroscopic precession is torque induced. It

3825-455: The aircraft has even begun to yaw. Although this instrument reacts to changes in the aircraft's roll, it does not display the roll attitude. The turn coordinator may be used as a performance instrument when the attitude indicator has failed. This is called "partial panel" operations. It can be unnecessarily difficult or even impossible if the pilot does not understand that the instrument is showing roll rates as well as turn rates. The usefulness

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3900-411: The background plates for the speeder bike chase. Steadicam inventor Garrett Brown operated the shot, walking through a redwood forest, running the camera at one frame per second. When projected at 24 frames per second, it gave the impression of flying through the air at perilous speeds. The heading indicator or directional gyro has an axis of rotation that is set horizontally, pointing north. Unlike

3975-512: The behavior of real-world dashpots is frequently non-linear, meaning that the force is proportional to the velocity raised to some exponent α {\displaystyle \alpha } , which can vary between 0.2 and 2. F = − c v α {\displaystyle F=-cv^{\alpha }} Different exponents are better suited for different applications, but exponents other than 1.0 must be analyzed with numeric methods instead of calculus. A dashpot

4050-440: The centre of gravity of the rotor may be offset from the axis of oscillation, and thus the centre of gravity of the rotor and the centre of suspension of the rotor may not coincide. Essentially, a gyroscope is a top combined with a pair of gimbals . Tops were invented in many different civilizations, including classical Greece, Rome, and China. Most of these were not utilized as instruments. The first known apparatus similar to

4125-434: The device was at rest at the extremities of its shaking motion. This was cured by applying a random white noise to the vibration. The material of the block was also changed from quartz to a new glass ceramic Cer-Vit , made by Owens Corning , because of helium leaks. A fiber optic gyroscope also uses the interference of light to detect mechanical rotation. The two-halves of the split beam travel in opposite directions in

4200-524: The equations of motion of a gyrostat. Examples include a solid body with a cavity filled with an inviscid, incompressible, homogeneous liquid, the static equilibrium configuration of a stressed elastic rod in elastica theory , the polarization dynamics of a light pulse propagating through a nonlinear medium, the Lorenz system in chaos theory, and the motion of an ion in a Penning trap mass spectrometer. A microelectromechanical systems (MEMS) gyroscope

4275-436: The ether. In modern continuum mechanics there is a variety of these models, based on ideas of Lord Kelvin. They represent a specific type of Cosserat theories (suggested for the first time by Eugène Cosserat and François Cosserat ), which can be used for description of artificially made smart materials as well as of other complex media. One of them, so-called Kelvin's medium, has the same equations as magnetic insulators near

4350-488: The experimental models went through many changes before it was deemed ready for production by the engineers and managers of Honeywell and Boeing . It was an outcome of the competition with mechanical gyroscopes, which kept improving. The reason Honeywell, of all companies, chose to develop the laser gyro was that they were the only one that didn't have a successful line of mechanical gyroscopes, so they wouldn't be competing against themselves. The first problem they had to solve

4425-756: The extremely sensitive quantum gyroscope . Applications of gyroscopes include inertial navigation systems , such as in the Hubble Space Telescope , or inside the steel hull of a submerged submarine. Due to their precision, gyroscopes are also used in gyrotheodolites to maintain direction in tunnel mining. Gyroscopes can be used to construct gyrocompasses , which complement or replace magnetic compasses (in ships, aircraft and spacecraft, vehicles in general), to assist in stability (bicycles, motorcycles, and ships) or be used as part of an inertial guidance system . MEMS gyroscopes are popular in some consumer electronics, such as smartphones. A gyroscope

4500-472: The first several decades of the 20th century, other inventors attempted (unsuccessfully) to use gyroscopes as the basis for early black box navigational systems by creating a stable platform from which accurate acceleration measurements could be performed (in order to bypass the need for star sightings to calculate position). Similar principles were later employed in the development of inertial navigation systems for ballistic missiles . During World War II,

4575-414: The force of gravity and the aircraft's centripetal acceleration. When the ball is centered in the middle of the tube, the aircraft is said to be in coordinated flight. If the ball is on the inside (wing down side) of a turn, the aircraft is slipping. And finally, when the ball is on the outside (wing up side) of the turn, the aircraft is skidding. A simple alternative to the balance indicator used on gliders

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4650-416: The gyroscope became the prime component for aircraft and anti-aircraft gun sights. After the war, the race to miniaturize gyroscopes for guided missiles and weapons navigation systems resulted in the development and manufacturing of so-called midget gyroscopes that weighed less than 3 ounces (85 g) and had a diameter of approximately 1 inch (2.5 cm). Some of these miniaturized gyroscopes could reach

4725-410: The gyrostatic behaviour of the interior invisible flywheel when rotated rapidly. The first gyrostat was designed by Lord Kelvin to illustrate the more complicated state of motion of a spinning body when free to wander about on a horizontal plane, like a top spun on the pavement, or a bicycle on the road. Kelvin also made use of gyrostats to develop mechanical theories of the elasticity of matter and of

4800-407: The military importance of the invention—in an age in which naval prowess was the most significant measure of military power—and created their own gyroscope industries. The Sperry Gyroscope Company quickly expanded to provide aircraft and naval stabilizers as well, and other gyroscope developers followed suit. Circa 1911 the L. T. Hurst Mfg Co of Indianapolis started producing the "Hurst gyroscope"

4875-399: The pilot's reference during a turn. When the needle is lined up with a hash mark, the aircraft is performing a "standard rate turn" which is defined as three degrees per second, known in some countries as "rate one". This translates to two minutes per 360 degrees of turn (a complete circle). Indicators are marked as to their sensitivity, with "2 min turn" for those whose hash marks correspond to

4950-415: The pitch angle and the angle of attack. Gyro X prototype vehicle created by Alex Tremulis and Thomas Summers in 1967. The car utilized gyroscopic precession to drive on two wheels. An assembly consisting of a flywheel mounted in a gimbal housing under the hood of the vehicle acted as a large gyroscope. The flywheel was rotated by hydraulic pumps creating a gyroscopic effect on the vehicle. A precessional ram

5025-400: The pivotal axis of the gyroscope frame (outer gimbal). This inner gimbal has two degrees of rotational freedom. The axle of the spinning wheel (the rotor) defines the spin axis. The rotor is constrained to spin about an axis, which is always perpendicular to the axis of the inner gimbal. So the rotor possesses three degrees of rotational freedom and its axis possesses two. The rotor responds to

5100-476: The rate-of-turn indicator and gives a safety measure of redundancy of systems. The slip indicator (the "ball") is still required. The slip indicator may be mounted separately in the panel, or, some attitude indicators now have a slip indicator included in the display. Gyroscope A gyroscope (from Ancient Greek γῦρος gŷros , "round" and σκοπέω skopéō , "to look") is a device used for measuring or maintaining orientation and angular velocity . It

5175-418: The roll axis) with limited freedom against a calibrated spring. The torque force against the spring reaches an equilibrium and the angle that the gimbal and gyro become positioned is directly connected to the display needle, thereby indicating the rate of turn. In the turn coordinator , the gyro is canted 30 degrees from the horizontal so it responds to roll as well as yaw. The display contains hash marks for

5250-401: The rotor can be in a fixed position. The rotor simultaneously spins about one axis and is capable of oscillating about the two other axes, and it is free to turn in any direction about the fixed point (except for its inherent resistance caused by rotor spin). Some gyroscopes have mechanical equivalents substituted for one or more of the elements. For example, the spinning rotor may be suspended in

5325-499: The rotor from torque, a necessary condition for an ideal gyroscope. A ring laser gyroscope relies on the Sagnac effect to measure rotation by measuring the shifting interference pattern of a beam split into two separate beams which travel around the ring in opposite directions. When the Boeing 757 -200 entered service in 1983, it was equipped with the first suitable ring laser gyroscope. This gyroscope took many years to develop, and

5400-471: The state of magnetic saturation in the approximation of quasimagnetostatics. In modern times, the gyrostat concept is used in the design of attitude control systems for orbiting spacecraft and satellites. For instance, the Mir space station had three pairs of internally mounted flywheels known as gyrodynes or control moment gyroscopes . In physics, there are several systems whose dynamical equations resemble

5475-434: The velocity of the object can be calculated. Integrating again, position can be determined. The simplest accelerometer is a weight that is free to move horizontally, which is attached to a spring and a device to measure the tension in the spring. This can be improved by introducing a counteracting force to push the weight back and to measure the force needed to prevent the weight from moving. A more complicated design consists of

5550-549: Was responsible for rotating the gyroscope to change the direction of the precessional force to counteract any forces causing the vehicle imbalance. The one-of-a-kind prototype is now at the Lane Motor Museum in Nashville, Tennessee. In addition to being used in compasses, aircraft, computer pointing devices, etc., gyroscopes have been introduced into consumer electronics. Dashpot A dashpot , also known as

5625-444: Was that with laser gyros rotations below a certain minimum could not be detected at all, due to a problem called "lock-in", whereby the two beams act like coupled oscillators and pull each other's frequencies toward convergence and therefore zero output. The solution was to shake the gyro rapidly so that it never settled into lock-in. Paradoxically, too regular of a dithering motion produced an accumulation of short periods of lock-in when

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