Questions tagged [gyroscopes]
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. These devices are used for measuring or maintaining orientation and angular velocity.
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What forces are responsible for the circular motion of the center of mass of a gyroscope-like setup in precession?
Suppose we have a disk (of mass $M$) connected to a rod (of mass $m$) attached to a fixed pivot. (Note that initially I thought of the rod hanging off a rope, but I realized it would be better to ...
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Optic Fiber Gyroscope Within Its Frame
I understand why the fiber optic gyroscope works as well the calculations for the time discrepancy between the beams travel time, but only as observed from out side the ring, "watching" it ...
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Why does the gyroscopic precession of a spin-stabilized bullet cause drift in the same direction as the spin?
I am trying to understand the physics behind the gyroscopic phenomenon called spin drift. Spin drift occurs to bullets that are spin-stabilized over the course of their flight.
Spin drift starts with ...
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Is Energy conserved in a spinning top?
When we spin a top (give it kinetic energy $K_0$) and place it on a table, it starts precessing around the vertical axis.
Is the total energy of the spinning and precessing top equal to the initial ...
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Euler's equation of motion for rigid bodies rotating with one rotation axis not through the body's center of mass [closed]
this is my first question in this forum. Thanks for all the knowledge and support shared throughout the whole website!
I have a body with rotations around 3 axes. I am looking for the external torques ...
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Why do vibration MEMS gyroscopes need two oscillating modes?
Everywhere I look, I see that MEMS gyroscopes need to have two modes, that are orthogonal in direction. However, that puts a lot of significance to the detuning of these modes, and calls for highly ...
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Sagnac effect and active ring laser gyroscope
I have to help with some lab classes soon and for that I will be tutoring an experiment where the students will use an active ring laser gyroscope and measure the beat frequency that occurs when the ...
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Verification of Accelerometer offset Formula, Offset occurring due to placement of Accelerometer away from centre of rotation in a rigid body [closed]
I have evaluated the Accelerometer offset occurring due to placement of Accelerometer away from the centre of rotation of body. In the below evaluation I am trying to calculate Accelerometer's reading ...
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Calculation of Accelerometer offset for Placement of Inertial measurement unit away from centre of mass
I am working on a 6DOF IMU that contains a 3-axis accelerometer and a 3-axis gyroscope, I am building a project to
plot the position and orientation of a vehicle/dirt bike in a 3d plane, However the ...
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How does a spinning disk respond to an impulse? [closed]
The figure shows a disk spinning with an angular velocity $\omega_z$. The disk is suspended from a long string.
I would like to know the following:
How does the disk respond to an impulse $J$?
What ...
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Proof that torque on a gyroscope equals derivative of its spin angular momentum
Definitions:
$\vec{\tau}$ = torque
$\vec{L}$ = angular momentum
$\vec{R}$ = radius
$\vec{F}$ = force
$M$ = mass
$\vec{A}$ = acceleration
$\vec{V}$ = velocity
I am familiar with the proof that $\vec{\...
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Pencil doesn't act as a spinning top
If one spins a spinning top, it'll stay up for a while before falling down. However, if one spins a pencil, it falls down immediately, just like if you didn't spin it at all. My question is why there ...
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Newton-Euler formulation
How to find the translational and rotational equations of motion when the center of gravity does not coincide with the origin of the fixed-body rotating frame?
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Gyroscopic bicycle wheel - forces on the wheel only
This is a standard problem in university physics, which I studied at university in depth. With higher concepts like angular momentum, it is fairly straightforward to explain the motion.
However, one ...
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Physical properties of a 3 dimensional gyroscope at speed [closed]
I have designed a 3D model of a gyroscope that has 3 rotors that revolve around x, y and z intersecting axis. All rotors share the same centre of mass at the datum.
I am trying to understand how these ...
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If angle random walk (ARW) is the integration of white noise [°/s], why is its unit [°/sqrt(hr)] and not [°]?
How can ARW have the unit [°/sqrt(hr)], if it's the integration of white noise which has the unit [°/s]? Shouldn't ARW be given ...
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Geodetic Precession of a Gyroscope in Hartle's GR Book
In 14.3, Hartle deduces the geodetic precession angle per orbit of a gyroscope in Schwarzschild geometry. Immediately after eq.(14.18), the book reasons that the angle deduced is physically measured ...
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Is there a naturally occurring siderostat (fixed orientation, absolutely nonrotating object as if locked to the distant galaxies or the universe)?
Often, a telescope is attached to an equatorial mount with a motor that counteracts the earth's rotation so that the telescope has no net rotation. It may be designed to counteract the known rotation ...
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How can precession produce a torque in the direction of precession when it has no angular momentum?
I this video, an 8 lb gyro on a rod supported at one end is spun up to several thousand rpm, and an assist is use to get the axis nearly horizontal. A small stick is used to nearly instantly stop the ...
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Is it possible to change the speed at which a wheel is freely spinning by moving only its axle?
Suppose we have a wheel spinning on a perfectly lubricated axle. Is it possible to change its angular velocity about that axle, by moving only the axle?
Due to the wheel's symmetry about the axle's ...
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Lagrangian Mechanics - Is the Given Answer Incorrect? [closed]
A heavy symmetric top rotating about a fixed point has Lagrangian
$$L=\frac{I_1}{2}(\dot \theta ^2 + \dot \phi^2 \sin ^2 \theta)+\frac{I_3}{2}(\dot \psi + \dot \phi \cos \theta)^2-mgl\cos \theta$$
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Will the inner gimbal continue to rotate if no friction?
The picture shows a gyroscope with a rotating disk.
Adding a force to the outer gimbal from a certain direction causes the inner gimbal (plus the disk with bearings) to rotate as well. When the force ...
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Resisting Precession of a Gyroscope
its known that if a torque is applied to a spinning gyro, the gyro will pitch. There's a lot physics on the pitch speed, but what is the torque to induce this pitching?
ps. I am building a gyro ...
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Measuring the curvature of the Earth using a mobile phone accelerometer + gyroscope
Suppose that you were on the surface of a sphere which is perfectly level everywhere. You are in a car or a plane, and you have a mobile phone with a gyroscope and an accelerometer that give a steady ...
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Does anybody know a physical explanation for the refractive index independence of the Sagnac Interferometer fringe shift?
It is generally accepted that the fringe shift produced in a fiber optic Sagnac interferometer is independent of the refractive index of the fiber. In fact, the waveguide aspect of the fiber is not ...
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Would a gyroscope have solved the longitude problem?
So I was thinking about the longitude problem, which was the problem of determining the longitude at sea. It caused great problems in sea navigation. See: https://en.wikipedia.org/wiki/Longitude#...
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Definition of rotation moment in a vertical surface during forced precession of a gyroscope
I have the following assumption:
Moment of gyroscope flywheel created by gravity force:
Rotation moment of natural precession due to gravity forces:
Since the flywheel does not drop:
However, when ...
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Antigravity force in powered precession gyroscope [closed]
I have an idea that a powered for rotation gyroscope with fixed precession can serve as antigravity engine. I also wonder of someone tried an experiment to prove that it does not work.
The following ...
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Does motorcycle counter-steering work by precessional motion?
When a motorcycle is going over a particular speed ($\approx 20$ m/h or 30 km/h) you learn in motorcycle class the best way to steer is using the so-called "counter steering";
I can't find ...
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Force on rod in gyroscopic precession
Suppose we have a gyroscope connected to a rod, undergoing precession parallel to the ground:
I'm trying to figure out how the torque on the rod agrees with the motion. Suppose the rod has a mass $m$ ...
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Gyroscopes and Conservation of Angular Momentum follow-up
I'd like to follow up on a question I asked two years ago under the same title (Sept. 22, 2019).
I am trying to understand just exactly how angular momentum around the vertical axis is conserved ...
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Electrical gyroscope
We all love the Gyroscope; basically it has a large angular momentum which stops it from being pushed over.
I'm going to assume ideal conditions for a moment- no resistance etc.
We can create angular ...
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What is the physical meaning of a pure imaginary force?
I am reading an article (this) and the equations result in an inertial force $F_g$ (which I understand as a fictitious force (?)) that is purely imaginary. The system consists of a gyroscope fixed to ...
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Is it the centripetal force due to precession that prevents a spinning wheel from falling? [duplicate]
An object tied to a rope will lift when swung around (like in a merry-go-round), due to the centripetal force.
If a rapidly spinning wheel is hanging from a rope at one side of the axis, it won't fall ...
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What causes the upward motion in a nutating top?
The locus of the rotational axis of a symmetrical rotating top with a fixed base is shown. This shows a nutation bounded by two circles.
What is the intuitive explanation as to why the top axis turns ...
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Will the spinning gyroscope make the plumb fall slower?
When winding a bike wheel up in an elastic double string in the ceiling, and then let the wheel spin vertically, it unwinds more slowly than if it was not spinning. I tried it.
But if a spinning disk ...
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Which is more accurate, a quantum gyroscope or ring laser gyroscope?
I can't find any source which says whether quantum or laser gyroscopes are more accurate. I'm also wondering what the advantages and disadvantages are of each technology.
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Why does this aircraft gyroscope has two degrees of freedom?
This is a Directional Gyro Indicator, it is a tied gyro, the spin axis is tied to the aircraft horizontal axis.
I read that this gyroscope has two degrees of freedom.
Please explain why is it so? What ...
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Are these equations correct for the motion of a gyroscope?
I was coding a gyroscope simulation and came up with some equations that I used for it.
So firstly,
torque = (change in angular momentum)/(change in time) = (vertical moment of inertia)(vertical ...
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Why does a rotating mass generate a torque on an attached object?
In this video, we see a little toy vehicle with two wheels that is unstable by itself. However, when an attached gyroscope is running (a rotating mass) it stabilizes itself.
When the mass starts to ...
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Gyroscope Angular Momentum Analysis
I'm puzzled by the following questions on gyroscope in HRK physics 5ed (p. 220)
Basically the gravity torque is $~τ=Mg\,L\,\sinθ~$. The angular momentum $L_s=I_s\,ω_s~$ has a horizontal radial ...
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Why does a precessing wheel remain horizontal, instead of flipping?
Suppose I have a wheel with an axle, such that one side of the axle is tied to a rope. I'm initially holding wheel in such a way, that the radius vectors of the wheel are perpendicular to a board. I ...
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What force am I feeling when I poke a gyroscope to spin off axis of rotation?
So this question is very simple however there is so much material on gyroscopes that I am getting my wires crossed.
What I understand, if you poke a gyroscope it will react 90 degrees in the direction ...
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Gyroscope force
I read that angular momentum is just pointed perpendicular to the plane of rotation (disk) as a convention.
Force is the change in momentum over time.
Is there actually a force in the direction of the ...
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Intuitive derivation for the precession rate of a spinning wheel
The derivation of the precession rate of a wheel hanging from a rope, as shown below usually involves taking
the total torque acting on the system and equating it to the change in angular momentum.
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Derivation of precession rate of a wheel gyroscope [closed]
I searched on the web and all I could find is the precession rate of a spinning top. But what I want is the derivation of the precession rate of a wheel hanging from a rope, as shown below:
which is ...
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Gyroscopic Effect at non-90 degree offsets
So I’m well aware of the way that the gyroscopic effect is normally described, that a torque applied to a rotating object will take effect 90 degrees later on the rotation (forgive me if I’m misusing ...
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Using gyroscopes to turn airplanes
Could multiple gyroscopes be used to change direction in a flying vehicle? Im a physics noob and don't really know what else to add...
If having one gyroscope allows you to change your direction in 90°...
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Why no torque along this axis?
Consider a gyrocompass consisting of a balanced spinning disk held in a light frame supported by a horizontal axle. The assembly is on a turntable rotating at steady angular velocity $\Omega$. There ...
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Purpose of outer housing in a 3 axis gimbal gyro
In this video Inertial Guidance System Professor Lewis shows how inertial inertial guidance system works. The setup consist of a 3 axis gimbal gyro.
Let $z$ be an axis pointing up , $x$ be an axis ...
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