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 are "interaction particles" that cause gyroscope precession?
To move or rotate any object, we need some force, this force can interact with object in different ways, contact force(electromagnetic force between atoms), magnetic force etc. All these forces have ...
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Why does this gyroscope derivation fail for non-punctual mass distributions?
I've been working on deriving the equations of motion for a gyroscope in spherical coordinates. The setup involves a mass distribution (e.g., a spinning disk) whose center of mass is at a fixed ...
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Gyroscope Calculations
Above is an illustration of a gyroscope and now according to the right hand rule, I have given the directions of torque. Since it is a spinning wheel I have replaced the Force with the centrepetal ...
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Why doesn't net angular momentum vector coincide new axis of rotation in the case of gyroscopes?
Let's say we are given a gyroscope. Torque exerted by gravity will cause gyroscope to "flip" and hit the ground. Torque here coincides with the change of angular momentum vector. However, if ...
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Suited change of basis coordinates for solving relativistic Lense-Thirring and frame dragging
I have not been able to find in textbook (Landau, Wald) the rationales driving to the coordinate basis change proposed in MTW in order to comprehend the Lense Thirring / frame dragging effect in an ...
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How to understand gyroscopes by using vectors?
I’ve seen plenty of videos explaining how gyroscopes work, but almost non of them why they are constrained to work in such way. From seeing only angular momentum vectors, how could one predict ...
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Is it possible to reproduce tennis racket theorem instability with a gymbal under earth gravitational field?
The tennis racket theorem (whose effect is also known as Dzhanibekov effect), states that the rotational motion around the intermediate principal axis is not stable (that is, any small disturbance ...
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Can a translational torque cause a change in rotational angular momentum? gyroscope example
Please confirm if my understanding is correct: The example of a gyroscope suspended from a pivot is a case in which translational torque causes a change in the direction of rotational angular momentum:...
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Spinning top stabilisation for a type of aircraft/drone
Spinning tops use gyroscopic precession to be able to stay upright whilst spinning.
Would it be possible to use this phenomena to create a flying craft that would be stabilised by gravity and the ...
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What happens if we prevent gyroscope to precess?
If we apply some torque to spinning wheel in a vacuumed space in body frame y axis, wheel try to precess due to gyroscopic effect but it will be prevented by obstacles as seen from picture,
what will ...
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Torque applying on both rotating and non-rotating object
In rod reference frame:
origin is center of the rod,
pitching axis is coinciding with the rod
external torque is applied in rolling axis
If a torque is applied to non-rotating object(the rod and the ...
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In gyroscopic effect of a quadcopter, why does precession cause torque, not vice versa?
I don't know if the header corresponds to my actual quest but i will explain.
In quadcopter dynamic equations of Newton-Euler formation that I have encountered in all academic publications, torque ...
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When looking at Gyroscopes, does precession only occur if a force is applied perpendicular to the axis of rotation? or can it be a parallel force?
I am trying to simplify gyroscopic precession for PPL Helicopter students and in the process confused myself. Many texts define it as processing a force 90 degrees when the force is applied 'parallel ...
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Do gyroscopes still work inside event horizon?
Imagine a gyroscope falls into the event horizon of a supermassive black hole, what would happen to the gyroscope? will it remains in the same position before it falls into the event horizon?
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When the gyro moves down, does it spin faster?
First, I have a gyro, $\omega$ is its angular velocity
Then, I simple it to
When it moves down, there is
Gravity does work differently for A and B. Therefore, the angular velocity should be ...
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Moment of Inertia of a gyroscope
I saw that the moment of inertia could be calculated for bodies as the addition of the sum of their parts, so I was wondering if it could be calculated for the gyroscope that is pictured below
I was ...
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Spinning gyroscope loses weight?
I ran two tests with a toy gyroscope spinning on a weighing scale that is accurate to $1$mg.
The scale was reset to zero before the tests. The gyroscope was flipped over between test $1$ and test $2$. ...
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Why does a bullet precess in the opposite direction from gyroscope diagrams? [duplicate]
I am reposting this because it was not resolved when I first posted.
Bullet spin causes a bullet to become a gyroscope. Specifically, bullets have their center of pressure in front of their center of ...
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Conservation of Angular momentum for an irregular body rotating about three axes
I am having trouble understanding how conservation of momentum can be used to calculate final angular velocity for a body rotating in multiple axis with an asymmetrical MoI.
Suppose a satellite is ...
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Do gyroscopes show peculiar behavior during eclipses? [closed]
I'm curious about pendulums and their behavior during a solar eclipse. I also wonder about gyroscopes and if their behavior during stellar events has been observed. I wonder about the both of them, ...
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Conservation of Angular Momentum, why does person rotate only one way?
As seen from the video that i linked, when the wheel is spinning then he doesnt rotate, but as soon as he flips the wheel he will start to rotate. Why he doesn't rotate both counter and anticlock wise?...
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Choice of axis in analysis of gyroscopic precession
In many demonstrations of analysis of gyroscopic precession, the analysis goes on by choosing two axes, one about which angular momentum is calculated, another about which torque of gravity is ...
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How do I compute the bounds of random walk for a given ellapsed time?
I am trying to model random walk of a gyro, given some manufacturer specifications of maximum random walk in units of degrees per root-hour.
My first step was to generate white noise with a standard ...
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Why does the period of precession of a gyroscope have to be way larger than it's spin period so that it's motion can be modelled?
Mathematically, torque induced gyroscopic precession may be modelled with the following equation:
$$
{\displaystyle T_{\mathrm {p} }={\frac {4\pi ^{2}I_{\mathrm {s} }}{\ mgrT_{\mathrm {s} }}}={\frac {...
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Why a spinning top bounces in a direction vertical to the surface that it hits?
When a spinning top slowly advances and hit a surface (a wall), intuitively one would expect that the top gets bounced mostly along the wall, due to the friction between the top and the wall. But the ...
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Why is the bias instability read from my Allan Deviation plot different than my simulation input? [closed]
I have simulated a gyroscope at rest with angular random walk and bias instability, following the mathworks IMU simulation model found here. In conjunction with that simulation model, I am plotting ...
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How to measure bias instability of gyroscope with Allen deviation that has strange end behavior?
I have some simulated data from a model of an IMU's gyroscopes. I am trying to use Allan deviation to verify that we have correctly modelled various sources of error in the sensor data. I was able to ...
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Spinning Wheel subjected to Gravitational Force
have a question about the dynamics of a suspended horizontally rotating wheel subjected to gravitational force like in following picture I took from here:
At the beginning the wheel has an angular ...
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How can I optimally rotate accelerometer readings so that the integrated velocity ends up correct? [closed]
I attached an accelerometer (with gyro/magnometer) to a curling rock and threw it down the sheet of ice. The accelerometer was not flat, and it did not travel significantly in the $z$ direction. I ...
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How much should the disk/wheel spin for gyroscopic-precession to take place? Is there a threshold?
Suppose we have a spinning gyroscope whose disk is of mass $m$, spinning at angular velocity $\omega$, and attached to a rod of length $r$.
The precession of the gyroscope around the $z$-axis will be ...
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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 do bullets precess in the opposite direction from gyroscope diagrams?
Bullet spin causes a bullet to become a gyroscope. Specifically, bullets have their center of pressure in front of their center of mass. Therefore, when pressed, gyroscopic forces cause a bullet to ...
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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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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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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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Why is precession angular velocity of a gyroscope independent of the angle of its axis?
I'm making gyroscopes in my shop and studying precession. Studied dynamics in 1964 so may have forgotten a thing or two.
Consider a gyroscope or top spinning with its axis at angle $\beta$ with ...
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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?
Updated question, also includes somewhat of an answer.
To clarify the point about precession having no angular momentum, if the torque that induces precession is suddenly removed, the gyro suddenly ...
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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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