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1answer
35 views

Can we spin a top in vacuum?

What happens to a top if we spin it in vacuum. Will it have any difference to rotating in a normal surface to a surface in vacuum.
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0answers
31 views

Differential precession due to gravitational waves

To motivate the question, Andy Strominger recently put out a paper on calculating the Sagnac shift of counterrotating beams due to the angular momentum flux of a passing gravitational wave. See ...
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0answers
29 views

Pendulum gyroscope

Is there a gyroscope (a device that enables orientation detection) built with only a pendulum and a gimbal? If I understand the terminology, this device would not use conservation of angular momentum ...
2
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0answers
44 views

How to find set point for PID controller for self balancing robot?

I am building a Self balancing robot and needs to tune PID controller to generate PWM signals. My robot chassis is home made and not in perfect alignment. I have placed 6 axis motion sensor on top of ...
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2answers
53 views

Magnet gyroscopic force spin

I was wondering whether a magnet exerts any measurable gyroscopic effects. I understand that magnetism is caused by alignment of spins of electrons which have angular momentum. (I realise that that ...
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0answers
84 views

Geodetic effect and Frame dragging

Two gyroscopes pointing perpendicular to each other were housed inside Gravity Probe B which performed polar orbit around Earth to test Einstein's theory of relativity. As the probe is orbiting ...
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0answers
85 views

What is the active and reactive gyroscopic couple?

What is the exact meaning of active and reactive gyroscopic couple?
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2answers
96 views

Clarify excerpt from Feynman Lectures on rotations in three dimensions

In The Feynman Lectures, vol. I, chapter 20 Feynman discusses rotations in three dimensions and explains angular velocities may be added as vectors; in particular he says: What about angular ...
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2answers
122 views

Can gyroscope work in zero gravity?

Most ships have two or more gyroscopes to balance on water, man made satellites uses gyroscope for orientation as they fall around earth. All these applications seems to be associated with gravity, ...
0
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1answer
64 views

Does precession of a rigid body change instantaneously?

I read some explanations of precession; this side for example summarizes briefly almost all what I have understood so far. But one thing bothers me: Following all this formulas, the precession ...
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0answers
17 views

When will be a suspended (not at the center of the mass) symmetric rotating gyroscope in stable or instable position?

The original question is what is in the title. I'm not sure about the answer so here is my solution, please correct me If I am wrong: It is known for a gyroscope what is in a homogenous gravity field ...
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3answers
2k views

How do we stabilise satellites so precisely?

Look at the Hubble Ultra Deep Field photo. The stars in it are on the order of 1 arcsecond across. To an order of magnitude, this is $10^{-6}$ radians in a $10\text m$ telescope which was held steady ...
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2answers
51 views

Do comets spin? Why do satellites/space station not spin?

Do comets spin? Why don't satellites or space-station spin? If spin is fundamental thing, then it should be found in all (moving) objects.
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2answers
1k views

How, exactly, does a reaction wheel work?

Reaction wheels, mounted on spacecrafts and satellites, are used for precision attitude control. It is not clear to me how they can do this, though. My best guess is that when a motor accelerates a ...
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1answer
1k views

How to calculate speed and distance from gyro, orientation and acceleration data?

In iOS 8 SDK, there's an API that gives you a distance covered by user over a period of time. I wonder how is Apple calculating distance, as it seems to work without GPS help. And since I have the ...
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0answers
215 views

Calculations to Determine Force Required for Gyroscopic Stabalization

I am currently undertaking a project involving gyroscopes, the aim of which is to stabilize a large object. I have read that gyroscopes work because of conservation of angular momentum, and if you ...
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0answers
15 views

Spinning top don't fall and stationary one can't stay upright [duplicate]

Why a spinning top do not fall but a stationary one falls. What kind of law is governing it.
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0answers
29 views

Most general gyroscope motion [duplicate]

In Kleppner & Kolenkow's Introduction to Mechanics (Amazon link), the general gyroscope motion including nutation was derived using the approximation condition $\Omega T \ll 1$ where $\Omega$ is ...
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1answer
47 views

Gyroscope motion: Why is $\vec{\Omega}$ vertical?

Since I can't sketch here I am referring to: Feynmanlectures-Gyroscope Assume that you have got a gyroscope (as in Figure 20-3 in the link) that pivoted and can turn around any axis. Let $\vec{L}$ be ...
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6answers
9k views

Can a car steer on a frictionless surface?

Do the front tires of a car act like gyroscopes, such that a car could steer on a frictionless surface?
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1answer
62 views

Counter-rotating flywheels for “flying saucers”

In 1974, while living in a farmhouse next to the Johns Hopkins Applied Physics Laboratory in Laurel, MD, I became obsessed [to the total consternation and perturbation of my wife, of that time, and my ...
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3answers
72 views

Why do we add the spin angular velocity and orbital anglar velocity when asked to calculate total angular velocity of Gyroscope?

Normally when we talk of angular velocity we mean how the angle of a vector changes with time with respect to an origin.Thus the oribital angular velocity of gyroscope makes sense to me.However I find ...
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0answers
47 views

Noise of a fiber optic gyro

I have not much experience with noise handling or calculations, furthermore in my researches couldn't find a similar problem, so here is my attempt: Having a fiber optic gyro that is rated with a ...
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0answers
107 views

Which force is necessary for providing centripetal force to a rotating gyroscope?

When a gyroscope is precessing around an axis due to a certain applied torque, if we look at the center of mass , it is going around in circular motion. So there must be some force which provides the ...
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3answers
120 views

Are gyroscopes the only way to maintain the orientation?

Gyroscope is quite popular, one can even find it in iphone etc. But, is such Gyroscope the only way? are there any other ways to build machine that to measure or maintain the orientation?
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1answer
692 views

How to use accelaration data of moving object to calculate distance?

I read couple of similar question on this forum and few blogs on web, though I am still confused,I am determined to calculate object displacement using accelerometer data. So, I tried using ...
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0answers
74 views

The Linear acceleration in Gyroscope

I am trying to understand theory behind the Gyroscope. I found this article that explains things in much detail. But I am unable to understand how that perpendicular acceleration components (a1, a2) ...
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2answers
124 views

The charm of the gyroscope [closed]

I am fascinated by the gyroscope, like everyboy who was so lucky as to get such a toy as a kid. But probably also grown-ups are not immune to its charm. I am not asking for a theoretical explanation. ...
4
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1answer
190 views

What does a MEMS gyro measure during off-axis rotations?

I've been working with MEMS gyroscopes in hobbyist projects for years—but it's recently come to my attention that I don't have any principled understanding of what rotation rate measurements ...
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0answers
197 views

Direction change of gyroscopic precession with change in moment of inertia

In the classic bicycle wheel gyroscopic precession, using the right hand coordinate system of xyz and right hand rule of rotation, Such as X axis is in the longitudinal direction (spin axis) z ...
8
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1answer
701 views

Defy gravity torques with gyroscopes?

Context On the following drawing, a platform is hung from the ceiling not exactly from its centre of gravity. Because of this it can't sustain an arbitrary orientation for long; I want to increase ...
0
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1answer
418 views

Model the gyroscopic effect for 3axes stabilisation

Context I am trying to stabilise a platform on a guimbal using 3 axes gyroscopes. I have made tons of research (same problem for weeks even months now) without being able to properly model the 3 ...
7
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1answer
111 views

Why does the heaviest point on a spinning ball tend to become the topmost pole? [duplicate]

I have a mostly hollow, small clear plastic ball. Inside the ball is a weight stuck to the edge but the weight is smaller than the ball so the ball will always come to rest with the weight at the ...
3
votes
2answers
494 views

Why does pitch in a helicopter take effect 90 degrees later?

In a helicopter if you want to give it a forward pitch, you change the angle of the blades when it is in this position ---- So the two blades experience unequal lift and because o gyroscopic ...
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2answers
506 views

Describing a motion of gyroscope with gimbal

Can you tell be how to set the equations to describe the motion of this machine in movie "Contact": https://www.youtube.com/watch?v=TSaO9VGjLXc This is gyroscope with gimbal, am I right?
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1answer
518 views

Torque and angular acceleration with bicycle wheel

This might be a simple problem for many of you. However, please help me understand it too. I have been looking trough a lot of materials online, and I still have the following questions, that would ...
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0answers
53 views

What is the longest distance over which echolocation is effective?

Some animals, most notably bats, use echolocation in order to navigate and detect the location and size of objects and prey. This usually takes place over short distances. What are the theoretical ...
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1answer
724 views

What makes a wrist-energized gyroscope rotate faster?

I'm considering a wrist-energized gyroscope, shown below (after my daughter let it fall and it broke open). That one was sold as Roller Ball, but variants are known as Powerball, DynaBee, Dynaball, ...
4
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1answer
226 views

Understanding gyroscopes

Considering the typical situation of a rotating bicycle wheel held by one end of its axle by a rope tied to the ceiling: gravity torque is the time derivative of the angular momentum, and in this case ...
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0answers
90 views

Bottom magnetic levitation

There are many decorative devices, that keep a small metal sphere levitating in air by attracting it to a top electromagnetic coil while monitoring their height by optical sensors. There is also the ...
0
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1answer
169 views

Purely mechanical description of how gravity causes a gyroscope to precess

I know the vector equation that relates torque to moment of inertia and angular momentum. What I want to know is what physical mechanisms actually occur to keep the gyroscope from falling. Where is ...
0
votes
1answer
123 views

Why does precession only occur at high angular speeds?

I'm trying to understand precession for a gyroscope or top. I do understand why precession occurs using the vectors for the weight force and torque and angular momentum. But what I don't understand ...
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1answer
63 views

Can we define angular momentum for the wheel under motion?

According to the definition of angular momentum: Angular momentum, moment of momentum, or rotational momentum is a vector quantity that represents the product of a body's rotational inertia and ...
1
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0answers
73 views

Movement of a gyroscope with non-fixed axis

Assume one has a gyroscope rotating around an axis with both ends leaning on a dedicated semiplane as shown on the picture below. There is no friction either between the rotor and the axis or between ...
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2answers
270 views

Will a wheel rolling down a hill ever fall over?

Say I have a detached bicycle wheel and I roll it down an infinite, flat, asphalt inclined plane, in air (ie there will be a terminal velocity). When, if ever, will the wheel fall over? I've been ...
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2answers
1k views

how to determine direction of gyroscopic couple on car?

How can I determine the direction of the force acting due to gyroscopic couple on a car's wheels when it is taking a turn to it's left side?
4
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2answers
592 views

Why do gyroscopes not maintain their stability as seen in this video

What exactly causes gyroscopes to oscillate as seen in this video. http://www.youtube.com/watch?v=gdAmEEAiJWo Even when my toy gyroscope spins on Earth, I get oscillations. Is this a result of ...
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1answer
359 views

Physics of the point of contact for a spinning top

I understand how spinning tops don't tip over, cf. e.g. this and this Phys.SE questions. What I'm more interested is in identifying the factors that determine the direction the spinning top moves to? ...
3
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2answers
4k views

What causes precession or nutation in a spinning object?

What causes precession in a spinning object? What causes nutation in a spinning object? What causes a top, gyroscope, and the earth to wobble? Just because it's a simple question, I'm not ...
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1answer
118 views

Gyroscope bombardment

Let's say I have a spinning steel ball that I have somehow managed to be completely free in all axes of movement. If I fire a BB at it with enough force on a north-south (to the ball) angle, what will ...