Gyroscope – Strange Force Behind
These days we are strongly depending on science and technology, and because of this intensive use, we would not be able to imagine the consequence of missing some of those technological gadgets. As one interested in science, would like to probe the mechanisms of those handy gadgets, only to find that, if not all, but most of these tools are based on things and ideas, that were long invented far ago, even as far as many centuries back. Only few properties had ever changed, something like size and the material that used to make these items that powers these handy gadgets, the idea and workings remained the same throughout time, if I am not wrong, will continue to remain the same until we decide that our understanding in physics is somewhat wrong, and that is very unlikely.
I am going to show you a device, invented very long time ago, but the way it reacts, or operates, strangely enough, found a way to penetrate itself into our modern technological world. From airplanes to your bicycles to handy smart phones, gyroscope is there. So what is this thing? What kind of invention that is possibly used in airplane and can also be used in a smart phone?
What is gyroscope?
Gyroscope is a device that measures the orientation, mostly used as a compass where magnetic compass would not work, for example in space shuttle, satellites, where we cannot rely on magnetic field. It is also used to keep the orientation of flying machines, more than two dozens of gyroscopes are used in aircraft for auto piloting mode, and to automatically maintain the altitude.
Though in 1817, German mathematician Johann Bohnenberger first talked about the idea of gyroscope, it was actually in 1852, Léon Foucault, French physicist, who experimented with Earth’s rotation, created a device, and called it by its modern name. “gyros” in Greek means circle or rotation, and “skopeein” means “to see” or “look”, thus getting the name Gyroscope.
Gyroscope is made out of a wheel and axle, and it is designed in a way, where axle can take any orientation, or follow any axis. While Gyroscope is nothing more than a metal toy until its wheel starts to spin. When the wheel starts to spin, gyroscope starts to produce results with significant properties, at one point; spinning gyroscope starts to deflect gravity!
How it works?
Gyroscope is working, based on the principles of angular momentum, to explain simply, when the force is applied to the axle, top section of the gyroscope will try to move to the left, as the bottom section of the gyroscope will try to move to the right, and if the gyroscope is not moving then the wheel will flop over. But when the gyroscope is rotating, for example, when point A received a force, and that force tries to move the top part of gyroscope to the left, but, the point rotates so fast, when the point A rotates 90 degrees (consider point B), now it continues to move to left, but remember, that now point B, related to point A is quarter way around the circle, and at point B, moving left means, relative to point A moving right! Thus cancel each other’s force and remains in a certain position, and most importantly even gravity cannot defy this motion, after all its Newton’s first low of motion:
“Body in motion continues to move at certain constant speed along a straight line unless acted upon by an unbalanced force”.
And this is the reason, gyroscope starting to lose its precession when the speed of rotating wheel slows, and finally when the rotation of wheel comes to halt, the gyroscope falls.
Types of gyroscopes
There are many different kinds of gyroscopes out there, for example, the gyroscope in your iPhones or Android based smart phones are called accelerometers (in consumer electronics, it is often called this way that gyroscope, for note accelerometers are more than gyroscopes), which provides the way to present the screen in landscape or portrait mode based on the way the device is being held.
Other than rotating mechanism, gyroscopes based on other operating mechanism also exists, MEMS gyroscope, which works on vibrating mechanism, accelerometers are of this kind.
Ring laser gyroscopes are based on the principle of Sagnac efferct, which in principle, measures the time it take light to travel between two points, because certain rate of rotation makes a small difference in the time it takes the light to travel.
Another one is fibre optic gyroscope, this one too based on Sagnac effect and employs fibre optic cables to route the light, one important part of this type of gyroscope is that the optical fibre can be as long as 5 kilo meters!
There is also another type, which is very sensitive device uses quantum mechanical principles. It is based on the gyroscopic properties of electrons, atomic nuclei or photons. Also theory suggest that it is accurate enough to measure the minute rotational difference of Earth, but in practical way, quantum gyroscopes are not as accurate as mechanical gyroscopes, but this quantum gyroscopes are undergoing continuous improvements, therefore sooner or later, we can hope to achieve maximum accuracy and sensitivity.
Uses of gyroscopes
Most of current world automated moving systems, such as auto pilot mode in aero plane, guided missiles, satellites and auto driving cars (experiments) use gyroscope to guide and check the directions.
Normally gyroscopes are not used as standalone device but as a tool in a much more sophisticated system, such as inertial navigation system (INS), which employs a computer, accelerometer, and gyroscope.
INS is used to continuously calculate the position, orientation, and velocity of a moving object without the need for external reference. It is used in ships, aircrafts, spacecraft, guided missiles and satellites.
Hubble Space Telescope uses six gyroscopes to achieve maximum stability. At any given time, three of its six gyroscopes must work to ensure optimal efficiency. HST’s gyroscopes are extremely stable and can detect vey very tiny movement, therefore allowing us to keep the telescope precisely pointed for a long period of time.
The successor of Hubble Space Telescope, James Webb Space Telescope also uses the instrument called Fine Guidance Sensor (FGS), in the heart of that sensor there are gyroscopes!
Anti-gravity and Gyroscopes
Spinning gyroscopes can deflect gravity by not falling down, as it’s already explained in the above part of this article, the spin allows to cancel the force continuously as long as the wheel spin. This fascinating behavior has triggered amateur physicist and inventors to hope that it can also generate anti-gravity force.
There are many speculation in this talk, many leading physicist had already throw this concept, but some still believe that, unexplainable motion of gyroscope in gravity, seems to create an engine of its own.
In 1997, one Japanese team of scientists claimed that they have done an experiment, and the results were somehow pointing that gyroscope indeed produce anti-gravity. What they did was, in a vacuum, they put two laser beams, one on top and another on the bottom, and they allowed the gyroscope to fall through this beams. In a series of 10 runs, the team found that the gyroscope took about 1/25,000 of a second longer to fall when it was spinning than when it was stationary – equivalent to an anti-gravity effect of just one part in 7,000. The gyroscope itself spun 18000 revolutions per minute.
But the results are still ignored by major physicist, because it does not confront to our current world physics knowledge. But accepted or not, still some people out there trying to do something with gyroscope to prove that indeed it’s special and its one of a kind in physics, science and technology.
Source: Various internet sources, Britannica and Wikipedia.