What is a Gyroscope and why should you care?

If you have ever thought about how a drone is able to stay stable without any input from the controls, or how even with shaky hands, anyone can take a remarkably stable video, even while running or walking, then this blog is for you. As the title suggests i will be talking about gyroscopes and hopefully, after reading this blog, you will be able to see how abundant and widespread their uses are in our daily lives.

so how does a gyroscope work? the most basic form of gyroscope that you may have seen in action before, probably consisted of a bicycle wheel and a piece of rope or string. the wheel is spun quickly while in a vertical orientation and then released to be left suspended from its centre by the rope. instead of just flopping over the wheel gracefully pivots around the rope while holding its vertical orientation, seemingly defying gravity.

To explain this, I will briefly introduce the concept of torque; we define this force (for objects rotating around a fixed axis) by the force applied, multiplied by the distance from the point it is rotating around. For a spinning wheel, this torque increases the angular momentum, in the direction of the torque, at a right angle to the rotation [1]. this momentum is what resists change in orientation and is what allows gyroscopes to stay fixed in space.

By measuring how thois wheel responds to external forces we can work backwards and calcualte the change in orientaion causing the wheel to behave in that way. This form of larger scale gyroscope is used for navigation in submarines for the pilots to accurately measure the pitch and yaw of the vessel while hundreds of meters below the ocean surface.

Now you’re probably wondering how the hell one would ever fit a big wheel like that in a drone, let alone a mobile phone. That’s where technology called (MEMS) come into play. Micro electromechanical systems (MEMS) are small chips that incorporate electronics as well as moving parts. They use tiny mechanical springs and an oscillating mass. when the chip is rotated, displacement of the oscillating body is at right angles to the rotation. Tiny capacitors read this displacement as a change in capacitance, converting this movement into an electrical signal.

So now you can see than if I am gaming on my mobile device and I tilt my phone to the left, the gyro is what is sending the signal telling the car that I’m driving that I want to turn left! And as mentioned at the beginning, as I’m taking a video, the gyro in my phone can feel every little tilt and smooth out the footage so that no trace of a shaky hand is left.

Gyroscopes are everywhere and hopefully now, whenever you see some cool stabilization tech, you will be able to say that you know what’s going on!

[1] Veritasium, gyroscopic procession – https://www.youtube.com/watch?v=ty9QSiVC2g0&pp=ygUQZ3lyb3Njb3BlcyB2ZXJhXA%3D%3D