It is quite common for bus or subway passengers to watch videos on their smartphones during their journey. The screen rotation function that matches the orientation of the screen according to how the smartphone is being held is necessary at times like this. Today, we will look into the technology that makes this function possible.
This function is made possible through interaction between various sensors that detect movement. Various types of sensors such as acceleration sensors, geomagnetic sensors and RGB sensors are already in various smartphones on the market now.
The technology we will discuss today is the object orientation technology known as the Gyro sensor. The Gyro sensor is used in conjunction with acceleration sensors and plays a core role in action recognition.
The word Gyro means ‘to rotate’ in Latin and the term Gyro sensor refers to a sensor that detects the rotation angle of an object. Let’s take a closer look at Gyro sensors and how they work.
To understand the fundamentals of a Gyro sensor, let’s use a top as an example. When a top spins, it always stays vertical to the ground. Similarly, when a Gyro sensor is rotating, an axis exists through which the slope or incline of the object within which a Gyro sensor is held can be measured.
Since a Gyro sensor is a sensor that uses the revolution speed and angular velocity values of an object, it can also be referred to as an ‘angular velocity sensor’. Angular velocity can determine the Coriolis Force of an rotating object by calculating the change in the electrical signal. Coriolis Force is an inertial force that acts on objects that are in motion relative to a rotating reference frame.
A Gyro sensor can detect the rotation angle and inclination of an object and is used together with an acceleration sensor to measure direct movements to the X, Y and Z axes and have the desired effect of action recognition.
Currently, there are many products implementing Gyro sensors. Let’s look at these popular products.
Drones are currently the most popular products using Gyro sensors. Drones currently on the market commonly boast having 6 axis Gyro sensors but, in fact, they actually have 3 acceleration sensors and 3 Gyro sensors.
Because acceleration sensors measure direct movement, wind or air resistance can make precise movement difficult. Gyro sensors use the accelerator sensor measurements to determine the tilt of the drone and make adjustments.
② Virtual Reality
This year, LG Electronics introduced the virtual reality product known as 360 VR that highlights the mobility of the LG G5. This product has a Gyro sensor that detects the movements of the user’s face to display the virtual reality images.
Until now, most virtual reality efforts have been concentrated on gaming, but there is now a trend that is expanding the field of virtual reality into manufacturing and sports game viewing. In order to accomplish this functionality, it is necessary to detect rotation at 360 degrees and determine the orientation of objects and a Gyro sensor is required.
Also, sensor technology is seen as the major factor in the success of virtual reality. Gyro sensors are expected to be implemented in a wide range of industries.
③ Personal Mobility
Personal mobility technology is receiving a lot of attention lately. The most popular personal mobility products are the Segway and Ninebot, which are modes of transportation for 1-2 people.
These products have Gyro sensors installed in them and detect the angle of the passenger’s body to maintain balance. The technology makes it possible to move forwards and backwards as well rotate in any direction. Since these products use electricity and are environmentally friendly, they will continue to receive attention in the future.
④ Healthcare Wearable Devices
As with the smartphone revolution, wearable devices are becoming popular through the rapid development of scientific technology. According to research by the Korea Institute for Industrial Economics and Trade (http://eng.kiet.re.kr/kiet_eng/main/) the wearable device market is expected to increase 10 fold from USD 500M in 2013 to USD 55B in 2017.
Even today it is common to see people using products such as FITBIT Charge HR and XIAOMI MI Band. These products detect the user’s movement while exercising or sleeping and provide analysis of the user’s health.
As human motion detection will continue to be important, Gyro sensors in wearable devices will be an invaluable technology.
Gyro sensors will be very helpful in various fields but Gyro sensors can be disabled when subjected to sounds at certain frequencies. Moreover, last year, a Korean research team developed a technology that can disable drones with Gyro sensors using specific frequencies.
But wouldn’t it be dangerous if a drone in flight fell from the sky in a public place? Of course this type of technology would be an important factor in preventing attacks from drones, but more discussion is required on this topic.
We have now taken a look at Gyro sensors and their role in detecting object orientation.
According to predictions by the Korea Ministry of Trade, Industry and Energy (http://english.motie.go.kr/) the global sensor market is expected to grow from USD 79.6 B in 2012 to USD 141.7B in 2020. As Gyro sensors continue to be used on a large scale in IT devices, they will continue to receive a lot of attention.
Gyro sensors have already been widely commercialized and reducing production costs is the key. Let’s expect for many other cutting-edge technology sensors such as the Gyro sensor to make our lives more convenient in the future.
Written by Yong-Hoon Kim, LG CNS Student Reporter