Several Applications of Acceleration Sensors

　　Game Controls

　　The accelerometer can detect changes in the up, down, left, and right tilt angles, so it is very simple to control the forward, backward, left, and right directions of objects in the game by tilting the handheld device forward and backward.

　　Automatic image flip

　　The acceleration sensor is used to detect the rotation movement and direction of the handheld device to realize the rotation of the image to be displayed.

　　Electronic compass tilt correction

　　The magnetic sensor determines the direction by measuring the magnitude of the magnetic flux. When the magnetic sensor is tilted, the geomagnetic flux passing through the magnetic sensor will change, causing errors in the direction of pointing. Therefore, if the electronic compass is not equipped with tilt correction, the user needs to place it horizontally. The principle that the acceleration sensor can measure the inclination angle can be used to compensate for the tilt of the electronic compass.

　　Compensation of Blind Spots in GPS Navigation Systems

　　The GPS system determines the position of an object by receiving signals from three satellites distributed at 120 degrees. In some special occasions and landforms, such as tunnels, tall buildings, and jungles, the GPS signal will become weak or even completely lost, which is the so-called dead zone. By adding an acceleration sensor and the inertial navigation we used before, we can measure the dead zone of the system. An integration of the acceleration sensor becomes the speed change per unit time, thereby measuring the movement of objects in the dead zone.

　　Pedometer function

　　Accelerometers can detect AC signals and vibrations of objects. When people walk, they will produce regular vibrations. Accelerometers can detect the zero-crossing point of the vibrations, thereby calculating the number of steps taken by the person or the number of steps taken when running, and thus calculating the displacement of the person. And using a certain formula, the calorie consumption can be calculated.

　　Anti-shake function

　　The acceleration sensor is used to detect the vibration/shake amplitude of the handheld device. When the vibration/shake amplitude is too large, the camera shutter is locked so that the captured image is always clear.

　　Flash message function

　　By waving the handheld device, text can be displayed in the air, and users can write the text to be displayed. This flash message function uses the phenomenon of human visual persistence and uses an acceleration sensor to detect the waving cycle to achieve accurate positioning of the displayed text.

　　Hard Drive Protection

　　Acceleration sensors are used to detect the free-fall state, so as to implement necessary protection for the mini hard disk. As we all know, when the hard disk reads data, the distance between the head and the disk is very small, so a slight vibration from the outside will have a very bad effect on the hard disk and cause data loss. The acceleration sensor can detect the free-fall state. When the free-fall state is detected, the head is reset to reduce the damage to the hard disk.

　　With the application of MEMS technology in the sensor field, the size of accelerometers can be made smaller and the performance can be made higher, which greatly promotes its application in the consumer electronics field and its market share is increasing every year.