An accelerometer is a device that measures the vibration and acceleration of motion of a construction. The force generated by vibration or acceleration causes a large amount of piezoelectric material to be squeezed out from the mass, producing an electrical charge proportional to the force applied to it.
Since the load is proportional to the force and the mass is constant, the load is proportional to the acceleration. This sensor type is used in various ways, from space stations to handheld devices, and you most likely already have an accelerometer; your smartphone.
They help your phone detect acceleration in any direction, and that is why your phone screen lights up when you turn it over. In the industry environment, accelerometers help engineers understand machine stability and monitor any unwanted forces or vibrations.
The accelerometer works utilizing an electromechanical sensor designed to measure static or dynamic acceleration. Static acceleration is a constant force acting on a body, such as gravity or friction. These forces are primarily predictable and consistent—for example, gravity.
Dynamic acceleration forces are uneven, and the best example of this is vibration or impact. A car accident is a perfect example of dynamic acceleration. Here, the change in acceleration occurs abruptly compared to its previous state. Accelerometers can detect acceleration and convert it into appreciable quantities, such as electrical signals.
There are two types of vibration sensors. The first type is a high impedance load output accelerometer. In this, the piezoelectric crystal produces an electrical charge that is directly connected to the measuring instruments.
Charge output requires special housing and equipment found in research facilities. A high impedance load output accelerometer is used in high-temperature situations.
The second type of accelerometer is the low impedance output accelerometer. A low impedance accelerometer has a load accelerometer as its front end. Still, it has a small built-in microcircuit and a FET transistor converting this load to a low impedance voltage that can interface with standard instruments.
Accelerometers have many applications in the industry. As already discussed, you can find them on the most complex of your portable devices. Let us take a look at some real-world accelerometer applications.
The screen rotation on your digital camera and smartphone is because of the accelerometer. The invention of airbags has saved millions of lives over the years. Accelerometers are used to move the airbags because the sensor sends a signal in the event of a sudden impact. Accelerometers also help drones stabilize their orientation during flight.
The accelerometers are also used in rotating machines to detect swerving vibrations to measure the stability of a platform or its tilt.
Moving machines produce vibrations, and these vibrations can be harmful to devices if amplified without supervision. Accelerometers are helpful in monitoring these vibrations and are increasingly used in industrial plants, turbines, etc.