Classification and working principle of accelerometers There are many types of accelerometers: linear accelerometers and pendulum accelerometers are classified according to the displacement method of the detection quality; according to the support method, there are gem support, flexible support, air floatation, liquid floatation, and magnetic levitation. And electrostatic suspension, etc.; According to the composition of the measurement system, there are open-loop and closed-loop types; according to the working principle, there are vibrating wire, vibrating beam and pendulum integrating gyroscope accelerometers, etc.; according to the number of input shafts, there are single-axis , Two-axis and three-axis accelerometer; According to the classification of sensing elements, there are piezoelectric, piezoresistive and potentiometer.
The accelerometer can only move along one axis when the test mass is restricted by the support, and this axis is often called the input shaft or the sensitive axis. When the instrument housing accelerates along the direction of the sensitive axis with the carrier, according to Newton’s law, the inspected mass with a certain inertia tries to keep its original state of motion unchanged. There will be a relative movement between it and the shell, which will deform the spring, so that the test mass will accelerate its movement under the action of the spring force. When the spring force is balanced with the inertial force generated when the detection mass accelerates, there is no longer relative movement between the detection mass and the housing, and the deformation of the spring reflects the magnitude of the measured acceleration. The potentiometer is used as a displacement sensing element to convert the acceleration signal into an electric signal for output.
Accelerometers are widely used in control, handle vibration and shaking, instrumentation, automobile brake start detection, earthquake detection, alarm systems, toys, structures, environmental monitoring, engineering vibration measurement, geological prospecting, vibration of railways, bridges, and dams Test and analysis; mouse, high-rise building structure dynamic characteristics and safety and security vibration reconnaissance.