Schematic diagrams tensoresistive accelerometers. Principle of operation. Accelerometer - the types of sensors, drawings.
The accelerometer is a transducer that measures the acceleration of the object, which he acquired at the displacement relative to its initial position. Accelerometers are used to measure acceleration in the horizontal displacements caused by the acceleration of gravity. Currently mass produced accelerometers based on micro electromechanical systems (MEMS).
The principles of operation of the main circuit accelerometers. In Fig. shows the basic circuit tensoresistive accelerometers. The most simple accelerometer а) consists of a base, cantilever sensor with strain and inertial mass on the end. Calculation of the accelerometer is reduced to determining the cross section and span cantilever beam to a force equal to mass times acceleration measured. This type of accelerometers used to measure accelerations in the range from 0 to 0 .. 20g ... 20000g in frequency ranges from 0 ... 15 to 1500 Hz. Natural frequency accelerometers cantilever stiffness determined console and inertial mass. The frequency range can be extended using elastic elements without concentrated mass. The force acting on an accelerometer, determined by the product of the measured acceleration on the mass per unit length console.
Accelerometer, shown in Fig. б), characterized in that the frame has a sensor with the inertial mass, strengthened between the two cantilever beams. Compared with accelerometers cantilever in this case may be, to achieve a higher conversion rate for the same natural frequency. The frame element is calculated taking into account the anchorage racks at both ends. Accelerometers of this type can measure acceleration directly through small movements of the inertial mass with displacement transducers (see Fig., в). We accelerometers with strain gauges baseless highest conversion rate, but limited amplitude range. They are used to measure small accelerations (a few g) at frequencies 0 ... 25 Hz (see Fig. 53, в). Low frequency accelerometers are usually liquid damping, for which the sensor is placed in a sealed enclosure, filled, for example, poliksiloksanovoy liquid.
High frequency accelerometers perform on the circuit shown in Fig., д), е). They are the inertial mass, which is connected to the base via siloizmeritel solid or tubular section. Accelerometer is oriented so that the measured acceleration operated along the sensing element. Calculation of the accelerometer comes to sizing siloizmeritelya loaded with a force equal to the product of the acceleration of the mass.