Piezoelectric Displacement Sensor

Piezoelectricity is the charge created across certain materials when a mechanical stress is applied.

Piezoelectric displacement sensor.

In the datasheets the free displacements of the actuators are given at nominal voltage. A semibipolar operation increases the strain amplitude while causing a stronger nonlinearity and hysteresis which result from the increasing extrinsic domain portions of the displacement signal fig. As a result the mass compresses and stretches the piezoelectric crystal. A an electric field applied to the material changes its shape b a stress on the material yields a surface charge.

They are very robust and are used in a wide range of industrial applications. Their displacement occurs perpendicularly to the polarization direction and to the electric field. A piezoelectric accelerometer consists of a mass attached to a piezoelectric crystal which is mounted on a case. Typically piezo contractors are flat components.

As discussed in the introduction piezo materials can transform an electrical voltage into a displacement making the material an actuator or can transform a displacement into an electrical voltage making the material a load or displacement sensor. Piezoelectric accelerometers rely on the piezoelectric effect of quartz or ceramic crystals to generate an electrical output that is proportional to applied acceleration. When the accelerometer body is subjected to vibration the mass on the crystal remains undisturbed in space due to inertia. The displacement of contracting actuators is based on the transverse piezoelectric effect whereby up to approx.

Piezoelectric sensors are versatile tools for the measurement of various processes. Piezoelectric pressure sensors exploit this effect by measuring the voltage across a piezoelectric element generated by the applied pressure. Piezoelectric sensors especially are used with high frequency sound in ultrasonic transducers for medical imaging and also industrial nondestructive testing ndt. Piezo actuators are usually driven unipolarly.

Direct and converse piezoelectric effect. This charge is proportional to applied force or stress. A transducer can be anything that converts one form of energy to another. The piezoelectric effect produces an opposed accumulation of charged particles on the crystal.

20 µm is nominally achieved. A piezoelectric transducer also known as a piezoelectric sensor is a device that uses the piezoelectric effect to measure changes in acceleration pressure strain temperature or force by converting this energy into an electrical charge. They are used for quality assurance process control and for research and development in many industries.