Jun 22 2009
Piezoelectric actuators such as those supplied by Noliac are used for active vibration damping in mechanical structures where vibrations are undesirable. These structures are counting: automobiles, planes, aerospace, wind turbines, carriages, motors, machine tools, oil and gas platforms, buildings and constructions in a zone of seismic activity, undesirable vibrations of laboratory tables (especially optical), setups, etc.
Diminish noise and fuel consumption
Vibration damping diminishes noise, energy waste and fuel consumption. Further, it leaves machines more stable and pleasant to work with. For example, the vibration motions of engines, electric motors, or any mechanical device in operation are typically unwanted. Such vibrations can be caused by imbalances in the rotating parts, uneven friction, the meshing of gear teeth, etc.
One example is helicopters, where piezoelectric actuators are used actively for vibration damping. Helicopters are suffering from their environmental impact regarding external noise, fuel consumption and emissions, their low passenger comfort regarding cabin noise and vibrations and their limited performance regarding flight envelope, speed and range. One of the main sources of noise and vibrations is the main rotor, especially in fast forward and descent flight.
Active and passive damping
The damping of undesired vibrations in mechanical structures by means of piezoelectric components can be carried out either actively or passively. In active vibration damping, piezoelectric actuators make counter movements in the control loop. In passive vibration damping, the electrical energy generated by the structural vibrations in the piezoelectric actuators is converted into heat, for example, by means of resistors.
Piezoelectric actuators, including stacked multilayer piezoelectric actuators (SCMA), can be used anywhere where precisely dosed periodic counter forces are needed in structures.