Using a Piezoelectric Actuator for Precision Motion Control

When it comes to precision motion control, very few types of actuators can match the accuracy of piezoelectric actuators. Naturally, this has made these actuators the preferred actuation solution in a myriad of applications. This article clarifies the various desirable attributes demonstrated by piezoelectric positioning systems.

These actuators have been commercially available for 35 years and have been continually adapted and evolved during this period. Quartz, barium titanate, lead niobate, and lead zirconate titanate are some examples of piezoelectric materials. The two main properties of piezoelectric materials are:

• They produce an electrical voltage when pressure is applied to them.
• They deform mechanically in response to an applied electrical voltage/load.

The entire range of piezoelectric actuators is based on these basic principles. The use of these actuators spans various industrial, commercial and consumer applications. Here are some key properties of piezoelectric actuators that make them the preferred choice in precision motion control:

• Infinite resolution: Piezoelectric actuators do not include moving parts, since they directly convert electrical energy into mechanical energy and vice versa. The absence of moving parts allows unlimited resolution.
• Sensitive Actuation – These actuators are highly sensitive, reacting to electrical exposure in a few microseconds or less. These actuators can even provide acceleration rates of up to 10,000 ge and even more.
• Ability to generate great force: With the evolution of piezoelectric actuators, it is now possible to move loads of several tons. Even with these loads, the linear motor/actuator can control displacement ranges down to 100 micrometers with subnanometer resolutions.
• No Magnetic Interference: Certain applications have zero tolerance for magnetic fields. Piezoelectric actuators are best suited for such applications because the piezoelectric effect is mainly related to electric fields. Such a linear actuator/motor is not affected by magnetic fields. They also do not produce magnetic fields of their own.
• Energy Efficient – ​​Even when these actuators are required to withstand heavy loads for a long time, they do not show significant energy loss. Static operation becomes surprisingly economical and energetic. Simply put, these actuators are capable of storing energy like an electrical capacitor.

In addition to the features mentioned above, piezoelectric actuators are also capable of normal operation in vacuum environments where quality precision motion control is required. And they are compatible for use in clean room applications, as they do not require the use of lubricants. Also, if your application requires an actuator that can operate at cryogenic temperatures, you can ask your manufacturer to create a special actuator suitable for such environments.

Given these characteristics, piezoelectric actuators are becoming more and more preferred for precision motion control in data storage, semiconductors, life sciences and medical technology, precision mechanics, optics, photonics, etc.