Basic piezo technologies for motion control applications

The most common piezo actuators and motor types are “simple” piezo actuator, flexure-guided, piezo actuator, ultrasonic friction motors, piezo stepping motors, and Ultrasonic transducers. Different piezo actuators and motor types are available. The most common ones are:

08/23/2010


Basic design of an ultrasonic miniature linear motor. Source: Zebra Communications for Physik Instrumente L.P.Piezoceramic motors and actuators have fewer mechanical component parts to wear out and service, and have ability to provide more accurate positioning, attractive attributes for medical device manufacturers. Different piezo actuators and motor types are available. The most common ones are:

A) “Simple” piezo actuator—expands proportionally to voltage. Motion is proportional to drive voltage.

Operating principle of a PiezoWalk-type piezo stepping linear motor. Source: Zebra Communications for Physik Instrumente L.P.Sub-groups include:

  • Stacked actuator is the most common type, with high force, fast response, and short travel;
  • Shear actuator has fast lateral motion, and XY systems are available. They can have high force and very high frequency, though travel typically limited to 20 µm;
  • Tube actuator is mostly for microdispensing applications and atomic force microscopy (AFM) scanners; and
  • Bender actuator has long travel (deflection) to several mm, but low force and low frequency.

Dynamic phases in a stator plate of a piezo ultrasonic motor. Source: Zebra Communications for Physik Instrumente L.P.B) Flexure-guided, piezo actuator has frictionless flexures, and motion amplifiers provide longer travel, and extremely straight motion. Motion is proportional to drive voltage.

  • Integrated multi-axis systems are available;
  • Motion range up to 2 mm and above; and
  • Frictionless, without wear and tear.

C) Ultrasonic friction motors

  • Based on high frequency oscillation of a piezo plate (stator);
  • Unlimited motion, high speed, fast response (10 to 10s of millisecs);
  • Oscillation is transferred to a slide or rotor via friction; and
  • Due to friction, resolution is limited to typically 50 nm.

Basic principle of a piezo stack actuator. Source: Zebra Communications for Physik Instrumente L.P.D) Piezo stepping motors

  • Basically unlimited motion range;
  • Based on accumulation of small controllable steps;
  • Picometer resolution dither mode (direct piezo actuation);
  • Compact and high force to 155 lb. (for off the shelf units); and
  • Fast response (less than 1 millisec). Very high stiffness.

E) Ultrasonic transducers

  • Plate or disk-driven with a high frequency at resonance; and
  • Used as sensors or transmitters, and in nebulizers.

Design of a compact ultrasonic piezo motor linear translation stage. Source: Zebra Communications for Physik Instrumente L.P.Also see:

A piezo stepping linear motion animation, a 17-second video, courtesy of Physik Instrumente;

Piezo motors, actuators streamline medical device performance;

11 ways piezoelectric motors improve equipment performance; and

Control Engineering Machine Control Channel.

Physik Instrumente L.P. (PI) manufacturers nanopositioning, linear actuators, and precision motion-control equipment for photonics, nanotechnology, semiconductor, and life science applications; www.pi-usa.us. Jim McMahon writes about instrumentation technology for Zebra Communications; jim.mcmahon@zebracom.net. Edited by Mark T. Hoske, Control Engineering, www.controleng.com.



No comments
The Engineers' Choice Awards highlight some of the best new control, instrumentation and automation products as chosen by...
The System Integrator Giants program lists the top 100 system integrators among companies listed in CFE Media's Global System Integrator Database.
The Engineering Leaders Under 40 program identifies and gives recognition to young engineers who...
This eGuide illustrates solutions, applications and benefits of machine vision systems.
Learn how to increase device reliability in harsh environments and decrease unplanned system downtime.
This eGuide contains a series of articles and videos that considers theoretical and practical; immediate needs and a look into the future.
Additive manufacturing advancements; Machine vision enhances robotics; Fieldbus evolution; Process safety; Advice from System Integrators of the Year; Road to IANA
Salary and career survey: Benchmarks and advice; Designing controls; Remote data collection, historians; Control valve advances; Hannover Messe; Control Engineering International
System integration: Best practices and technologies to help; Virtualization virtues; Cyber security advice; Motor system efficiency, savings; Product exclusives; Road to Hannover
This article collection contains several articles on the Industrial Internet of Things (IIoT) and how it is transforming manufacturing.
PLCs, robots, and the quest for a single controller; how OEE is key to automation solutions.

Find and connect with the most suitable service provider for your unique application. Start searching the Global System Integrator Database Now!

The digital oilfield: Utilizing Big Data can yield big savings; Virtualization a real solution; Tracking SIS performance
Getting to the bottom of subsea repairs: Older pipelines need more attention, and operators need a repair strategy; OTC preview; Offshore production difficult - and crucial
Digital oilfields: Integrated HMI/SCADA systems enable smarter data acquisition; Real-world impact of simulation; Electric actuator technology prospers in production fields

(copy 5)

click me