Solutions

Piezo solutions are applied in both domestic as well as industrial applications. Some of these solutions are high volume applications like quartz watch, gas lighter, airbag, ultrasonic cleaning and parking sensors. Others are high end applications used for precise positioning and active damping. HEINMADE’s know-how and extended experience in development and production of solutions is in the following application fields.

  • Precise positioning using nano-stages with piezo actuators.
  • Active damping upto 6 DOF using collocated piezo sensor – actuator configurations.
  • Ultrasonic transducers.
  • Sensor solutions.

HEINMADE develops and produces customized solutions for first tier and OEM companies. Therefore the system solutions cannot be presented in detail. Below each of the application fields are highlighted and a general specification is listed to gain insight in possibilities.

Precise positioning;  Nanostages with piezo actuators

Nanostages consist of monolithic metal structures equipped with piezo actuators have a limited stroke of 100 to 300 µm in general and are supplied in 1D, 2D and 3D application formats. Some applications need additional degrees of freedom leading to XYZrZ solutions. For 6 DOF solutions a hexapod configuration may be considered. Some typical applications are microscopy (sample positioning) and wafer positioning.

Features

  • Multiple axis, Integrated amplifiers
  • Integrated feedback sensor
  • Frictionless (no wear), High resolution, Repeatability
  • Low profile compact design,Vacuum compatible

Typical specification

  • Stroke 100 to 300 µm
  • First resonance > 200 Hz
  • Repeatability, resolution sub nm
  • Materials steel, Al, Invar, Titanium

Active damping;  Collocated piezo sensor – actuator

For applications where machines have to hold position accurately in the sub-nanometer range, external disturbances are unwanted and should either be minimized by isolation or actively damped. For piezo hard mount solutions vibrations are sensed by a piezo sensor and actively compensated by a collocated piezo actuator.

Active damping systems up to 6 degree of freedom are developed based on customer demands. Solutions with criteria on stroke, mass, bandwidth and cross talk level between actuator and sensor are provided.

Features

  • Collocated sensor – actuator configuration
  • Monolithic metal structures
  • Frictionless
  • Solid state solution, no wear

Range of specification

  • Stroke 1 – 50 µm
  • Mass 1 – 20.000 kg
  • Bandwidth 0,1 to 5.000 Hz
  • Cross talk actuator/sensor 1e4 to 1e7

Ultrasonic transducers

Ultrasonic transducers are piezo components or piezo systems operated a resonance frequency and converting electrical energy in a new format. This means the electrical energy can be converted in electrical energy with a different voltage, converted in a sound wave in metal, water or air or converted in evaporated liquid. Essential for most of the application is that operating at resonance frequency the losses are as small as possible preventing overheating and optimizing for energy consumption.  In many cases an additional sensor is used to listen to the sound wave. In some applications the piezo actuators itself is used as a sensor.

Features

  • Frequency traced operation
  • Frequency sweep before operation
  • Applications from 20 kHz up to 2 MHz
  • Solid state solution, no wear

Sensors

Sensor applications of piezo are widely used and the number of applications is still increasing. In most of the sensor application it is not the piezo design itself that needs to be optimized but more the mechanics around the piezo. The mechanics forms a dominant factor in the performance and needs to make sure the maximum amount of charge is generated. The charge itself is equivalent with the introduced force to the piezo (i.e. deformation of the piezo). When forces (i.e. charges) are extremely small the electronic amplifier needs special attention.

Some examples are ;

  • Crack detection / Non-destructive testing; By introducing a sound wave in for example a silicon wafer, the sensor response between an uncracked and cracked wafer is not identical. The difference determines the amount and size of cracks present. This approach is both known as crack detection as well as non-destructive testings.
  • Deformation measurement; When applying a piezo sensor to a structure deformation of the structure also deforms the piezo sensor. The amount of generated charge is equivalent with the deformation. For some applications only detection of the signal is sufficient (for example in an airbag) for other applications strain levels of several picostrains (i.e. pm/m) can be precisely measured.