Active Shims for Long-Term Stable Positioning

Nanometer Precision – High Load Capacity – Long-Term Stability

If a dimension between two components or subsystems inside precision machines or in complex test assemblies changes, readjustment may often be necessary. PIRest active shims, the piezo-based „washers“, offer a simple solution for it. Once they have been installed in the machine, the distance between two components or machine parts can be readjusted with their help and without any further assembly as often as required and with nanometer precision. These PIRest actuators have a high load capacity and they are long-term stable. This helps to reduce the installation time of high-precision machines and optical assemblies and it also reduces downtime, particularly in difficult to reach places (in vacuum chambers or inside machines). If active shims are already designed into the machine during initial construction, it already helps to save time and costs during the first adjustment.

Demonstration of Long-Term Stable Positioning with PIRest Actuators

Reversible adjustment
Different incremental motion
Allows expansion and contraction
Long-term position stability without permanent voltage

Key Features of the PIRest Actuators

Nanometer resolution, micrometer displacement
No offset voltage required, no permanent power source required
Long-term position stability
Load capacity up to 4000 N per actuator
Flexible shapes and dimensions
Can be combined with classical piezo actuators for static error correction in dynamic processes

The Working Principle in a Video

How to Drive PIRest Actuators

The active shims can easily be controlled with the E-135 PIRest drive electronics:

  • Control of up to 6 PIRest active shims
  • ID chip detection for automatic configuration of operating parameters
  • Independent adaptation of operating parameters to the ambient conditions

Application Spectrum for PIRest Actuators



PIRest Actuators

Active Shims with Long-Term Stability and Nanometer Resolution
Version / Date
Version / Date
BRO63CN 2019-05
Document language
pdf - 7 MB
pdf - 6 MB

Press information kit - PIRest

zip - 2 MB

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