Solved Servo Applications

High Frequency Oscillatory Ventilator

Medical ventilators provide breathing assistance for patients with the inability to do so.  This diaphragm controlled, high-frequency oscillatory ventilator (HFOV) provides alternative mechanisms of oxygen exchange and is used in cases where critical care patients can’t breathe on their own.  Delivery of breathable air is smaller and more frequent and generally meant for elderly adults and neonatal patients.

Motion Needs

Precision operation of voice coil motorized servo driven piston pump system.

Customer Requirements

    Achieve stability for mechanical vibration

    • System capable of producing frequency variability of 3 - 15 Hz oscillation
    • Extremely precise pressure/volume delivery with no deviation


    • continued
    • unfaltering operation
    • Overall consistent performance regardless of operating conditions.
    • Extensive initial testing to prove lifetime functionality

    Specific design parameters

    • Common servo drive platform needed for various models
    • Fast accel/decel response to provide precise volumetric flow
    • High velocity/bandwidth with no ripple

    Solutions Technology

      Standard product platform

      • Circuit architecture contained pots and switches for model variance and adjustibility
      • High bandwidth
      • fast response
      • matched (single-phase) voice coil motor tuning
      • Velocity mode
      • fast accel/decel
      • low-to-no ripple

      Over two decades of production

      • Market available
      • off-the-shelf analog servo amplifier used and offered to any customer today
      • Original initial production units still operating with zero failures
      • Lifetime reliability test still in progress
      • Recognized by customer with highest quality audit award