Actuation And Sensing Platform For Sensor Calibration And Vibration Isolation

摘要

A micro-system with integrated multi-axis actuation and sensing capabilities for in-situ calibration of long-term scale-factor drifts in the output signal of attached or monolithically integrated inertial sensors. The micro-system comprises a piezoelectric actuator, integrated position sensors, and a controller. The controller provides the electrical excitation signals to the actuator and receives and processes signals from the inertial sensors and the position sensors. The electrical excitation signals are adjusted to reduce undesired off-axis motion resulting from environmental vibration during operation or from misalignment and digressions from the process tolerance during fabrication. Capacitive position sensors allow for determination of the trajectory of the piezoelectric actuator and for electrostatic pull-down and lock-down of an actuation plate. Piezoelectric signals and piezoresistive signals are used to improve position sensing precision. The actuator trajectory and the corresponding output of the inertial sensors are used by the controller to determine the device parameters of the inertial sensors.

主权项

1. A micro-system for in situ calibration having integrated multi-axis actuation and position sensing capabilities, comprising:
a plate; a primary frame defining an inner space in which the plate is disposed; a plurality of connecting members disposed within the inner space and arranged around the plate, wherein each connecting member, in response to an applied stimuli, allows for movement of the plate in any of three geometric axes that are perpendicular to each other, each connecting member has a first end and a second end with the first end being attached to the plate, each connecting member is elastic and includes a piezoelectric element having a first surface opposing a second surface, where a plurality of partitioned surface electrodes are disposed on at least the first surface of the piezoelectric element; at least one primary sensor coupled to or integrated into the plate; a plurality of sensing elements that detect a motion trajectory of the plate; and a controller electrically connected to each of the connecting members and to each of the sensing elements in the plurality of sensing elements, wherein the controller is configured to actuate the plate by providing the applied stimuli to one or more of the plurality of connecting members while concurrently sensing motion of the plate from input received from the plurality of sensing elements.