Computational Experiments on the Step and Frequency Responses of a Three-Axis Thermal Accelerometer

Area of Science:

• Sensor Technology
• Mechanical Engineering
• Applied Physics

Background:

• Thermal accelerometers exhibit nonlinear responses at high accelerations, leading to ambiguous measurements.
• Existing literature presents conflicting models for horizontal acceleration frequency response (first-order vs. second-order).
• The vertical acceleration response of thermal accelerometers remains largely uninvestigated.

Purpose of the Study:

• To investigate the step and frequency responses of a three-axis thermal accelerometer.
• To develop a method for uniquely determining acceleration despite nonlinearities and large ranges.
• To characterize the frequency response for both horizontal and vertical acceleration axes.

Main Methods:

• Computational experiments were conducted to simulate accelerometer behavior.
• Temperature monitoring at two distinct positions was employed.
• Cross-axis sensitivity analysis was utilized to resolve acceleration ambiguities.

Main Results:

• A unique acceleration determination is achievable even for very large vertical acceleration ranges (-10,000 to 10,000 g).
• The frequency response for horizontal acceleration was confirmed as a second-order system.
• The frequency response for vertical acceleration was identified as a third-order system.

Conclusions:

• Monitoring temperatures and utilizing cross-axis sensitivity effectively addresses nonlinearities in thermal accelerometers.
• The study provides a clear characterization of frequency responses for both horizontal and vertical axes.
• This research enables more accurate acceleration measurements in demanding applications.