Tu-PHS-07 - Overcoming Thermal Inertia in Robust Anemometers via Observer-Based Virtual Thermal Isolation

Event

EUROSENSORS 2026
2026-09-06 - 2026-09-09
Zurich

Band

Poster

Chapter

Physical Sensors

Author(s)

S. Huber, M. Mächler, T. Lamprecht, L. Kamm, D. Bertsch, C. Würsch - OST Eastern Switzerland University of Applied Sciences,Buchs (Switzerland)

Pages

578 - 579

DOI

10.5162/eurosensors2026/Tu-PHS-07

ISBN

978-3-910600-12-6

Price

free

Abstract

Miniaturized thermal flow sensors based on fragile MEMS membranes are standard in HVAC, respiratory devices, and mass flow controllers. While monolithic bulk-silicon sensors offer superior mechanical resilience, high thermal inertia severely restricts their dynamic bandwidth. In this work, we present an algorithmic virtual thermal isolation implemented on an off-the-shelf Nordic microcontroller to overcome this physical lag. The all-digital control loop combines a discrete Linear Quadratic Integral (LQI) controller with a Kalman filter (KF) to lock the bulk microchip to a constant temperature difference of 15 K above ambient. Flow velocities between 0 m/s and 20 m/s are dynamically extracted from the PWM duty-cycle controlling the heating power. This observer-based compensation overcomes substrate inertia, enabling fast flow sensing in challenging environments such as abrasive, particle-laden liquids or harsh hydraulic media.