Abstract: A method for measuring a magnetic field with a micro-sensor system includes applying a direct current (ITh) to a curved micro-beam to control a stiffness of the curved micro-beam; placing the micro-sensor system into an external magnetic field (B); selecting with a controller, based on an expected value of the external magnetic field (B), a given resonant frequency of the micro-beam; measuring with a resonant frequency tracking device the given resonant frequency of the micro-beam; and calculating in the controller the external magnetic field (B), based on (1) the measured resonant frequency, (2) the applied current (ITh), and (3) calibration data stored in the controller. The calibration data is indicative of a dependency between a change of the selected resonant frequency and the external magnetic field.

Abstract: A sensing method includes operating a microelectromechanical system (MEMS) microbeam device; measuring structural vibrations of the MEMS microbeam device over time; selecting an operational frequency foperating that is applied to the MEMS microbeam device, where the operational frequency foperating is different from a jump frequency fJump of the MEMS microbeam device, and the MEMS microbeam device is characterized by a frequency response curve that has a linear part and a softening or hardening part, and the operational frequency foperating is selected to be in the linear part; conducting an analysis of the structural vibrations of the MEMS microbeam device based on a linear equation that relates an amplitude of the structural vibrations to a frequency from the linear part; and detecting a frequency difference between the operational frequency foperating and the jump frequency fJump of the MEMS microbeam device based on the linear equation.

Abstract: Sensors and active switches for applications in gas detection and other fields are described. The devices are based on the softening and hardening nonlinear response behaviors of microelectromechanical systems (MEMS) clamped-clamped microbeams. In that context, embodiments of gas-triggered MEMS microbeam sensors and switches are described. The microbeam devices can be coated with a Metal-Organic Framework to achieve high sensitivity. For gas sensing, an amplitude-based tracking algorithm can be used to quantify an amount of gas captured by the devices according to frequency shift. Noise analysis is also conducted according to the embodiments, which shows that the microbeam devices have high stability against thermal noise. The microbeam devices are also suitable for the generation of binary sensing information for alarming, for example.

Abstract: Embodiments of multi-frequency excitation are described. In various embodiments, a natural frequency of a device may be determined. In turn, a first voltage amplitude and first fixed frequency of a first source of excitation can be selected for the device based on the natural frequency. Additionally, a second voltage amplitude of a second source of excitation can be selected for the device, and the first and second sources of excitation can be applied to the device. After applying the first and second sources of excitation, a frequency of the second source of excitation can be swept. Using the methods of multi-frequency excitation described herein, new operating frequencies, operating frequency ranges, resonance frequencies, resonance frequency ranges, and/or resonance responses can be achieved for devices and systems.

Abstract: Embodiments of multi-frequency excitation are described. In various embodiments, a natural frequency of a device may be determined. In turn, a first voltage amplitude and first fixed frequency of a first source of excitation can be selected for the device based on the natural frequency. Additionally, a second voltage amplitude of a second source of excitation can be selected for the device, and the first and second sources of excitation can be applied to the device. After applying the first and second sources of excitation, a frequency of the second source of excitation can be swept. Using the methods of multi-frequency excitation described herein, new operating frequencies, operating frequency ranges, resonance frequencies, resonance frequency ranges, and/or resonance responses can be achieved for devices and systems.

Abstract: A sensor, having a resonant frequency responsive to presence of an analyze, comprising a DC electrostatic excitation component, to produce a static force pulling a moveable element toward a backplate; an AC electrostatic excitation component, to produce an oscillation in the moveable element with respect to the backplate; and a sensor to detect contact between the moveable and the backplate.

Abstract: A sensor, having a resonant frequency responsive to presence of an analyze, comprising a DC electrostatic excitation component, to produce a static force pulling a moveable element toward a backplate; an AC electrostatic excitation component, to produce an oscillation in the moveable element with respect to the backplate; and a sensor to detect contact between the moveable and the backplate.