Embodiments of the disclosure provide systems and methods for detecting a resonant frequency of an optical beam-steering device. The method may include driving the optical beam-steering device with a driving signal oscillating at a plurality of frequencies. The method may also include detecting, by an acoustic detector, an acoustic signal caused by a movement of the optical beam-steering device. The method may further include analyzing a spectrum, by a controller, of the acoustic signal. The method may additionally include determining, by the controller, the resonant frequency of the optical beam-steering device based on the spectrum.

Embodiments of the disclosure provide systems and methods for detecting a resonant frequency of an optical beam-steering device. The method may include driving the optical beam-steering device with a driving signal oscillating at a plurality of frequencies. The method may also include detecting, by an acoustic detector, an acoustic signal caused by a movement of the optical beam-steering device. The method may further include analyzing a spectrum, by a controller, of the acoustic signal. The method may additionally include determining, by the controller, the resonant frequency of the optical beam-steering device based on the spectrum.

A fishing pole including a handle and a seat that is integrated with the handle and structured to engage a line reel supporting a fishing line disposed about a spool of the line reel. The fishing pole further includes a flexible rod connecting to the handle and extending axially along an elongate axis. The flexible rod is structured to cast a fishing line a distance from the spool of the line reel. The flexible rod further includes at least two node locations. A plurality of rod guides are aligned with each of the at least two node locations and are operative to mitigate mechanical interaction with, and frictional drag on, the fishing line as it passes through each of the rod guides.

A fishing pole including a handle and a seat that is integrated with the handle and structured to engage a line reel supporting a fishing line disposed about a spool of the line reel. The fishing pole further includes a flexible rod connecting to the handle and extending axially along an elongate axis. The flexible rod is structured to cast a fishing line a distance from the spool of the line reel. The flexible rod further includes at least two node locations. A plurality of rod guides are aligned with each of the at least two node locations and are operative to mitigate mechanical interaction with, and frictional drag on, the fishing line as it passes through each of the rod guides.

Method for operating a device for wireless transfer of energy in the direction of an electrical consumer by means of inductive coupling, wherein the device has: a rectifier for generating a DC voltage from a grid voltage, an inverter fed from the DC voltage, which is designed to generate a pulse-width-modulated actuation signal, a power coil actuated by means of the pulse-width-modulated actuation signal, by means of which a magnetic alternating field can be generated to transfer the energy, and a communication unit, which is designed to exchange data bidirectionally with the electrical consumer, wherein the method has the following steps: sequentially carrying out a power transfer (LTX), a data exchange (DAT), a measurement of setup parameters (MAP), and a measurement of a resonance frequency (MRF), wherein during the power transfer (LTX), an electrical actual power emitted by the inverter is regulated to a predetermined electrical setpoint value, wherein during the data exchange (DAT), data are exchanged between the device and the electrical consumer by means of the communication unit, wherein during the measurement of the setup parameters (MAP), objects possibly arranged over the power coil, in particular foreign obj ects, are detected, wherein during the measurement of the resonance frequency (MRF), a resonance frequency of a resonant circuit having the power coil is ascertained, and wherein the measurement of the resonance frequency (MRF) is executed immediately before or immediately after the measurement of the setup parameters (MAP) or is executed immediately before or immediately after the data exchange (DAT).

Method for operating a device for wireless transfer of energy in the direction of an electrical consumer by means of inductive coupling, wherein the device has: a rectifier for generating a DC voltage from a grid voltage, an inverter fed from the DC voltage, which is designed to generate a pulse-width-modulated actuation signal, a power coil actuated by means of the pulse-width-modulated actuation signal, by means of which a magnetic alternating field can be generated to transfer the energy, and a communication unit, which is designed to exchange data bidirectionally with the electrical consumer, wherein the method has the following steps: sequentially carrying out a power transfer (LTX), a data exchange (DAT), a measurement of setup parameters (MAP), and a measurement of a resonance frequency (MRF), wherein during the power transfer (LTX), an electrical actual power emitted by the inverter is regulated to a predetermined electrical setpoint value, wherein during the data exchange (DAT), data are exchanged between the device and the electrical consumer by means of the communication unit, wherein during the measurement of the setup parameters (MAP), objects possibly arranged over the power coil, in particular foreign obj ects, are detected, wherein during the measurement of the resonance frequency (MRF), a resonance frequency of a resonant circuit having the power coil is ascertained, and wherein the measurement of the resonance frequency (MRF) is executed immediately before or immediately after the measurement of the setup parameters (MAP) or is executed immediately before or immediately after the data exchange (DAT).

Aspects of the present disclosure describe distributed fiber optic sensing (DFOS)—distributed acoustic sensing (DAS) based systems, methods, and structures that advantageously enable and/or facilitate the determination of natural frequency(ies) of civil infrastructures.

A device, and corresponding method, for determining a material composition of the pipe includes a probe, a resonance frequency measurement circuit, and a material analyzer. The probe includes an oscillator circuit and can be inserted into an interior cavity of the type. The probe also can emit electromagnetic radiation into the interior cavity via the oscillator circuit. The frequency measurement circuit is in operative communication with the oscillator circuit and is configured to output resonant frequency measurement data indicative of a resonance frequency of the oscillator circuit when inserted into the interior cavity. The material analyzer can receive the resonance frequency measurement data, and an additional measurement, and can output an indication of material composition of the pipe based on the resonance frequency measurement data and the additional measurement.

A device, and corresponding method, for determining a material composition of the pipe includes a probe, a resonance frequency measurement circuit, and a material analyzer. The probe includes an oscillator circuit and can be inserted into an interior cavity of the type. The probe also can emit electromagnetic radiation into the interior cavity via the oscillator circuit. The frequency measurement circuit is in operative communication with the oscillator circuit and is configured to output resonant frequency measurement data indicative of a resonance frequency of the oscillator circuit when inserted into the interior cavity. The material analyzer can receive the resonance frequency measurement data, and an additional measurement, and can output an indication of material composition of the pipe based on the resonance frequency measurement data and the additional measurement.

The disclosure provides a method for identifying a modal frequency of a beam bridge by considering influence of environmental temperature. The method includes the following steps: installing a sensor on a newly-built beam bridge without damage, measuring a dynamic response of the beam bridge cinder ambient excitation, recording temperature data, processing by a modal parameter identification method to obtain a modal frequency value at the temperature, and starting from a modal frequency corresponding to the temperature, carrying out iterative calculation to obtain the modal frequency at any temperature. The modal frequency value at any temperature is obtained by arranging a small number of sensors and carrying out a small number of tests, so that the influence of the temperature on the modal frequency is quantified, furthermore, the part of environmental influence is eliminated in future damage evaluation of the beam bridge, which allows for a more accurate damage evaluation result.