A wind speed detection system and a wind speed detection method are provided. The wind speed detection system includes a pipe body, a pressure sensing module, a suction pump, and a controller. The pressure sensing module is connected to a first opening through a first pipe and connected to a second opening through a second pipe. The first pipe has a main pipe. Two ends of a first alternative pipe are connected to two ends of the main pipe. When the controller performs a self-checking operation, the main pipe is closed and the first alternative pipe is opened. The controller starts the suction pump to perform forward suction. The controller measures a first air pressure through the first pipe and measures a second air pressure through the second pipe by the pressure sensing module. The controller calculates a reference wind speed value according to the first and second air pressures.

A physical quantity sensor includes a first element section in which first capacitances varying in accordance with a physical quantity have first saturation capacitance values at which the first capacitances are saturated by a first physical quantity, a second element section in which a second capacitances varying in accordance with the physical quantity have second saturation capacitance values at which the second capacitances are saturated by a second physical quantity smaller in absolute value than the first physical quantity, a multiplexer for outputting the first signals from the first element section and the second signals from the second element section, and a determination circuit that determines whether or not the level of the second signal input via the multiplexer reaches a threshold value which is a level of the second signal when the second physical quantity acts.

The present disclosure relates to a signal conditioning system for improving low-frequency measurement performance of an acceleration sensor. The signal conditioning system includes: a charge integration circuit, a high-pass filter circuit, a lead-lag network, an anti-aliasing filter circuit, and a gain adjustment circuit. An input terminal of the charge integration circuit is connected to the acceleration sensor, an output terminal of the charge integration circuit is connected to an input terminal of the high-pass filter circuit, an output terminal of the high-pass filter circuit is connected to an input terminal of the lead-lag network, an output terminal of the lead-lag network is connected to an input terminal of the anti-aliasing filter circuit, and an output terminal of the anti-aliasing filter circuit is connected to an input terminal of the gain adjustment circuit.

The present disclosure relates to a signal conditioning system for improving low-frequency measurement performance of an acceleration sensor. The signal conditioning system includes: a charge integration circuit, a high-pass filter circuit, a lead-lag network, an anti-aliasing filter circuit, and a gain adjustment circuit. An input terminal of the charge integration circuit is connected to the acceleration sensor, an output terminal of the charge integration circuit is connected to an input terminal of the high-pass filter circuit, an output terminal of the high-pass filter circuit is connected to an input terminal of the lead-lag network, an output terminal of the lead-lag network is connected to an input terminal of the anti-aliasing filter circuit, and an output terminal of the anti-aliasing filter circuit is connected to an input terminal of the gain adjustment circuit.

An inertial sensor based surgical navigation system for knee replacement surgery is disclosed. Inertial sensors composed of six-degree-of-freedom inertial chips, whose measurements are processed through a series of integration, quaternion, and kalman filter algorithms, are used to track the position and orientation of bones and surgical instruments. The system registers anatomically significant geometry, calculates joint centers and the mechanical axis of the knee, develops a visualization of the lower extremity that moves in real time, assists in the intra-operative planning of surgical cuts, determines the optimal cutting planes for cut guides and the optimal prosthesis position and orientation, and finally navigates the cut guides and the prosthesis to their optimal positions and orientations using a graphical user interface.

An inertial sensor device includes a first interface, a second sensor, a second interface, a host interface, and a processing circuit. The first interface is an interface for a first sensor configured to detect a first physical quantity in a first detection axis, a second physical quantity in a second detection axis, and a third physical quantity in a third detection axis. The second sensor is configured to detect the physical quantity in the third detection axis as a high-accuracy third physical quantity with a higher accuracy than the first sensor. The processing circuit is configured to output the first physical quantity and the second physical quantity to a host via the host interface, and output the high-accuracy third physical quantity instead of the third physical quantity to the host via the host interface.

There is provided a resonant sensor comprising: a substrate; a proof mass suspended from the substrate by one or more flexures to allow the proof mass to move relative to the frame along a sensitive axis; a first and a second resonant element connected between the frame and the proof mass; wherein the proof mass is positioned between the first and the second resonant element along the sensitive axis, and wherein the first and the second resonant elements have a substantially identical structure to one another; and drive and sensing circuitry comprising: a first electrode assembly coupled to first drive circuitry configured to drive the first resonant element in a first mode; a second electrode assembly coupled to second drive circuitry configured to drive the second resonant element in a second mode, different to the first mode; and a sensing circuit configured to determine a measure of acceleration.

A self-calibration method for an accelerometer having a proof mass separated by a gap from a drive electrode and a sense electrode includes initializing the accelerometer to resonate, applying a first bias voltage to the sense electrode and a second bias voltage to the drive electrode to obtain a first scale factor, measuring a first acceleration over a first time interval, swapping the first bias voltage on the sense electrode with the second bias voltage previously on the drive electrode and the second bias voltage on the drive electrode with the first bias voltage previously on the sense electrode so that a bias voltage on the sense electrode is set to the second bias voltage and a bias voltage on the drive electrode is set to the second bias voltage to obtain a second scale factor, measuring a second acceleration over a second time interval, and calculating a true acceleration.

A self-calibration method for an accelerometer having a proof mass separated by a gap from a drive electrode and a sense electrode includes initializing the accelerometer to resonate, applying a first bias voltage to the sense electrode and a second bias voltage to the drive electrode to obtain a first scale factor, measuring a first acceleration over a first time interval, swapping the first bias voltage on the sense electrode with the second bias voltage previously on the drive electrode and the second bias voltage on the drive electrode with the first bias voltage previously on the sense electrode so that a bias voltage on the sense electrode is set to the second bias voltage and a bias voltage on the drive electrode is set to the second bias voltage to obtain a second scale factor, measuring a second acceleration over a second time interval, and calculating a true acceleration.

A control circuit is provided for a sensor that determines a sensed property. The control circuit includes an input interface configured to receive high-resolution data and low-resolution data for the sensed property. The control circuit further includes circuitry configured to determine information on a functional state of the sensor using the high-resolution data and the low-resolution data.