135results about How to "Accurate fault detection" patented technology

The invention relates to the field of wireless sensor networks and fault diagnosis, and discloses a method for carrying out fault diagnosis on wireless sensor networks. The method comprises the following steps: S1, carrying out online real-time acquisition on data measured by sensor nodes in a wireless sensor network; S2, detecting the fault of a single sensor node by using the space and time characteristics of the data; S3, detecting the fault of the whole wireless sensor network by using the correlation between two adjacent nodes; S4, carrying out attribute reduction on parameters obtained in the steps S2 and S3; and S5, obtaining a fault diagnosis result of the wireless sensor network according to the attribute reduction result obtained in the step S4. In the invention, the fault of a single sensor node is detected by using the space and time characteristics of data measured by sensor nodes in a wireless sensor network, and the rapid and correct fault detection on all nodes in the network by using the correlation between the nodes is realized.

An air bypass valve failure detecting device outputs an opening command to an air bypass valve when a throttle valve suddenly closes, thereby prevent surging from occurring in a second intake passage between a turbocharger and a throttle valve. When the opening command is outputted to the air bypass valve, failure detection for the air bypass valve is permitted only if an intake air quantity of an engine immediately before a closing command is changed to the opening command is equal to or larger than a predetermined value. Thus, it is possible to prevent the failure detecting device from erroneously determining that the air bypass valve is normal although valve closing failure of the air bypass valve has occurred. This is because, when the intake air quantity is smaller than the predetermined value, surging does not occur in the second intake passage even if the valve closing failure of the airy bypass valve has occurred.

A failure detection apparatus for preventing erroneous detection due to a degradation of a sensor and thereby accurately performing failure detection of a variable valve timing and lift control system is provided. The detection apparatus detects a failure of a variable valve timing and lift control system in an engine. The detection apparatus detects a vibration inside an engine cylinder, extracts the component of seating sound of the valve from the output signal of the sensor, determines an actual seating time of said valve from the component of seating sound, and calculates a target seating time of said valve based on at least one of a requested lift amount, a requested advance angle, and a requested open angle depending on the operating conditions. The detecting apparatus corrects the actual seating time for a stationary deviation between the actual seating time and the target seating time caused by degradation or unevenness of the sensor. The detecting apparatus determines a failure of the variable valve timing and lift control system by comparing the corrected actual seating time with the target seating time.

The embodiment of the invention discloses a fault detection method and device for a network path and network equipment. The method comprises the following steps: determining a target network path between an initiating device of path detection and a destination device of the path detection by a control plane; generating a detection message and path information, wherein the detection message is used for indicating the destination device to return a response message, and the path information comprises an identifier used for representing the target network path and a level; and transmitting the detection message and the path information to a forwarding plane, so that the forwarding plane transmits the detection message to the destination device through the target network path. By adopting the embodiment of the invention, the detection of the network path can be performed quickly and customer services are not affected basically.

An insulating state detection unit is configured to perform failure detection for switches, which connect a flying capacitor to a sample hold circuit for acquiring a charge voltage and a ground potential, by using a failure determination threshold value according to a variable value. That is to say, the insulating state detection unit is configured to decide the failure determination threshold value by taking, as a reference, a charge voltage of a capacitor of the sample hold circuit charged with electric charge amount corresponding to a charge voltage of the flying capacitor when the flying capacitor is charged with electric charge amount corresponding to an output voltage of a DC power supply.

The invention provides a tour inspection device with a 3D scanning function and a detection method of the tour inspection device. The tour inspection device comprises a laser transmitter, glass filters and CCD cameras and is characterized in that the CCD cameras arranged in an included angle mode are respectively provided with one glass filter, the laser transmitter and the CCD cameras are respectively connected with a PC storage processor, the device is carried on an unmanned aerial vehicle and detects overhead lines and pole towers from different angles. Compared with the prior art, the tour inspection device with the 3D scanning function can obtain three-dimensional images and size data of a detected device from different angles, is beneficial to judging the running state of an electrical device, can detect faults clearly, accurately and rapidly in all directions, and ensures normal running of electric transmission lines.

An amplifier failure detection apparatus for a radio transmitter that has a function for compensating for amplifier distortion of the radio transmitter and a function for determining amplifier failure has occurred by detecting that the gain of an amplifier has dropped a set level or more, in which: a gain-detection unit detects the gain of the amplifier; an alarm-detection-level-generation unit, which has a table for storing alarm-detection levels that correspond to input-amplitude levels, generates an alarm-detection level that corresponds to an input-amplitude level; and a comparison unit compares the gain detected by the gain-detection unit with the alarm-detection level, and generates an alarm based on the comparison results.

In a motor control unit, a current-carrying failure detection unit determines a first determination condition and a second determination condition. The current-carrying failure detection unit measures a duration of a state where the first determination condition is satisfied, and a duration of a state where the second determination condition is satisfied. When the first or second duration exceeds a predetermined reference period, the current-carrying failure detection unit determines that a current-carrying failure has occurred.

A battery-assisted bicycle includes a driving unit that accurately detects a failure in each of a torque detector, a crank rotation detector, and a motor rotation detector. The driving unit includes a crankshaft to which pedals are to be connected, a motor rotation detector that detects rotation of an electric motor, a torque detector that detects a torque generated at the crankshaft, a crank rotation detector that detects rotation of the crankshaft, and a sensor failure detector that detects a failure in at least one of the motor rotation detector, the torque detector, and the crank rotation detector based on detection results from the motor rotation detector, the torque detector, and the crank rotation detector.

An engine control system including an engine controller, a plurality of sensors coupled to the engine controller, and a neural network operating in the engine controller, and where upon failure of at least one of the plurality sensors, the neural network generates a representative value of the failed sensor.

The invention provides an indoor intelligent mobile robot and a control method. The global advancing path of the robot includes a plurality of key point positions of the path; when an obstacle existsin the advancing path, an obstacle avoidance point is arranged out of the original path, a local path of the robot advancing to the obstacle avoidance point from the current key point is planned, andafter the robot advances to the obstacle avoidance point along the local path, a local path of the robot advancing to a next key point from the obstacle avoidance point is planned again; and if a newobstacle appears during the process of the robot advancing along the local path, another obstacle avoidance point is set. A three-dimensional lidar is adopted for laser oblique shooting, the scanningpoint of the laser avoids a dynamic obstacle, and thus, laser data reflecting the surrounding environment information are acquired for building a surrounding environment map. Trackless autonomous navigation in an indoor complex environment with human mobility can be realized.

A power steering apparatus has a steering power assisting system coupled to tire wheels and a variable gear transfer system coupled to a steering wheel. The steering power assisting system includes a torsion bar rotation sensor and a first actuator rotation sensor to calculate a first pinion angle and a second pinion angle based on the detected rotation angles, respectively. The variable gear transfer system includes a steering sensor and a second actuator rotation sensor to calculate a third pinion angle based on the detected rotation angles. Sensor failure is detected by comparing the calculated first, second and third pinion angles.

A circuit device includes a differential input-to-single-ended output first amplifier, to an inversion input terminal of which, of first and second signals forming differential signals, the first signal is input and to a non-inversion input terminal of which the second signal is input, a differential input-to-single-ended output second amplifier, to a non-inversion input terminal of which the first signal is input and to an inversion input terminal of which the second signal is input, and a failure detection circuit that performs failure detection on the basis of an output signal of the first amplifier and an output signal of the second amplifier.

The invention discloses a few-mode optical fiber fault detection method based on high-order mode backward Rayleigh scattering, and belongs to the technical field of optical fiber fault detection. Theinvention aims to solve the problem of low sensitivity caused by fault detection of the few-mode fiber by only utilizing Rayleigh scattering of the fundamental mode back direction, and the fault eventpositioning of the few-mode fiber link cannot be accurately and effectively realized. An evaluation standard with rayleigh scattering at the back of a few-mode fiber high-order mode as fault detection is provided. By means of the characteristic of high detection sensitivity of the few-mode fiber high-order mode, effective characterization of different fault amplitude loss events can be achieved,comprehensive evaluation of few-mode fiber link fault events is achieved, and a powerful guarantee is provided for simple and accurate fault detection of few-mode fiber links.

Provided are an optical network fault detection device based on noise signals and a detection method thereof. The device is characterized in that a noise source and a signal processing unit are arranged in a main optical fiber between an optical line terminal and an optical distribution network unit. The noise source includes spontaneous radiation noise amplified by an online optical amplifier or introduced noise signals and is located on the side of the optical line terminal. The method includes utilizing spontaneous radiation noise amplified by the optical amplifier in an optical fiber main line or introduced noise signals, conducting detection by coupling a wavelength division multiplexer into branches of the optical network, filtering optical signals of corresponding branches to be detected through a reflection type adjustable filter, conducting relative processing on returned detection signals and reference signals in the signal processing unit and achieving fault location through relative peak value of relative curves. The device and the method utilize noise wideband characteristics to achieve proper online location detection of the wavelength division multiplexing passive optical network, and are simple in structure, convenient to operate and accurate in optical network fault detection.

The invention concerns a testing method detecting misconnected mechanical contacts between off-chip antenna and on-chip antenna circuit, wherein the testing method is a Built-In Self-Test method including a step of measuring at least one electrical parameter of on-chip antenna circuit connected to off-chip antenna which is representative of state of connection of said mechanical contacts.