Other

Lei Liu

Chang Zhang

Shuangwen Liu

Xing Xie

Bin Hu

Paul Christopher Foster

Wei Na Cao

Joel Pazhayampallil

Xihong Jin

Xining Li

Jiajun Yao

Zhuang Li

Xiangjian Yang

Yanjun Zeng

Yongqiang He

Yunfeng Sheng

Gang Yan

A device for sensing a force includes a force-receiving surface with protruding regions and recessed regions, a deformation section, and a sensor for sensing strain caused by deformation of the deformation section.

Force sensing methods and apparatus using a deformation section

One variation of a method for registering distance scan data includes: accessing a first distance scan recorded, at a first time, by a first depth sensor defining a first field of view; accessing a second distance scan recorded, at approximately the first time, by a second depth sensor defining a second field of view overlapping a portion of the first field of view; calculating a first set of lines represented by points in a first portion of the first distance scan overlapping a second portion of the second distance scan; calculating a second set of lines represented by points in the second portion of the second distance scan; calculating skew distances between each pair of corresponding lines in the first and second sets of lines; and calculating an alignment transformation that aligns the first distance scan and the second distance scan to minimize skew distances between corresponding pairs of lines.

Method for registering distance scan data

The present invention discloses methods and systems for detecting the health status of a bolt which fastens a rotor blade of a wind turbine. Values of the axial stress/strain of the bolt and motion and orientation data are acquired in different aerial orientations. Values of the prestress/strain and load-stress/strain are obtained using the values of the axial stress/strain and the motion and orientation data. Values of the prestress/strain and load-stress/strain are compared with the reference values. The health status of the bolt, rotor blade, and the wind turbine system is determined based on the comparison results. The method is noninvasive and doesn't affect the function and performance of the bolt and the turbine system.

Method and system for detecting health status of a bolt that fastens a rotor blade of a wind turbine

The present invention discloses ultrasonic nondestructive methods for pipe wall thickness measurement at high or low temperatures. An ultrasonic detection device comprises a first and a second ultrasonic waveguide. The waveguide length is selected according to the surface temperature of a pipe under inspection. A first piezoelectric plate causes generation of a plurality of ultrasonic excitation signals which is transmitted to the pipe through the first ultrasonic waveguide. The plurality of ultrasonic excitation signals has different group speeds when traveling along the first ultrasonic waveguide. The reflected ultrasonic wave signals are collected and transmitted to a second piezoelectric plate by the second ultrasonic waveguide. The pipe wall thickness is calculated using an ultrasonic wave signal which has the highest group speed. The first and second waveguides are arranged parallel and side by side. An isolation plate is disposed such that the first and second waveguides go through the plate perpendicularly.

Methods and systems for pipe wall thickness detection

One variation of a method for temporally calibrating sensor streams in an autonomous vehicle includes: deriving a first set of longitudinal velocities of a reference point on the autonomous vehicle from a sequence of inertial data recorded over a period of time; deriving a second set of longitudinal velocities of the reference point based on features detected in a set of LIDAR frames recorded during the period of time; calculating a LIDAR sensor offset time that approximately minimizes a difference between the first set of longitudinal velocities and the second set of longitudinal velocities; and, in response to the LIDAR sensor offset time approximating an previous LIDAR sensor offset time, verifying operation of the LIDAR sensor during the first period of time.

Method for temporally calibrating sensor streams in an autonomous vehicle

The present invention discloses a method for extending the detection range of a structural health monitoring (SHM) system. A structure being monitored is scanned multiple times. A scan with no collection delay covers an original detection area of the SHM system. Scans with collection delays cover extended detection areas. The SHM system's detection range is extended when results of multiple scans with different collection delays are combined.

Method for extending detection range of a structural health monitoring system

A network node of a local area wireless network preferentially tries to connect with a first node having the primary connection relationship with the network node in a first connection time window; when the network node fails to connect with the first node under a predetermined condition, the network node tries to connect with a second node having the backup connection relationship with the network node in a second connection time window. After the network node is connected with and finishes communicating with the first or second node, the network node enters into standby or dormancy state and tries to establish connection in a subsequent first connection time window or a second connection time window. By using priority or backup routing method and setting connection time window, the power consumption management and networking management mechanism of each node of the network are simplified. Each network node can operate at a low power consumption level. Networking routes have certain degrees of freedom and can meet the network robustness requirements.

Networking method and system for wireless networks

The present invention discloses a train pantograph structural health monitoring system. The system includes one or more sensors mounted to or integrated with the train pantograph, a data acquisition unit for receiving signal or data from the sensors, and a processing unit for determining the train pantograph's structural health based on the received signal or data. Inspections via the system can be performed in real time continuously or periodically while a train is in service. It can also be performed offline while a train is not in service. Inspection method can be either passive, where sensors collect signals without generating excitation signals to the structure, or active, where some sensors are used as actuators to actively send excitation signals to the structure and other sensors or the actuators themselves collect the structural response signals. The data acquisition unit receives signals or data from sensors. The processing unit processes sensor data acquired by the data acquisition unit and determines if there are structural changes or damages.

Train pantograph structural health monitoring system

The present invention discloses an apparatus and method for scheduled, real-time, or on-demand monitoring of welding joints with in-situ sensors. The apparatus includes at least one ultrasonic actuator, at least one ultrasonic receiver, a control unit, and a signal processing unit. The control unit controls the ultrasonic actuators and the ultrasonic receivers. The signal processing unit determines the status of the welding joint based on the ultrasonic signals reflected from or transmitted through the welding joint. The invention enables monitoring of the status of the welding joint, tracking of the occurrence and expansion of the welding defect, and determining the position and severity of the defect in real time while the equipment is in service. The invention can optimize the maintenance efficiency, change the periodical inspection to automatic and real-time monitoring, and effectively prevent disaster accidents.

Apparatus and method for monitoring of welding joints with in-situ sensors

The present invention discloses a train coupler structural health monitoring system. The system includes one or more sensors mounted to or integrated with the train coupler, a data acquisition unit for receiving signal or data from the sensors, and a processing unit for determining the train coupler's structural health based on the received signal or data. Inspections via the system can be performed in real time continuously or periodically while a train is in service. It can also be performed offline while a train is not in service. Inspection method can be either passive, where sensors collect signals without generating excitation signals to the structure, or active, where some sensors are used as actuators to actively send excitation signals to the structure and other sensors or the actuators themselves collect the structural response signals. The data acquisition unit receives signals or data from sensors. The processing unit processes sensor data acquired by the data acquisition unit and determines if there are structural changes or damages.

Train coupler structural health monitoring system

The present invention discloses a photoionization detector (PID) system that can perform calibrations automatically. The PID system comprises a measurement gas chamber and one or more calibration gas chambers. The one or more calibration gas chambers each hold a type of calibration gas. In one embodiment, a volatile organic compounds (VOCs) measurement and a calibration measurement are conducted in the same gas chamber. In another embodiment, VOCs and calibration measurements are conducted in different gas chambers either simultaneously or at different times.

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San Ramon, CA, United States of America

Lei Liu