The horizontal directional drilling technology is widely used to lay the underground pipelines. These pipelines are of small or medium diameters with a dip angle ranging from 10°to 20°, special pipelines to 30°. In-pipe robot is commonly used to detect the pipeline fault. A new type of telescopic in-pipe robot is designed in this article, which is driven by step motor and screw, and supported by wheels. The robot has advantages of waterproof grade of IP68, stable motion state, and larger traction force. The speed is between telescopic robots and wheeled robots. Through force analysis and calculation, its maximum climbing angle is larger than 35°. The robot has good passing ability through the pipelines with bends. The inertial technology is used to locate the robot under the condition of disturbances. The pipeline fault detection algorithm based on the visual identification technology is designed to detect the pipeline fault. It can not only achieve autonomic positioning but also detect the pipeline fault.

The subway-induced ground-borne vibration poses great challenge to the environment in the nearby districts. This problem is more prominent for near-station sections of subways since more buildings and human activities are influenced. And the train would be either accelerating or decelerating in this section; the vibration induced would be different from that induced by the train running on long straight subway sections. For the purpose of evaluating human comfort and designing vibration mitigation systems in the buildings, it is necessary to measure the ground-borne vibration induced by the subway. In the presented paper, a measurement system based on the CompactRIO system and LabVIEW platform is constructed. A network of acceleration sensors is placed to collect the vibration signals. This system is used to measure the ground vibration in terms of acceleration and the corresponding Fourier spectra at a near-station section of the Shanghai Metro Line 9. Some observations have been obtained towards the groundborne vibration induced by a train running underground near the station as well as the vibration decay with the distance from the subway tunnel.

Precision equipment is usually accompanied with vibrations during road or railway transportation. Sometimes the vibration exceeds the given limit, leading to the damage of the equipment. It is necessary to control the vibration during the transportation. However, it is still difficult to adjust the parameters of a designed vibration isolation system for the transportation of different precision equipment under various road conditions. Aiming at satisfying the vibration isolation requirements of different precision equipment, this paper proposes a parallel air spring vibration isolation system based on the principle of limiting lateral deflection. According to the measured parameters, a rigid-body dynamics simulation model of parallel air spring vibration isolation system is established. Then its feasibility is verified, and the optimal parameters of the vibration isolation system are obtained by a simulation. Finally, the vibration isolation system is built and installed in the equipment to carry out the real vehicle transportation test. The test results show that the transportation vibration isolation system based on the parallel air spring structure has not only excellent vibration isolation efficiency but also acceptable lateral stability. The research results in this paper can provide a reference for the design of the vibration isolation system for the large precision equipment transportation.

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With the rapid development of trenchless technology, measurement-while-drilling systems draw extensive attention. At present, measurement-while-drilling systems are generally based on magnetic surveying technology or singleaccelerometer measurement. In that case, the accuracies of these measurement-while-drilling systems are limited. In this article, a new measurement-while-drilling system with redundant accelerometers based on inertial technology is presented to improve the measuring performance of attitude, especially the measuring accuracy of roll. To reflect the influence of electromagnetic interference, the credibility estimation could be got by comparing the same attitude angles from the accelerometer and magnetometer. The calculation algorithm and experimental data are given in this article. Compared with traditional measurement-while-drilling systems, this new measurement-while-drilling system obtains better anti-disturbance property, higher measuring accuracy, and more reliable calculated results.

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