In order to improve the travelling ability of the wheel-type pipeline robot in elbow section of pipeline, the model of drive ratios is proposed aiming at the pipeline robots with different configurations. Through the ...In order to improve the travelling ability of the wheel-type pipeline robot in elbow section of pipeline, the model of drive ratios is proposed aiming at the pipeline robots with different configurations. Through the movement analysis of the robot with different configurations in elbow section, the pose model of the robot is established, and the coordinates of the wheel centers and the contact points can be got through the calculation of the pose model. Based on the pose model established, the corresponding drive ratios are obtained combining with the relations of the velocities of wheel centers and rotative velocities of wheels under the movement condition with no interference. The virtual simulations and prototype experiments are carried out, and the drive ratios accuracy of the model when the robot moved in elbow without interference is validated.展开更多
A localization method based on distance function of projected features is presented to solve the accuracy reduction or failure problem due to occlusion and blurring caused by smog, when dealing with vision based local...A localization method based on distance function of projected features is presented to solve the accuracy reduction or failure problem due to occlusion and blurring caused by smog, when dealing with vision based localization for target oil and gas wellhead （OGWH）. Firstly, the target OGWH is modeled as a cylinder with marker, and a vector with redundant parameter is used to describe its pose. Secondly, the explicit mapping relationship between the pose vector with redundant parameter and projected features is derived. Then, a 2D-point-to-feature distance function is proposed, as well as its derivative. Finally, based on this distance function and its derivative, an algorithm is proposed to estimate the pose of target OGWH directly according to the 2D image information, and the validity of the method is verified by both synthetic data and real image experiments. The results show that this method is able to accomplish the localization in the case of occlusion and blurring, and its anti-noise ability is good especially with noise ratio of less than 70%.展开更多
基金Supported by the High-Tech Research and Development Program of China (2006AA04Z236)the"111"Project(B07018)the Self-Planned Task of State Key Laboratory of Robotics and System (HIT) (SKLRS200802C)
文摘In order to improve the travelling ability of the wheel-type pipeline robot in elbow section of pipeline, the model of drive ratios is proposed aiming at the pipeline robots with different configurations. Through the movement analysis of the robot with different configurations in elbow section, the pose model of the robot is established, and the coordinates of the wheel centers and the contact points can be got through the calculation of the pose model. Based on the pose model established, the corresponding drive ratios are obtained combining with the relations of the velocities of wheel centers and rotative velocities of wheels under the movement condition with no interference. The virtual simulations and prototype experiments are carried out, and the drive ratios accuracy of the model when the robot moved in elbow without interference is validated.
基金supported by National Natural Science Foundation of China(No.61403226)the State Key Laboratory of Tribology of China(No.SKLT09A03)
文摘A localization method based on distance function of projected features is presented to solve the accuracy reduction or failure problem due to occlusion and blurring caused by smog, when dealing with vision based localization for target oil and gas wellhead （OGWH）. Firstly, the target OGWH is modeled as a cylinder with marker, and a vector with redundant parameter is used to describe its pose. Secondly, the explicit mapping relationship between the pose vector with redundant parameter and projected features is derived. Then, a 2D-point-to-feature distance function is proposed, as well as its derivative. Finally, based on this distance function and its derivative, an algorithm is proposed to estimate the pose of target OGWH directly according to the 2D image information, and the validity of the method is verified by both synthetic data and real image experiments. The results show that this method is able to accomplish the localization in the case of occlusion and blurring, and its anti-noise ability is good especially with noise ratio of less than 70%.
