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A new method is proposed for mobile robot visual servoing using model-free visual targets under dynamic scenes. In the first stage, the ratio of depth information is calculated by using the geometric relationship between feature points and images. For the second stage, the relationship between various coordinate systems can be calculated via homography decompositions and coordinate transformation. Finally, an adaptive controller is adopted to drive the mobile robot to the desired pose. Both the simulation and experimental results show that when the scene changes, the mobile robot can complete the stabilization control. That is, when the linear velocity v→0 and the angular velocity w→0, the error e→0, then the robot stabilization to the desired pose 0.0 m, 0.0 m, 0.0°. [ABSTRACT FROM AUTHOR]

Mytilopsis sallei, an invasive alien species, has strong reproductive ability and high adaptability. It can severely endanger biodiversity of intertidal ecosystem after invasion. The intertidal zones and oyster breeding areas in some coastal areas of Guangdong Province have been severely invaded by M. sallei. To examine the potential habitat of M. sallei in China, we established a potential habitat prediction model of M. sallei using Maxent and ArcGIS method for China and global scales. The model was verified by the method of receiver operating characteristic curve (ROC) analysis and field investigation. The results showed that M. sallei could distribute with high probabili-ty in the area between North and South America, South India in Asia, Sri Lanka, the south coast of the Yangtze River in China, and in Van Dimen Bay of the southern hemisphere. In China, M. sallei mainly distributed in coastal provinces south of Shanghai. The main environmental factors affecting the suitable distribution areas for M. sallei were water vapor pressure, temperature, and solar radiation. After ROC detection, the AUC values of both the training and testing sets were 0.996, indicating that the prediction reached an excellent level. Our results provide theoretical basis for the risk assessment and management of M. sallei, and complement the potential habitat prediction of invasive species in China.