This paper presents an adaptive-step-control (ASC) strategy for autonomous chemical plume tracking (CPT) in both 2D and 3D spaces. The aim of CPT is tracking a target chemical flow back to its source and declaring its location. While the majority of related works are based on wheeled robots in 2D, the rapid development of rotorcrafts makes 3D plume tracking possible. Hence, in this paper, we first discuss the generalized form of moth-inspired CPT work flow, then extend the orthodox moth-inspired CPT from 2D to 3D. More importantly, we also propose an ASC strategy to deal with the “passing-by” problem and to gain better control performance. Simulation results are given to demonstrate that ASC can solve the inflexibility caused by “hard” step length in diffusive airflow, because it can autonomously adjust the step lengths of the robot according to the status of the environment, enabling our robot to stride confidently in the low chemical concentration areas and focus on highly suspicious areas.
Edge-drop control is important for silicon strip cold rolling, as the silicon strip is mainly used as a laminated core. Moreover, cold rolling is the key process for the thin strip edge-drop control, and a Sendzimir mill is one of the most popular cold rolling mills for silicon strips. Thus, the mastery of edge-drop control behavior for silicon strip cold rolling with a Sendzimir mill is beneficial for the improvement of the strip profile quality. With the finite element method, two models are built to analyze the edge-drop control behavior, one is the roll system and strip integrated elastic-plastic deformation statics model, and the other is the strip plastic deformation dynamics model. The first model provides the roll gap contour for the second model, then the strip profile can be calculated in the second model, which considers the transverse flow of the metal. Firstly, the compositions of edge-drop for the silicon strip are analyzed systematically, which are the edge-drop for work roll bending, the edge-drop for work roll flattening, and the edge-drop for transverse flow of the metal. Secondly, the influence of different rolling process parameters on the three parts are analyzed, such as the entrance thickness, the rolling reduction, the rolling tension, and so on; further, the influence of the roll contours are also analyzed. Finally, the edge-drop control behavior of the different rolling process parameters and roll contours are obtained. The research results provide theoretical guidance for edge drop control in the Sendzimir mill.