The Research Of Cooperative Obstacle Avoidance Approach Based On SA Algorithm In Mobile Wireless Sensor Network

As a research area which involves a wide subjects, and knowledge is relatively integrated, there has been a significant development of wireless sensor network(WSN) over the past few years. Compare with space fixed feature of traditional WSN, mobile WSN has a better flexibility and robustness in unknown environments. It is very suitable for the research of tracking target, and needs a flocking control model which easily adapt itself to the environment to guide node group towards the target. Meanwhile, how to avoid complex obstacles when sensor node group tracking target is also the focus and difficulty of research. Node group might be trapped in the concave obstacle, and lead to the failure of tracking target. Tracking target in mobile WSN is a research area which has a great potential, explosion is still in early stage, and there’s a lot of work to be developed.This article analyzed the feature of tracking target in mobile WSN, and investigated the flocking control model in group system, improved the flocking control model so that it can be adapted to mobile WSN. In addition, this article improved the SA algorithm which already has a high efficiency in obstacle avoidance. It changes the turning direction of the sensor node to tangent line of the intersection point between the velocity direction and the edge of the obstacle. Then it established cooperative obstacle avoidance model. This model has a higher efficiency in avoiding convex obstacles. However, node group might be trapped in the concave obstacle because the target applied gravity to nodes during the tracking process. It needs further improvement. This article introduced the cooperative obstacle avoidance model into concave obstacle environment. Temporarily cancel the attraction from the target when it comes to a concave environment judgment, and then constantly searching the path along the edge of obstacles, so that node group could reach the target in the end. Besides, this article introduces the cooperative obstacle avoidance model to engineering applications. Cooperative obstacle avoidance model is implemented in every single WSN node, group could towards the goal even without external force.Simulation results show that cooperative obstacle avoidance model fits well in avoiding convex obstacle compared with the flocking control model. It has higher time efficiency and average speed. Compared with original cooperative obstacle avoidance model, the improved model more adapted to the complex obstacle environment, has higher obstacle avoidance efficiency in concave obstacle environment. Engineering application demonstrates the practicality of the model. The research of this article provides a new method and key technology in tracking target of mobile WSN, results of this research will provide technological base to criminal investigation, security, medical and biology, and plays a very important role in the research of mobile wireless sensor network.