Wireless sensing charging based on multi-drone cooperation

In recent years, wireless charging technology is widely used for sensor charging. Though carts equipped with wireless charging tools were able to reach sensor nodes and continuously recharge them, their applications are limited and could not be used in many territories such as rugged mountainous terrain and severely damaged disaster areas. With the significant cost reduction of UAVs due to the mature technology, using UAVs to replace charging carts for wireless sensor networks is a future trend. In this study, the problem of energy replenishment and path planning for large-scale wireless sensor networks by multiple UAVs is considered. First, sensor nodes are distributed evenly by using an improved k-means clustering algorithm, modelling the problem of the UAV traversal over a certain range of sensors as a travelling salesman problem. Then, a heuristic algorithm is proposed to solve the path planning of UAVs and the hovering time at each sensor. The simulations show the effect of different charging ratios r on the number of non-functional nodes and the loss of the UAV. The experimental results show that the proposed algorithm is able to plan a sensible path for the UAV, which leads to a smaller UAV energy loss and a smaller number of non-functional nodes.