There are four common wireless charging technologies, i.e., magnetic induction [4], magnetic resonance [5], laser light [6], and microwave conversion [7]. Each of them has pros and cons, and the timing of use. While using the magnetic induction technique, the difference between sensor and charger cannot exceed 5mm. A general case of charging mobile phones by a wireless charging technique is magnetic resonance. The maximum distance of magnetic resonance is about 3 meters long but it is hard to achieve. The laser light technique provides the longer charging distance by using an enormous transmission power, which is more dangerous. The charging distance of microwave conversion technique is higher than 10 meters and less influence with environment.When the distance between sensor nodes is far but charger’s charging range is finite, more and more chargers are needed to fill the coverage holes. To solve this problem, the authors in [8] investigated dynamic charger planning in an indoor WRSN environment, which is similar to this work. Chien et al. also try to combine a self-propelled vehicle and a charger into a charging vehicle, thereby the charger vehicle is able to serve more sensor nodes along with the charging path planned. The mobile charging problem can be mapped to a traveling salesman problem (TSP) which is a well-known NP-complete problem. They utilized the concept of Simulated Annealing (SA) algorithm to plan a charging path. Compared with other meta-heuristic algorithms, the charging method they proposed not only avoids falling into local optimum solution but also finds the optimal path faster. Simulation-based results showed that their proposed SA-based method can make WSN sustainable. In addition, it reduces the cost of charger planning