Wireless sensor networks have emerged as a key area of research in recent years. With the dominance of ubiquitous and pervasive era of computing, these networks present a rich infrastructure for valuable information. In this paper we focus on efficient data collection in sensor networks by proposing an algorithm to compute a coverage (collection) area using smart mobile objects. The algorithm proposed computes a collection area dynamically covering nodes around the mobile objects current location. It uses a weighed graph technique to identify nodes from which data can be collected efficiently by the mobile object discarding the rest. The proposed algorithm computes the collection area using Voronoi Diagrams and Delaunay triangle. We validate the proposed algorithm by simulating the algorithm over a Bluetooth based sensor network. We also evaluate the algorithms efficiency to compute the coverage area by changing the mobile objects context parameters.