Sensor networks using mobile robots have recently been proposed to provide more flexible and efficient sensing. One of the key challenges under this paradigm is a management of transferring a huge amount of data. In this paper, we propose a model and protocol for session control exploiting controlled mobility in Multi-Robot Sensor Networks (MRSNs) to transfer the huge amount of data efficiently. Since a communication in MRSNs is mainly provided by a physical movement of the mobile node, the performance of the session heavily depends on this movement. However, if a node initiating the session can utilize sufficient amount of nodes, the performance of the session significantly depends on the wireless communication. In this paper, we propose a suitable method of session control which is determined the balance between movement and wireless communications based on local information such as the location, number, maximum-velocity and buffer-size of surrounding nodes. WISER/s also takes a system policy of either delay minimization or energy efficiency into consideration. In this paper, we describe a method of how to initiate, terminate and manage the session including dynamic selection of optimal nodes? formation. We evaluate the performance of WISER/s using mobile robots which are equipped with MICA2 mote and comparing with non-optimized method. The experimental results demonstrate that WISER/s achieves better performance than non-optimized method.