Wireless Sensor Network-Based Communication for Cooperative Simultaneous Localization and Mapping Gurkan Tuna 1, , V. Cagri Gungor 2 , Stelios M. Potirakis 3 1 Department of Computer Programming, Trakya University, Edirne, Turkey 2 Department of Computer Engineering, Abdullah Gul University, Kayseri, Turkey 3 Department of Electronics Engineering, Technological Education Institute of Piraeus, Aigaleo, Greece Abstract This paper presents a novel approach of using a Wireless Sensor Network (WSN) as the communication means for Multi-Robot, Cooperative, Simultaneous Localization and Mapping (CSLAM) applications investigating the associated design challenges and suggesting corresponding solutions. Although the proposed approach brings several benefits including an increased coverage and communication range, self-organization capabilities, quick deployment, and flexible architecture, the realization is interrelated with performance in terms of energy efficiency and reliability. In this respect, the applicability of the WSNs for the presented approach is investigated. Centralized and distributed map merging methods in WSN-based CSLAM are evaluated in detail and the impacts of packet delays and losses on the performance of CSLAM algorithms are shown. Additionally, the involved network congestion and contention dynamics are presented, while the effects of observation range, speed, time intervals between observations, and odometry readings on the SLAM accuracy are shown based on an extensive set of simulation studies. Keywords Cooperative simultaneous localization and mapping; map merging; wireless sensor networks; the network simulator (ns-2). 1 Introduction Simultaneous Localization and Mapping (SLAM) is a process used by mobile robots to build a map of an unknown zone by using a sequence of measurements, while at the same time they keep track of their current locations [1]. Due to the measurement noise and motion noise, uncertainty is inherent in robotic mapping [1], [2], [3]. A team of multiple robots can map an unknown zone more quickly and robustly than a single robot. This process is known as Cooperative SLAM (CSLAM) [4]. SLAM algorithms rely on the environment representations, maps, which consist of a set of features detectable by the robot sensory system [3]. There are three well-known map representations in SLAM, namely the occupancy-grid maps, the topological maps, and the landmark-based maps. In the case of the occupancy-grid maps, the environment is represented in a discrete grid which is composed of cells. Each cell is assigned a value which represents the probability of occupancy. Grid resolution is the key variable of occupancy-grid maps [3]. As the grid resolution decreases, average CPU-time and memory requirement needed for global localization decreases but average localization error increases. The disadvantages of occupancy-grid maps are that they suffer from discretization errors and require a lot of memory resources. Topological maps consist of vertices and edges. A vertex represents a specific place and an edge indicates the traversability between two connected vertices. Landmark-based maps store landmarks’ locations and robots’ positions in state vectors. In a two-dimensional landmark-based map, the location of a landmark is stored in the Cartesian coordinate system. A covariance matrix associated with the map is used to describe the uncertainties of landmarks’ locations and robots’ positions [4]. The memory size required to store a landmark -based map is very small comparing to an occupancy-grid map or a 3D map. This paper presents the design considerations of using a Wireless Sensor Network (WSN) as the communication means for CSLAM and investigates the potential advantages and design challenges. In CSLAM applications, robots come together at some predetermined locations to share their findings. This makes the operation slower. If communication is available all the time, then the operation may run faster. In this respect, the use of WSNs can improve communication between robots and a control center  Corresponding author. Tel: +90 284 2240283; E-mail: gurkantuna@trakya.edu.tr Please cite as: G. Tuna, V. Ç. Güngör, S. M. Potirakis, “Wireless sensor network-based communication for cooperative simultaneous localization and mapping”, Computers & Electrical Engineering, 2014, doi: 10.1016/j.compeleceng.2014.03.003