Multi-Centralized Cooperative Localization under Asynchronous Communication

In this report we present an overarching framework for inter-robot information transfer schemes in Multi-Centralized Cooperative Localization (MC-CL) under asynchronous communication, i.e., when the communication graph associated with the mobile robot network is time-varying and intermittently disconnected. Specifically, two information transfer schemes, that differ based on their communication bandwidth requirements, are discussed. Even under asynchronous communication constraints, these schemes enable robots to compute pose estimates identical to those generated using the centralized CL framework, albeit delayed. For each of these schemes, necessary and sufficient conditions for the communication graph connectivity, that enable each robot to generate the centralized estimates, are developed. Moreover, detailed description of these schemes, along with their communication complexity analysis and analytical results for the expected time delay in obtaining these estimates, are presented. Lastly, extensive simulation results are used to validate the performance (the trade-off between communication bandwidth and accuracy/delay) of these information transfer schemes.