The cluster space control technique promotes simplified specification and monitoring of the motion of mobile multi-robot systems of limited size. Previous work has established the conceptual foundation of this approach and has experimentally verified and validated its use for two diverse 2- robot systems and with varying implementations ranging from automated trajectory control to human-in-the-loop piloting. In this paper, we present the cluster space control of a 3-robot system. In doing so, we develop the fundamental kinematic relationships, illustrate the closed-loop control framework, describe the simulation and hardware testbed environments used for verification, and present initial experimental results of the successfully implemented system.