A Systematic Literature Review on UAV-Assisted Path Planning for UGVs in Heterogeneous Multi-Robot Systems

Autonomous mobile robotic systems are increasingly deployed in unstructured and unknown environments. In such settings, effective mapping and path planning remain critical challenges for unmanned ground vehicles (UGVs), particularly due to their limited perception from a ground-level perspective. In contrast, unmanned aerial vehicles (UAVs) offer enhanced situational awareness through their high mobility and wide field of view. This systematic literature review investigates how multi-robot systems (MRSs) utilise aerial mapping to enhance ground-based path planning. The selected studies are analysed concerning application domains, environmental conditions, and performance objectives. In addition, the study examines technical solutions, including mapping techniques, exploration methods, coordination, data processing and transfer, and path planning methods. The review highlights that domains such as industrial shop floors remain underrepresented among the application areas. A key contribution of this work is the derivation of two morphological boxes for use case classification and system design, providing a structured framework for future MRS implementations. Their exemplary application to industrial shop floors addresses this gap and illustrates how MRSs can support smart manufacturing.