This reported work addresses a collaborative approach to path planning in continuous space for the energy constrained robot collection problem. The objective is to minimise the overall duration the mobile robots return from where the given tasks are completed. For time- and energy-efficient collection, the authors use a large-scale ground vehicle that can load and transport relatively small mobile robots. However, determining time-optimal collection locations requires too much computation in this problem setting. Therefore, a heuristic algorithm for a set of mobile robots is proposed and verified through simulations.