Energy-Efficient Objects Collection with Tethered Mobile Robots Twins with Dynamic Grouping of Scattered Objects

This paper addresses an energy-efficient object collection problem using two mobile robots twins, equipped with a flexible tool such as a net or tether. This problem is subject to a routing problem for a collection sequence that minimizes total energy consumption of both robots for collecting scattered, multiple objects. To this end, we propose a dynamic programming-based route planning method, where the robot state is defined by energy consumption and its position. As the flexible tool allows the robots to collect a number of objects all at once, we im- plement a grouping circle of the tool, the radius of which depends on the number of the collected objects. The method incorporates a load-dependent velocity model as well as the load-dependent radius of object grouping circles to realistically reflect robot dynamics during the cooperative collection and transportation of the objects. Simulations were conducted under var- ious scenarios with different object distributions, start positions of the robots, and the maximum velocities of the robots. The simulation results demonstrate that the proposed method reduces both energy consump- tion and travel time compared to baseline methods.