A deep reinforcement learning framework with generalization performance for the large-scale capacitated vehicle routing problem

Combinatorial optimization has found its way into a variety of domains, including artificial intelligence and cybernetics. Deep Reinforcement Learning (DRL) has recently demonstrated its promise for developing heuristics for NP-hard routing problems. The current generalization performance of models needs to be improved, especially for large-scale routing problems. In this paper, we propose a hybrid approach for the Capacitated Vehicle Routing Problem (CVRP) based on DRL and adaptive large neighborhood search. The information representation of the neural network for CVRP is also improved by the combination of multi-head attention mechanism, pointer network and graph neural networks. The experimental results demonstrate that the optimization of our model on CVRP outperforms existing DRL techniques and some traditional algorithms. In addition, our method improves the training efficiency of the model and the performance of generalization to large-scale CVRP.