Dynamic path planning of unknown environment has always been a challenge for mobile robots. In this paper. we apply double Q-network (DDQN) deep reinforcement learning proposed by DeepMind in 2016 to dynamic path planning of unknown environment. The reward and punishment function and the training method are designed for the instability of the training stage and the sparsity of the env... https://midwaysportes.shop/product-category/tennis-balls/