Research On Clustering Routing Protocols For High-Speed Robot Swarms

Mobile robot swarms perform complex tasks through the cooperation of robots and are widely used in many fields,such as military and civilian.However,the mobility of robot nodes leads to the interruption of communication chain,which brings challenges to communication and networking.Besides,the precision of the system division and the complexity of tasks also require increasing network scale and equipment diversity.Therefore,mobile robot swarms face the challenge of large-scale and heterogeneous networking.To address the above problems,this paper focuses on the routing protocol for mobile robot swarms.The main work and innovations include the following two points:Firstly,focusing on the challenges of link interruption and excessive energy consumption caused by the high mobility of the base station and nodes in mobile robot swarms,a LEACH relay routing protocol with cache strategy(LEACH-R)is proposed.In the clustering stage,inspired by the successive approximation approach,the relative rank of residual energy is defined for each node in its neighborhood and is approximatively equal to its global energy level in the whole network.According to the relative energy levels,LEACH-R selects cluster heads,which increases the probability that nodes with large residual energy are selected as cluster heads.In the relay stage,LEACH-R uses four forwarding methods:direct forwarding,cooperative intra-cluster-relay forwarding,cooperative intercluster-relay forwarding,and greedy forwarding to ensure that data packets can be transmitted to the base station through stable links.Simulation results show that compared with LEACH-M,CORMAN,RoCoMAR,and EEDDA,LEACH-R has higher packet delivery ratio,throughput and network lifetime.The paper has been published in SCI journal.Secondly,in order to solve the problem of frequent and unpredictable topology changes caused by robot heterogeneity and node entering and leaving the network at any time in large-scale heterogeneous robot swarm networks,a variable time window clustering routing protocol(VCR)is proposed.The VCR defines a variable time window and adjusts the window length according to the packet delivery ratio and the length of previous window.This enables nodes to participate in networking at different time periods,reducing the probability of congestion to ensure the applicability of the network to large-scale scenarios.Moreover,the base station selects cluster heads with strong connectivity and broadcasts the cluster head list to the whole network to reduce the impact of link instability.Simulation results show that compared with CORMAN,DOA,LBR,and p-OLSR,VCR has a significant improvement in packet delivery ratio,throughput,control overhead and average energy consumption.