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Cooperative navigation for fleets of robots conventionally adopts algorithms based on Reynolds's flocking rules, which usually use a weighted sum of vectors for calculating the velocity from behavioral velocity vectors with corresponding fixed weights. Although optimal values of the weighting coefficients giving good performance can be found through many experiments for each particular scenario, the overall performance could not be guaranteed due to unexpected conditions not covered in experiments. This paper proposes a novel control scheme for a swarm of Unmanned Aerial Vehicles (UAVs) that also employs the original Reynolds rules but adopts an adaptive weight allocation mechanism based on the current context than being fixed at the beginning. The simulation results show that our proposed scheme has better performance than the conventional Reynolds-based ones in terms of the flock compactness and the reduction in the number of crashed swarm members due to collisions. The analytical results of behavioral rules’ impact also validate the proposed weighting mechanism's effectiveness leading to improved performance.

Mobile ad hoc networks (MANETs) are particularly suited for scenarios that demand rapid deployment of a communication system without any existing network resources. For instance, a MANET can facilitate the intercommunication process between members of a rescue party in a natural disaster, where the underlying routing protocol is crucial to maintaining the dissemination capability of data-critical packets. However, the backbone of every MANET, i.e., their routing protocol, is limited by the communication range of nodes, their high-speed mobility, and the capacity constraints of energy. This study proposed a fault-tolerant ad hoc on-demand routing protocol (FT-AORP) that relies on these characteristics of MANET nodes to determine reliable paths for data transmission. Subsequently, two of the discovered paths were used to transmit the duplicates of an original data packet to maximize fault tolerance. Further, using the OMNeT++ network simulator, the performance of the proposed system was evaluated through extensive simulation experiments against three simulation parameters: the number of network nodes, node speed, and data packet sending rate. The simulation results demonstrated that FT-AORP greatly improved the packet delivery ratio, reduced end-to-end delay, and maintained a higher residual energy level of the transmission path, compared to other baseline routing protocols.INDEX TERMS Mobile ad hoc network, fault tolerance, network mobility, on-demand routing protocol.