Vehicle Routing for Collaboratively Collecting Disaster Area Information

The emergency disaster response headquarters (HQ) is responsible for incrementally collecting disaster information on the whole area in a region. Our previous work studied a routing problem for patrolling vehicles to monitor such information along all streets and bring it to HQ multiple times on the way individually. The optimal routes for vehicles can be found by a systematic search so as to minimize the average delay time in incremental information collection. Further, we have also studied an area-segmentation approach in which each vehicle only collects the information in one sub-area. However, in such individual collection approaches, multiple (duplicated) transits on the same street by vehicles could happen frequently in general because each vehicle must return to HQ every time it brings the monitored information by itself for incremental collection. Therefore, this study explores a collaborative collection scheme where multiple vehicles work together instead of each vehicle bringing its own monitored information to HQ individually. In the proposed scheme, a vehicle can drop off the monitored information at a Pickup Point (PP) on the way rather than HQ. Then, another vehicle passing the PP picks up the stored information and brings it to HQ. This scheme helps to reduce the time taken to collect information by multiple vehicles because it can increase the amount of information brought by a single return to HQ at the expense of the deployment cost of PP. We also provide a systematic search to find the best routing for the collaborative collection scheme. Our simulation results indicate that two vehicles collaborating on information collection with only a single PP can clearly reduce both the average delay time in incremental collection and the completion time to collect all information, compared with those working individually.