Use a battery_usage matrix to capture the battery consumption between nodes, including depot and delivery locations.
Define a maximum battery capacity (max_battery) for each drone.
Introduce dummy nodes representing recharging stops at the depot. These dummy nodes allow the drone to recharge and then resume its route.
Modify the cost and constraints to account for battery levels:
When a drone reaches a dummy node, its battery resets to max_battery
.Create a dimension to track battery usage:
routing.AddDimensionWithVehicleCapacity( battery_consumption_callback, slack_capacity, # Optional slack max_battery, # Maximum battery capacity True, # Start cumulative battery at 0 'Battery'
.Use a callback to compute battery consumption between nodes.
.Add a constraint to check battery levels after each delivery: def battery_constraint(manager, routing, battery_dim): for vehicle_id in range(num_vehicles): index = routing.Start(vehicle_id) while not routing.IsEnd(index): battery_var = routing.CumulVar(index, battery_dim) next_index = routing.NextVar(index) routing.solver().Add( battery_var >= battery_consumption_callback(index, next_index) ) if battery_var < min_battery: # Threshold for recharging routing.solver().Add(next_index == depot_index) index = next_index
5.Resume Tasks After Recharging
.Ensure the drone continues its route after visiting the depot: .Use the sequence of delivery locations to define precedence constraints. .Use the nextvar method in OR-Tools to maintain continuity
routing.solver().Add(routing.NextVar(depot_revisit) == next_delivery_node)