AUV-USV Mobile Charging

The mission employs AUVs capable of reaching a maximum speed of 3 km/h for 12 hours, incorporating a safety margin of 2 hours. USVs, on the other hand, are bound by a speed limit of 16 km/h, and each rendezvous necessitates an 8-hour battery charging process. Our objective is to minimize the overall mission time, and optimized trajectories of AUVs and USVs through Algorithm 1.

Algorithm 1. Dijkstra-GA AUV Mobile Charging

UAV-USV Time-Sequence Charging

The mission utilizes UAVs with two distinct flight modes: Work mode and Travel mode. During the Work mode, the UAV explores the area at a speed of 20 km/h, while in Travel mode, it flies to the start point or charging stations at a speed of 60 km/h. Each flight is limited to a maximum of 0.7 hours to ensure it doesn't exceed the battery capacity. After 0.5 hours of work, the drone heads to the charging stations. Each USV can charge a maximum of two UAVs simultaneously, and the charging process takes 2 hours.

Our goal is to minimize the overall mission time and return distance for charging by the Algorithm 2. The mission involves three UAVs covering the same square area. The previous USV rendezvous points serve as time-sequence charger stations, marked by green and orange crosses. The black crosses indicate interruption points where AUVs need to return for charging.

Algorithm 2. GA UAV Time-Sequence Charging

How to Run the Code

Stage1 AUV planning

1. "stage1_auv" includes the below codes and save "auv_mobile_charger_yyyy-mm-dd_HHMMSS.mat"
   • "stage1_auv_planner" is to run the GA
   • "stage1_auv_plot_path" is to plot the AUV-USV path
2. "stage1_auv_plot_battery " is to plot the AUV-USV batteru schedule and save "asv_travel.mat"

To run the record data:

1. Read the previous data, press F9 in line 327 of "stage1_auv"
   • load('auv_mobile_charger_2024-01-17_162755.mat');
2. Plot the AUV-USV path, press F9 in line 332 of "stage1_auv"
   • [traj_segment,time_given_charger, traj_worker_nth] = stage1_auv_plot_path(a,userConfig.numTarChargers,userConfig,start_point,start_pCharger,G,start_node_th,points_to_remove);
3. Run "stage1_auv_plot_battery " is to plot the AUV-USV batteru schedule

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Stage2 UAV planning, UAV battery life is 0.4 hour

1. "stage2_uav" includes the below codes and save "uav_time_sequence_charging_yyyy-mm-dd_HHMMSS.mat"
   • "stage2_uav_planner" is to run the GA
   • "stage2_uav_plot_path" is to plot the UAV-USV path
2. "stage2_uav_plot_battery " is to plot the UAV-USV battery schedule

To run the record data:

1. Read the previous data, press F9 in line 229~230 of "stage2_uav"
   • load('uav_time_sequence_charging_2024-01-20_051116');
   • load('asv_travel.mat');
2. Plot the UAV-USV path, press F9 in line 236 of "stage2_uav"
   • [traj_segment] = stage2_uav_plot_path(a,userConfig.numTarChargers,userConfig,start_point,start_pCharger, asv_xy);
3. Run "stage2_uav_plot_battery " is to plot the UAV-USV battery schedule