A Damage-Tolerant Task Assignment Algorithm for UAV Swarm in Confrontational Environments

Algorithm 1

Primary Copies Assigning in DTTA.

1 Get p_i of arrival task t_i^P;

2 Let in U that satisfies task t_i’ demands;

3 foreachu_j in do.

4  Calculate the distance d_ij between task t_i and UAV u_j;

5 Sort in an increasing order by the value of d_ij;

6 U_candidate ⟵ top α% UAV in ;

7 AllocateTag ⟵ FALSE; FT ⟵ +∞; u ⟵ NULL;

8 while!all u_j∈Uhas been scanneddo.

9  OverlapTag ⟵ TRUE;

10  foreachu_j in U_candidatedo.

11   ifu_j’s assigned last task can be overlapped then.

12    Calculate EFT_j(t_i^P) in overlapping mode;

13    ifEFT_j(t_i^P)<FT & EFT_j(t_i^P) <td_ithen.

14     FT ⟵ EFT_j(t_i^P);

15     u ⟵ u_j;

16  foreachu_j in U_candidatedo.

17   Calculate EFT_j(t_i^P) in non-overlapping mode;

18   ifEFT_j(t_i^P)<FT & EFT_j(t_i^P) <td_ithen.

19    OverlapTag ⟵ FALSE;

20    FT ⟵ EFT_j(t_i^P);

21    u ⟵ u_j;

22  ifu is not null & t_i^B can be scheduled & OverlapTag = TRUEthen.

23   AllocateTag ⟵ TRUE;

24   Assign t_i^P on UAV u in overlapping mode;

25   generate backup copy t_i^B based on FT;

26   schedule t_i^B;

27   break;

28  ifu is not null then.

29   Assign t_i^P on UAV u in non-overlapping mode;

30   AllocateTag ⟵ TRUE;

31   ife_ti > et_thresholdthen.

32    generate t_i^B based on FT;

33    schedule t_i^B;

34   break;

35  U_candidate ⟵ next top α% UAV in ;

36  ifallocateTag ⟵ FALSEthen.

37  Reject t_i^P;