Decentralized Multi-Robot Task Allocation Under Degraded Communication: A Benchmark of Performance, Reliability, and Computation
Organizations: Department of Electrical Engineering, University of San Diego, San Diego, CA 92110 USA
Abstract
Selecting a decentralized Multi-Robot Task Allocation (MRTA) method for embedded deployment on autonomous platforms requires considering more than route performance alone. We benchmark six decentralized MRTA allocators (CBAA, ACBBA, PI, HIPC, DMCHBA, and DGA) in the Collaborative Visit (CV) scenario to characterize tradeoffs among MinMax and MinSum travel, communication robustness and demand, allocation reliability, computational burden, and scale sensitivity. The core study uses 500 paired ten-target instances across 25 ideal and degraded communication conditions spanning Bernoulli loss, Gilbert--Elliott loss, and Rayleigh fading, with additional campaigns examining pre-allocation, execution-integrated computation, and sensitivity to grid size, robot density, and target load. Across the 24 impaired core conditions, DGA and DMCHBA achieved the lowest mean MinMax travel at 24.49 and 24.78 steps, respectively. HIPC narrowly led mean MinSum travel at 66.95 steps, followed by DGA at 67.22, with both methods occupying the top two in every impaired condition. DMCHBA had the lowest publication intensity at 2.08 publications per team step. In ten-target pre-allocation, HIPC and DMCHBA remained viable and stable in every tested condition, while ACBBA, PI, and DGA lost stability or viability as communication degraded. Under ideal delivery, median full-protocol computation in the primary ten-target comparison ranged from 4.88 ms for DMCHBA to 1.346 s for DGA. Static route quality preserved DGA and DMCHBA as the leading MinMax methods, while DGA led MinSum at three of four target loads and HIPC led at 50 targets. Static and execution-integrated computation rankings diverged as task load increased. The results identify distinct allocator operating regions across route objective, communication behavior, reliability, and computational constraints.
Figures & tables
| Dimension | Nayak et al. [ 5 ] | Cao et al. [ 6 ] | This work |
| Algorithms | CBAA, ACBBA, DHBA, HIPC, PI | CBAA, CBBA, DHBA, HIPC, PI, DGA | CBAA, ACBBA, PI, HIPC, DMCHBA, DGA |
| Execution | Repeated allocation and communication at a common 0.1-s cadence | Synchronous pre-allocation and periodic asynchronous dynamic allocation | Event-driven mission execution with separate strict-barrier pre-allocation and execution-timing studies |
| Communication | Bernoulli, Gilbert–Elliott, and Rayleigh fading | Packet loss, bit errors, and one-hop delay | Bernoulli, Gilbert–Elliott, and Rayleigh fading |
| Design | 50 randomized trials per principal condition | 100 Monte Carlo trials at two agent–target scales | 500 paired core instances per condition with separate paired pre-allocation, execution-timing, and scale-sensitivity campaigns |
| Outcomes | MinMax travel and maximum-agent messages | MinMax path quality, allocation reliability, payload-aware overhead, and runtime | MinMax and MinSum travel, duplicate work, workload concentration, communication demand, allocation reliability, static and execution-integrated computation, and scale continuity |
| Method | Planning scope | Local allocation mechanism | Allocator communication and repair |
| CBAA [ 13 ] | One current target | Highest locally feasible distance-based bid | Delta winner–bid records, deterministic tie breaking, and rebidding after ownership loss |
| ACBBA [ 14 ] | Ordered bundle | Marginal route-insertion bids | Timestamped delta deconfliction and release of a lost target with its dependent suffix |
| PI [ 19 ] | Ordered path | Marginal route significance, with lower significance preferred | Owner, significance, and path records with local removal and rescoring after ownership loss |
| HIPC [ 20 ] | Local team plan | Greedy planning over the local robot and predictable peers | Path claims, prediction checking, stale-claim cleanup, and neighborhood pruning after repeated mismatch |
| DMCHBA [ 26 ] | Clone-expanded assignment | Hungarian matching followed by local route ordering | No allocator-specific bid or assignment messages, with allocation reconstructed from locally available team state |
| DGA [ 28 ] | Complete team plans | Population search with selection, crossover, mutation, repair, and elitism | Changed owner-route information is exchanged and valid received plans enter the local population |
| Campaign | Algorithms | Conditions | Sampling | Purpose |
| Asynchronous core | Six | Ten targets under ideal delivery and 24 degraded communication conditions | 500 per condition, 112,500 unique simulations | Realized travel, communication, coordination, and degradation response |
| Synchronous pre-allocation | Five multi-task methods | 5, 10, 25, and 50 targets under selected ideal and degraded treatments | 50, 100, 50, and 25 per condition, 4,500 trials | Viable and stable allocation, , and achieved route quality |
| Asynchronous computation | Six | 5, 10, 25, and 50 targets under ideal delivery | 1,350 primary records plus 675 objective-specific checks | Execution-integrated computation and allocator-call frequency |
| Scale sensitivity | Six | Grid-size/robot-density sweep and fixed-grid target-load/robot-count sweep | 14,400 grid/density simulations plus 3,200 target/team simulations | MinMax and MinSum ranking continuity across scale |
| Method | Leads | Top two | ||
| CBAA | 26.02 | 0 | 0 | 5.19 |
| ACBBA | 26.91 | 0 | 0 | 3.71 |
| PI | 29.05 | 0 | 0 | 2.48 |
| HIPC | 25.12 | 4 | 8 | 2.61 |
| DMCHBA | 24.78 | 2 | 19 | 2.08 |
| DGA | 24.49 | 18 | 21 | 3.38 |
| Method | Viable /100 | Stable /100 | (ms) | MinMax | MinSum |
| ACBBA | 100 | 98 | 86.62 | 40.0 | 61.5 |
| PI | 97 | 70 | 166.06 | 48.0 | 56.0 |
| HIPC | 100 | 100 | 52.65 | 40.0 | 51.5 |
| DMCHBA | 100 | 100 | 4.88 | 22.5 | 70.0 |
| DGA | 100 | 100 | 1345.60 | 21.0 | 50.0 |