An Agent-Based Approach to Simultaneously Reduce Speed Limits, Lower Travel Times, and Increase Pedestrian Safety in Tallinn, Estonia

Urban road safety remains a pressing global challenge, with approximately 300,000 annual pedestrian fatalities attributed to vehicle collisions. While speed reduction is a well-established safety intervention, universal speed limit reductions can lead to negative externalities like increased travel time and pollution. To address this conflict, this study introduced an agent-based model integrating multi-agent transport simulation mobility and micro-simulation with pedestrian safety modeling for urban e-planning. Our granular analysis reveals nonlinear relationships between speed limits, safety outcomes, and travel times. Specifically, we identified instances where seemingly minor speed adjustments lead to significant and disproportionate changes in safety and travel time. Our framework provides urban planners with an anticipatory phase diagram of speed limit impacts, enabling evidence-based strategies and informed decision making. This research advances sustainable mobility planning by facilitating speed management and balancing safety and mobility within complex urban systems.