Bottleneck Simulation with Cellular Automata Model

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Bottleneck Simulation with Cellular Automata Model

• Justin Findlay
• Peter Berg

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Road Traffic Fundamental Diagram

• qq(?)

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CA Model Discrete in Space Time

• Optimum Speed
• Update Rules

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Bottleneck Periodic Boundary Conditions
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Fundamental Diagram

• Open Road

Bottleneck
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Fundamental Diagram
Possible stationary wave solutions with 2 or 3
shocks
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Computing A Wave Solution

• Given Want
• 2 Unknowns, 2 Equations
• Conservation of cars
• Wave speed is zero
• This allows for all of the wave solutions from
  the previous diagram. However, we only observe
  the first two of these plus the trivial solution.

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Results ? 0.17
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Results 0.17 ? 0.25
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Results ? gt 0.25
Note The fact that we can only observe 3 wave
solutions might be explained by the dynamic wave
theory of the similar ODE model.