R58

R58 / Mc:Mc-1

Turn Movement yields to traffic from zero, one or many Angular Intersection Entrance Lane

Turn Movement flows priority traffic across _ zero, one or many_ Angular Intersection Entrance Lane

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Consider an unprotected inside turn crossing in front of oncoming traffic. The Ego Vehicle must yield to any such vehicles because the turn is unprotected. But where does this oncoming traffic originate? It must come from some Entrance Lane in some Road Segment other than that of the Ego Vehicle.

What if the inside turn is protected sometimes and permissive (unprotected) at a different part of the signal phase? The yield requirement is still modeled, but it just won’t be active during the protected time period. The notion of active/inactive can be determined by the overall status of the associated Turn Movement.

In practice, this concept will apply only to inside turns, but there is no reason why it couldn’t apply to an outside turn if, for some reason, outside turning traffic is required to yield to traffic coming from some other direction.

In the case of a fully protected turn with no permissive component, there will be no yield requirement. The Ego Vehicle will always have priority in the turn. A given Entrance Lane may or may not flow priority traffic against a Turn Movement from another Entrance Lane. And it is even possible for an Entrance Lane to flow priority traffic against multiple Turn Movements, say both an inside turn and an inside u-turn.

Formalization

Oncoming Traffic Yield Requirement.(EL road segment, EL inside division, Exit conduit road segment, Exit conduit, Intersection) ->
    Turn movement.(EL road segment, EL inside division, Exit conduit road segment, Exit conduit, Intersection)
Oncoming Traffic Yield Requirement.(Oncoming lane inside division, Road segment) -> 
    Angular Intersection Entrance Lane.(Inside division, Road segment)