lanelet2_traffic_rules

Package for interpreting traffic rules in a lanelet map

• Links

  • Repository

• Standard Documents
  • CHANGELOG
  • PACKAGE
  • README

README

Lanelet2 Traffic Rules

This package provides functionality for interpreting the traffic rules in a lanelet map depending on a country and a traffic participant.

It contains functionality to determine right of way, speed limits and legally reachable lanelets for a certain participant.

Usage

#include <lanelet2_traffic_rules/TrafficRulesFactory.h>
lanelet::traffic_rules::TrafficRulesPtr trafficRulesPtr =
  lanelet::traffic_rules::TrafficRulesFactory::create(lanelet::Locations::Germany, lanelet::Participants::Vehicle);
bool passable = trafficRulesPtr->canPass(myLanelet);
lanelet::traffic_rules::SpeedLimitInformation speedLimit = trafficRulesPtr->speedLimit(myLanelet);

Structure

This package offers the abstract TrafficRules class that is used as an interface to interpret the data in the map. It provides information whether a lanelet is usable/drivable, where lane changes are possible and what the speed limits are.

Derived from this is the abstract GenericTrafficRules class that implements the traffic rules based on the tagging specification. This class can then be derived to create traffic rules for individual countries and participants. This is especially important for the speed limits and interpreting country specific traffic signs.

After registering this class using RegisterTrafficRules, Lanelet2 is able to create instances of this traffic rule using the TrafficRuleFactory.

Hierarchical Structure of Participants

Some classes of participants, especially vehicles, follow a hierarchical structure. A traffic rule class that is registered for an upper level of this class is expected to handle all specializations for this class. For example if a TrafficRules implementation is registered for vehicle, it can also be instanciated for vehicle:car, but not vice versa.

When lanelets/areas have tags for specialized participants, e.g. have “participant:vehicle:car=no”, the TrafficRule class must handle this appropriately. If these tags are too specialized for an instance, the result should be as conservative as possible. This means that if a TrafficRule instance for vehicle finds a participants:vehicle:car=no and participants:vehicle:bus=yes, the lanelet is not passable.

However if it was instanciated for vehicle:bus instead of just vehicle the lanelet would be reported as passable.