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transit data bus i/o Quintuple

Bidirectional?: True

transit data bus i/o (A-Interconnect): This CVRIA application interconnect encapsulates all of the Layer 2 information flows between the 'Transit Vehicle V2V Safety' application object and the 'Transit Vehicle Databus' physical object. This application interconnect is bi-directional since the underlying layer 2 information flows carry data in both directions.

Transit Vehicle OBE (Source Physical Object): The Transit Vehicle On-Board equipment (OBE) resides in a transit vehicle and provides the sensory, processing, storage, and communications functions necessary to support safe and efficient movement of passengers. The types of transit vehicles containing this physical object include buses, paratransit vehicles, light rail vehicles, other vehicles designed to carry passengers, and supervisory vehicles. It collects ridership levels and supports electronic fare collection. It supports a traffic signal prioritization function that communicates with the roadside physical object to improve on-schedule performance. Automated vehicle location enhances the information available to the transit operator enabling more efficient operations. On-board sensors support transit vehicle maintenance. The physical object supports on-board security and safety monitoring. This monitoring includes transit user or vehicle operator activated alarms (silent or audible), as well as surveillance and sensor equipment. The surveillance equipment includes video (e.g. CCTV cameras), audio systems and/or event recorder systems. It also furnishes travelers with real-time travel information, continuously updated schedules, transfer options, routes, and fares. In CVRIA, a separate 'Vehicle OBE' physical object supports the general V2V and V2I safety applications and other applications that apply to all vehicles, including transit vehicles. The Transit Vehicle OBE supplements these general capabilities with capabilities that are specific to transit vehicles.

Transit Vehicle V2V Safety (Source Application Object): "Transit Vehicle V2V Safety" exchanges current vehicle location and motion information with other vehicles in the vicinity, uses that information to predict vehicle paths, and notifies the driver when the potential for an impending collision is detected. Information from on-board sensors (e.g., radars and image processing) are used to augment the V2V communications, if available. In addition to notifying the driver, control information can also be provided to support automated control functions that can avoid the collision. This object is similar to the "Vehicle Basic V2V Safety", but it accounts for crash scenarios that are unique to transit vehicles (e.g., Vehicle Turning Right in Front of Bus). It is also stop-aware since stop locations pose specific crash threats for transit vehicles. Finally, the detection and control algorithms, filters, and timing account for bus performance and risk profiles associated with remote vehicles that are unique to transit.

Transit Vehicle Databus (Destination Physical Object): The 'Transit Vehicle Databus' represents the vehicle databus that interfaces with on-board equipment on a transit vehicle. It is a specialized and extended form of the Vehicle Databus that is subject to different vehicle databus standards and hosts a broad range of components that are unique to a transit vehicle including the farebox and associated electronics, passenger counters, and transit security systems. As a specialized form of the Vehicle Databus, it also provides access to the general-purpose sensors (e.g., radars, cameras), GPS, drive train monitoring and control systems, and vehicle safety features that support connected vehicle applications. The Transit Vehicle may represent a bus, paratransit vehicle, light rail vehicle, or other vehicle designed to carry passengers. In CVRIA, the 'Transit Vehicle Databus' is used to represent the onboard interactions between the Transit Vehicle OBE and the other systems included in a host transit vehicle.