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Tolling
| Applications | |
|---|---|
| Title | Tolling |
| Author(s) | Rui Barradas Pereira. |
| Level | Basic |
| Year of Publication | 2011 |
It is foreseen that traditional ways of road tolling will be substituted by solutions based on positioning by means of GNSS[1]. On the other hand there's the need of implement urban tolling that is usually called Congestion Charge Zone (CCZ) with the aim to avoid urban pollution and urban traffic congestion. The use of GNSS for Electronic Tolling Collection (ETC) has many advantages with respect to other technologies as it allows for a flexible and scalable system with minimum specific roadside infrastructure. This translates directly into a simple and cost efficient system. In fact, the interoperability directive 2004/52/EC adopted by EU in 2004 prescribed the development and deployment of a European Electronic Tolling Service (EETS), recommending the GNSS technology as the one to be adopted[2].
Road and urban tolling based on GNSS implies that the position and trajectory of a vehicle is determined using GNSS in order to decide if the vehicle must be charged or not and to compute the charging value. This must be done along with the determination of an accuracy level and the acquisition/generation of some kind of irrefutable evidences that can prove the amount of applied charges.
Application Architecture
ETC applications are implemented using On Board Units (OBUs) developed for that specific purpose that use GNSS data to compute the charging values. Some also integrate with additional sensors such gyroscopes, accelerometers or OBD input data to minimize the effect of positioning errors may have in collecting incorrect charges and, in particular, to prevent the charging of vehicles that are not using the road or urban area subject to toll.
In general these OBUs rely on Satellite Based Augmentation Systems (SBAS) like EGNOS or WAAS achieving better accuracy and making decisions based on the integrity, reliability and availability provided by those systems. There are also devices equipped with built-in autonomous algorithms that handle and decrease the effects of local errors, such as non-line-of-sight multipath. These kinds of mechanisms guarantee an acceptable protection level (PL) for a ETC system dismissing the use of additional sensors that would add complexity and cost to the systems.
System Architecture (Thin Client vs. Fat Client)
Application Characterization
The goal of this kind of application is having an “error-free” charging computation which will make this application acceptable by institutions and users and with high utility value. Providing integrity of the computed position allows ensuring that vehicles are not charged incorrectly. This is done establishing a threshold value for the position protection level, i.e. if a computed position corresponds to a protection value that exceeds the threshold value that position it will not be used to compute charging values.
From the user point of view tolling application will be working in a transparent way since the user doesn’t have to operate the OBU that are installed on its vehicle. Eventually the user receive a monthly detailed report justifying the charged amount.
Charging Schemes (Distance based, Cordon)
Application Examples
The main tolling applications providers are[3]
- Intelligent Mechatronic Systems: Has developed the DriveSync® product which is a modular vehicle telematics system that uses Global Positioning System (GPS) and cellular technologies to track vehicles.
- GMV: Developed the allroadTM product which is a standalone OBU which guarantees a 99,99% of reliability bellow the established protection level (22 m in open sky environment and 75 m in urban environment).
- Satellic: Developed platform makes it possible to implement flexible road toll solutions based on free-flow-systems.
- Skymeter: Has developed an OBU that is installed along with an LCD display to show the charged tool and some other informations.
- Toll Collect: Has developed and is running the toll billing system for trucks (LKW-MAUT) on German motorways.
- Kapsch TrafficCom: On-board units are read/write devices designed to ensure high data security and integrity with high speed internal processing
- EFKON: The OBU autonomously determines the position of the vehicle, identifies road sections subject to toll according to predefined rules, calculates the charge if required inside the OBU, and transmits the result to the toll centre
- Siemens VDO: A hybrid OBU (on-board unit) in the vehicle manages both microwave and satellite-based toll systems
Notes