In a fully automatic system, the vehicles are processed without the need of a toll booth operator. In this case, the road user carries money electronically in a pre-paid storage media like smart card or OBU (on-board unit). In case of smart card transactions, the vehicles will have a prepaid plastic smart-card which will be read by an electronic smart-card reader fixed to the driver?s side of the toll lane. The user will show the card to the reader and pass. The display unit will show the user about successful transaction of the fee and permit the passage. In case of OBU transaction, there is no need for the vehicle to stop at the toll booth. The vehicle has an on-board unit or ?tag? installed on its windshield which communicates to the ?reader? mounted at a height on the specified toll lane. The tag or OBU contains vehicle, credit and other information stored in it, and communicates with the reader over wireless or infra-red. The reader (along with the computer system) instantly validates the tag remotely, deducts passage fee and gives command to the system to lift the barrier to allow passage. This is also called Electronic Toll Collection (ETC) system. Some countries also have ?barrier-less tolling? where there is no toll plaza and the ETC readers are mounted on a gantry constructed over the carriageway. If a vehicle with invalid card (tag or OBU) or credit tries to pass, a License Plate Reader (LPR) camera records the image of vehicle registration plate and the vehicle owner is sent a ticket by post. Smart cards usually work up to 10cm and are suitable for ?touch and go? applications. OBUs or tags work up to several hundred metres (depending on technology and power) and are ideally suited for high speed and ?free flow? applications.
One such application which deserves special mention is interoperable electronic toll collection (ETC) system, as this is now being implemented in India by NHAI. ETC consists of a tag or transponder fitted on a vehicle which is read by a reader or ?interrogator? installed in a toll lane. The tag is linked to a user account. As the vehicle passes through an ECT enabled toll lane, the tag and reader exchange data, the user account is debited for toll fee and the vehicle is allowed to pass without having to stop. The tag-reader communication can be through various communication methods like radio frequency identification (RFID), microwave and infrared waves. The RFID standard (860-950 MHz frequency) gained popularity in North America while Europe adopted 5.8GHz microwave standard, both being specific to tolling. The USA is now moving away from RFID standard towards a standard called WAVE (Wireless Access for Vehicular Environment). This standard is designed for general internet access and can support many applications, ETC being one of them. Also, as compared to RFID, it supports much larger read ranges (up to 1,000m), and up to 25 times faster data communication, higher channel capacity. Also, it uses open off-the-shelf chipset and software and can support V2V communication as well. NHAI has opted for RFID standard with 865-869 MHz frequency as it is considered to be more suitable for India.
Weight enforcement systems
In such applications, the axle weight of a moving vehicle is measured by sensors embedded or fixed on the road. In the PPP projects, NHAI has now mandated compulsory installation of weigh-in-motion (WIM) scales in each toll lane. In case of violation, such vehicles shall be guided to a Static Weigh Bridge (SWB), one at each exit side of the toll plaza. The WIM filters the overloaded vehicles, and in case the Gross Vehicle Weight (GVW) exceeds permissible limit, the vehicle GVW is measured on SWB for accurate measure and verification for appropriate enforcements. In some projects, there is a provision to charge higher fee from overloaded vehicles, and in any such case, the overloaded vehicle has to offload excess load before being allowed to proceed on the highway. Prevention of overloading is important not only from the safety perspective but also because of the damage it causes to the road, which in turn results in higher maintenance costs leading to national wastage.
In the applications of ATMS (or HTMS), various subsystems are integrated and connected to a Central Control Room (CCR). The subsystems are (a) Emergency Call Booth (ECB) installed every 2km on either side of the road for the road user to connect to the CCR for help or advisory, (b) weather stations to record weather information like visibility, temperature, wind speed, etc., (c) cameras to monitor the highway (for incident detection) (d) automatic traffic counter cum classifiers (ATCC) to gather traffic information for audit and planning, (e) gantry mounted variable message signs (VMS) to disseminate information to road users, and (f) mobile radio system (walkie-talkies) for use by emergency response vehicles. All these roadside subsystems are connected over optic fiber link to the CCR. The Control Room Operators (CROs) monitor the highway round the clock and provide assistance to the road user.
Challenges for India
ITS so far had a limited application in India and the efforts have been less focused and integrated, and there have been several reasons for this. Firstly, most ITS initiatives need to be supported by legal framework and enforcement measures. For example, weight enforcement is still not much successful even though weighbridges are now required on almost every tolled highway. Secondly, lack of an ITS standardisation body in India means that each agency implements ITS in its own way. This fragmented approach means higher costs, very little interoperability and inefficient reporting. Thirdly, the implementation in the highway sector is driven more by NHAI stipulations, rather than being customer driven. This has resulted in implementations which are not working in true sense in any of the projects, and have given little benefits to the road users. Fourthly, it needs to be internally driven. Government agencies like NHAI can stipulate some minimum norms, but implementing agencies need to make it all work on ground with best industry practices. At the same time, lack of industry effort towards cooperation in the area of ITS indicates that it has not yet gained the importance it deserves. Finally, there are other factors that affect ITS implementation in India such as shortage of skilled manpower and training facilities, limited investment in research, shortage of Indian suppliers and lack of a comprehensive system to review and appraise the effectiveness of ITS.
Road Ahead for ITS in India
In spite of the challenges, the road ahead is full of opportunities. This is partly due to the uniqueness of Indian transportation needs and partly due to the technology gap that exists between India and the developed economies. Curre
ntly the country is undergoing rapid growth in the development of high speed road n
etwork including expressways. The role of ITS becomes increasingly important as these newly constructed roads opened for traffic have also shifted the focus from construction to operations and maintenance (O&M). The growth of ITS shall not only be driven by business opportunities but also by the demand for improved services by the road users. The future ITS components shall not only collate huge amounts of data but shall also have the capability to be interconnected and be interoperable.
The massive amount of information shall be analysed, processed and used to service road users which in turn would spur growth in the other services of road infrastructure segment. The information could be used for analysing accident data for improved safety; monitoring driver behaviour for designing better roads and intelligent vehicles; vehicle volume and location tracking data could be used to determine driving preferences for road pricing; data from interconnected, interoperable and cooperative highways shall help in tracking violators and their behaviour; monitoring road user complaint and feedback data would help make better roads and improved services.
In summary, ITS can help build not only better roads and services, but is also helpful for development of better vehicles and transportation systems. ITS indeed has the potential to be a game changer for the Indian highway infrastructure industry.
Prof P K Sikdar (President, Intercontinental Consultants & Technocrats Pvt Ltd New Delhi) has more than 30 years of experience in the field of traffic and transportation. He has been Professorand Dean at IIT Bombay and Director, CRRI. He has worked on many prestigious projects of the country like Delhi Metro and Bandra-Worli Sea Link. Puneet S Bindra(Vice president, Intercontinental Consultants & Technocrats Pvt Ltd New Delhi) has 20 years of experience in the field of electronics & telecom, and specialises in the area of ITS on highways. He has also worked extensively on toll systems, ATMS and weight enforcement systems.