Final Report March 2000
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- In-vehicle unit
- Smart cards
- Technical details
ERP OutstationAn ERP controlled point uses two overhead gantries spaced at about 15m apart and at a height of 6 m above road level. Each gantry has two antennae per lane meant to communicate with the IU by radio frequency. A set of optical vehicle presence detectors (optical line sensors) is on the second gantry to detect passage of vehicles. Two charge coupled device (CCD) cameras are placed to cover each lane on the first gantry to take the photographs of the rear licence plates of the violating vehicles. The whole set-up, which is controlled by a local controller, is termed the outstation. Each outstation is connected by telephone cables to a central computer system at the control centre. In-vehicle unitThe IU is about the size of a small pocket diary and is powered by the vehicle battery. It is fixed permanently to the right bottom corner of the windscreen by a bracket glued on by very high bond tape. The motorcycle IU which has a protective covering to prevent rainwater seeping in is fixed permanently to the front of the machine (e.g. on handlebar/fuel tank). The IU needs a direct line of sight to the antennae on the gantries for effective communication. Each IU has a back-lit LCD display that shows the cash balance in the smartcard when first inserted and when the vehicle passes a gantry point. The IUs are color-coded for different types of vehicle classes because the ERP charges may vary for them. This will also prevent the IUs from being switched around. The vehicle classes are cars, taxis, motorcycles, light goods vehicles, small buses, heavy goods vehicles, large buses and emergency vehicles. Smart cardsThe stored value smart card is issued by NETS , a company owned by a consortium of seven local banks. It is a contact smartcard and is called the CashCard. The stored value can vary from S$20 to S$500. There is a $2 deposit fee, which is refundable if the card is surrendered. The card is available at banks, post offices and petrol stations. It can be topped up at many of the automatic teller machines. The CashCard material for use in the ERP system (shown with a sun logo) is able to withstand the high temperatures (e.g. 4 to 5 hours continuously at high temperatures) experienced inside the vehicle when it is parked under the hot sun for long periods of time. Existing CashCards without the sun logo may also be used for ERP but should not be left in the IU for long periods because they will warp or melt. Technical detailsCommunication between IU and antennae is by radio frequency. Maximum speed for design is 120kph Telephone lines for communication are by Diginet and ISDN lines 11. 4. 4 Operation of the ERP When a motorist inserts a CashCard into his IU, it checks the health of the IU and the CashCard. If everything is all right, there will be a short beeping sound and the cash balance of the CashCard will be displayed for 10 seconds on the IU. A green LED will light up and remain lit until the CashCard is removed. The CashCard can be left for long periods in the IU even when the car is parked under the hot sun, but motorists have been encouraged to remove it because it is plastic money. If the system is not working when the CashCard is inserted into the IU, an ""Err" message appears on the IU display with a long beeping sound and a red LED lights up on the IU. One or more small icons may also be displayed on the IU’s LCD to indicate the type of error e.g. CashCard error, IU error. Another indication of a faulty system is a blank display. These indications mean that the IU or CashCard is faulty or cannot communicate with each other or that the IU is not getting power from the vehicle battery. Motorists are encouraged to put the system right by replacing the faulty CashCard or repairing the IU at any of the various IU installation centres before using the ERP system. At the ERP controlled point, the first gantry recognises the presence of an IU and its classification and instructs it to debit the CashCard with an appropriate amount that is determined from a table of prevailing charges for various categories of vehicles. Between the first and second gantries, the IU debits this amount from the CashCard and the driver hears a short beep and the new CashCard balance on the IU display for 10 seconds. If the IU is unable to deduct because of an error in the system or because there is no CashCard (or an invalid card) or insufficient balance in the CashCard, the driver hears a long beep, sees a red light and "Err" appears on the IU display. With an error, he may also hear the long beep and see no display. If the debiting is successful, the second gantry queries the IU and then gets such a confirmation. Meanwhile, the vehicle presence detector detects the passage of a vehicle. The antennae at the two gantries, the vehicle presence detector and the IU together with the logic in the local controller decide whether a complete successful transaction has been made. If not, there has been a violation or an error and the cameras are instructed to take a photograph of the rear license plate of the offending vehicle. Violations are committed by vehicles that have no IU, no CashCard or an insufficient balance in the CashCard to meet the cost of that passing under the ERP gantry. Errors occur when there is a faulty IU, no power to the IU from the vehicle battery, faulty CashCards and partial communications between the IU and the antennae. When a photograph is taken, the system also attaches information on why it was taken, so that technical errors and violations are differentiated. Errors do not result in prosecution. The information from the outstations on successful transactions, violation and error records and the photographs are sent periodically by telephone lines to the control centre at LTA office at Sin Ming Drive. Another smaller control centre at River Valley Road monitors the state of all outstation equipment. To ensure that a motorist is not caught unwittingly with insufficient cash balance in the CashCard, the ERP system prompts it with long beeping sounds in the IU whenever the cash balance in the CashCard falls below S$5, which will be enough for at least two more passings under the ERP gantry. The cash balance of less than S$5 remains on the IU display (unlike in normal cases when the cash balance display goes off after 10 seconds) to remind motorists to top up the cash value of the CashCard. At the end of each day, LTA sends the details on the vehicle transaction records under the gantries to the CashCard manager to claim the payment for that day. Those who commit violations are sent a notice of traffic offence (NTO) which they can settle by paying a composition fine of S$70. They can also offer an explanation or dispute the notice and get a hearing in court, as for any other offence. Those who have technical errors are sent a vehicle inspection notice (VIN) for them to turn up for an inspection. NTOs and VINs are sent out within two days of their occurrence. Directory: new new -> Nonprofit grant application new -> Bulletin 4 Monday July 8, 2002 Backgammon new -> [0] B. Hardware [2] new -> [1] B. Hardware [1] new -> Last year four of the best Afrikaans Christian singers joined forces to tour Down Under with the production ‘Manne wat Glo’ new -> The Project Gutenberg ebook of The Chronology of Ancient Kingdoms Amended new -> Management and Marketing Download 1.53 Mb. Share with your friends:
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