Abstract:
Urea supply information with is integrated with vehicle location, routing and urea consumption information to generate driver guidance for obtaining urea resupply or, at a minimum, automatically generating orders to position supplies of urea at a target location.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Technical Field 
         [0002]    The invention relates to vehicle telematics and more particularly to providing routing and scheduling of vehicles for replenishment of urea required for exhaust after-treatment on some diesel engine equipped vehicles. 
         [0003]    2. Description of the Problem 
         [0004]    Diesel engine equipped highway vehicles will, beginning in 2010, be required to meet tightened emission standards in the United States. One after-treatment technology developed to reduce emissions from diesel engines, selective catalytic reduction (SCR), requires urea. The United States Environmental Protection Agency has mandated that vehicles be disabled if the diesel pollution control system is not operative. Exhaustion of the on-board urea supply on SCR equipped vehicles would be a condition requiring making a vehicle inoperative. 
         [0005]    There is a need to insure the reasonable availability of urea to allow operators of commercial vehicles to replenish on board supplies of urea where little extant urea distribution infrastructure exists. Barton and Lonsdale writing for the Diesel Engine Emissions Reduction (DEER) conference of 24-28 Aug. 2003 stated that urea costs would be dominated by distribution costs and not primarily be production or raw material costs. With urea consumption in liquid measurement terms equaling about 5% of fuel consumption a 25 gallon urea tank would support a range of 3,250 miles on a vehicle achieving an average fuel economy of 6.5 miles per gallon, typical for a heavy duty truck. Replenishment of urea at locations close to production facilities to minimize its cost promises some cost savings. However, it is possible that development of a urea distribution system is being depressed by the possibility that technological developments may render obsolete urea based SCR systems. 
         [0006]    If a vehicle must be removed from service awaiting replenishment of urea its owner may incur substantial costs due to unavailability of the vehicle and the need to arrange an emergency delivery of urea to the vehicle. It would be advantageous to anticipate the need to replenish the supply, and be able to efficiently route the vehicle near existing supplies, pre-schedule replenishment and/or preposition supplies to minimize down time of vehicles. 
         [0007]    The assignee of the present invention operates the International Aware Vehicle Intelligence system, an enhanced vehicle telematics system providing vehicle performance tracking, diagnostic functions and mapping capabilities through a mixture of on-board and off-board electronics. Owners of vehicles may subscribe to the system. The off-board electronics include wireless communications systems and the global positioning system (GPS). 
       SUMMARY OF THE INVENTION 
       [0008]    For a vehicle equipped with an internal combustion engine and an SCR exhaust after-treatment system using urea, the invention integrates available urea supply information with vehicle location, routing and urea consumption information to generate driver guidance for obtaining urea resupply or, at a minimum, automatically generating orders to position supplies of urea at a target location. A positioning information system provides current vehicle location. The vehicle tracks fuel consumption and urea tank fill levels. This data is reported over a communication link to a central data processing server which can access current and projected availability of urea along likely routes and return the data to the driver of the vehicle. 
         [0009]    Additional effects, features and advantages will be apparent in the written description that follows. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]    The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself however, as well as a preferred mode of use, further objects and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, wherein: 
           [0011]      FIG. 1  is a schematic of a telematics systems adapted for data condition data collection and integration system for enhancing commercial vehicle in service time. 
           [0012]      FIG. 2  is a block diagram of a vehicle controller area network control system adapted for use in the data collection and integration system of  FIG. 1 . 
           [0013]      FIG. 3  is a simplified flow chart related to vehicle identification and routing for urea replenishment. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0014]    Referring now to the figures and in particular to  FIG. 1 , a generalized vehicle telematics system  100  emphasizing central support for vehicle management is illustrated. Vehicle telematics system  100  may be implemented using one, or more typically, a large plurality of vehicles represented by vehicle  102 , which communicate with a manufacturer&#39;s or vehicle operator server  114  using any convenient means. The linkages are typically implemented over a cellular telephone link  108  to link with a cellular base station  112  or short range RF link. 
         [0015]    Vehicle  102  includes an electronic control system based on a controller area network (CAN) system  104 . Controller area network system  104  links numerous controllers onboard commercial vehicle  102  for data communication and allows central activation and control of remote data communications services as through cellular phone link  106  and use of services such as global positioning using a global positioning unit  108  reading GPS satellites  110 . 
         [0016]    Cell phone base station  112  is linked by land lines including, if advantageous, internet services, for the transfer of data from cell phone link  108  to a server  114 . The data from the vehicle  102  can include, as set forth in detail below, information relating to engine loading, extreme brake use and other vehicle operating variables collected by the CAN system  104 . Records forwarded from vehicle  102  are time, date, location and mileage stamped. Data can be forwarded from a vehicle over a cell phone link by connection  115  (such as short range RF or direct hand wire connection) to server  114  which accesses statistical processing services  124  for determination of projected duration of the urea supply based on its historical relation to fuel consumption for the vehicle  102 . Data bases  128  including geographic information systems can be accessed to project fuel consumption based on routing of the vehicle (if available) and to update the list of urea supply points for uplink to the driver on board the vehicle  102 . Server  114  maintains a website with pages for each vehicle  102  which may include a map with the vehicle&#39;s location and notations as to the locations of supplies of accessible urea supplies, emphasizing supplies located along the vehicle&#39;s projected route. 
         [0017]    Server  114  maintains databases of vehicle statistics indexed by mileage on databases  128  and the availability of urea at geographically distributed urea service facilities  190 . These records allow in urea use trends to be detected by comparison operations  124  with the results being placed on a secured page on website  122  for the use of management. 
         [0018]    Referring now to  FIG. 2 , the features of a controller area network system  104  such as used on vehicle  102  are set out. Controller area network  104  has as a foundational element a programmable body computer  230  based on a microprocessor  272  and memory  274 . Memory  274  may in turn include both volatile and non-volatile sections (not shown). Microprocessor  272  communicates with other parts of the programmable body computer  230  over a conventional bus. Among the other parts of the computer are input/output devices for handling network communications including first (public) and second (proprietary) controller area network (CAN) interfaces  250 . A vehicle electrical power system  245  provides power to all of the components. Microprocessor  272  is directly connected to input and output devices installed in the cab of a vehicle. 
         [0019]    CAN system  104  includes two distinct controller area networks based on a first bus using the public codes of the Society of Automotive Engineers (SAE) standard for J1939 networks and a second using proprietary codes, the definition of which is allowed under the standard. By “proprietary” it is meant only that standard format J1939 data block may be defined as desired by an OEM. The public bus connects first CAN interface  250  to a plurality of system controllers including an instrument and switch bank  212 , a gauge cluster  214 , an anti-lock brake system controller  219 , a transmission controller  216  and an engine controller  220 . Any of these controllers may in turn be connected to one or sensors of packages of sensors associated with a specific controller. For example, ABS controller  219  collects data from sensors  231  which include at least the wheel speed sensors used for determining skidding. Transmission controller  216  may track transmission fluid levels or include a drive shaft tachometer from drive train sensors  217 . The most important collection of sensors though is the engine sensor package  221  connected to the engine controller  230  which includes an engine tachometer, an air intake temperature gauge (providing a reasonable reading of ambient temperature), coolant temperatures, and engine oil temperature, level and dielectric constant readings. The engine controller  220  provides a convenient point of connection for a urea level sensor  270  which monitors urea tank  271  fill levels. 
         [0020]    Microprocessor/body computer  230  is itself a controller and can be used for direct monitoring of vehicle components, such as the working status of lights connected to an electrical system  233 . Body computer  230  operates as a controller on two distinct CAN busses. Devices using proprietary codes are coupled to the second bus and here include a GPS receiver unit  242 , a specialized controller  244  and a cell-phone transceiver unit  240 , each of which include a CAN interface  250 . Transceiver unit  240  additionally a microcontroller  241 , a modulating unit  243  and a transceiver unit  245  connected to an antenna  247 . Data collected by body computer  230 , mostly over the first CAN network, are transferred using code blocks defined for that function over the second CAN network to cell phone unit  240  where it is used to modulate a carrier for transmission. Body computer  230  has access to data such as mileage and to clock information, fuel consumption and urea tank fill levels, as well as GPS data, allowing the body computer to stamp data records as to time, date, mileage and location relating to sensor reading falling outside of normal reading categories or otherwise meeting some criteria defined by the operator. This is based on a need or desire to maintain the record for use of the central server  114 . 
         [0021]    Referring to  FIG. 3 , a flow chart is used for describing operations at the vehicle and server level supporting the system and process of the present invention. Upon start of a vehicle, and recurring periodically thereafter vehicle  102  location is obtained from a GPS unit  303  or equivalent (step  301 ). At step  305  the vehicle&#39;s destination list is updated. GPS location information may be used to key removal of destinations from the top of the list and follow on destinations may be reordered and added. With each update of the destination list projected routes are changed (step  307 ). A geographic information system  309  may be accessed to produce routes including considerations such as detours or even instant traffic conditions. It is conceivable on some vehicles that the routing and destination ordering may be made interactive, based on availability of routes and congestion considerations. The projection  311  of urea consumption may be based on projected fuel economy for the selected routes and a range estimated based on projected usage and the current urea tank fill level. Once this is done urea replenishment options may be generated for display to the driver (step  313 ) emphasizing urea service facilities  190  located along projected routes. If the options are not favorable, pre-staging of urea at a urea service facility  190  may be considered (step  315 ) and positioning (step  317 ) of supplies made. 
         [0022]    Those skilled in the art will now appreciate that alternative embodiments of the invention can exist. While the invention is shown in one of its forms, it is not thus limited but is susceptible to various changes and modifications without departing from the spirit and scope of the invention.