Abstract:
An apparatus for remote identification of the combustion performance of a vehicle is provided. The apparatus comprises a throttle device for control of fuel into an engine of a vehicle. A combustion sensor is in operative communication with the vehicle for the purpose of analyzing a vehicle combustion performance parameter. A remote communication device is in operative communication with the combustion sensor for communicating the combustion performance parameter. A remote monitoring network is included for receiving the combustion performance parameter from the remote communication device over a network to enable remote monitoring of vehicle performance.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    The present invention relates to an apparatus for remote communication of a combustion performance parameter of a vehicle. In particular, to the remote communication of information from one or more of a plurality of sensors of vehicle combustion, including for the purpose of identifying vehicles with imperfect performance, combustion problems, or other problems related to fuel economy.  
           [0002]    Internal combustion engines burn a mixture of fuel and air in a combustion chamber. The ignition of the air/fuel mixture creates the energy to drive the engine, but also creates a wide variety of exhaust gases. Also, even the most efficient internal combustion engines fail to burn all of the available air/fuel mixture. Thus, in addition to exhaust gases, some amount of unburned fuel comprises another unfortunate by-product of all internal combustion engines. Some portion of these by-products of combustion find their way into the engine causing premature deterioration of the engine, while the remainder of the by-products travel through the exhaust system of the vehicle, and eventually enter the atmosphere in one form or another. Compounding the problem is the fact that the natural consequence of driving a vehicle is the degeneration of the engine in terms of its ability to run efficiently, which accelerates the problem over time. Thus, even the most fuel-efficient vehicles fully equipped with pollution reduction devices generate excess pollution and eventually will become progressively more wasteful and inefficient over time. The effect on the environment of exhaust gases and the other by-products of internal combustion engines comprises one of the single greatest problems faced by today&#39;s society. The prior art offers a myriad of solutions to the problems created by the by-products of combustion, however, much room for improvement still exists.  
           [0003]    Some of the common pollutants that result from internal combustion of hydrocarbon fuels include carbon dioxide (CO 2 )—the necessary by-product of complete combustion and a prime contributor to global warming, exhaust gases like the toxin carbon monoxide (CO), and hydrocarbons (HC) that result from incomplete combustion of the air/fuel mixture. Furthermore, various unfavorable nitrogen oxides (NOx) result from the thermal fixation of nitrogen that takes place from the rapid cooling of burnt hydrocarbon fuel upon contact with the ambient atmosphere. The amount of these pollutants produced varies based on a number of factors including the type of engine involved, the age and condition of the engine, the combustion temperature, the air/fuel ratio, just to name a few. Many devices attempt to regulate and control these mechanical, environmental, and chemical processes for the purpose of reducing vehicle emissions.  
           [0004]    For example, U.S. Pat. No. 5,315,977 discloses a device that limits fuel to an internal combustion engine in order to reduce emissions. The device, sold under the trademark EconoCruise® made by Mirenco, Inc. of Radcliffe, Iowa, reacts in response to a plurality of sensors to manipulate the maximum open throttle position. The device is very successful in eliminating and/or reducing fuel emissions by preventing a host of inefficient and wasteful driving habits that can accelerate engine deterioration as well as increase engine exhaust, and the device is effective in limiting the flow of unburned fuel into the engine.  
           [0005]    Another such device is disclosed in U.S. Pat. No. 6,370,472, which builds on the technology disclosed in the aforementioned patent, by incorporating it into a method and apparatus for reducing vehicle emissions through the use of satellite technology. A vehicle use profile is created by driving a vehicle over a predetermined course and monitoring throttle positions at predetermined intervals. The use profile reflects the driving habits of an efficient driver and can then be reproduced on subsequent trips over the same course by automatic means.  
           [0006]    While these inventions are highly effective in reducing vehicle emissions it may be helpful in many cases to identify on a preemptive basis vehicles that due to mechanical or other problems that are generating a higher than normal amount of vehicle exhaust. In particular, engine problems that can produce inefficient use of fuel and unwanted vehicle emissions cannot be detected by visually monitoring vehicle emissions at least until the problems have reached very serious proportions. Thus, a more robust detection scheme is desirable. Similarly, routine preventative maintenance can identify for repair inefficient vehicles. Such a program, however, cannot detect problems that occur between maintenance intervals and result in performing maintenance on vehicles without problems. While preventative maintenance is certainly beneficial, the process is not designed to identify on a realtime basis problem vehicles.  
           [0007]    In addition, maintenance and vehicle inspection programs cannot monitor on a realtime basis wasteful habits of inefficient drivers. It is know that individual driver performance can vary dramatically and have a substantial impact on fuel economy and therefore on vehicle emissions.  
           [0008]    Thus, a need exists for a method and apparatus for the realtime communication of parameter of combustion performance.  
         SUMMARY OF THE INVENTION  
         [0009]    An object of the present invention comprises providing a method and apparatus for an apparatus for remote communication of a combustion performance parameter of a vehicle.  
           [0010]    These and other objects of the present invention will become apparent to those skilled in the art upon reference to the following specification, drawings, and claims.  
           [0011]    The present invention intends to overcome the difficulties encountered heretofore. To that end, an apparatus for remote identification of the combustion performance of a vehicle is provided. The apparatus comprises a throttle device for control of fuel into an engine of a vehicle. A combustion sensor is in operative communication with the vehicle for the purpose of analyzing a vehicle combustion performance parameter. A remote communication device is in operative communication with the combustion sensor for communicating the combustion performance parameter. A remote monitoring network is included for receiving the combustion performance parameter from the remote communication device over a network to enable remote monitoring of vehicle performance. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]    [0012]FIG. 1 is a schematic drawing of the present invention for control of an engine, and monitoring a combustion parameter.  
         [0013]    [0013]FIG. 2 is a combination schematic and plan view of an alternative embodiment of the present invention for monitoring a combustion parameter and control of an engine without an electronic throttle.  
         [0014]    [0014]FIG. 3 is a breadboard diagram of a portion of the engine control apparatus of the present invention.  
         [0015]    [0015]FIG. 4 is a diagram of a catalytic converter with a plurality of combustion sensors. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0016]    In the Figures, FIG. 1 shows a schematic diagram of the present invention. In modern vehicles, an electronic engine computer  38  controls important engine functions including throttle control. Typically, the engine computer  38  sends and receives a throttle voltage control signal to and from a throttle pedal  42  in the form of a 5 v DC signal. The throttle voltage signal varies in proportion to the desired change in vehicle speed. In the case of car controlled manually by the driver, the engine computer  38  receives a throttle voltage control signal along a direct path between the engine computer  38  and the throttle pedal  42 . The engine computer  38  can then translate the throttle voltage into the appropriate signal to the fuel injectors  40  to ensure an engine response in proportion to the throttle voltage.  
         [0017]    In most modern vehicles, the engine computer  38  can take control of the throttle through a cruise control device  39 . In this case, the engine computer  38  would take control of the throttle voltage via a throttle voltage control signal path between the engine computer  38  and the throttle pedal  42 . This creates a feedback loop that allows the engine computer  38  to adjust the throttle voltage at the pedal  42  to control the vehicle to a certain speed.  
         [0018]    In part, the present invention builds on the cruise control model in the following manner. The invention includes a general-purpose computer  10  that uses a software control program to take control of the throttle voltage and control of a vehicle in accord with a pre-selected response from a plurality of external sensors. Those of ordinary skill in the art will appreciate that the computer  10  could consist of a lap top computer, a dedicated embedded controller device like the EconoCruise device, or any other similar computer. In particular, the computer  10  is connected to a Global Positioning Satellite receiver  12  (“GPS”) that receives absolute position information from an array of satellites  14 . The computer  10  is also connected to an exhaust emission analyzer  16  that is in operable communication with the exhaust manifold  18  of a vehicle. In the preferred embodiment of the present invention the exhaust analyzer  16  consists of a Model 6600 miniature automotive analyzer commercial available from Andros Incorporated of Berkeley, Calif. However, those of ordinary skill in the art will understand that any similar suitable analyzer could be used. In addition, the computer  10  interfaces with the engine computer  38  and the throttle pedal  42  in a manner that allows the computer  10  to control the throttle pedal  42  in the manner of a cruise control device.  
         [0019]    The invention employs a simple relay switch  26 , which switches between a factory throttle control position and a position whereby the computer  10  controls the throttle. In particular, the relay switch  26  employs a relay coil  28  that triggers the relay switch  26 . FIG. 1 shows the relay switch  26  set to the factory throttle control position  34 . In position  34 , the engine computer  38  assumes standard control over the throttle pedal  42 . In position  34  the engine computer  38  controls the throttle pedal  42  along the throttle voltage control signal path  44 . The throttle pedal communicates with the engine computer  38  along the throttle voltage control signal path  46 ,  48 . In the factory throttle control position  34 , throttle voltage control signal path  36  allows the computer  10  to monitor and record the throttle voltage signal.  
         [0020]    With the relay switch  26  set to a throttle voltage control position  30  the computer  10  assumes control over the throttle pedal  42 , and control over the throttle signal sent to the engine computer  38 . In position  30 , the throttle signal travels from the throttle pedal  42  along the throttle voltage control path  46 ,  36  to the computer  10 . The computer  10  can then send the throttle voltage signal back to the engine computer  38  and to the throttle pedal  42  along throttle voltage control path  32 ,  48 ,  44 . The invention includes a common ground path  52  linking the computer  10 , engine computer  38 , and throttle pedal  42 . Two manually activated switches actually trigger the relay switch  26 . A brake switch  20  is connected through a DC power supply  22  to the relay switch  26 , to allow the driver to manually set the relay switch  26  to the factory control position  34  by tapping the brake pedal. A steering wheel switch  24  allows the driver to manually set the relay switch  26  in either the factory control position  34  or the computer control position  20 .  
         [0021]    [0021]FIG. 2 shows an alternative embodiment of the present invention for use with vehicles without engine computers, or electronic voltage control capacity. In this embodiment, a throttle apparatus  114  is mounted atop a governor control box  116 . The governor control box  116  includes a top plate  134  on which is mounted a speed control lever  130 . The speed control lever  130  pivots about the pivotal mount  132  that extends down through the top plate  134 . The speed control lever  130  is controlled in response to a throttle cable (not shown) that extends from the throttle pedal or foot-operated accelerator pedal (not shown) to a throttle cable hook  115 . The throttle cable hooks to the speed control lever  130 , and moves the speed control lever  130  in response to changes in the throttle pedal as controlled by the driver&#39;s foot. Movement of the speed control lever  130  serves to control the flow of fuel into the engine, thereby controlling the vehicle speed. Also mounted to the top plate  134  is a stop lever  136 . The stop lever  136  is mounted for pivotal movement on a vertical shaft that extends through the top plate  134 . The stop lever  134  is biased toward an ideal position. Placing a physical stop in the path of the stop lever  134  serves to limit the maximum movement of the speed control lever  130 , and thereby limits the maximum rate that fuel enters the engine. The exact operational details of the interaction between the governor control box  116  and its related engine components are disclosed in more detail in U.S. Pat. No. 5,315,977.  
         [0022]    In the present invention, a linear actuator  120  (or alternatively a stepper motor), controlled by the computer  10 , is mounted to the top plate  134  of the governor control box  116 . The linear actuator  120  is interfaced with the computer  10  by the common ground line  64 , and along the throttle control signal path  48 ,  36 . The linear actuator  120  is linked to DC power supply  22  along signal path  62 . The linear actuator  120  has a screw  122  that is extendable and retractable in fine, exact, and reproducible increments. An end  124  of the screw  122  serves as a mechanical stop for the stop lever  136 . The linear actuator  120  interfaced to the computer  10  provides a means to control the throttle of engines that do not include an electronic throttle voltage signal.  
         [0023]    A potentiometer  128  is mounted to the top plate  134 . The potentiometer  128  includes cylinder  126  that mounts to the speed control lever  130 . The cylinder  126  extends and retracts in response to movement of the speed control lever  130 . The position of the cylinder  126  is translated to a voltage signal by the potentiometer  128 , wherein the signal correlates to the throttle position. The voltage signal is interfaced with the computer  10  in the following manner. The potentiometer  128  has a common ground  52 , and is powered by DC power supply  54 . The DC power supply  54  is linked to the computer  10  and sends power to the potentiometer  128  along signal path  56 . An output signal is sent from the potentiometer  128  to the computer along signal path  46 ,  36 . The output signal consists of the throttle position as measured and converted to an electronic voltage signal by the potentiometer  128 . In this manner, the potentiometer  128  allows the computer to monitor an electronic throttle voltage signal.  
         [0024]    The computer  10 , linked to the potentiometer  128  and linear actuator  120 , controls the operation of the engine in the manner described above in reference to engines with electronic throttle control. In the embodiment of the invention shown in FIG. 2, when the relay switch  26  is in the factory control position  34 , the linear actuator  120  is programmed to withdraw the screw  122  to its retracted position such that the stop lever  136  and the speed control lever  130  operate without interference. In the factory control position  34 , the computer  10  can still monitor the throttle voltage via the signal path  46 ,  36  extending from the potentiometer  128  to the computer  10 . With the relay switch  26  in the throttle voltage control position  30 , the computer  10  receives the converted throttle voltage signal from the potentiometer  128  along the signal path  46 ,  36  and can control the throttle by sending signals to the linear actuator  120  along the signal path  34 ,  48 . Thus, the computer  10  can execute engine control in the same manner described hereinabove in reference to the embodiment shown in FIG. 1. Of course, those of ordinary skill in the art will understand that, without departing from the scope of the intended invention, the specific configuration required for controlling vehicles without electronic throttles and/or electronic engine computer will vary depending on the make and model of the vehicle involved.  
         [0025]    In the various manners described hereinabove, the computer  10  can directly assume control of the throttle voltage in response to one or more of the sensors. Specifically, the computer  10  can take control of the throttle voltage and manage the voltage in response to at least three sensor inputs. First, the computer can manage the throttle position in the same manner as a conventional cruise control. That is the system can adjust the throttle voltage based on driving conditions to maintain as close as possible a constant speed. Secondly, the computer  10  can control the throttle voltage in response to input from the emission analyzer  16 . In this mode, the computer may monitor the emission analyzer to ensure that the emissions stay below a certain level. For example, through experimentation it may be desired to keep emission levels below a certain opacity threshold (where 0% would be completely clear exhaust and 100% would be completely opaque exhaust), or below some other predetermined level of a particular exhaust gas. If the threshold level is exceeded the computer can reduce the throttle voltage or institute some change in the fuel makeup or mixture until the emission level drops below the threshold.  
         [0026]    Third, the computer  10  could control the throttle voltage in response to information from the GPS receiver  12 . This control mode would likely involve the establishment of a throttle voltage profile. This can be accomplished by allowing a driver of particularly high skill in driving to conserve fuel to drive the vehicle over a predetermined course. The relay switch  26  would be set to the factory control position  34 , enabling the computer  10  to collect throttle voltage information, and time, position, and elevation data from the GPS receiver  12  in communication with the satellites  14 . Furthermore, vehicle speed could also be monitored by the computer  10  or computed based on the time and position data. This information could be collected on a periodic basis, for example, once a second or once every 100 feet, or any other convenient interval. This information can be recorded and used at a later date on a trip by another driver over the same or substantially similar route, in the same or substantially similar vehicle. On the return trip the computer  10  can use the previously created profile to control the throttle position. Again, with the GPS sensor  12  activated, the computer  10  can compare the current vehicle position and throttle voltage to the historical data, and use adaptive techniques to match the current throttle voltage to the throttle voltage at the same location based on the historical data.  
         [0027]    In addition to the sensors mentioned hereinabove, other sensors could be used with the present invention. For example, a wind resistance sensor could be used to calculate wind speed and direction. This information would be used by the computer  10  to adjust the throttle voltage. The computer  10  would be able to calculate adjustments to throttle voltage to compensate or adjust for any differences between current wind resistance and the wind resistance at the time the historical data was collected.  
         [0028]    In practice, the best results, i.e. those results that minimize emissions and maximize fuel economy, may-be achieved by a control program that combines all responses to all three sensors to achieve the most efficient performance. In general, the control program would follow the control flow represented by the following pseudo code:  
                                   BEGIN CONTROL LOOP [While Brake_Pedal = On]       {         OBSERVE Pollution         CALCULATE c= Fuel(Pollution)         CALCULATE b = Prediction(x)         CALCULATE a = Throttle(x)         CALCULATE Throttle_Power_New = a + b + c + Throttle —           Power_Old         Apply Throttle_Power_New         CALCULATE Throttle_Power_Old = Throttle_Power_New       }       REPEAT LOOP                  
 
         [0029]    Pollution is the response from the emission analyzer  16 . The value of x equals the vehicles real world position, speed, and/or elevation as determined by the GPS receiver  12 . The Fuel function uses the parameter Pollution to calculate the throttle voltage adjustment coefficient c that becomes a component of the throttle adjustment equation. If the emission threshold is within the predetermined tolerance then the value of c equals zero. If the emission threshold is exceeded then the value of c would become negative, exerting a drag on throttle voltage. This would then begin to slow the vehicle until the emission level drops below the threshold level. Alternatively, if the emission threshold is exceeded the fuel mixture or composition could be altered by the computer  10  to reduce the emissions. In particular, the air/fuel mixture could be adjusted, or water and/or a mixture of water and alcohol could be added to the fuel mixture to reduce emissions. Water and/or a water and alcohol mixture could be either port injected or injected directly into the combustion chamber to reduce, for example, oxides of nitrogen (NOx).  
         [0030]    The Prediction function uses the parameter x to calculate the throttle voltage adjustment coefficient b. The Prediction equation could be as simple as exactly matching the historical throttle voltage to the current voltage. In practice, however, driving and vehicle conditions vary enough that this method may not produce the best results. An alternative Prediction function would match the slope of the historical run to the current run. In other words, the function would look ahead a specified number of control points (based on either time or distance) and determine the slope of the historical throttle voltage versus time/distance curve, and then apply that slope to the current data to adjust current throttle position. The coefficient b could be negative or positive depending on whether the throttle voltage needs to be decreased or increased, respectively.  
         [0031]    The Throttle function uses the parameter x to calculate the throttle voltage adjustment coefficient a. The Throttle function comprises the direct attempt to control speed, and would use the standard cruise control equations known in the art to perform this function. These equations attempt to drive the difference in actual speed and a target speed (delta speed) to zero. In situations where either coefficient b or c become large enough that an imbalance exists between the values of b or c, and a, then an adjustment to the target speed will be needed. This will result, for example, when the historical profile shows that the vehicle is approaching a major uphill or downhill section of the road. In the case of a downhill section, the Prediction function will allow the vehicle to gain speed down the hill, while at the same time the Throttle function will attempt to slow the vehicle. If this imbalance will persist over more than a couple of control points, the target speed would be raised to correct the imbalance. In the situation where the vehicle is approaching a major uphill section requires the reverse control method.  
         [0032]    The values of the coefficients a, b, c can be determined by the computer  10  based on a predetermined weighting scheme that seeks to achieve the best overall performance, or the driver can set or influence the values on a real time basis. For example, the driver could enter information into the computer  10  instructing the computer  10  to control the throttle voltage to maximize or minimize fuel economy, emissions, or to maintain a constant speed. The relative importance the driver gives to these factors would determine the weight given to each of the coefficients a, b, c.  
         [0033]    Another feature of the present invention is the ability of the computer  10  to predict and report the difference in fuel economy or the amount of emission reduction achieved under throttle control. The computer  10  can track the changes, corrections, or adjustments made to the throttle voltage in relation to straight cruise control, for example, and keep a log of the improvement to fuel economy or emission reduction that results. This information would be useful in quantifying the value of the invention in terms of fuel savings, or emission reduction.  
         [0034]    Those of ordinary skill in the art will understand that the exact control method and equations will vary depending on the vehicle, the vehicle load, the road, and driving conditions. Thus, some experimentation and profiling will be required in order to determine the exact equations and weighting factors.  
         [0035]    Another aspect of the present invention includes a remote communication device (RCD)  17  operatively connected to the computer  10 , or alternatively directly connected to the exhaust analyzer  16  (connection shown in phantom). The RCD  17  provides for transmission of information received from one or more of a plurality of sensors that monitor some indicator of engine performance and/or of engine combustion. For example, the RCD  17  could transmit information from the exhaust analyzer  16  to a remote monitoring location  21  via a communication network  19 . The remote communication scheme for communicating combustion performance parameter like exhaust analyzer information could utilize a wireless modem device and communication network, a cellular network, a PCMCIA communication device, a radio transmitter and transceiver, satellite communications technology, or the like.  
         [0036]    The information transmitted from the exhaust analyzer  16  could include important parameters of engine performance and fuel combustion like HC, CO, CO 2 , O 2 , and NOx gas concentrations. From these parameters a person or device at the remote monitoring location  21  could quickly identify on a realtime basis poor performing vehicles, or changes in vehicle performance that should be addressed through maintenance procedures or modification of driving behavior. For example, the remote monitoring location  21  could utilize a computer program means to identify out of range conditions for certain exhaust parameters, or a manual system could be used where a person monitors the information coming from the exhaust analyzer  16  at predetermined intervals. In either event, any particular problem vehicle could be quickly identified based on indicators of engine performance, or driver behavior that would lead to poor fuel economy, allowing for immediate remedial attention.  
         [0037]    In addition, the RCD  17  could transmit information from a catalytic converter  100  configured with plurality of sensors (FIG. 4). The sensors associated with the catalytic converter  100  can interface with the computer  10 , or directly with the RCD  17 . The catalytic converter  100  comprises a secondary combustion chamber that combusts unburned fuel expelled from the engine. The amount of combustion that takes place in the catalytic converter  100  indicates the quality of the primary combustion process. However, while reducing emissions of unburned fuel and its constituent components, the catalytic converter can hide inefficiencies in engine performance thereby making it difficult to identify problem conditions that need correction or that would over time lead to serious engine deterioration. Thus, it is desirable to monitor engine combustion performance in a manner tat accounts for the activity of the catalytic converter  100 . Communication of the output one or more of the plurality of sensors associated with the catalytic converter  100  to the RCD  17 , or to the computer  10 , would allow detection of any such problem in combustion performance. Monitoring the catalyst bed temperature, inlet/outlet temperature, and the inlet/outlet CO 2  or O 2  levels or some combination of the foregoing sensors would allow for determining the amount of secondary combustion taking place in the catalytic converter  100  and by proxy the performance of the primary combustion taking place in the engine of the vehicle. In particular, the monitoring could be based on the differential between inlet/outlet temperatures, based on catalyst bed temperature, or based on the differential between inlet/outlet CO 2  or O 2  levels.  
         [0038]    Another sensor capable of adaptation for use with the present invention comprises an accelerometer  102 . An electromechanical or mechanical accelerometer  102  can be attached to the engine to detect irregularities in engine combustion performance through detection of very small irregularities in acceleration. For example, an accelerometer  102  could detect irregular cylinder firing patterns, or even a dead cylinder, that might not be detectable to the operator of the vehicle. The accelerometer  102  can interface directly with the computer  10 , or to the RCD  17 , for communication to the remote monitoring location  21 .  
         [0039]    An opacity sensor is yet another example of a sensor capable of adaptation for use with the present invention for communication of parameters of engine combustion performance (see FIG. 4). The opacity sensor could interface with the computer  10 , or directly with the RCD  17 , for communication to the remote monitoring location  21 . The opacity sensor essentially would measure the amount of particulate in the engine exhaust, which is a measure of combustion quality. The more particulate in the exhaust the less efficient the combustion process, and the more likely that the engine has developed or will develop, problems that require mechanical attention. In practice, it would be advisable to use periodic sampling and retract or cover the opacity sensor when not in use to limit its exposure to engine exhaust. Prolonged exposure could coat the sensor with carbon thereby limiting its utility.  
         [0040]    The following information is helpful in illustrating the utility of realtime monitoring of some measure combustion efficiency. Table 1 shows the partial results of opacity testing performed on the exhaust of a fleet of school buses with very new engines (three of the mileage entries are believed to be excessive and the result of data entry error). The data shows that even with relatively new engines at least three of the buses exhibited opacity readings in excess of 18%, and one bus had a reading of 27.5%. The fleet averaged an opacity reading of 7.78%. Thus, the information in Table 1 clearly identifies three candidate vehicles for inspection and/or maintenance based on poor combustion performance. Without this testing information the problems in these vehicles would likely have gone undetected due to the fact that the opacity levels were not high enough to allow for visible detection, and new vehicles would likely not be scheduled for the type of maintenance that would detect the underlying problems. Left undetected the problem would worsen possibly to the point of requiring engine replacement, and at the least the vehicle would waste fuel and needlessly increase pollutants until the problem is detected or corrected. Accordingly, the realtime availability of such data would be very useful in identifying problem vehicles and facilitating changes thereto.  
                                                                                           TABLE 1                           2002 School Bus Opacity Data                                            Current                                       PM       Number                               Density %       of   Vehicle       Engine   Engine   Injection   Hours/       before       vehicles   Number #   Location   Manufacturer   Model   Type   Mileage   Year   DriverMax                    2542   6   Clear Lake   Navistar/IH   V8   Electronic   18,868   2002   27.50       2543   02-14   Van Horne   Navistar/IH   V8   Electronic   17,373   2002   18.70       2544   6   Elk Horn - Kimballton   Navistar/IH   V8   Electronic   8,472   2002   18.00       2545   03   Prescott   Navistar/IH   V8   Electronic   8,741   2002   13.10       2546   33   Iowa City   Navistar/IH   V8   Electronic   713   2002   13.00       2547   2   Burnside   Navistar/IH   V8   Electronic   14,464   2002   11.70       2548   3   Rock Valley Christian   Navistar/IH   V8   Electronic   8,342   2002   11.60       2549   8   Buffalo Center   Navistar/IH   V8   Electronic   13,395   2002   11.20       2550   8   Clear Lake   Navistar/IH   V8   Electronic   10,499   2002   10.40       2551   12   Carroll   Navistar/IH   V8   Electronic   6,179   2002   10.30       2552   32   Iowa City   Navistar/IH   V8   Electronic   723   2002   9.93       2553   16   Nevada   Navistar/IH   V8   Electronic   8,503   2002   9.73       2554   4   Lenox   Navistar/IH   V8   Electronic   16,378   2002   8.80       2555   29   Iowa City   Navistar/IH   V8   Electronic   79   2002   8.75       2556   31   Iowa City   Navistar/IH   V8   Electronic   71   2002   8.28       2557   9   South Page   Navistar/IH   6 cyl   Electronic   3,060   2002   8.16       2558   01   Farragut   Navistar/IH   V8   Electronic   8,884   2002   7.84       2559   30   Iowa City   Navistar/IH   V8   Electronic   73   2002   7.33       2560   202   Spencer   Navistar/IH   6 cyl   Electronic   7,823   2002   6.98       2561   4   Iowa City   Navistar/IH   V8   Electronic   73   2002   6.83       2562   01-6    Sioux Central   Navistar/IH   V8   Electronic   15,262   2002   6.76       2563   22   New Hampton   Navistar/IH   V8   Electronic   217   2002   6.62       2564   9   South O&#39;Brien   Navistar/IH   V8   Electronic   12,898   2002   6.50       2565   14   Fremont- Mills   Navistar/IH   V8   Electronic   7,552   2002   6.28       2566   01   Hull-Western Christian   Navistar/IH   V8   Electronic   17,845   2002   6.22               High       2567   7   Clear Lake   Navistar/IH   V8   Electronic   14,378   2002   6.04       2568   3   Perry   Navistar/IH   6 cyl   Electronic   1,892   2002   6.01       2569   28   Ankeny   Navistar/IH   V8   Electronic   8,057   2002   5.63       2570   9   Grundy Center   Navistar/IH   V8   Electronic   15,080   2002   5.57       2571   2   Clarksville   Navistar/IH   V8   Electronic   447   2002   4.83       2572   22   Allamakee-Waukon   Navistar/IH   6 cyl   Electronic   353   2002   4.39       2573   2   Wyoming   Navistar/IH   V8   Electronic   9,293   2002   4.00       2574   2   Odebolt   Navistar/IH   V8   Electronic   2,997   2002   3.91       2575   10   Valley, Elgin   Navistar/IH   IH   Electronic   3,168   2002   3.25                       T444E       2576   21   Spirit Lake   Navistar/IH   6 cyl   Electronic   3,728   2002   2.99       2577   05   Decorah   Navistar/IH   6 cyl   Electronic   9,310   2002   2.98       2578   2   Alta   Navistar/IH   V8   Electronic   5,319   2002   2.64       2579   55   Lynnville Sully   Navistar/IH   6 cyl   Electronic   1,535   2002   2.60       2580   11   Wellman-Mid Prairie   Navistar/IH   6 cyl   Electronic   1,656   2002   1.96       2581   27   Decorah   Navistar/IH   6 cyl   Electronic   11,821   2002   1.23       2582   12   Wellman-Mid Prairie   Navistar/IH   6 cyl   Electronic   2,507   2002   0.34                                   Average   7.78                  
 
         [0041]    As Table 1 indicates the problem of poor combustion is not isolated to older vehicles, even new engines can have substantial engine performance or fuel combustion problems. For example, vehicle number 6 with 8472 miles had an opacity level of 18%, while vehicle number 05 with 9,310 miles had an opacity level of 2.98%. Clearly, there is a problem with the vehicle number 6 that likely existed from the day the bus arrived from the factory. Without this information it is unlikely that a brand new bus would have been tested, or thought to have such a problem, and the problem would have persisted causing further engine damage, continued to waste fuel, thereby needlessly increasing the cost of operation as well as pollution levels. However, as expected older vehicles show even worse deterioration.  
         [0042]    Table 2 shows partial data taken from a fleet of older school buses with 1987 engines. The data shows that seven of the buses have opacity readings of 55% or more, indicating major engine or combustion problems. Also, a large number of the buses have opacity readings in excess of 28% also indicating some level of deterioration and poor performance. All of these buses would be candidates for some level of maintenance, ranging from a tune up to engine replacement. Again, this illustrates the benefit from realtime monitoring and profiling of vehicle performance and of the performance of a fleet of vehicles, without which the problems would have persisted.  
         [0043]    Such analysis done realtime eliminates the need to take the vehicle out of service for special testing, and allows for more closely monitoring the performance to better detect changes in performance. In addition, it is anticipated that the realtime monitoring could not only detect engine performance and combustion problems, but also detect difference in driving habits of drivers of fleet vehicles. If the data suggests that engine performance or combustion performance for some drivers is better than others, remedial action can be taken to transfer the techniques of the more skilled drivers to the less skilled drivers also resulting in better vehicle performance, reduced need or maintenance, and in reduced fuel costs.  
                                                                                                                                       TABLE 2                           1987 School Bus Opacity Data                Opacity                            Current                       PM       Number   Fleet Analysis       Density %   Soot            of   Vehicle       Engine   Engine   Injection   Hours/       before   # Soot       vehicles   Number #   Location   Manufacturer   Model   Type   Mileage   Year   DriverMax   Before                    4399   8701   Cedar Rapids   Navistar/IH       Mechanical   161,710   1987   75.10   432.13       4400   1   Pella   Navistar/IH   6 cyl   Mechanical   19,271   1987   59.80   344.09       4401   30   Huffman Trans. Mason City   Navistar/IH   V8   Mechanical   140,836   1987   59.00   339.49       4402   15   lowa Falls   Navistar/IH   6 cyl   Mechanical   159,149   1987   58.90   338.92       4403   8705   Cedar Rapids   Navistar/IH       Mechanical   155,875   1987   58.10   334.31       4404   11   AR-WE-VA   Navistar/IH   6 cyl   Mechanical   141,589   1987   56.70   326.26       4405   10   Keokuk   Navistar/IH   6 cyl   Mechanical   124,745   1987   55.00   316.48       4406   5   East Greene   Navistar/IH   6 cyl   Mechanical   165,830   1987   52.00   299.21       4407   15   Mt. Pleasant   Navistar/IH   IHT444E   Mechanical   161,568   1987   48.00   276.20       4408   7   Mediapolis   Navistar/IH   V8   Mechanical   223,621   1987   43.40   249.73       4409   28   Huffman Trans. Mason City   Navistar/IH   V8   Mechanical   123,096   1987   42.90   246.85       4410   87   Moville   Navistar/IH   6 cyl   Mechanical   147,653   1987   42.70   245.70       4411   24   Eddyville   Navistar/IH   6 cyl   Mechanical   222,782   1987   41.90   241.10       4412   707   Western Dubuque   Navistar/IH   V8   Mechanical   147,175   1987   41.30   237.64       4413   7   Hull-Western Christian High   Navistar/IH   6 cyl   Mechanical   217,288   1987   41.00   235.92       4414   704   Western Dubuque   Navistar/IH   V8   Mechanical   217,153   1987   39.90   229.59       4415   702   Western Dubuque   Navistar/IH   V8   Mechanical   142,567   1987   39.60   227.86       4416   14   Sioux City   Navistar/IH   6 cyl   Mechanical   180,417   1987   38.70   222.68       4417   39   Fort Madison   Navistar/IH   6 cyl   Mechanical   51,266   1987   38.16   219.23       4418   8707   Cedar Rapids   Navistar/IH       Mechanical   173,121   1987   38.00   218.66       4419   9   Miles   Navistar/IH   6 cyl   Mechanical   157,083   1987   36.90   212.33       1420   10   Miles   Navistar/IH   V8   Mechanical   147,628   1987   36.80   211.75       4421   2   Pella Christian   Navistar/IH   V8   Mechanical   154,075   1987   35.00   201.39       4422   8702   Cedar Rapids   Navistar/IH       Mechanical   186,182   1987   35.00   201.39       4423   18   Wapello   Navistar/IH       Mechanical   132,431   1987   34.30   197.37       4424   8704   Cedar Rapids   Navistar/IH       Mechanical   178,810   1987   34.00   195.64       4425   8703   Cedar Rapids   Navistar/IH       Mechanical   166,606   1987   33.80   194.49       4426   9   Burnside   Navistar/IH   6 cyl   Mechanical   145,135   1987   33.70   193.91       4427   703   Western Dubuque   Navistar/IH   V8   Mechanical   158,238   1987   32.90   189.31       4428   8   Nora Springs   Navistar/IH   6 cyl   Mechanical   170,526   1987   32.50   187.01       4429   8714   Cedar Rapids   Navistar/IH       Mechanical   179,176   1987   30.80   177.23       4430   5   Nashua   Navistar/IH   V8   Mechanical   151,377   1987   30.70   176.65       4431   87   Boyden-Hull   Navistar/IH   V8   Mechanical   67,782   1987   30.00   172.62       4432   15   Sioux City   Navistar/IH   6 cyl   Mechanical   179,968   1987   29.60   170.32       4433   7   Monticello   Navistar/IH   V8   Mechanical   180,542   1987   28.70   165.14       4434   14   Fort Madison   Navistar/IH   DT360   Mechanical   198,896   1987   28.70   165.14                  
 
         [0044]    The foregoing description and drawings comprise illustrative embodiments of the present inventions. The foregoing embodiments and the methods described herein may vary based on the ability, experience, and preference of those skilled in the art. Merely listing the steps of the method in a certain order does not constitute any limitation on the order of the steps of the method. The foregoing description and drawings merely explain and illustrate the invention, and the invention is not limited thereto, except insofar as the claims are so limited. Those skilled in the art that have the disclosure before them will be able to make modifications and variations therein without departing from the scope of the invention.