Patent Publication Number: US-2012041637-A1

Title: Engine diagnostic system and method for capturing diagnostic data in real-time

Description:
BACKGROUND 
     Sophisticated electronic control systems have been used in the heavy-duty vehicle industry to control various vehicle operations. In addition, heavy-duty vehicles are also provided with onboard electronic engine diagnostic (“OBEED”) systems that assist technicians in diagnosing problems that occur during operation of the vehicle. More specifically, when an electronically controlled engine system is found to be operating out of specification, the diagnostic OBEED system stores a fault code in an onboard computer. A warning light, such as a check engine light (“CEL”) or a stop engine light (“SEL”), is triggered to illuminate, indicating that a fault has occurred. 
     Traditionally, to determine the root cause of a fault codes, the stored fault codes must be accessed by a repair specialist. To accomplish this task, the vehicle must be brought to a repair facility where a diagnostic reader/computer is hard-wired to the OBEED system to download the previously recorded OBEED fault codes stored in the onboard computer. A technician correlates the OBEED fault code with a lookup table (either a manual or electronic lookup table) and determines which engine components may be associated with the fault code. 
     However, while the stored fault codes in the OBEED system indicates which engine component may have triggered the fault code, in some instances, technicians also need to review a “snapshot” or a “flight recording” of the engine operating systems contemporaneously with the fault code, to determine the root cause of the fault code. Currently, to obtain the snapshot or flight recording, the repair facility must put two technicians in the vehicle; one person driving the vehicle and another with a computer hardwired to the vehicle operating system and try to replicate the fault code occurrence, as well as capture and/or record the data related to the fault code occurrence event, in real time. This process can take anywhere from several hours to several days to replicate the code occurrence. Unfortunately, the vehicle is rendered idle during this process, in addition to any subsequent required repair time or wait time for necessary parts to arrive at the repair facility. Indeed, each day that the vehicle is idle translates to approximately $800-$1200 per day of revenue for its driver. 
     Accordingly, what is needed is a diagnostic tool that reduces diagnostic testing procedures and captures data regarding engine operating systems that is associated with diagnostic fault codes, in real time to reduce, if not eliminate, diagnostic testing. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Features and advantages of the disclosure will be apparent from the following detailed description and the appended claims, taken in conjunction with the accompanying drawings, in which: 
         FIG. 1  schematically illustrates an exemplary data communication scheme for a heavy duty vehicle; and 
         FIG. 2  is a flow chart illustrating operation of the data communication scheme illustrated in  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
     Referring now to the discussion that follows and to the drawings, illustrative approaches to the disclosed systems and methods are described and shown in detail. Although the drawings represent some possible approaches, the drawings are not necessarily to scale and certain features may be exaggerated, removed, or partially sectioned to better illustrate and explain the disclosed device. Further, the descriptions set forth herein are not intended to be exhaustive or otherwise limit or restrict the claims to the precise forms and configurations shown in the drawings and disclosed in the following detailed description. 
       FIG. 1  schematically illustrates an exemplary data communication scheme  10  for use with a vehicle  12 , such as a heavy duty vehicle that includes a tractor  14  and trailer  16 . As will be explained in further detail below, vehicle  12  is wirelessly linked with a fleet management center server  18  using data communication scheme  10 . 
     Vehicle  12  includes various electronic subsystems that independently control and/or monitor individual vehicle operations. The electronic subsystems are operatively connected together, via an engine control module  20 . Engine control module  20  is configured to communicate with the various electronic subsystems, as well as controlling and monitoring the operational parameters of a vehicle engine and drive train, including, but not limited to at least the engine transmission and differential. Exemplary operational parameters include, but are not limited to, engine operating temperatures and pressures, as well as component commands, such as open, close, modulate or respond. 
     In an exemplary arrangement, as part of data communication scheme  10 , engine control module  20  utilizes a data link  22  to transmit various status and/or control messages from engine control module  20 . For example, data link  22  may be configured to transmit engine speed, oil temperature, accelerator pedal position, vehicle speed, and the like. In one exemplary arrangement, data link  22  conforms to SAE J1939 and SAE J1587 to provide various service, diagnostic, and control information to other engine systems, subsystems, and connected devices, as will be explained below in further detail. 
     In one aspect of the disclosure, data link  22  is used as part of an onboard electronic engine diagnostic (“OBEED”) system that is operatively connected to engine control module  20  to transmit event fault codes when engine control module  20  determines that an engine system is found to be operating out of a predefined specification. Traditionally, data link  22  has been hardwired to a diagnostic tool or an external computer to electronically transmit fault codes for the purpose of performing diagnostic testing to ascertain root causes of the event fault code. However, while fault codes are electronically stored in the engine control module  24 , the engine operating parameters and/or the component commands at the time of event fault code are not traditionally captured. 
     In accordance with one aspect of the present disclosure, to reduce diagnostic testing required to replicate an event fault code and capture engine operating parameters and/or component commands during the event fault code occurrence, data link  22  of the present disclosure is configured to transmit engine operating parameters and component command information, at least during an event code occurrence. In one exemplary arrangement, data communication scheme  10  includes data link  22  being configured to wirelessly transmit engine operating parameters and component commands across a network  23  to a log file  24  in a remote fleet management center server  18 . In one exemplary arrangement, the wireless transmission across network  23  may be performed either via a satellite  26  or a cellular tower  28  to server  18 . Server  18  may be configured to transmit log file  24  to a pre-selected repair facility  30  upon a determination of an event code occurrence. 
     In accordance with a further aspect of the disclosure, to insure that engine operating parameter and/or component command data is available for a predetermined time before an event fault code has occurred, as well as just after an event fault code has occurred, data link  22  is also configured to perform a continuous capture of engine operational information to a ring buffer  32  within log file  24  disposed in remote server  18 . More specifically, in the context of the present disclosure, continuous capture refers to the capture of a specific predetermined time duration of the engine operational information that when reached, automatically deletes the oldest information from log file  24  to make room for the newest information. In other words, data link  22  transmits a “snapshot” or “flight recording” of the engine operational information for a predetermined time period. 
     In addition to continuously capturing engine operating parameters and component commands to ring buffer  32 , data communication scheme  10  also provides for engine control module  20  and data link  22  to be configured to wirelessly transmit over network  23  event fault codes upon an event fault code occurrence to server  18 , rather than store the event fault codes in the OBEED system. When the event fault code is triggered, a message is sent to server  18 , which is programmed to retrieve log file  24  of the engine operating parameters and component commands that correlates with the timing of the event fault code. In this manner, when an event fault code occurs, the information necessary to determine a root cause of the event fault code occurrence is automatically captured and wirelessly transmitted to log file  24 , without any operator/driver or repair facility intervention. 
     In one configuration, ring buffer  32  is configured to capture engine operating parameters and component commands data for a predetermined time segment that is sufficient to provide the data prior to the fault code event occurring, as well as for a predetermined time segment after the fault code event. This information is essentially the same information that is traditionally captured by hardwiring the engine controller  20  to a diagnostic tool and driving vehicle  12  to duplicate the fault code event by a repair technician after the initial engine code event has occurred. However, because the engine operating information is captured in real-time and automatically correlated to the event fault code, time for diagnostic testing is significantly reduced and/or eliminated as this information may be electronically transmitted to log file  24  in server  18 . 
     Moreover, with fault code event, engine operating parameters and component commands data transmitted and captured in log file  24 , this collective data may then be accessed, either directly through a hardwire connection to server  18 , or alternatively, remotely through a web portal operatively connected to server  18 , and reviewed to determine the root cause of the event fault code. Identification of the root cause of the fault code event enables remote and timely development of a repair plan for vehicle  12 . The repair plan may also include ordering any necessary parts for carrying out any necessary repairs. Log file  24  and the repair plan may also be compiled together into a repair package for transmission to a selected repair facility  30 . For example, the repair package may be electronically transmitted to a desired repair facility  30  across network  23  via satellite  26  or cellular tower  28 . 
     Because repair specialists may be able to access the repair package information stored on server  18  prior to vehicle  12  reaching repair facility  42 , the repair specialists may employ a proactive service approach by identifying the service procedure and parts required for performing the repair, all before vehicle  12  arrives at the repair facility. 
     In accordance with another aspect of the disclosure, vehicle  12  may also configured with a telematics system  40  that tracks vehicle movement, driver hours, and motion and time related metrics. In one arrangement, telematics system  40  tracks an entire fleet of vehicles  12  such that the location of every vehicle  12  within the fleet is readily identifiable. In one exemplary arrangement, telematics system  40  is also supported by server  18  and receives information concerning each vehicle  12  via satellite  26  and/or cellular tower  28  over wireless network  23 . When an event fault code occurs, log file  24  and the stored code event faults may be correlated with information from telematics system  40 , to identify the closest available repair facility  30 . 
     Use of communication data scheme  10  and creation of the repair package will eliminate the diagnostic time to identify the root cause of a code event occurrence, increase repair quality, and allow repair facility  30  to obtain parts prior to vehicle  12  arrival, thereby allowing vehicle  12  to move from an assessment to repair and back on the road in the shortest period of downtime. 
     Referring to  FIG. 2 , an operation flow  100  of data communication system  10  will now be described. The exemplary operations in operation flow  100  may be performed periodically while vehicle  12  is being operated. While the exemplary operations are illustrated in a particular sequence in  FIG. 2 , it is understood that the exemplary operations may be performed in other sequences other than that shown in  FIG. 2 , depending upon the particular implantation. 
     Prior to operation flow  100 , it is assumed that engine operational parameter and component command data has been gathered from one or more electronically controlled systems. Gathering the engine operational parameter and component command data involves requesting engine operational parameter and component command data from the one or more electronically controlled systems in real-time. The engine operational parameter and component command data is requested by engine control module  20 . 
     Once engine operational parameter and component command data is collected, in step  102 , the engine operational parameter and component command data is wirelessly transmitted via data link  22  to a log file  24  in a remote server  18 . The transmission of engine operational parameter and component command data is continuously transmitted to ring buffer  32  in log file  24 . The engine operational parameter and component command data is stored in ring buffer  32  for a predetermined time. The flow continues to step  104 . 
     In step  104 , a determination is made if there has been a fault code event occurrence. If no fault code event has been triggered, the flow proceeds to step  106 . If a fault code event has been triggered, the flow proceeds to step  108 . 
     In step  106 , a portion of engine operational parameter and component command data is selectively deleted to make room for additional engine operational parameter and component command data to be temporarily stored in ring buffer  32 . More specifically, the oldest engine operational parameter and component command data is deleted from ring buffer  32  such that newer engine operational parameter and component command data may be stored. The flow then returns to step  102 . 
     In step  108 , once a fault code event is triggered, engine operational parameter and component command data saved in log file  24  on server  18 . In addition, in step  110 , the fault code associated with the fault code event is also saved in log file  24  on server  18 . Steps  108  and  110  may be performed simultaneously. The flow then proceeds to step  112 . 
     In step  112 , the log file  24  is then accessed by repair specialists. In one arrangement, log file  24  is made available via a web portal to repair specialist. In another arrangement, log file  24  is electronically transmitted to the repair specialist. Once the repair specialists access log file  24  and the triggering fault code, the repair specialists then determine the appropriate repair procedure, as well as any needed parts to repair vehicle  12  in step  114 . The flow then proceeds to step  116 . 
     In step  116 , the repair specialists compile a repair package containing the log file  24  and the recommended repair procedure. This repair package is then communicated to an appropriate repair facility. In one embodiment, a telematics system  40  is employed that determines the location of vehicle  12 . This location information is compared with various repair center locations so as to select the appropriate repair facility to direct vehicle  12 . Selection of an appropriate repair facility may depend on vehicle location, availability of parts required for the repair at the repair facilities, and availability of labor at the repair facility. For example, while telematics system  40  may determine that a vehicle  12  is located physically closer to a first repair facility  42   a , a second repair facility  42   b  may have the necessary parts required for the repair in stock, and have immediate labor availability to conduct the necessary repairs. In that instance, the repair package may be sent to the second repair facility  42   b . Once the repair has been made and vehicle is placed back in operation, flow  100  is reinitiated. 
     With regard to the processes, systems, methods, etc. described herein, it should be understood that, although the steps of such processes, etc. have been described as occurring according to a certain ordered sequence, such processes could be practiced with the described steps performed in an order other than the order described herein. It further should be understood that certain steps could be performed simultaneously, that other steps could be added, or that certain steps described herein could be omitted. In other words, the descriptions of processes herein are provided for the purpose of illustrating certain embodiments, and should in no way be construed so as to limit the claimed invention. 
     It is to be understood that the above description is intended to be illustrative and not restrictive. Many embodiments and applications other than the examples provided would be apparent to those of skill in the art upon reading the above description. The scope of the invention should be determined, not with reference to the above description, but should instead be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. It is anticipated and intended that future developments will occur in the arts discussed herein, and that the disclosed systems and methods will be incorporated into such future embodiments. In sum, it should be understood that the invention is capable of modification and variation and is limited only by the following claims. 
     All terms used in the claims are intended to be given their broadest reasonable constructions and their ordinary meanings as understood by those skilled in the art unless an explicit indication to the contrary in made herein. In particular, use of the singular articles such as “a,” “the,” “said,” etc. should be read to recite one or more of the indicated elements unless a claim recites an explicit limitation to the contrary. 
     The words used herein are words of description, not words of limitation. Those skilled in the art recognize that many modifications and variations are possible without departing from the scope and spirit of the invention as set forth in the appended claims.