Patent Publication Number: US-6216069-B1

Title: Hidden acquisition module for acquiring data from a vehicle

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates generally to a data acquisition device and, more particularly, to a miniature non-volatile data acquisition module to be mounted in an inconspicuous location on a vehicle to acquire event and duration data from an electrical vehicle component for an extended period of time. 
     2. Discussion of the Related Art 
     Many vehicle components and devices are tested to insure that they operate according to predetermined specifications. It may be desirable in certain cases to monitor the operation of the vehicle component over an extended period of time, for example up to three years, to determine the number of times the device is activated and the length of each operation, to monitor device longevity and reliability. For example, it may be desirable to monitor the operation of a vehicle starter over an extended period of time to determine the number of times the vehicle starter is activated, and the duration of each start, so that the starter can be reliable for the life of the vehicle. 
     In order to monitor a vehicle component for an extended period of time, it would be desirable to have the monitoring device mounted at an inconspicuous location on the vehicle so that it does not interfere with the everyday operation of the vehicle. In order to allow the monitoring device to be inconspicuously mounted to the vehicle during normal vehicle operation, it is necessary that the device be small in size. Also, it would be desirable if the monitoring device would only draw a small amount of current during operation. Further, because of the length of the testing period, it is necessary that the monitoring device retain its data even if the vehicle battery is drained or removed. 
     Known data acquisition devices for monitoring and testing vehicle components typically are large devices that cannot be inconspicuously located in the vehicle, do not retain data if the vehicle battery is removed, are expensive, and have mechanical parts. These known data acquisition devices are thus not suitable for long term data acquisition of the type described above. 
     What is needed is a small, cost effective data acquisition device that is readily mounted to a vehicle in an inconspicuous location, and is capable of monitoring electrical events and their duration for a long period of time without losing data from loss of vehicle power. It is therefore an object of the present invention to provide such a data acquisition module. 
     SUMMARY OF THE INVENTION 
     In accordance with the teachings of the present invention, a hidden acquisition module (HAM) is disclosed that is compact, non-volatile, and readily mounted at an inconspicuous location in the vehicle to provide electrical monitoring of the operation of a particular vehicle component for an extended period of time. The HAM monitors the particular vehicle component, and stores each activation of the component and its duration in an electrically erasable programmable read-only memory (EEPROM) to be downloaded at a future time. In one embodiment, a microprocessor and a bank of EEPROMs are provided, where the count is stored in the microprocessor and the duration is stored in the bank of EEPROMs. The address of a particular EEPROM in the bank is the location of where an event duration is stored. 
     Additional objects, advantages and features of the present invention will become apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a data acquisition module, according to an embodiment of the present invention; 
     FIG. 2 is a schematic diagram showing a microprocessor and other electrical components associated with the electrical circuitry of the data acquisition module shown in FIG. 1; 
     FIG. 3 is a schematic diagram of the remaining components of the electrical circuitry of the data acquisition module of the invention, including a bank of EEPROMs; and 
     FIG. 4 is an electrical board layout of the components of the data acquisition module shown in FIG.  1 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The following discussion of the preferred embodiments directed to a data acquisition module for monitoring an electrical vehicle component is merely exemplary in nature, and is in no way intended to limit the invention or its applications or uses. For example, the discussion below refers to monitoring the operation of the vehicle starter motor, but as will be appreciated by those skilled in the art, the module of the present invention has a much wider application for monitoring other vehicle components, such as activation of the vehicle brakes, doors, lights, etc. 
     FIG. 1 is a perspective view of a hidden acquisition module (HAM)  10  for monitoring an electrical vehicle component, such as a vehicle starter motor, according to the invention. The HAM  10  includes an outer housing  12  that encloses the electrical components of the HAM  10 , and a pair of mounting tabs  14  and  16  that allow the HAM  10  to be mounted by screws or the like to the vehicle at an inconspicuous location, such as under the vehicle dash-board. Three wires extend through a circular opening (not shown) in the housing  12  and are connected to the electrical circuitry within, as will be discussed below. A first wire  18  provides power to the HAM  10  from the vehicle battery, a second wire  20  is a ground connection to the HAM  10 , and a third wire  22  provides the electrical data input to the HAM  10  that is connected to an electrical output of the vehicle component (not shown) being monitored. Also, an opening  24  through the housing  12  provides access to an RJ 45  connector within the housing  12 . In one embodiment, the housing  12  has a length of about two inches, a width of about one and a half inches and a height of about one inch. The overall length of the HAM  10  with the mounting tabs  14  and  16  is about 2.875 inches. 
     FIG. 2 is a schematic diagram of an electrical circuit  26  showing some of the electrical components of the HAM  10 . The electrical components including a 24-pin BS2 Stamp® microprocessor  28  that is available from Parallax, Inc. The microprocessor  28  includes a PIC processor, a voltage regulator, an electrically erasable programmable read only memory (EEPROM), a crystal, an RS 232  interface chip and other electrical support components, as is known in the art. Each pin is labeled, where pins  5 - 20  are input/output ports P 0 -P 15 . Pins  9 - 11  and  13 - 20  are connected to electrical pads  30 , and are unused input/output ports in this embodiment. Pin  22  is a reset port that resets the microprocessor  28  and pin  24  is not connected. 
     In one embodiment, the HAM  10  is programmed using PBASIC commands. The program is downloaded to the EEPROM in the microprocessor  28 , and may provide a no current draw until the system is activated, or if continuous monitoring is done, power saving features of the microprocessor  28  may be used to reduce the power consumption. The microprocessor  28  clocks each event occurrence with a resolution of 0.1 seconds, in one embodiment. The spare input/output ports at pins  9 - 11  and  13 - 20  can be programmed to provide serial communications to other microprocessors, serial memory or monitor other points of interest. Programming highlights of the microprocessor  28  include sleep functions, pulse in/out, pulse width modulation, button debounce, shift in/out, RC time constant, sound, and EEPROM access. 
     Pins  1 - 4  are for a dedicated serial port and are connected to pins  1 - 4  of an eight pin RJ 45  connector (see FIG. 4) at electrical pads  32 , labeled J 1   1 - 8 . The RJ 45  connector is used to program the microprocessor  28  through pins  1 - 4 , where the program is stored in the EEPROM on the microprocessor  28 , and can be electrically erased and reprogrammed as desired. Pin  12  of the microprocessor  28  is connected to pin  7  of the RJ 45  connector, and is the output port from the microprocessor  28  that the data is retrieved from the HAM  10 , as will be discussed below. Pin  6  of the RJ 45  connector is connected to pin  8  of the microprocessor  28 , and is an indication input to tell the microprocessor  28  to output the stored data. When pin  8  of the microprocessor  28  goes high, the data is output at pin  12 . Pin  8  of the RJ 45  connector is connected to a +5 voltage potential, and pin  5  of the RJ 45  connector is connected to ground. 
     The wire  20  is connected to pad  36 , which is connected to pin  23  of the microprocessor  28  to provide the ground connection. Wire  18  is connected to pad  38 , which is connected to an input pin of a 5 V voltage regulator  40 . The voltage regulator  40  regulates the input voltage from the 12 volt vehicle battery to the 5 volts that operates the HAM  10 . The output pin of the voltage regulator  40  is connected to a capacitor C 1  and pin  21  of the microprocessor  28 . If the voltage of the vehicle battery varies, for example, from 6 V-30 V DC, the regulator  40  provides the regulated 5 V source. The wire  22  is connected to pad  42 , which is connected to a voltage divider network  44  made up of resistors R 8  and R 9 . A zener diode D 1  protects the microprocessor  28  from voltage spikes that may occur from the vehicle component being tested. Therefore, when a high signal from the vehicle component being monitored is applied to the wire  22 , the voltage divided signal is applied to pin  7  of the microprocessor  28 . As long as the starter motor is energized, pin  7  is high. The high signal at pin  7  of the microprocessor  28  provides the data to determine event detection and duration of the vehicle function. 
     FIG. 3 is a schematic diagram of a bank of eight EEPROMs  50 ,  52 ,  54 ,  56 ,  58 ,  60 ,  62  and  64  connected in parallel and each having 8 pins. The EEPROMs  50 - 64  provide a 512K bit non-volatile memory that is easily addressed as one large block of 64K by 8 or any combination of 8K by 8 blocks to store data. Pin  8  of each of the EEPROMs  50 - 64  is connected to the 5 V potential, pin  4  of each of the EEPROMs  50 - 64  is connected to ground, and pin  7  of each of the EEPROMs  50 - 64  is not connected to anything. A data output signal at pin  5  of the microprocessor  28  is applied to pin  5  of each of the EEPROMs  50 - 64 , and a clock signal from pin  6  of the microprocessor  28  is applied to pin  6  of each of the EEPROMs  50 - 64 . As is apparent, each of the pins  1 - 3  of the EEPROMs  50 - 64  is connected differently to the 5 V potential and ground, where each connection of the pins  1 - 3  identifies the address of the particular EEPROM  50 - 64 . 
     When the starter motor is activated, the signal on line  22  is voltage divided by the voltage divider  44 , and applied to pin  7  of the microprocessor  28  as a high signal. The program within the microprocessor  28  continually monitors pin  7 , and when pin  7  goes high, the program goes into a sub-routine that provides a duration count at the programmed resolution. When pin  7  goes low indicating the end of the event, the microprocessor  28  increments an event counter to show that the event occurred. In one embodiment, for each event duration, the microprocessor  28  determines if that duration was one of the longest 25 events. If the event is longer than the last top 25 events, the microprocessor  28  will update a top 25 lists in the microprocessor&#39;s EEPROM. The actual count or the number of the event is stored in the EEPROM in the microprocessor  28 , and this number represents the address of a particular EEPROM  50 - 64 . The memory size of the EEPROM on the microprocessor  28  gives memory space for 65,535 events. When the event stops, the microprocessor  28  outputs at pin  5  the current event count as the address of the EEPROM  50 - 64  and the duration of the event in a serial data string. This data is received at pin  5  of each of the EEPROMs  50 - 64 , and the EEPROM  50 - 64  that has the address represented by the event number stores the duration data. The count data stored in the microprocessor  28  is such that the EEPROMs  50 - 64  are filled with duration data in a systematic manner. Because the EEPROMs  50 - 64  and the EEPROM in the microprocessor  28  are non-volatile, the data is not lost if the vehicle battery is drained or removed. 
     When a high signal at pin  6  of the RJ 45  connector is applied to pin  8  of the microprocessor  28 , the program acts to reverse the process. For each event count stored in the EEPROM of the microprocessor  28 , the duration of that event is downloaded from the EEPROM  50 - 64  having the address of that count through pin  5  of the microprocessor  28 , including the top 25 longest durations. 
     FIG. 4 shows a top plan view of an electrical circuit board  68  on which is mounted the electrical components of the HAM  10 . Each of the pads  30  (PD 1 -PD 12 ) for ports  4 - 6  and  13 - 20  are provided so that these pads can be used in alternate embodiments. The pads PDI 1 -PDI 3  are provided on the board  68  to connect the wires  18 ,  20  and  22 . The EEPROMs  50 - 60  are mounted on the board  68  beneath the microprocessor  28 . An RJ 45  connector  70  is mounted to the board  68 , and is the eight pin connector discussed above. The connector  70  is accessible through the opening  24 . 
     The foregoing discussion discloses and describes merely exemplary embodiments of the present invention. One skilled in the art will readily recognize from such discussion, and from the accompanying drawings and claims, that various changes, modifications and variations can be made therein without departing from the spirit and scope of the invention as defined in the following claims.