U.S. patent application number 10/419649 was filed with the patent office on 2003-10-16 for equipment service vehicle having on-board diagnostic system.
This patent application is currently assigned to Oshkosh Truck Corporation. Invention is credited to Pillar, Duane R..
Application Number | 20030195680 10/419649 |
Document ID | / |
Family ID | 23989710 |
Filed Date | 2003-10-16 |
United States Patent
Application |
20030195680 |
Kind Code |
A1 |
Pillar, Duane R. |
October 16, 2003 |
Equipment service vehicle having on-board diagnostic system
Abstract
An equipment service vehicle comprises a network communication
link, an engine system, a transmission system, and an operator
interface. The engine system includes an engine and an electronic
engine control system that is coupled to the engine and to the
network communication link. The electronic engine control system
controls the engine and transmits information pertaining to the
health and operation of the engine on the network communication
link. The transmission system includes a transmission and an
electronic transmission control system. The electronic transmission
control system controls the transmission and transmits information
pertaining to the health and operation of the transmission on the
network communication link. The operator interface is coupled to
the network communication link. The operator interface includes a
display that displays the health and operation information of the
engine and the transmission to a human operator.
Inventors: |
Pillar, Duane R.; (Oshkosh,
WI) |
Correspondence
Address: |
FOLEY & LARDNER
777 EAST WISCONSIN AVENUE
SUITE 3800
MILWAUKEE
WI
53202-5308
US
|
Assignee: |
Oshkosh Truck Corporation
|
Family ID: |
23989710 |
Appl. No.: |
10/419649 |
Filed: |
April 21, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10419649 |
Apr 21, 2003 |
|
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09500506 |
Feb 9, 2000 |
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6553290 |
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Current U.S.
Class: |
701/31.4 ;
340/438 |
Current CPC
Class: |
G07C 5/085 20130101;
G01M 17/00 20130101; G07C 5/008 20130101 |
Class at
Publication: |
701/33 ; 701/29;
340/438 |
International
Class: |
G06F 019/00 |
Claims
What is claimed is:
1. An equipment service vehicle comprising: (A) a network
communication link; (B) a plurality of vehicle subsystems; (C) a
sensor, the sensor being configured to obtain health and operation
information for a vehicle device; (D) an on-board diagnostic system
including an on-board test control module and an on-board operator
interface, the on-board operator interface displaying a plurality
of test options to an operator and receiving a selection of a test
from the operator, the test control module being connected to at
least some of the plurality of vehicle subsystems by way of the
network communication link, the on-board test control module
transmitting a request for information pertaining to the health and
operation of the vehicle device on the network communication link;
and (E) a test interface module, the test interface module being
connected to the sensor, the test interface module being connected
to the on-board test control module by way of the network
communication link, the test interface module receiving the request
for information pertaining to the health and operation of the
vehicle device, the test interface module acquiring the requested
information from the sensor and transmitting the requested
information to the test control module; and wherein the test
control module receives health and operation information from one
of the respective vehicle subsystem or the test interface module or
both and wherein the operator interface displays results of the
test to the operator; wherein the selection is a first selection
and the test is a first test, wherein the operator interface
receives a plurality of additional selections of a plurality of
additional tests, and wherein the operator interface displays
results of the plurality of additional tests to the operator.
2. A diagnostic testing method to be executed by an on-board
diagnostic system of an equipment service vehicle having a
plurality of subsystems, the method comprising: displaying a
plurality of test options to an operator using an on-board operator
interface, the operator interface being connected to a test control
module; receiving an operator input using the operator interface,
the input being indicative of a selection made by the operator, the
selection indicating a test selected by the operator; performing
the selected test on the vehicle using a sensor or at least one of
the plurality of vehicle subsystems or both, the plurality of
subsystems being connected to the test control module by way of a
network communication link, the sensor being configured to obtain
health and operation information for a vehicle device, the sensor
being connected to a test interface module that is connected to the
network communication link; acquiring health and operation
information pertaining to results of the test from the at least one
vehicle subsystem or from the test interface module using the
sensor or from both; transmitting the health and operation
information from the test interface module or the at least one
vehicle subsystem or both to the test control module by way of the
network communication link; displaying the results of the test to
the operator using the operator interface; and wherein the test is
a first test, and wherein the foregoing steps are repeated such
that results of a plurality of additional tests are displayed.
3. A military vehicle comprising: a plurality of subsystems, an
on-board diagnostic system, the on-board diagnostic system
including an operator interface, a test control module, a test
interface module, and a sensor, the operator interface being
connected to the test control module, the sensor being connected to
the test interface module, the test control module being connected
to the test interface module and to the plurality of subsystems by
way of a network communication link, the operator interface being
at least semi-permanently mounted on-board the vehicle, the test
control module being programmed to cooperate with the operator
interface, the sensor, the test interface module, and the plurality
of subsystems to display a plurality of test options to an operator
using the operator interface; receive an operator input using the
operator interface, the input being indicative of a selection made
by the operator, the selection indicating a test selected by the
operator; perform the selected test on the vehicle using the sensor
or at least one of the plurality of vehicle subsystems or both, the
sensor being configured to obtain health and operation information
for a vehicle device; acquire health and operation information
pertaining to results of the test from the at least one vehicle
subsystem or from the test interface module using the sensor or
from both; transmit the health and operation information from the
test interface module or the at least one vehicle subsystem or both
to the test control module by way of the network communication
link; and display the results of the test to the operator using the
operator interface; and wherein the military vehicle is capable of
travelling on unimproved terrain and through at least three feet of
water.
4. A military vehicle according to claim 3, wherein the plurality
of vehicle subsystems include an engine system including an engine
control system and a transmission system including a transmission
control system, wherein the engine control system and the
transmission control system are each capable of producing fault
codes and transmitting the fault codes on the network communication
link, and wherein the test control module and the operator
interface in combination are capable of receiving the fault codes
from the network communication link and displaying the fault codes
to a human operator.
5. A military vehicle according to claim 4, wherein the fault codes
are displayed in an interpreted format.
6. A military vehicle according to claim 3, wherein the on-board
diagnostic system stores a vehicle maintenance record, the vehicle
maintenance record comprising a descriptive log of maintenance
activities performed on the vehicle.
7. A military vehicle according to claim 3, further comprising a
memory that stores a running log of health and operation
information pertaining to the vehicle.
8. A military vehicle according to claim 3, wherein the test
interface module is a separate unit from the sensor.
9. A military vehicle according to claim 3, wherein the operator
interface and the test control module are provided as a single
integrated unit.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of U.S. Ser. No.
09/500,506, filed Feb. 9, 2000, now U.S. Pat. No. 6,553,290, issued
Feb. 22, 2003, hereby incorporated by reference.
FIELD OF THE INVENTION
[0002] This invention relates to diagnostic systems for equipment
service vehicles. In particular, this invention relates to an
on-board diagnostic system for equipment service vehicles.
DESCRIPTION OF RELATED ART
[0003] Modern vehicles have become increasingly complex and
difficult to maintain. In order to enable more efficient vehicle
maintenance, it is desirable to be able to accurately diagnose
malfunctioning subsystems, such as engine systems, transmission
systems, and so on, as well as specific vehicle components. When a
malfunction is not properly diagnosed, the result is typically that
parts which are fully operational are repaired or replaced, that
parts which are repairable are replaced, and/or that parts which
are not fully operational are not repaired or replaced. Accurate
diagnoses therefore allow more efficient vehicle maintenance by
avoiding unnecessary repairs and replacements, and by enabling
necessary repairs and replacements to be made.
[0004] It is known to provide electronic diagnostic systems to aid
in the accurate diagnoses of vehicle malfunctions. Government
Report No. CR-82-588-003, entitled "STE/ICE-R Design Guide For
Vehicle Diagnostic Connector Assemblies," February 1988, describes
a diagnostic system used in connection with military vehicles.
According to the approach described in this document, a military
vehicle is provided with numerous sensors that are located
throughout the vehicle and each of which obtains information
pertaining to the health and operation of a subsystem of the
vehicle. The sensors are used to measure typical parameters of
interest such as engine RPM, engine temperature, fuel pressure, and
so on. The sensors are connected by way of vehicle wiring to a
common connector assembly. Diagnostic equipment provided at a
maintenance depot is then capable of connecting to the various
sensors by way of the connector assembly. At the maintenance depot,
the diagnostic equipment can be utilized to perform tests on the
vehicle to aid pinpointing the source of vehicle system
malfunction.
[0005] In this arrangement, the sensors that are used by the
diagnostic system are used exclusively by the diagnostic equipment
at the maintenance depot, and not by other systems during normal
operation of the vehicle. Additionally, in this arrangement, the
connector assembly defines a hardwired analog interface between the
sensors and the diagnostic equipment, and the diagnostic equipment
expects signals appearing at given pins of the connector assembly
to have predefined signal characteristics that are unique to the
sensor utilized.
[0006] This approach suffers several disadvantages. First, this
approach is expensive to implement because it requires numerous
sensors above and beyond those required for normal operation of the
vehicle. Additionally, the required sensors typically have unique
signal characteristics that are specifically matched to the
diagnostic equipment, and therefore the sensors are specialty items
that are more expensive and not commonly available.
[0007] Second, this approach results in a diagnostic system with an
unduly limited capability to accurately diagnose system faults. The
capabilities of the diagnostic system are limited by the fact that
the diagnostic system only utilizes information that is available
from the diagnostic system sensors and not from other sources of
information available on-board the vehicle. Therefore, the number
of different types of information that can be obtained is limited
to the number of diagnostic system sensors utilized. Further,
because the sensors that are utilized tend to be specialty items as
previously noted, they often do not incorporate the latest advances
in sensor technology that provide performance/durability
improvements over earlier sensor technologies. This further limits
the accuracy of the diagnostic system as compared to that which
could otherwise be achieved.
[0008] Finally, this approach is unduly cumbersome to utilize. As
previously noted, the diagnostic equipment is provided at a
maintenance depot and not on-board the vehicle. Therefore, in order
to have a vehicle malfunction diagnosed, the vehicle must be
brought to the maintenance depot. This requirement is inconvenient
and limits the potential for field servicing of vehicles to
minimize the amount of time that the vehicle is out of service for
maintenance reasons.
SUMMARY OF THE INVENTION
[0009] The present invention overcomes the problems of conventional
diagnostic systems for equipment service vehicles. In particular,
in one particularly preferred embodiment, the invention provides an
equipment service vehicle comprising a network communication link,
a plurality of vehicle subsystems, a test control module, and an
operator interface. The vehicle subsystems each comprise a
mechanical system and an electronic control system that controls
the mechanical system. For example, one vehicle subsystem may
comprise an engine and an engine control system, and another
vehicle subsystem may comprise a transmission and a transmission
control system. Each respective electronic control system is
connected to the network communication link and transmits
information pertaining to the health and operation of the
associated mechanical system on the network communication link. The
test control module is coupled to the plurality of vehicle
subsystems by way of the network communication link. The test
control module is programmed to acquire at least some of the
information pertaining to the health and operation of the
mechanical system. The operator interface is coupled to the test
control module and comprises a display that displays the at least
some information pertaining to the health and operation of the
mechanical system.
[0010] According to another particularly preferred embodiment of
the invention, the invention provides a method of diagnosing a
fault on an equipment service vehicle comprising providing the
equipment service vehicle with an on-board diagnostic system. The
on board diagnostic system comprises a test control module and an
operator interface that are mounted on the vehicle. The method also
comprises displaying a menu of test options to an operator using
the operator interface and receiving an operator input using the
operator interface. The input is indicative of a menu selection
made by the operator, and the menu selection indicates a test
selected by the operator to be performed on the vehicle. Further,
the method comprises performing the selected test on the vehicle in
response to the operator input, and displaying results of the test
to the operator using the operator interface.
[0011] According to yet another particularly preferred embodiment
of the invention, the invention provides an equipment service
vehicle comprising a network communication link, an engine system,
a transmission system, and an operator interface. The engine system
includes an engine and an electronic engine control system that is
coupled to the engine and to the network communication link. The
electronic engine control system controls the engine and transmits
information pertaining to the health and operation of the engine on
the network communication link. The transmission system includes a
transmission and an electronic transmission control system. The
electronic transmission control system controls the transmission
and transmits information pertaining to the health and operation of
the transmission on the network communication link. The operator
interface is coupled to the network communication link and includes
a display that displays the health and operation information of the
engine and the transmission to a human operator.
[0012] Other objects, features, and advantages of the present
invention will become apparent to those skilled in the art from the
following detailed description and accompanying drawings. It should
be understood, however, that the detailed description and specific
examples, while indicating preferred embodiments of the present
invention, are given by way of illustration and not limitation.
Many modifications and changes within the scope of the present
invention may be made without departing from the spirit thereof,
and the invention includes all such modifications.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a schematic view of a military vehicle having a
diagnostic system according to one embodiment of the present
invention;
[0014] FIG. 2 is a block diagram of the diagnostic system of FIG. 1
showing selected aspects of the diagnostic system in greater
detail;
[0015] FIG. 3 is a menu displayed by a display of the diagnostic
system of FIG. 1 showing various services offered by the diagnostic
system;
[0016] FIG. 4 is a flow chart showing the operation of the
diagnostic system of FIG. 1 to perform a diagnostic test
procedure;
[0017] FIG. 5 is a schematic view of a firefighting vehicle having
a diagnostic system in accordance with FIGS. 1-4;
[0018] FIG. 6 is a schematic view of a mixing vehicle having a
diagnostic system in accordance with FIGS. 1-4;
[0019] FIG. 7 is a schematic view of a refuse handling vehicle
having a diagnostic system in accordance with FIGS. 1-4; and
[0020] FIG. 8 is a schematic view of a snow removal vehicle having
a diagnostic system in accordance with FIGS. 1-4.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0021] Referring now to FIG. 1, a preferred embodiment of an
equipment service vehicle 10 having a diagnostic system 12
according to an embodiment of the invention is illustrated. By way
of overview, the diagnostic system 12 comprises an intelligent
display module 14, a test interface module 21 connected to a
plurality of sensors 22, and a plurality of additional vehicle
control systems 24-30. The intelligent display module 14, the test
interface module 21, and the plurality of additional vehicle
control systems 24-30 are interconnected with each other by way of
a network communication link 32.
[0022] More specifically, the vehicle 10 is a military vehicle and,
in particular, a medium tactical vehicle. However, it should be
understood that the diagnostic system 12 of FIG. 1 could also be
used with other types of military vehicles. For example, the
diagnostic system 12 could be used in connection with heavy
equipment transporter vehicles, which are used to transport battle
tanks, fighting and recovery vehicles, self-propelled howitzers,
construction equipment and other types of equipment. These types of
vehicles are useable on primary, secondary, and unimproved roads
and trails, and are able to transport in excess of 100,000 pounds
or even in the range of 200,000 pounds or more. The diagnostic
system 12 can also be used in connection with palletized load
transport vehicles, in which a mobile truck and trailer form a
self-contained system capable of loading and unloading a wide range
of cargo without the need for forklifts or other material handling
equipment. Such trucks are provided with a demountable cargo bed
and a hydraulically powered arm with a hook that lifts the cargo
bed on or off the truck. These trucks may be also provided with a
crane to drop off the pallets individually if the entire load is
not needed. Further, the diagnostic system 12 can also be used in
connection with trucks designed for carrying payloads for cross
country military missions. Such trucks may include, for example,
cargo trucks, tractors, fuel servicing trucks, portable water
trucks, and recovery vehicles (with crane and winch). Such trucks
are capable of passing through water crossings three or four or
more feet deep. These trucks can also be used for missile
transports/launchers, resupply of fueled artillery ammunition and
forward area rearm vehicles, refueling of tracked and wheeled
vehicles and helicopters, and recovery of disabled wheeled and
tracked vehicles. The diagnostic system 12 can be used in
connection with a wide range of other military vehicles as
well.
[0023] The intelligent display module 14 provides an operator
interface to the diagnostic system 12 and also provides
intelligence used to conduct diagnostic tests and other services.
In particular, the intelligent display module 14 includes a test
control module 15 (which further includes a microprocessor 16 and a
diagnostic program 17) and an operator interface 18 (which further
includes a display 19 and a keypad 20) (see FIG. 2).
[0024] In the preferred embodiment, the test control module 15 and
the operator interface 18 are provided as a single, integrated unit
(namely, the intelligent display module 14) and share the same
housing as well as at least some of the internal electronics. Other
arrangements are possible, however. For example, as can be easily
imagined, it would also be possible to provide the test control
module 15 and the operator interface 18 in the form of separate
physical units, although this arrangement is not preferred for
reasons of increased cost and parts count. Both the test control
module 15 and the operator interface 18 can be obtained in the form
of a single, integrated unit from Advanced Technology, Inc.,
Elkhart, Ind. 46517. This product provides a generic flat panel 4
line.times.20 character display 19, four button keypad 20,
microprocessor 16, and memory that is capable of being programmed
with a program (such as the diagnostic program 17) to customize the
intelligent display module for a particular application. Of course,
a more (or less) elaborate intelligent display module could also be
utilized.
[0025] Also in the preferred embodiment, the intelligent display
module 14 is semi-permanently mounted within the vehicle 10. By
semi-permanently mounted, it is meant that the intelligent display
module 14 is mounted within the vehicle 10 in a manner that is
sufficiently rugged to withstand normal operation of the vehicle
for extended periods of time (at least days or weeks) and still
remain operational. However, that is not to say that the
intelligent display module 14 is mounted such that it can never be
removed (e.g., for servicing of the intelligent display module)
without significantly degrading the structural integrity of the
mounting structure employed to mount the intelligent display module
14 to the remainder of the vehicle 10. The intelligent display
module 14 is preferably mounted in an operator compartment of the
vehicle 10, for example, in a storage compartment within the
operator compartment or on an operator panel provided on the
dashboard.
[0026] The operation of the test control module 15, and in
particular of the microprocessor 16 to execute the diagnostic
program 17, is shown and described in greater detail below in
conjunction with the flow chart of FIG. 4. In general, the
microprocessor 16 executes the diagnostic program 17 to diagnose
subsystem faults, to display fault information, to maintain vehicle
maintenance records, and to perform data logging for system
diagnosis and/or for accident reconstruction. Depending on the
application, it may be desirable to incorporate additional services
as well, or to incorporate fewer than all of these services.
[0027] The operator interface 18 includes the display 19 which is
used to communicate (and, in particular, to display) information to
the operator. For example, the display 19 is used to prompt the
operator to enter information into the keypad 20, or to take
certain actions with respect to the vehicle during testing (e.g.,
bring the engine to a specified RPM level). The display 19 is also
used to display a menu or series of menus to allow the operator to
select a test to be performed or to select another service of the
intelligent display module 14 to be utilized. The display 19 is
also used to display status information during system startup and
during testing, and to display any error messages that arise during
system startup or during testing. The display 19 is also used to
display input data and fault mode indicators from control systems
24-30, and any other information from additional vehicle
subsystems. The display 19 is also used to display information from
discrete sensors such as the sensors 22. The display 19 is also
used to display the results of diagnostic tests that are performed
(e.g., a pass/fail message or other message).
[0028] Preferably, the display 19 displays all of this information
to the operator in a user-friendly format as opposed to in the form
of codes that must be interpreted by reference to a separate test
or service manual. This is achieved in straightforward fashion by
storing in the memory of the intelligent display module 14
information of the type commonly published in such manuals to
facilitate manual interpretation of such codes, and using this
information to perform the translation automatically. Likewise, as
previously noted, the display 19 is used to prompt the operator to
take certain actions with respect to the vehicle during testing and
to otherwise step the operator through any test procedures, without
reference to a test manual. This allows the amount of operator
training to be reduced.
[0029] The operator interface 18 also includes the keypad 20 which
is used to accept or receive operator inputs. For example, the
keypad 20 is used to allow the user to scroll through and otherwise
navigate menus displayed by the display 19 (e.g., menus of possible
tests to be performed on the vehicle 20), and to select menu items
from those menus.
[0030] As previously noted, it would also be possible to utilize a
more elaborate intelligent display module. For example, a more
elaborate keypad 20 could be utilized if more data entry capability
is desired. In this regard, however, it is noted that the
intelligent display module 14 also preferably includes a
communication port that allows the display module to communicate
with a personal computer 33 by way of a communication link 36 (see
FIG. 2). The personal computer 33 can be used to retrieve,
manipulate and examine data stored within the intelligent display
module 14. For example, if the intelligent display module 14
includes a data logger as described below, the personal computer
can be used to retrieve and examine the information stored by the
data logger. Likewise, if the intelligent display module 14
implements a vehicle maintenance jacket, the personal computer 33
can be used to retrieve and modify data stored in the vehicle
maintenance jacket. Further, using the personal computer 33, it is
possible to integrate the diagnostic system 12 with an interactive
electronic technical manual (IETM), to allow the interactive
electronic technical manual to access the data available from the
diagnostic system 12.
[0031] The test interface module 21 accepts requests from the
intelligent display module 14 for information from the sensors 22,
retrieves the requested information from the respective sensor 22,
converts input signals from the respective sensor 22 into a format
that is compatible with the network communication link 32, and
transmits the information from the respective sensor 22 to the
intelligent display module 14 via the network communication link
32. The test interface module 21 is therefore preferably
implemented as a passive unit with no standard broadcasts that
burden the communication link 32. As a result, in operation, the
test interface module 21 does not regularly transmit data on the
network communication link 32. Rather, the test interface module 21
passively monitors the network communication link 32 for
information requests directed to the interface module 21. When an
information request is received, the test interface module 21
obtains the requested information from the relevant sensor 22, and
then transmits the requested information on the network
communication link 32 to the intelligent display module 14.
[0032] The test interface module 21 may, for example, include as
many inputs as there are sensors 22. Each input may include
associated switches for configuring the input, an analog-to-digital
converter to convert analog signals to a digital format, and any
other signal processing circuitry. The number of inputs is not
important, since it is possible to use fewer test interface modules
each with a larger number of inputs, or more test interface modules
each with a smaller number of inputs. The number of inputs is not
limited in any particular way and is determined by need.
[0033] In practice, the test interface module 21 may be a
commercially available unit capable of putting information from
discrete sensors onto a network communication link such as SAE
(Society of Automotive Engineers) J1708. The test interface module
21 preferably also meets applicable standards for underhood
installation, such as SAE J1455, to allow the test interface module
to be located in close proximity to the sensors 22 to reduce
wiring. The test interface module may, for example, be obtained
from Advanced Technology Inc., Elkhart, Ind. 46517 (PN 3246282).
Again, however, a wide range of devices of varying construction and
complexity could be utilized to implement the test interface module
21.
[0034] The test interface module 21 is connected to the plurality
of sensors 22 which are each capable of obtaining information
pertaining to the health and operation of a vehicle subsystem.
"Health" and "operation" are interrelated and information that
pertains to one will, at least to some extent, pertain to the other
as well. The sensors 22 are discrete sensors in the sense that they
are not integrally provided with the control systems 24-30 and
associated controlled mechanical systems (e.g., engine,
transmission, and so on) 34-40. The sensors are add-on devices that
are used only in connection with the intelligent display module 14.
In general, discrete sensors are preferably only used when the
information provided by the sensor is not otherwise available on
the network communication link 32. In FIG. 2, the sensors 22 are
shown to include a fuel filter inlet pressure sensor 22a, fuel pump
outlet pressure sensor 22b, fuel return pressure sensor 22c, oil
filter sensors 22d, an air cleaner pressure sensor 22e, a fuel
differential pressure switch 22f, and a shunt resistor 22g (used to
determine compression imbalance based on unequal current peaks in
the starter current).
[0035] In addition to the intelligent display module 14 and the
test interface module 21, the diagnostic system 12 also includes a
plurality of additional vehicle control systems 24-30, as
previously noted. As shown in FIG. 2, the control system 24 is a
central tire inflation control system that controls a central tire
inflation system (CTIS) 34, the control system 26 is an anti-lock
brake control system that controls an anti-lock brake system (ABS)
36, the control system 28 is a transmission control system that
controls a transmission 38, and the control system 30 is an engine
control system that controls an engine 40. The vehicle subsystems
formed by the mechanical systems 34-40 and associated control
systems 24-30 are conventional and are chosen in accordance with
the intended use of the vehicle 10.
[0036] The control systems 24-30 each store information pertaining
to the health and operation of a respective controlled system. The
control systems 24-30 are capable of being queried and, in
response, making the requested information available on the network
communication link 32. Because the vast amount of information
required for performing most diagnostic tests of interest is
available from the control systems 24-30 by way of the network
communication link 32, it is possible to drastically reduce the
number of discrete sensors 22 that are required. Thus, as just
noted, discrete sensors are preferably only used when the
information provided by the sensor is not otherwise available on
the network communication link 32.
[0037] Typically, each of the control systems 24-30 comprises a
microprocessor-based electronic control unit (ECU) that is
connected to the network communication link 32. When the
intelligent display module 14 requires status information
pertaining to one of the mechanical systems 34-40, the intelligent
display module 14 issues a request for the information to the
respective one of the control systems 24-30. The respective control
system then responds by making the requested information available
on the network communication link 32.
[0038] Typical ECUs for transmission and engine control systems are
capable of producing fault codes and transmitting the fault codes
on the network communication link 32. Depending on the type of
fault, the fault codes may be transmitted automatically or
alternative only in response to a specific request for fault
information. Typical ECUs for central tire inflation systems and
anti-lock brake systems also transmit fault codes but, in most
commercially available systems, fault codes are transmitted only in
response to specific requests for fault information. When a fault
code is transmitted on the network communication link 32, the
intelligent display module 14 receives the fault codes from the
network communication link 32, interprets the fault codes, and
displays the interpreted fault codes to a human operator using the
display 19.
[0039] Referring now to FIG. 3, in general, during operation, the
display 19 displays menus to the operator and the keypad receives
operator inputs used to navigate the menu, make menu selections,
and begin testing. Assuming other services are also provided, the
operator is first prompted to select an option from among a list of
options that includes options of other services provided by the
intelligent display module 14. The list of options may include, for
example, an option 50 to perform vehicle diagnostic testing, an
option 52 to view engine codes, an option 54 to view transmission
codes, an option 56 to view ABS codes, an option 58 to view CTIS
codes, an 60 option to view and/or modify data in the vehicle
maintenance jacket, and an option 62 to view information stored in
a data logger. Given that the display 19 is a four line display in
the preferred embodiment, a vertically sliding winding 64 is used
to scroll through the options, and the user presses a select button
on the keypad 20 when a cursor 66 is positioned on the desired
option. As previously noted, other options may also be
provided.
[0040] Referring now to FIG. 4, a flow chart showing the operation
of the diagnostic system of FIGS. 1-2 to perform a diagnostic test
is illustrated. In connection with military vehicles, the
diagnostic system 12 may for example be made capable of performing
the following diagnostic tests, all of which provide information
pertaining to the health and operation of the tested subsystem:
[0041] [0041]
1 Test Exemplary Description and Measurement Test Application
Range(s) ENGINE TESTS Engine RPM (AVE) Measures average speed of
50-5000 RPM engine crankshaft. Engine RPM, Measures cranking RPM.
50-1500 RPM Cranking SI only Performed with ignition ON. Inhibit
spark plug firing allowing cranking without starting. Power Test
Measures engine's power 500-3500 RPM/s (RPM/SEC) producing
potential in units of RPM/SEC. Used when programmed engine
constants and corresponding Vehicle Identification Number (VID)
have not been established. Power Test (% Measures percentage of
0-100% Power) engine's power producing potential compared to full
power of a new engine. Compression Evaluates relative cylinder
0-90% Unbalance (%) compression and displays percent difference
between the highest and the lowest compression values in an engine
cycle. IGNITION TESTS Dwell Angle (TDC) Measures number of 10-72 @
degrees that the points are 2000 RPM closed. Points Voltage
Measures voltage drop 0-2 VDC (VDC) across the points (points
positive to battery return). Coil Primary Measures voltage
available 0-32 VDC at the coil positive terminal of the operating
condition of the coil. FUEL/AIR SYSTEM TESTS Fuel Supply Pressure
0-100 psi (psi) Fuel Supply Pressure This test measures the 0-10
psi (psi) outlet pressure of the fuel 0-30 psi pump. 0-100 psi
0-300 psi Fuel Return Pressure Measures return pressure to 0-100
psi (psi) detect return line blockage, leaks, or insufficient
restrictor back pressure. Fuel Filter Pressure Detects clogging via
PASS/FAIL Drop (PASS/FAIL) opening of a differential pressure
switch across the secondary fuel filter. Fuel Solenoid Measures the
voltage 0-32 VDC Voltage (VDC) present at the fuel shutoff solenoid
positive terminal. Air Cleaner Pressure Measures suction vacuum in
0-60 in. H.sub.2O Drop (RIGHT) (In air intake after the air
H.sub.2O) cleaner relative to ambient air pressure to detect extent
of air cleaner clogging. Air Cleaner Pressure Second air cleaner on
dual 0-60 in. H.sub.2O Drop (LEFT) (In H.sub.2O) intake systems.
Turbocharger Outlet Measures discharge 0-50 in. Hg Pressure (RIGHT)
(In pressure of the Hg) turbocharger. Turbocharger Outlet Second
turbocharger on 0-50 in. Hg Pressure (LEFT) (In dual intake
systems. Hg) Airbox Pressure Measures the airbox 0-20 in. Hg (In
Hg) pressure of two stroke 0-50 in. Hg engines. This measurement is
useful in detecting air induction path obstructions or leaks.
Intake Manifold Spark ignition engine intake 0-30 in. Hg Vacuum (In
Hg) system evaluation. Intake Manifold Spark ignition engine intake
0-30 in. Hg Vacuum Variation system evaluation. (In Hg)
LUBRICATION/COOLING SYSTEM TESTS Engine Oil Pressure Measures
engine oil 0-100 psi (psi) pressure. Engine Oil Filter Measures the
pressure drop 0-25 psi across the engine oil filter as indicator of
filter element clogging. Engine Oil Primarily applicable to air
120-300.degree. F. Temperature (.degree. F.) cooled engines.
Requires transducer output shorting switch on vehicle to perform
system zero offset test. Engine Coolant Transducer output shorting
120-300.degree. F. Temperature (.degree. F.) switch on vehicle
required. STARTING/CHARGING SYSTEM TESTS Battery Voltage Measure
battery voltage at 0-32 VDC (VDC) or near battery terminals.
Starter Motor Measures the voltage 0-32 VDC Voltage (VDC) present
at the starter motor positive terminal. Starter Negative Measures
voltage drop on 0-2 VDC Cable Voltage Drop starter path. A high
voltage (VDC) indicates excessive ground path resistance. Starter
Solenoid Measures voltage present at 0-32 VDC Volts (VDC) the
starter solenoid's positive terminal. Measures current through
battery ground path shunt. Starter Current, Measures starter
current. 0-1000 A Average (amps) 0-2000 A Starter Current First
Provides a good overall 0-1000 A Peak (Peak Amps, assessment of
complete 0-2000 A DC) starting system. Tests condition of the
starting circuit and battery's ability to deliver starting current.
The measurement is made at the moment the starter is engaged and
prior to armature movement. Peak currents less than nominal
indicate relatively high resistance caused by poor connections,
faulty wiring, or low battery voltage. Battery Internal Evaluate
battery condition 0-999.9 mohm Resistance by measuring battery
(Milliohms) voltage and current simultaneously. Starter Circuit
Measures the combined 0-999.9 mohm Resistance resistance of the
starter (Milliohms) circuit internal to the batteries. Battery
Resistance Measures rate of change of 0-999.9 mohm/s Change battery
resistance as an (Milliohms/sec) indicator of battery condition.
Battery Current Measures current to or from -999-1000 A the
battery. -999-2000 A Battery Electrolyte Determines whether
PASS/FAIL Level (PASS/FAIL) electrolyte in the sensed cell is of
sufficient level (i.e., in contact with electrolyte probe).
Alternator/Generator Measures output voltage of 0-32 VDC Output
Voltage generator/alternator. (VDC) Alternator/ Measures voltage
present at 0-32 VDC Generator Field alternator/generator field
Voltage (VDC) windings. Alternator/ Measures voltage drop in 0-2
VDC Generator Negative ground cable and Cable Voltage Drop
connection between (VDC) alternator/generator ground terminal and
battery negative terminal. Alternator Output Measures voltage
output at 0-3 VAC Current Sense the current transformer in
(VAC-RMS) 650 ampere alternator. Alternator AC Measures alternator
output 0-22 VAC Voltage Sense voltage. (VAC-RMS)
[0042] In general, the specific diagnostic tests that are performed
will be selected depending on the application, including the type
of equipment utilized by the vehicle 10. Most or all tests may be
simple in nature from a data acquisition standpoint, involving
primarily bringing the vehicle to a particular operating condition
(e.g., engine speed), if necessary, and obtaining information from
a suitable transducer constructed and placed to measure the
parameter of interest, although more elaborate tests could also be
utilized. Any number of different vehicle parameters can be
measured, each providing a separate data point regarding the
operational health of the vehicle. By providing an operator with
enough data points regarding the operational health of the vehicle,
the operator can use this information in a known way to determine
whether the vehicle is in good working order, or whether some
subsystem or component thereof needs to be repaired or
replaced.
[0043] At step 102, once the vehicle diagnostic option is selected,
the display 19 displays a menu of various tests that are available
to the operator, and the operator is prompted to select a test from
the test menu. Again, the list of options may comprise dozens of
options, such as some or all of those listed above, and/or tests
other than those listed above, and the operator can scroll through
the menu and selected the desired option.
[0044] At Step 104, the operator is prompted to perform a vehicle
related action. This step, which may or may not be necessary
depending on the type of test performed, may be used to prompt the
operator to start the engine to develop fuel pressure, oil
pressure, and so on, depending on which vehicle parameter is
tested. For example, if it is desired to test the operational
health of the battery, then the operator may be prompted to engage
the starter for a predetermined amount of time to establish a
current draw on the battery.
[0045] At Step 106, the intelligent display module 14 issues a
request for information from the test interface module 21and/or
from one or more of the control systems 24-30. As previously noted,
the test interface module 21 does not continually broadcast
information on the network communication link 32, because the
sensors 22 connected to the test interface module are used only for
diagnostic testing and because presumably diagnostic testing will
be performed only infrequently. Therefore, when the intelligent
display module 14 needs information from one of the sensors 22
pursuant to a test requested to be performed by the operator at the
operator interface 18, the intelligent display module 14 requests
the test interface module 21 for this information.
[0046] Alternatively, the needed information may be of a type that
is available from one of the control systems 24-30. The control
systems 24-30 are not only able to acquire information from sensors
located within the systems 34-40, but are also able to maintain
information derived from sensors located within the systems 34-40.
For example, the engine control system 30 may maintain information
pertaining to the average RPM of the engine, which is a parameter
that is not directly measurable but that can be easily calculated
based on parameters that are directly measurable. Through the
network communication link 32, all of this information is made
available to the diagnostic system 12. When the intelligent display
module 14 needs information from one of the control systems 24-30
pursuant to a test requested to be performed by the operator at the
operator interface 18, the intelligent display module 14 requests
the respective control system for this information.
[0047] At Step 108, the requested information is retrieved from one
of the sensors 22 by the test interface module 21, or from memory
or an internal sensor by the respective control system 24-30. At
step 110, the information is transmitted from the test interface
module 21 or from one of the control systems 24-30 to the
intelligent display module 14 by way of the network communication
link 32.
[0048] At step 112, the input status information is processed at
the intelligent display module 14. For example, if fuel supply
pressure is measured by one of the sensors 22, then the measured
fuel supply pressure may be compared with upper and lower benchmark
values to determine whether the fuel pressure is at an acceptable
level, or whether it is too high or too low. Finally, at step 114,
the results of the test are displayed to the operator.
[0049] As has been previously noted, in addition to performing
diagnostic tests, the intelligent display module 14 can also be
used to provide other services to an operator. For example, the
intelligent display module 14 can be used to allow the operator to
view engine codes, to view transmission codes, to view ABS codes,
and to view CTIS codes. In practice, these services can be
implemented simply by allowing acquiring the respective codes from
the respective control system 24-30, and displaying the codes to
the operator. Additionally, the control systems 24-30 may
automatically transmit fault information on the network
communication link 32, and the intelligent display module 14 can
listen for such fault information and display the fault information
to the user when it appears on the network communication link
32.
[0050] The intelligent display module 14 also includes sufficient
memory to allow maintenance information to be stored therein to
implement maintenance jacket functionality. The maintenance log may
consist of a table comprising a variety of fields, such as
registration numbers, chassis serial number, vehicle codes, and
dates and descriptions of maintenance actions performed. This
information may be retrieved and manipulated utilizing the computer
34 when the vehicle 10 is taken to a maintenance depot. If the
computer 34 is provided with an interactive electronic technical
manual (IETM) for the vehicle 10, this allows the IETM to have
access to all of the diagnostic data acquired by the intelligent
display module 14 as well as all of the maintenance data stored by
the intelligent display module 14. This greatly enhances the
ability to perform vehicle maintenance and diagnostics on the
vehicle 10.
[0051] Additionally, sufficient memory capacity is preferably
provided so that status information from the test interface module
21 as well as the control systems 24-30 can be sampled and stored
at frequent, regular intervals in a circular data queue (i.e., with
new data eventually replacing old data in the circular queue). This
allows the intelligent display module 14 to provide a data logger
service so that input data acquired over a period of time can be
viewed to allow an assessment of dynamic conditions leading to a
fault to be evaluated. Additionally, the vehicle is preferably
provided with one more sensors that indicate whether a severe
malfunction (e.g., the vehicle being involved in an accident) has
occurred. When inputs from these sensors indicates that a severe
malfunction has occurred, data logging is stopped, so that data
leading up to the severe malfunction is stored in a manner similar
to a so-called "black box recorder."
[0052] Referring now to FIG. 5, a schematic view of another type of
equipment service vehicle 110 that utilizes the diagnostic system
12 of FIGS. 1-4 is shown. The equipment service vehicle 110 is a
firefighting vehicle and comprises a water dispensing system 115
including water hoses, pumps, control valves, and so on, used to
direct water at the scene of a fire. The firefighting vehicle 110
may also comprise a foam dispensing system 118 as an alternative
fire extinguishing system. The firefighting vehicle 110 also
comprises emergency lighting 124, which may in practice be red and
white or red, white and blue flashing lights, as well as an
emergency horn 126 and an emergency siren 128 used, among other
things, for alerting motorists to the presence of the firefighting
vehicle 110 in transit to or at the scene of a fire. The
firefighting vehicle 110 may also comprise an extendable aerial 131
that supports a basket 132 used to vertically carry firefighting
personnel to an emergency situation at the scene of a fire. The
diagnostic system 12 may be used to diagnose vehicle malfunctions
in the manner described above in connection with the vehicle 10, as
well as to diagnose malfunctions of the specialized systems
described above found on firefighting vehicles.
[0053] Referring now to FIG. 6, a schematic view of another type of
equipment service vehicle 210 that utilizes the diagnostic system
12 of FIGS. 1-4 is shown. The equipment service vehicle 210 is a
mixing vehicle such as a cement mixing vehicle. The mixing vehicle
210 comprises a rotatable mixing drum 215 that is driven by engine
power from the engine 40 via a power takeoff mechanism 220.
Rotation of the mixing drum 215 is controlled under operator
control using a control system 225. The mixing vehicle 210 also
includes a dispenser 230 that dispenses the mixed matter or
material, for example, mixed cement. The diagnostic system 12 may
be used to diagnose vehicle malfunctions in the manner described
above in connection with the vehicle 10, as well as to diagnose
malfunctions of the specialized systems described above found on
mixing vehicles.
[0054] Referring now to FIG. 7, a schematic view of another type of
equipment service vehicle 310 that utilizes the diagnostic system
12 of FIGS. 1-4 is shown. The equipment service vehicle 310 is a
refuse handling vehicle and comprises one or more refuse
compartments 315 for storing collected refuse and other materials
such as goods for recycling. The refuse handling vehicle 310 also
includes a hydraulic compactor 317 for compacting collected refuse.
The hydraulic compactor 317 is driven by engine power from the
engine 40 via a power takeoff mechanism 320. The refuse handling
vehicle may also include an automatic loading or tipping system 325
for loading large refuse containers and for transferring the
contents of the refuse containers into one of the compartments 315.
The loading system 325 as well as the hydraulic compactor may
controlled under operator control using a control system 330. The
diagnostic system 12 may be used to diagnose vehicle malfunctions
in the manner described above in connection with the vehicle 10, as
well as to diagnose malfunctions of the specialized systems
described above found on refuse handling vehicles.
[0055] Referring now to FIG. 8, a schematic view of another type of
equipment service vehicle 410 that utilizes the diagnostic system
12 of FIGS. 1-4 is shown. The equipment service vehicle 410 is a
snow removal vehicle and comprises a snow removal device 415 which
may, for example, be a rotary blower, plow, or sweeper. The snow
removal device 415 may be driven by engine power from the engine 40
via a power takeoff mechanism 420 to remove snow from a region near
the snow removal vehicle 410 as the snow removal vehicle 410 is
moving. The diagnostic system 12 may be used to diagnose vehicle
malfunctions in the manner described above in connection with the
vehicle 10, as well as to diagnose malfunctions of the specialized
systems described above found on snow removal vehicles.
[0056] Advantageously, due to the utilization of a network
architecture in the preferred embodiment, the diagnostic system is
able to use sensors and other sources of information that are
already provided on the vehicle, because it is able to interact
with other vehicle control systems such as the engine control
system, the anti-lock brake control system, the central tire
inflation control system, and so on, via a network communication
link. The fact that the diagnostic system is connected to these
other systems, which are all typically capable of providing a vast
array of status information, puts this status information at the
disposal of the diagnostic system.
[0057] Further, due to the utilization of an intelligent display
module in the preferred embodiment, it is possible for the
intelligent display module to be connected to the network
communication link and collect information as necessary for a
variety of purposes. Thus, the preferred intelligent display module
is microprocessor-based and is capable of executing firmware to
provide additional functionality such as data logging, accident
reconstruction, and a vehicle maintenance record. Again, this
functionality can be achieved by taking advantage of the
information available from the vehicle subsystems by way of the
network architecture.
[0058] Moreover, by mounting the intelligent display module on
board the vehicle in the preferred embodiment, for example, in an
operator compartment, it is not necessary to bring the vehicle to a
maintenance depot to have vehicle malfunctions diagnosed. The
services offered by the intelligent display module are available
wherever and whenever the vehicle is in operation.
[0059] Many other changes and modifications may be made to the
present invention without department from the spirit thereof. The
scope of these and other changes will become apparent from the
appended claims.
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