U.S. patent application number 17/217409 was filed with the patent office on 2022-05-12 for leak check strategies avoiding high vapor generation conditions.
The applicant listed for this patent is DENSO CORPORATION, DENSO International America, Inc.. Invention is credited to Ashley JUSTMAN, Brandon MACLENNAN, Benjamin PALMER, Kyle RENNO.
Application Number | 20220146357 17/217409 |
Document ID | / |
Family ID | 1000005550651 |
Filed Date | 2022-05-12 |
United States Patent
Application |
20220146357 |
Kind Code |
A1 |
MACLENNAN; Brandon ; et
al. |
May 12, 2022 |
Leak Check Strategies Avoiding High Vapor Generation Conditions
Abstract
A control system for a vehicle includes a controller. The
controller is configured to receive signals from a plurality of
vehicle sensors, a vehicle communications system, a ride-share
application, a navigation system, or a combination of these. The
controller is configured to determine whether at least one of a
plurality of conditions is met to execute a small leak test on a
fuel system of the vehicle based on the signals, where the
plurality of conditions include an available time segment to
execute the small leak test, a level surface, a smooth surface, and
a constant vehicular momentum. The controller is configured to
execute the small leak test when at least one of the plurality of
conditions is met.
Inventors: |
MACLENNAN; Brandon;
(Southfield, MI) ; PALMER; Benjamin; (Southfield,
MI) ; RENNO; Kyle; (New Baltimore, MI) ;
JUSTMAN; Ashley; (Utica, MI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
DENSO International America, Inc.
DENSO CORPORATION |
Southfield
Kariya-city |
MI |
US
JP |
|
|
Family ID: |
1000005550651 |
Appl. No.: |
17/217409 |
Filed: |
March 30, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
63111780 |
Nov 10, 2020 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F02D 2041/225 20130101;
F02D 41/22 20130101; G01C 21/3438 20130101; G01M 3/025
20130101 |
International
Class: |
G01M 3/02 20060101
G01M003/02; G01C 21/34 20060101 G01C021/34; F02D 41/22 20060101
F02D041/22 |
Claims
1. A control system for a vehicle, the control system comprising: a
controller configured to receive output signals from a plurality of
vehicle sensors, a vehicle communications system, a ride-share
application, a navigation system, or a combination of these, the
controller being configured to determine whether at least one of a
plurality of conditions is met to execute a small leak test on a
fuel system of the vehicle based on the signals, the plurality of
conditions including an available time segment to execute the small
leak test, a level surface, a smooth surface, and a constant
vehicular momentum, wherein the controller is configured to execute
the small leak test when the at least one of the plurality of
conditions is met, wherein the controller is configured to receive
the output signals from the plurality of vehicle sensors and
determine whether the vehicle is level; and wherein if the vehicle
is not level, the controller is configured to determine a new
location that meets a predetermined location condition based on
signals from the navigation system, the controller is configured to
either control operation of the vehicle to drive the vehicle to the
new location or send a communication to a vehicle operator to drive
the vehicle to the new location, and the controller is configured
to execute the small leak test when the vehicle is at the new
location.
2. (canceled)
3. (canceled)
4. The control system of claim 1, wherein the controller is
configured to receive the output signals from a vehicle
communication sensor and determine whether a stop time of the
vehicle exceeds a predetermined time threshold.
5. The control system of claim 4, wherein, when the stop time of
the vehicle exceeds the predetermined time threshold, the
controller is configured to execute the small leak test.
6. The control system of claim 4, wherein the output signals from
the vehicle communication sensor indicate communication with a
traffic light, a train stop, or a combination of these.
7. The control system of claim 4, wherein the output signals from
the vehicle communication sensor indicate communication with an
infrastructure, a network, a remote vehicle, or a combination of
these.
8. The control system of claim 1, wherein the controller is
configured to receive the output signals from the ride-share
application and determine whether a stop time of the vehicle
exceeds a predetermined time threshold.
9. The control system of claim 8, wherein, when the stop time of
the vehicle exceeds the predetermined time threshold, the
controller is configured to execute the small leak test.
10. The control system of claim 8, wherein, the output signals from
the ride-share application indicate a pickup time and pickup
location for a fare.
11. The control system of claim 10, wherein, when the stop time of
the vehicle does not exceed the predetermined time threshold, the
controller is configured to send a signal to the ride-share
application indicating an extension for the pickup time.
12. A method for controlling a vehicle, the method comprising:
receiving, by a controller, output signals from a plurality of
vehicle sensors, a vehicle communications system, a ride-share
application, a navigation system, or a combination of these;
determining, by the controller, whether at least one of a plurality
of conditions are met to execute a small leak test on a fuel system
of the vehicle based on the output signals, the plurality of
conditions including an available time segment to execute the small
leak test, a level surface, a smooth surface, and a constant
vehicular momentum; executing, by the controller, the small leak
test based on the at least one of the plurality of conditions being
met to execute the small leak test; determining by the controller
whether the vehicle is level based on receiving output signals from
the plurality of vehicle sensors; determining by the controller, a
new location meeting a predetermined location condition based on
signals from the navigation system; either controlling by the
controller, operation of the vehicle to drive the vehicle to the
new location or sending by the controller, a communication to a
vehicle operator to drive the vehicle to the new location; and
executing, by the controller, the small leak test when the vehicle
is at the new location.
13. (canceled)
14. (canceled)
15. The method of claim 12 further comprising: determining, by the
controller, whether a stop time of the vehicle exceeds a
predetermined time threshold based on output signals from a vehicle
communication sensor.
16. The method of claim 15, further comprising: executing, by the
controller, the small leak test when the stop time of the vehicle
exceeds the predetermined time threshold.
17. The method of claim 15, wherein the output signals from the
vehicle communication sensor indicate communication with a traffic
light, a train stop, an infrastructure, a network, a remote
vehicle, or a combination of these.
18. The method of claim 12, further comprising: determining, by the
controller, whether a stop time of the vehicle exceeds a
predetermined time threshold based on output signals from the
ride-share application; and executing, by the controller, the small
leak test when the stop time of the vehicle exceeds the
predetermined time threshold.
19. The method of claim 18, wherein the output signals from the
ride-share application indicate a pickup time and pickup location
for a fare.
20. The method of claim 19, further comprising: sending, by the
controller, a signal to the ride-share application indicating an
extension for the pickup time when the stop time of the vehicle
does not exceed the predetermined time threshold.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application No. 63/111,780, filed on Nov. 10, 2020. The entire
disclosure of the above application is incorporated herein by
reference.
FIELD
[0002] The present disclosure relates to leak check strategies for
automobile fuel systems, and, more specifically, to leak check
strategies avoiding high vapor generation conditions.
BACKGROUND
[0003] This section provides background information related to the
present disclosure which is not necessarily prior art.
[0004] Automotive vehicles include evaporative emission control
(EVAP) systems. The EVAP system manages fuel vapor and must be
checked for fuel vapor leaks. The federal standard prohibits leaks
equivalent to a 0.020 inch diameter hole or larger. The
requirements for running the EVAP monitor may vary depending on the
vehicle. Generally speaking, the fuel tank must be 1/2/3/4 full,
the ambient outside temperature must not be too hot or too cold
(for example greater than 95.degree. F. or less than 30.degree.
F.), the vehicle must have met engine cold start conditions (for
example, sat overnight or for at least 8 hours without being
driven; engine coolant temperature is less than or equal to
12.degree. F. higher than ambient temperature, etc.), the vehicle
must have been driven for a minimum number of minutes (for example
10 minutes) within a speed range (for example 45-65 mph), the
components in the EVAP control system must be functioning normally,
and there must not be any fault codes.
[0005] New challenges have arisen for performing leak checks on
vehicles when an engine-off time is limited, such as in autonomous
vehicles and ride-share vehicles. Performing small leak checks
require a very stable system and usually a long amount of time
after the engine turns off to reach system stability. This presents
a significant challenge for autonomous and ride-share vehicles that
may not have enough engine-off time to complete the small leak
check.
SUMMARY
[0006] This section provides a general summary of the disclosure,
and is not a comprehensive disclosure of its full scope or all of
its features.
[0007] A control system for a vehicle includes a controller. The
controller is configured to receive signals from a plurality of
vehicle sensors, a vehicle communications system, a ride-share
application, a navigation system, or a combination of these. The
controller is configured to determine whether at least one of a
plurality of conditions is met to execute a small leak test on a
fuel system of the vehicle based on the signals, where the
plurality of conditions include an available time segment to
execute the small leak test, a level surface, a smooth surface, and
a constant vehicular momentum. The controller is configured to
execute the small leak test when at least one of the plurality of
conditions is met.
[0008] The controller may be configured to receive the output
signals from the plurality of vehicle sensors and determine whether
the vehicle is level.
[0009] The controller may be configured to determine a new location
that meets a predetermined location condition based on signals from
the navigation system when the vehicle is not level and to either
control operation of the vehicle to drive the vehicle to the new
location or send a communication to a vehicle operator to drive the
vehicle to the new location. The controller may be configured to
execute the small leak test when the vehicle is at the new
location.
[0010] The controller may be configured to receive the output
signals from the vehicle communication sensor and determine whether
a stop time of the vehicle exceeds a predetermined time
threshold.
[0011] The controller may be configured to execute the small leak
test when the stop time of the vehicle exceeds the predetermined
time threshold.
[0012] The output signals from the vehicle communication sensor may
indicate communication with a traffic light, a train stop, or a
combination of these.
[0013] The output signals from the vehicle communication sensor may
indicate communication with an infrastructure, a network, a remote
vehicle, or a combination of these.
[0014] The controller may be configured to receive the output
signals from the ride-share application and determine whether a
stop time of the vehicle exceeds a predetermined time
threshold.
[0015] The controller may be configured to execute the small leak
test when the stop time of the vehicle exceeds the predetermined
time threshold.
[0016] The output signals from the ride-share application may
indicate a pickup time and pickup location for a fare.
[0017] The controller may be configured to send a signal to the
ride-share application indicating an extension for the pickup time
when the stop time of the vehicle does not exceed the predetermined
time threshold.
[0018] An example method for controlling a vehicle according to the
present disclosure includes: receiving, by a controller, signals
from a plurality of vehicle sensors, a vehicle communications
system, a ride-share application, a navigation system, or a
combination of these; determining, by the controller, whether at
least one of a plurality of conditions are met to execute a small
leak test on a fuel system of the vehicle based on the signals the
plurality of conditions including an available time segment to
execute the small leak test, a level surface, a smooth surface, and
a constant vehicular momentum; and executing, by the controller,
the small leak test based on at least one of the plurality of
conditions being met to execute the small leak test.
[0019] The example method may include determining, by the
controller, whether the vehicle is level based on receiving the
output signals from the plurality of vehicle sensors.
[0020] The example method may include: determining, by the
controller, a new location meeting a predetermined location
condition based on signals from the navigation system; either
controlling, by the controller, operation of the vehicle to drive
the vehicle to the new location or sending, by the controller, a
communication to a vehicle operator to drive the vehicle to the new
location; and executing, by the controller, the small leak test
when the vehicle is at the new location.
[0021] The example method may include determining, by the
controller, whether a stop time of the vehicle exceeds a
predetermined time threshold based on the output signals from the
vehicle communication sensor.
[0022] The example method may include executing, by the controller,
the small leak test when the stop time of the vehicle exceeds the
predetermined time threshold.
[0023] The output signals from the vehicle communication sensor may
indicate communication with a traffic light, a train stop, an
infrastructure, a network, a remote vehicle, or a combination of
these.
[0024] The example method may include: determining, by the
controller, whether a stop time of the vehicle exceeds a
predetermined time threshold based on output signals from the
ride-share application; and executing, by the controller, the small
leak test when the stop time of the vehicle exceeds the
predetermined time threshold.
[0025] The output signals from the ride-share application may
indicate a pickup time and pickup location for a fare.
[0026] The example method may include sending, by the controller, a
signal to the ride-share application indicating an extension for
the pickup time when the stop time of the vehicle does not exceed
the predetermined time threshold.
[0027] Further areas of applicability will become apparent from the
description provided herein. The description and specific examples
in this summary are intended for purposes of illustration only and
are not intended to limit the scope of the present disclosure.
DRAWINGS
[0028] The drawings described herein are for illustrative purposes
only of selected embodiments and not all possible implementations,
and are not intended to limit the scope of the present
disclosure.
[0029] FIG. 1 is a schematic drawing of an example vehicle
according to the present disclosure.
[0030] FIG. 2 is a schematic drawing of an example control system
for the vehicle of FIG. 1.
[0031] FIG. 3 is a flowchart for an example method of controlling
the vehicle of FIG. 1.
[0032] FIG. 4 is a flowchart for another example method of
controlling the vehicle of FIG. 1.
[0033] FIG. 5 is a flowchart for another example method of
controlling the vehicle of FIG. 1.
[0034] FIG. 6 is a flowchart for another example method of
controlling the vehicle of FIG. 1.
[0035] Corresponding reference numerals indicate corresponding
parts throughout the several views of the drawings.
DETAILED DESCRIPTION
[0036] Example embodiments will now be described more fully with
reference to the accompanying drawings.
[0037] Example embodiments are provided so that this disclosure
will be thorough, and will fully convey the scope to those who are
skilled in the art. Numerous specific details are set forth such as
examples of specific components, devices, and methods, to provide a
thorough understanding of embodiments of the present disclosure. It
will be apparent to those skilled in the art that specific details
need not be employed, that example embodiments may be embodied in
many different forms and that neither should be construed to limit
the scope of the disclosure. In some example embodiments,
well-known processes, well-known device structures, and well-known
technologies are not described in detail.
[0038] The broad teachings of the disclosure can be implemented in
a variety of forms. Therefore, while this disclosure includes
particular examples, the true scope of the disclosure should not be
so limited since other modifications will become apparent upon a
study of the drawings, the specification, and the following claims.
In the written description and claims, one or more steps within a
method may be executed in a different order (or concurrently)
without altering the principles of the present disclosure.
Similarly, one or more instructions stored in a non-transitory
computer-readable medium may be executed in different order (or
concurrently) without altering the principles of the present
disclosure. Unless indicated otherwise, numbering or other labeling
of instructions or method steps is done for convenient reference,
not to indicate a fixed order.
[0039] Further, although each of the embodiments is described above
as having certain features, any one or more of those features
described with respect to any embodiment of the disclosure can be
implemented in and/or combined with features of any of the other
embodiments, even if that combination is not explicitly described.
In other words, the described embodiments are not mutually
exclusive, and permutations of one or more embodiments with one
another remain within the scope of this disclosure.
[0040] The terminology used herein is for the purpose of describing
particular example embodiments only and is not intended to be
limiting. As used herein, the singular forms "a," "an," and "the"
may be intended to include the plural forms as well, unless the
context clearly indicates otherwise. The terms "comprises,"
"comprising," "including," and "having," are inclusive and
therefore specify the presence of stated features, integers, steps,
operations, elements, and/or components, but do not preclude the
presence or addition of one or more other features, integers,
steps, operations, elements, components, and/or groups thereof. The
method steps, processes, and operations described herein are not to
be construed as necessarily requiring their performance in the
particular order discussed or illustrated, unless specifically
identified as an order of performance. It is also to be understood
that additional or alternative steps may be employed.
[0041] When an element or layer is referred to as being "on,"
"engaged to," "connected to," or "coupled to" another element or
layer, it may be directly on, engaged, connected or coupled to the
other element or layer, or intervening elements or layers may be
present. In contrast, when an element is referred to as being
"directly on," "directly engaged to," "directly connected to," or
"directly coupled to" another element or layer, there may be no
intervening elements or layers present. Other words used to
describe the relationship between elements should be interpreted in
a like fashion (e.g., "between" versus "directly between,"
"adjacent" versus "directly adjacent," etc.). As used herein, the
term "and/or" includes any and all combinations of one or more of
the associated listed items.
[0042] Although the terms first, second, third, etc. may be used
herein to describe various elements, components, regions, layers
and/or sections, these elements, components, regions, layers and/or
sections should not be limited by these terms. These terms may be
only used to distinguish one element, component, region, layer or
section from another region, layer or section. Terms such as
"first," "second," and other numerical terms when used herein do
not imply a sequence or order unless clearly indicated by the
context. Thus, a first element, component, region, layer or section
discussed below could be termed a second element, component,
region, layer or section without departing from the teachings of
the example embodiments.
[0043] Spatially relative terms, such as "inner," "outer,"
"beneath," "below," "lower," "above," "upper," and the like, may be
used herein for ease of description to describe one element or
feature's relationship to another element(s) or feature(s) as
illustrated in the figures. Spatially relative terms may be
intended to encompass different orientations of the device in use
or operation in addition to the orientation depicted in the
figures. For example, if the device in the figures is turned over,
elements described as "below" or "beneath" other elements or
features would then be oriented "above" the other elements or
features. Thus, the example term "below" can encompass both an
orientation of above and below. The device may be otherwise
oriented (rotated 90 degrees or at other orientations) and the
spatially relative descriptors used herein interpreted
accordingly.
[0044] Spatial and functional relationships between elements (for
example, between modules) are described using various terms,
including "connected," "engaged," "interfaced," and "coupled."
Unless explicitly described as being "direct," when a relationship
between first and second elements is described in the above
disclosure, that relationship encompasses a direct relationship
where no other intervening elements are present between the first
and second elements, and also an indirect relationship where one or
more intervening elements are present (either spatially or
functionally) between the first and second elements.
[0045] The phrase "at least one of A, B, and C" should be construed
to mean a logical (A OR B OR C), using a non-exclusive logical OR,
and should not be construed to mean "at least one of A, at least
one of B, and at least one of C." The term "set" does not
necessarily exclude the empty set. The term "non-empty set" may be
used to indicate exclusion of the empty set. The term "subset" does
not necessarily require a proper subset. In other words, a first
subset of a first set may be coextensive with (equal to) the first
set.
[0046] In the figures, the direction of an arrow, as indicated by
the arrowhead, generally demonstrates the flow of information (such
as data or instructions) that is of interest to the illustration.
For example, when element A and element B exchange a variety of
information but information transmitted from element A to element B
is relevant to the illustration, the arrow may point from element A
to element B. This unidirectional arrow does not imply that no
other information is transmitted from element B to element A.
Further, for information sent from element A to element B, element
B may send requests for, or receipt acknowledgements of, the
information to element A.
[0047] In this application, including the definitions below, the
term "module" or the term "controller" may be replaced with the
term "circuit." The term "module" may refer to, be part of, or
include processor hardware (shared, dedicated, or group) that
executes code and memory hardware (shared, dedicated, or group)
that stores code executed by the processor hardware.
[0048] The module may include one or more interface circuits. In
some examples, the interface circuit(s) may implement wired or
wireless interfaces that connect to a local area network (LAN) or a
wireless personal area network (WPAN). Examples of a LAN are
Institute of Electrical and Electronics Engineers (IEEE) Standard
802.11-2016 (also known as the WIFI wireless networking standard)
and IEEE Standard 802.3-2015 (also known as the ETHERNET wired
networking standard). Examples of a WPAN are IEEE Standard 802.15.4
(including the ZIGBEE standard from the ZigBee Alliance) and, from
the Bluetooth Special Interest Group (SIG), the BLUETOOTH wireless
networking standard (including Core Specification versions 3.0,
4.0, 4.1, 4.2, 5.0, and 5.1 from the Bluetooth SIG).
[0049] The module may communicate with other modules using the
interface circuit(s). Although the module may be depicted in the
present disclosure as logically communicating directly with other
modules, in various implementations the module may actually
communicate via a communications system. The communications system
includes physical and/or virtual networking equipment such as hubs,
switches, routers, and gateways. In some implementations, the
communications system connects to or traverses a wide area network
(WAN) such as the Internet. For example, the communications system
may include multiple LANs connected to each other over the Internet
or point-to-point leased lines using technologies including
Multiprotocol Label Switching (MPLS) and virtual private networks
(VPNs).
[0050] In various implementations, the functionality of the module
may be distributed among multiple modules that are connected via
the communications system. For example, multiple modules may
implement the same functionality distributed by a load balancing
system. In a further example, the functionality of the module may
be split between a server (also known as remote, or cloud) module
and a client (or, user) module. For example, the client module may
include a native or web application executing on a client device
and in network communication with the server module.
[0051] The term code, as used above, may include software,
firmware, and/or microcode, and may refer to programs, routines,
functions, classes, data structures, and/or objects. Shared
processor hardware encompasses a single microprocessor that
executes some or all code from multiple modules. Group processor
hardware encompasses a microprocessor that, in combination with
additional microprocessors, executes some or all code from one or
more modules. References to multiple microprocessors encompass
multiple microprocessors on discrete dies, multiple microprocessors
on a single die, multiple cores of a single microprocessor,
multiple threads of a single microprocessor, or a combination of
the above.
[0052] Shared memory hardware encompasses a single memory device
that stores some or all code from multiple modules. Group memory
hardware encompasses a memory device that, in combination with
other memory devices, stores some or all code from one or more
modules.
[0053] The term memory hardware is a subset of the term
computer-readable medium. The term computer-readable medium, as
used herein, does not encompass transitory electrical or
electromagnetic signals propagating through a medium (such as on a
carrier wave); the term computer-readable medium is therefore
considered tangible and non-transitory. Non-limiting examples of a
non-transitory computer-readable medium are nonvolatile memory
devices (such as a flash memory device, an erasable programmable
read-only memory device, or a mask read-only memory device),
volatile memory devices (such as a static random access memory
device or a dynamic random access memory device), magnetic storage
media (such as an analog or digital magnetic tape or a hard disk
drive), and optical storage media (such as a CD, a DVD, or a
Blu-ray Disc).
[0054] The apparatuses and methods described in this application
may be partially or fully implemented by a special purpose computer
created by configuring a general purpose computer to execute one or
more particular functions embodied in computer programs. Such
apparatuses and methods may be described as computerized
apparatuses and computerized methods. The functional blocks and
flowchart elements described above serve as software
specifications, which can be translated into the computer programs
by the routine work of a skilled technician or programmer.
[0055] The computer programs include processor-executable
instructions that are stored on at least one non-transitory
computer-readable medium. The computer programs may also include or
rely on stored data. The computer programs may encompass a basic
input/output system (BIOS) that interacts with hardware of the
special purpose computer, device drivers that interact with
particular devices of the special purpose computer, one or more
operating systems, user applications, background services,
background applications, etc.
[0056] The computer programs may include: (i) descriptive text to
be parsed, such as HTML (hypertext markup language), XML
(extensible markup language), or JSON (JavaScript Object Notation),
(ii) assembly code, (iii) object code generated from source code by
a compiler, (iv) source code for execution by an interpreter, (v)
source code for compilation and execution by a just-in-time
compiler, etc. As examples only, source code may be written using
syntax from languages including C, C++, C#, Objective C, Swift,
Haskell, Go, SQL, R, Lisp, Java.RTM., Fortran, Perl, Pascal, Curl,
OCaml, JavaScript.RTM., HTML5 (Hypertext Markup Language 5th
revision), Ada, ASP (Active Server Pages), PHP (PHP: Hypertext
Preprocessor), Scala, Eiffel, Smalltalk, Erlang, Ruby, Flash.RTM.,
Visual Basic.RTM., Lua, MATLAB, SIMULINK, and Python.RTM..
[0057] As people become more environmentally conscious, and
automobiles become more advanced, ride-sharing between people,
particularly using autonomous vehicles, has become more common. The
ride-share vehicles often run non-stop or only have short stops
throughout the day before receiving new ride requests. The lack of
stops or short stops do not provide adequate time for vehicle
systems, such as the evaporative emission control (EVAP) system, to
run federally required tests.
[0058] The EVAP system and/or the EVAP system in conjunction with a
Powertrain Control Module (PCM) tests the integrity of the fuel
system and its ability to draw fuel vapor into the engine for
combustion. Particularly, a leak portion of the test may check for
fuel vapor leaks, and, more specifically, for leakage rates
equivalent to a 0.020 inch diameter hole or greater (i.e., small
leak check). The leak detection test may be activated under a
specific set of engine and vehicle operating conditions. For
example, the components in the EVAP control system must be
functioning normally and there must not be any fault codes for the
leak detection test to be activated. Additionally, one or more of
the following vehicle operating conditions may also need to be met:
the fuel tank must be 1/2/3/4 full, the ambient outside temperature
must not be too hot or too cold (for example greater than
95.degree. F. or less than 30.degree. F.), the vehicle must meet
engine cold start conditions (for example, sat overnight or for at
least 8 hours without being driven; engine coolant temperature is
less than or equal to 12.degree. F. higher than ambient
temperature, etc.), the vehicle must have been started and driven
for a minimum number of minutes (for example 10 minutes) within a
speed range (for example 45-65 mph), the vehicle must perform an
extended idle during the drive cycle (for example, idle for 30
seconds), and the vehicle must be shut down for a minimum number of
minutes after the cold start and drive.
[0059] Fuel system leak checks in automobiles have continuously
evolved as new challenges arise. One of the more recent challenges
is performing 0.020 inch leak checks (i.e., small leak checks) on
vehicles when engine-off time is limited with the evolution of
autonomous vehicles and ride-share. Performing small leak checks
requires a very stable system and usually a long amount of time
after the engine turns off to reach system stability. This presents
a significant challenge for autonomous and ride-share vehicles that
may not have enough engine-off time to complete the small leak
checks. With special vehicle control and leak check timing the
vehicle may be provided the right opportunities to complete leak
checks. For example, a vehicle may be programmed to drive to an
undisturbed location for a predetermined time to complete a leak
check. Alternatively, when the vehicle is stopped for a certain
amount of time, a leak check may be programmed to start.
[0060] The control system of the present disclosure may implement
one or more alternative methods to create a stable environment,
which avoids high vapor generation from fuel movement, to run small
leak checks with limited engine-off time, particularly applicable
in autonomous vehicles and ride-sharing. For example, the vehicle
may be programmed or controlled to drive to an undisturbed location
and execute a leak check by any means, including turning the engine
off to complete the leak check.
[0061] Alternatively a vehicle may communicate with an
infrastructure in a traffic light, train stop, or other stop
location. If the vehicle receives information that the car may be
resting equal to or greater than a predetermined amount of time, a
leak check may be executed by any means, including turning the
engine off to complete the leak check.
[0062] Alternatively a vehicle may communicate with other road
infrastructure, for example on a highway, to understand upcoming
road conditions that may cause vehicular momentum adjustment,
including traffic, potholes, turns in highway, cruise control, etc.
The vehicle may use a predetermined momentum change threshold to
judge if there will be too much momentum change, generating fuel
slosh and thus vapor generation. If conditions are met, a leak
check may be executed by any means, including turning the engine
off if there are electric motors available to maintain vehicle
speed.
[0063] The vehicle may communicate with application users to
understand location and determine if a leak check may be executed
by any means, including turning the engine off to complete the leak
check. For example, a vehicle may communicate via a ride-share
application to understand users distance from the vehicle and
determine if a leak check can be ran before the user arrives to the
vehicle. Alternatively, the vehicle may utilize application
communications to schedule a window of time to run the leak
check.
[0064] Where communications with other vehicles and/or
infrastructure are utilized, a dedicated short range communications
(DSRC) radio, a cellular-V2X (C-V2X) radio, or any other
communications radio, may communicate vehicle-to-vehicle (V2V),
vehicle-to-infrastructure (V2I), vehicle-to-pedestrian (V2P), or
vehicle-to-network (V2N), collectively referred to as
vehicle-to-everything (V2X).
[0065] Now, referring to FIG. 1, a vehicle 10, or host vehicle
(HV), may be equipped with one or more of a vehicle communications
system (for example only, a dedicated short range communication
(DSRC) system or a cellular-V2X (C-V2X) system) 14, a navigation
system 18, and a ride-share application 22. While the vehicle 10 is
described as being equipped with a DSRC system or a C-V2X system,
in other embodiments, the vehicle 10 may be equipped with any
vehicle communications system utilizing an antenna for transmitting
information. Through the DSRC or C-V2X system 20, the vehicle 10
may be capable of vehicle-to-vehicle (V2V),
vehicle-to-infrastructure (V2I), vehicle-to-pedestrian (V2P), and
vehicle-to-network (V2N), collectively referred to as
vehicle-to-everything (V2X), communications.
[0066] The vehicle 10 may be driven by an operator or may be an
autonomous vehicle. For purposes of this disclosure, in the case of
an autonomous vehicle, the autonomous vehicle is a vehicle that may
be operated by a control system of the vehicle, based on various
inputs supplied by a vehicle operator, a navigation system, a
vehicle communication system, vehicle sensors, etc., such as a
destination, a vehicle route, road conditions, traffic conditions,
a peripheral view, etc. For purposes of this disclosure, any known
autonomous vehicle control system is applicable, as the disclosure
is not focused on the autonomous control of the vehicle, and would
be applicable for any autonomously controlled vehicle.
[0067] The vehicle communications system 14 may be configured to
transmit and receive signals representing, for example, early
warnings of accidents and driving hazards to/from remote vehicles
that are also equipped with V2X systems and/or to/from an
infrastructure communication location equipped with a V2X system.
Additionally, the vehicle communications system 14 may be
configured to predict future accidents and driving hazards based on
communication with remote vehicles and/or infrastructure
communication locations that are also equipped with V2X systems by
calculating the current and future positions of the vehicle 10.
[0068] The vehicle communications system 14 may include an antenna
26 (for example only, a 5.9 GHz DSRC antenna, a 5G cellular
antenna, or any other communications antenna) which receives
information from Global Network Satellite Systems (GNSS) 30 and/or
Global Positioning Systems (GPS) 34, which communicate with the
vehicle communications system 14, along with Basic Safety Messages
(BSM) periodically transmitted by other vehicles, infrastructure,
pedestrians, networks, etc., containing the current position,
position accuracy, speed, heading, brake status, and other vehicle
infrastructure, pedestrian, network, etc., information. The SAE
J2735 document defines the BSMs that may be utilized and the
frequency and power with which the BSMs are transmitted. With V2X
technology, vehicles can have improved safety by knowing more about
the other surrounding vehicles, infrastructure, pedestrians,
etc.
[0069] The vehicle communications system 14 may communicate with
the other vehicles, infrastructure, pedestrians, networks, etc.,
equipped with a V2X system, for example, through the antenna 26 by
using, for example, a 75 MHz band around a 5.9 GHz signal. While a
75 MHz band around a 5.9 GHz signal is provided as an example
embodiment, it is understood that the vehicle communications system
14 may communicate with the other vehicles, pedestrians,
infrastructures, networks, etc., by any method including at signals
other than the 5.9 GHz signal, such as with a 5G cellular signal or
any other communications signal. The vehicle communications system
14 may operate in both line-of-sight (LOS) and non-line-of-sight
(NLOS) conditions, thereby allowing the vehicle communications
system 14 to receive communications from other vehicles and
infrastructures related to warnings and driving hazards, even with
blockage from intervening vehicles, blind corners, or other
roadside infrastructure.
[0070] All of the components of the vehicle communications system
14 may be located at one or multiple locations on the roof of the
vehicle. Alternatively, some of the components may be located in
the interior of the vehicle 10. While the vehicle communications
system 14 is illustrated as being located on the roof of the
vehicle 10, in some embodiments, the vehicle communications system
14, and any or all of its components, may be disposed at any
location on the vehicle 10 to include the front, rear, sides, and
internal to the vehicle 10.
[0071] The vehicle 10 may be an autonomous vehicle, a ride-share
vehicle, or a combination of these. The vehicle 10 may utilize the
navigation system 18 to understand vehicle routes and
infrastructure. The navigation system 18 may communicate with the
GPS 34 through the antenna 26 and utilize internally stored maps to
plot drive routes. The navigation system 18, the V2X
communications, or a combination of these, may provide information
regarding traffic delays, such as stop lights, train crossings,
accidents, road closures, heavy traffic, etc.
[0072] The vehicle 10 may utilize the ride-share application 22 for
scheduling rides. Users may request rides through the ride-share
application on their devices, and the ride-share application may
communicate the rides with the vehicle 10. The vehicle may have an
opportunity to accept or decline rides, or the vehicle may have the
opportunity to adjust a pick-up time for a ride. The ride-share
application 22 may additionally provide a schedule of rides,
pick-up locations and times, and drop-off locations and times for
the vehicle 10 during a predetermined time period (for example, 8
hours, 24 hours, 1 week, etc.).
[0073] The vehicle 10 may additionally include, among other
systems, an engine 38 and fuel system 42. The fuel system 42 may
provide fuel from a fuel tank 46 to the engine 38 for use in
propelling the vehicle 10. For example, the engine 38 may be an
internal combustion engine 38 that burns fuel from the fuel system
42 to propel the vehicle 10.
[0074] In addition to the fuel system 42, the vehicle 10 may
include an electric propulsion system 50 having a battery 54 that
provides electricity for propelling the vehicle 10. Under some
operating conditions, the electric propulsion system 50 may work
with the engine 38 to propel the vehicle 10.
[0075] The communication system 14, the navigation system 18, the
ride-share application 22, the engine 38, the fuel system 42, and
the electric propulsion system 50 may communicate with a controller
58. The controller 58 may evaluate system inputs and make
determinations for vehicle control based on the system inputs.
[0076] Referring to FIG. 2, a control system 62 for the vehicle 10
is illustrated. The controller 58 may be a control module or a
control circuit that receives various inputs, makes determinations
based on the inputs and/or stored data, and provides commands to
various systems and parts for controlling the vehicle 10. In this
application, the term "module" or "unit" may be replaced with the
term "circuit." The term "module" may refer to, be part of, or
include processor hardware (shared, dedicated, or group) that
executes code and memory hardware (shared, dedicated, or group)
that stores code executed by the processor hardware. The code is
configured to provide the features of the modules described herein.
The term memory hardware is a subset of the term computer-readable
medium. The term computer-readable medium, as used herein, does not
encompass transitory electrical or electromagnetic signals
propagating through a medium (such as on a carrier wave). The term
computer-readable medium is therefore considered tangible and
non-transitory. Non-limiting examples of a non-transitory
computer-readable medium are nonvolatile memory devices (such as a
flash memory device, an erasable programmable read-only memory
device, or a mask read-only memory device), volatile memory devices
(such as a static random access memory device or a dynamic random
access memory device), magnetic storage media (such as an analog or
digital magnetic tape or a hard disk drive), and optical storage
media (such as a CD, a DVD, or a Blu-ray Disc).
[0077] The controller 58 may include, among other modules, an
evaporative emission control (EVAP) module 66 and a powertrain
control module (PCM) 70. The EVAP module 66 may be in communication
with the PCM 70 to control, for example, the vehicle 10 and perform
a federally regulated leak test. The EVAP module 66 and PCM 70 may
test the integrity of the fuel system and its ability to draw fuel
vapor into the engine for combustion. Particularly, a leak
detection portion of the test may check for fuel vapor leaks, and,
for example, for leakage rates equivalent to a 0.020 inch diameter
hole or greater (i.e., small leak check). The leak detection test
may be activated under a specific set of engine and vehicle
operating conditions. For example, one or more of the following
conditions may be required: the components in the EVAP control
system must be functioning normally; there must not be any fault
codes; the fuel tank must be 1/2-3/4 full; the ambient outside
temperature must not be too hot or too cold (for example greater
than 95.degree. F. or less than 30.degree. F.); the vehicle must
meet engine cold start conditions (for example, sat overnight or
for at least 8 hours without being driven; engine coolant
temperature is less than or equal to 12.degree. F. higher than
ambient temperature, etc.); the vehicle must have been started and
driven for a minimum number of minutes (for example 10 minutes)
within a speed range (for example 45-65 mph); the vehicle must be
shut down for a minimum number of minutes after the cold start and
drive (for example, 45 minutes or more); the fuel system must be
stable (for example, no fuel slosh and no vapor generation); and
the vehicle must perform an extended idle during the drive cycle
(for example, idle for 30 seconds).
[0078] The controller 58 may be in communication with vehicle
sensors 74. For example, the controller 58 may receive output from
a vehicle speed sensor, temperature sensors, fuel pressure sensors,
other fuel system sensors, engine sensors, electric propulsion
system sensors, and other vehicle sensors. The controller 58 may
determine current vehicle conditions from the output of the vehicle
sensors 74. Additionally, or alternatively, the controller 58 may
determine control signals for the systems in the vehicle 10 based
on the output of the vehicle sensors 74.
[0079] For example, the EVAP module 66 may receive fuel tank fill
level, fault codes, ambient outside temperature, engine-off time,
engine drive time, vehicle speed, cold start condition, vapor
detection in the fuel tank, idle time, fuel pressure, etc., from
the vehicle sensors 74. The EVAP module 66 may use the inputs from
the vehicle sensors 74 to determine conditions for the small leak
fuel system test. For example, the EVAP module 66 may evaluate the
fuel tank fill level signal to determine if the fuel tank is filled
above a threshold (for example, within a range of 1/2 to 3/4
filled). The EVAP module 66 may evaluate the fault codes signal to
determine whether there are any fault codes. The EVAP module 66 may
evaluate the output of the ambient outside temperature sensor to
determine whether the ambient temperature is within a threshold
temperature range (for example, greater than 30.degree. F. and less
than 95.degree. F.). The EVAP module 66 may evaluate the engine-off
time signal and/or an output of a cold start condition sensor to
determine whether the vehicle 10 has been shut down for a threshold
number of hours (for example at least 8 hours) to trigger a cold
start condition and to determine whether the vehicle has been shut
down for a minimum number of minutes after the cold start and drive
(for example, 45 minutes or more). The EVAP module 66 may evaluate
the engine drive time signal to determine whether the vehicle has
been started and driven for a minimum number of minutes (for
example 10 minutes). The EVAP module 66 may evaluate the output of
the vehicle speed sensor to determine whether the vehicle speed is
within a speed range (for example 45-65 mph). The EVAP module 66
may evaluate an output of a fuel vapor signal in the fuel tank to
determine whether the fuel system is stable (for example, no fuel
slosh and no vapor generation). The EVAP module 66 may evaluate the
output of the vehicle speed sensor, the engine drive time signal,
and the gear selection signal to determine whether the vehicle has
completed an extended idle during the drive cycle (for example,
idle for 30 seconds).
[0080] The controller 58 may also, or alternatively, be in
communication with a V2X system 78. The V2X system 78 may send and
receive communications including vehicle-to-vehicle (V2V)
communications, vehicle-to-infrastructure (V2I) communications,
vehicle-to-pedestrian (V2P) communications, and vehicle-to-network
(V2N) communications, collectively referred to as
vehicle-to-everything (V2X) communications, for example through the
antenna 26. For example, the controller 58 may receive V2X
communications and may determine current vehicle driving conditions
from the output of the V2X system 78. Additionally, or
alternatively, the controller 58 may determine control signals for
the systems in the vehicle 10 based on the output of the V2X system
78.
[0081] For example, the EVAP module 66 may receive data for traffic
signals, train crossings, accidents, driving conditions, traffic
conditions, road conditions, or other conditions that may affect
vehicle driving or traffic from the V2X system 78. The EVAP module
66 may evaluate the output from the V2X system 78 and determine
whether traffic conditions or driving conditions allow for
completion of the small leak test. For example, if the EVAP module
66 receives a signal from the V2X system 78 indicating that the
vehicle 10 will be stopped at a train track or stopped at an
accident for a period of time longer than a threshold time, the
EVAP module 66 may indicate to the PCM 70 to run the small leak
test. Alternatively, or additionally, for example, if the EVAP
module 66 receives an output from the V2X system 78 that the road
is smooth and straight for a threshold number of miles (such that
there is not likely to be fuel slosh or vapor generation), and the
vehicle 10 includes the electric propulsion system 50, the EVAP
module 66 may indicate to the PCM 70 to electrically power the
vehicle 10, shut down the gas engine, and run the small leak
test.
[0082] The controller 58 may also, or alternatively, be in
communication with the ride-share application 22. The ride-share
application 22 may send and receive communications with a remote
system for scheduling and navigating ride-share fares. For example,
the controller 58 may receive ride-share application 22
communications and may determine whether there is time for a stop
to run the small leak test.
[0083] For example, the EVAP module 66 may receive communications
from the ride-share application 22 scheduling a new fare. The EVAP
module 66 may evaluate the timing of the new fare and determine if
it is greater than a time threshold. If so, the EVAP module 66 may
indicate to the PCM 70 to run the small leak test. The EVAP module
66 may receive communications from the ride-share application 22
providing a drop off location. The EVAP module 66 may work with the
navigation system 18 and the V2X communications 78 to determine
whether the vehicle 10 will be stopped or will be driving down a
smooth straight road for a threshold amount of time to complete the
small leak test. If so, the EVAP module 66 may indicate to the PCM
70 to run the small leak test.
[0084] The controller 58 may also, or alternatively, be in
communication with the navigation system 18. The navigation system
18 may send and receive communications with the GPS 34 or GNSS 30
for navigating. For example, the controller 58 may receive
navigation system 18 communications and may determine whether there
is time for a stop to run the small leak test, whether the road is
straight (to maintain consistent vehicular momentum and reduce fuel
slosh/vapor generation), whether there is a flat surface (as
opposed to inclined or declined) nearby to run the small leak test,
etc.
[0085] For example, the EVAP module 66 may receive communications
from the navigation system 18 indicating vehicle route, road
conditions, traffic conditions, etc. The EVAP module 66 may
evaluate the navigation system 18 communications to determine a
drop off time for a ride-share fare, whether the vehicle 10 will be
stopped for a threshold time, whether the vehicle 10 will be
navigating down a smooth, straight road for a threshold time, etc.
If the conditions are correct, the EVAP module 66 may indicate to
the PCM 70 to run the small leak test.
[0086] The controller 58 may additionally, or alternatively,
communicate with the engine 38, the fuel system 42, and the
electric propulsion system 50, among other systems and/or parts.
For example, the controller 58 may command the engine 38 to shut
down, start up, and or idle at a predetermined vehicle speed during
the small leak test. The controller 58 may command the fuel system
42 during the small leak test. The controller 58 may command the
electric propulsion system 50 to operate the vehicle 10 during the
small leak test 50.
[0087] For example, the PCM 70 may send signals controlling an
engine-off condition, an engine speed (rpm), an engine-on
condition, etc., to the engine 38. The PCM 70 may send signals
controlling an air-fuel-ratio, a fueling state, etc., to the fuel
system 42. The PCM 70 may send signals controlling the system-on
state, the system-off state, the drive state, the battery power
supply, the vehicle speed, etc., to the electric propulsion system
50.
[0088] Now referring to FIG. 3, an example method 100 for
performing a leak check is illustrated. Method 100 begins at 104.
At 104, the vehicle 10 is keyed-off. At 108, the vehicle 10 is
keyed-on. The vehicle 10 key-on may include turning the accessories
on in the vehicle or starting the engine.
[0089] At 112, the controller 58 determines whether the vehicle 10
meets the required leak check frequency. For example, the required
leak check frequency may be federally regulated, vehicle
manufacturer regulated, or a combination of these. For example, the
required leak check frequency may be 26% of qualifying trips (per
CARB OBD2 regulation).
[0090] If true at 112, method 100 may end at 116. If false at 112,
the method 100 determines whether the vehicle 10 meets the required
small leak test conditions at 118. For example, the conditions may
include: the fuel tank must be 1/2-3/4full, the ambient outside
temperature must not be too hot or too cold (for example greater
than 95.degree. F. or less than 30.degree. F.), the vehicle must
have met engine cold start conditions (for example, sat overnight
or for at least 8 hours without being driven; engine coolant
temperature is less than or equal to 12.degree. F. higher than
ambient temperature, etc.), the vehicle must have been driven for a
minimum number of minutes (for example 10 minutes) within a speed
range (for example 45-65 mph), the components in the EVAP control
system must be functioning normally, there must not be any fault
codes, or a combination thereof. If false, method 100 ends at
116.
[0091] If true at 118, method 100 may determine a vehicle location
at 120. For example, the controller 58 may communicate with the
navigation system 18 to determine the vehicle location. The
navigation system 18 may determine vehicle location from the GPS 34
or GNSS 30, for example.
[0092] At 124, method 100 may determine whether the vehicle 10 is
in a location suitable for a leak check. For example, the
controller 58 may communicate with the navigation system 18, the
vehicle sensor 74, the V2X communication system 78, or combination
of these, to determine whether the vehicle 10 meets a predetermined
environmental condition, such as whether the vehicle 10 is on a
level surface (as opposed to an incline or decline), is away from
other traffic and in a location to be parked, is in indirect
sunlight, is in a stable environmental condition, or any other
location conditions.
[0093] If true at 124, the method 100 may perform the leak check by
any suitable means at 128. For example, the controller 58 may shut
the engine 38 off for a predetermined time (such as 30 minutes or
more). The controller 58 may then restart the engine 38 and command
the engine 38 to idle at a predetermined speed (for example, within
a range of 400-800 RPM) for a predetermined idle time (for example,
10 minutes or more). During the engine idle time, the controller 58
may execute the small leak test.
[0094] For example, the small leak test may detect leaks by
pressurizing a fuel tank system. Alternatively, the small leak test
may detect leaks by applying a vacuum to the fuel tank system.
[0095] If false at 124, the method 100 may determine a new location
suitable for executing the small leak test at 132. For example, the
new location may meet the predetermined environmental condition,
such as be level (as opposed to on an incline or decline), be
suitable for parking (out of the flow of traffic), be in indirect
sunlight, be in a stable environmental condition, or any other
location conditions. The controller 58 may communicate with the
navigation system 18 and the V2X communication system 78 to
determine the new location. For example, the navigation system 18
may provide the vehicle location. The V2X communication system 78
may ping infrastructure within a radius (for example within a
five-mile radius) for a location meeting the predetermined
environmental condition, such as a level surface, outside of the
flow of traffic, in indirect sunlight, in a stable environmental
condition, or any other location conditions.
[0096] At 136, the vehicle 10 is keyed-on and/or driven to the new
location. For example, the controller 58 may provide coordinates to
the navigation system 18 for display to a vehicle operator. In
autonomous vehicles, the controller 58 may communicate with the
navigation system 18 and the vehicle control to autonomously drive
the vehicle 10 to the new location.
[0097] At 128, the leak check may be performed. For example, the
controller 58 may execute the small leak test, as previously
described.
[0098] Method 100 Ends at 116.
[0099] Now referring to FIG. 4, an alternative example method 200
for performing a leak check is illustrated. Method 200 begins at
204. At 204, the vehicle 10 is running but stopped (for example at
a traffic light, train stop, traffic accident, traffic jam, or
other stop).
[0100] At 208, the controller 58 determines whether the vehicle 10
meets the required leak check frequency. For example, the required
leak check frequency may be federally regulated, vehicle
manufacturer regulated, or a combination of these. For example, the
required leak check frequency may be 26% of qualifying trips
(according to current CARB OBD2 regulations).
[0101] If true at 208, method 200 ends at 212. If false at 208, the
method 200 determines whether the vehicle 10 meets the required
small leak test conditions at 214. For example, the conditions may
include: the fuel tank must be 1/2/3/4 full, the ambient outside
temperature must not be too hot or too cold (for example greater
than 95.degree. F. or less than 30.degree. F.), the vehicle must
meet engine cold start conditions (for example, sat overnight or
for at least 8 hours without being driven; engine coolant
temperature is less than or equal to 12.degree. F. higher than
ambient temperature, etc.), the vehicle must have been driven for a
minimum number of minutes (for example 10 minutes) within a speed
range (for example 45-65 mph), the components in the EVAP control
system must be functioning normally, there must not be any fault
codes, or a combination thereof. If false, method 200 ends at
212.
[0102] If true at 214, method 200 receives a V2X communication at
216. For example, the controller 58 may ping infrastructure,
vehicles, pedestrian, etc., in the vicinity (for example, within a
2-mile radius) to determine the length of the stop (for example,
through the antenna 26). The controller 58 may receive an output
from the V2X communication system 78 providing details on the
length of stop.
[0103] For example, if the vehicle 10 is stopped at a traffic
light, the V2X communication system 78 may communicate with the
communications of the traffic light infrastructure to determine
light timing. Based on the stop time, or based on the signal from
the traffic light infrastructure, the controller 58 may determine
the remaining stop time at the traffic light.
[0104] For example, if the vehicle 10 is stopped at a train stop,
the V2X communication system 78 may communicate with the train stop
infrastructure to determine timing. Based on the signal from the
train stop infrastructure (which may include train length, train
speed, time until light change, etc.), the controller 58 may
determine the remaining stop time at the train stop.
[0105] For example, if the vehicle 10 is stopped at a traffic
accident, the V2X communication system 78 may communicate with a
network communication or a police officer vehicle communication to
determine a stop time. The stop time may be based on a severity of
the accident, time already stopped, projected time until the
accident clears, etc. Based on the signal from the network
communication or police officer vehicle communication, the
controller 58 may determine the remaining stop time at the
accident.
[0106] At 220, method 100 may determine whether the remaining stop
time is greater than a threshold. For example, the threshold may be
10 minutes or greater. For example, the controller 58 may vary the
predetermined threshold based on fuel level.
[0107] If false at 220, method 200 ends at 212.
[0108] If true at 220, the method 200 may perform the leak check by
any suitable means at 224. For example, the controller 58 may shut
the engine 38 off for a predetermined time (such as 30 minutes or
more). The controller 58 may then restart the engine 38 and command
the engine 38 to idle at a predetermined speed (for example, within
a range of 400-800 RPM) for a predetermined idle time (for example,
10 minutes or more). During the engine idle time, the controller 58
may execute the small leak test, as previously described.
[0109] Method 200 ends at 116.
[0110] Now referring to FIG. 5, an alternative example method 300
for performing a leak check is illustrated. Method 300 begins at
304. At 304, the vehicle 10 is started and driving.
[0111] At 308, the controller 58 determines whether the vehicle 10
meets the required leak check frequency. For example, the required
leak check frequency may be federally regulated, vehicle
manufacturer regulated, or a combination of these. For example, the
required leak check frequency may be 26% of qualifying trips
(according to current CARB OBD2 regulations).
[0112] If true at 308, method 300 ends at 312. If false at 308, the
method 300 determines whether the vehicle 10 meets the required
small leak test conditions at 314. For example, the conditions may
include: the fuel tank must be 1/2-3/4 full, the ambient outside
temperature must not be too hot or too cold (for example greater
than 95.degree. F. or less than 30.degree. F.), the vehicle must
meet engine cold start conditions (for example, sat overnight or
for at least 8 hours without being driven; engine coolant
temperature is less than or equal to 12.degree. F. higher than
ambient temperature, etc.), the vehicle must have been driven for a
minimum number of minutes (for example 10 minutes) within a speed
range (for example 45-65 mph), the components in the EVAP control
system must be functioning normally, there must not be any fault
codes, or a combination thereof. If false, method 300 ends at
312.
[0113] If true at 314, method 300 may evaluate a drive route and
ping infrastructures, vehicles, networks, pedestrians, etc., for
traffic and road conditions along the drive route at 316. For
example, the controller 58 may communicate with the navigation
system 18 to determine the drive route. The navigation system 18
may determine vehicle location and drive route from the GPS 34 or
GNSS 30 and stored maps, for example. The V2X communications system
78 may ping the infrastructures, vehicles, networks, pedestrians,
etc., along the drive route for traffic and road conditions, for
example, through antenna 26.
[0114] At 320, method 300 may receive communications from
infrastructure, vehicles, pedestrians, and networks along the drive
route. For example, the V2X communication system 78 may receive
system messages from the infrastructure-to-vehicle, V2V,
pedestrian-to-vehicle, or network-to-vehicle, collectively X2X,
systems indicating the traffic and road conditions. For example,
the communications may indicate locations of potholes, rough
pavement, uneven pavement, inclines and declines, road humps,
bends, turns, etc., in the road. The communications may
additionally, or alternatively, include vehicle frequency, average
vehicle speeds, vehicle concentrations, speed limits, traffic
lights, train stops, traffic accidents, etc.
[0115] At 324, method 300 may determine whether the road conditions
and traffic conditions are suitable for execution of the small leak
test. For example, the controller 58 may communicate with the
navigation system 18, the V2X communication system 78, or a
combination of these, to determine whether the road condition is
sufficiently smooth and level without bends and whether the traffic
condition is consistently moving at or near the posted speed limit
or the current vehicle speed. The sufficiency determination may be
based on whether the traffic conditions and road conditions support
consistent vehicular momentum which leads to fuel slosh levels less
than a predetermined threshold and vapor generation less than a
predetermined threshold in the fuel tank 46. For example, the fuel
level in the fuel tank 46 may not fluctuate more than the
predetermined threshold (for example, within a range of 5%-10%) and
the vapor in the fuel tank 46 may not increase by more than the
predetermined threshold (for example, within a range of 5%-10%).
For example, pressure in the fuel vapor space may not fluctuate
more than a predetermined pressure (for example, more than 5
kPa).
[0116] For example, the road condition may be sufficiently smooth
and level without bends if the incline or decline of the road does
not change more than 5% over a 2 mile stretch, if there are no
turns greater than 25.degree., if there are fewer potholes than a
range of 0-2 per 2 miles, if there are no rough pavement
conditions, if there are no uneven pavement conditions, and if
there are no road humps. For example, the traffic condition may be
sufficient for the small leak test if the average vehicle speed is
not less than the current vehicle speed for the vehicle 10 or is
not less than the posted speed limit, and there are no traffic
lights, train stops, or accidents.
[0117] If false at 324, method 300 ends at 312.
[0118] If true at 324, the method 300 may perform the leak check by
any suitable means at 328. For example, the controller 58 may shut
the engine 38 off for a predetermined time (such as 30 minutes or
more) and command the electric propulsion system 50 to propel the
vehicle 10. The controller 58 may then restart the engine 38 and
command the engine 38 to idle at a predetermined speed (for
example, within a range of 400-800 RPM) for a predetermined idle
time (for example, 10 minutes or more). During the engine idle
time, the controller 58 may execute the small leak test, as
previously described.
[0119] Method 300 ends at 312.
[0120] Now referring to FIG. 6, an alternative example method 400
for performing a leak check is illustrated. Method 400 begins at
404. At 404, the vehicle 10 is keyed-off.
[0121] At 408, the controller 58 determines whether the vehicle 10
meets the required leak check frequency. For example, the required
leak check frequency may be federally regulated, vehicle
manufacturer regulated, or a combination of these. For example, the
required leak check frequency may be 26% of qualifying trips
(according to current CARB OBD2 regulations).
[0122] If true at 408, method 400 ends at 412. If false at 408, the
method 400 determines whether the vehicle 10 meets the required
small leak test conditions at 414. For example, the conditions may
include: the fuel tank must be 1/2-3/4 full, the ambient outside
temperature must not be too hot or too cold (for example greater
than 95.degree. F. or less than 30.degree. F.), the vehicle must
have met engine cold start conditions (for example, sat overnight
or for at least 8 hours without being driven; engine coolant
temperature is less than or equal to 12.degree. F. higher than
ambient temperature, etc.), the vehicle must have been driven for a
minimum number of minutes (for example 10 minutes) within a speed
range (for example 45-65 mph), the components in the EVAP control
system must be functioning normally, there must not be any fault
codes, or a combination thereof. If false, method 400 ends at
412.
[0123] If true at 414, the method 400 may receive a signal from the
ride-share application 22 indicating the next scheduled fare time
and location at 416. For example, the controller 58 may communicate
with the ride-share application 22 to determine the time and
location of the next scheduled fare. The controller 58 may
communication with the navigation system 18 to determine a route
and drive time to the pickup location of the next scheduled
fare.
[0124] At 420, method 400 may determine an idle time remaining
before the next scheduled fare. For example, the idle time
remaining may be the amount of time that the vehicle 10 may remain
parked in the current location before needing to leave for the
pickup location.
[0125] In an example scenario, the controller 58 may have received
communications from the ride-share application 22 that the next
fare is scheduled for pickup at a location 3 miles from the current
location of the vehicle 10 in 35 minutes from the present time. The
controller 58 may communicate with the navigation system 18 to
determine that a shortest route to the pickup location takes 10
minutes. Thus, the idle time remaining may be approximately 25
minutes.
[0126] At 424, method 400 may determine whether the idle time is
greater than a threshold time. For example, the controller 58 may
compare the idle time remaining with a predetermined threshold. The
predetermined threshold may be the required time for completing the
small leak test. For example, the predetermined threshold may be 10
minutes or more. For example, the controller 58 may vary the
predetermined threshold based on fuel level.
[0127] If true at 424, the method 400 may perform the leak check by
any suitable means at 428. For example, the controller 58 may
determine whether the vehicle has been shut down for a
predetermined time (such as 30 minutes or more). If true, the
controller 58 may restart the engine 38 and command the engine 38
to idle at a predetermined speed (for example, within a range of
400-800 RPM) for a predetermined idle time (for example, 10 minutes
or more). If false, the controller 58 may keep the engine 38 shut
down for the predetermined time and then restart the engine 38 and
command the engine 38 to idle at the predetermined speed for the
predetermined time. During the engine idle time, the controller 58
may execute the small leak test, as previously described.
[0128] If false at 424, a signal may be sent to the ride-share
application 22 to make the vehicle 10 unavailable for the required
leak check time. For example, the controller 58 may send a signal
to the ride-share application 22 to either postpone the pickup time
for a time that allows the small leak check to complete or deny the
next scheduled fare for the vehicle 10.
[0129] The ride-share application 22 may make the determination of
which option to select. For example, if the pickup time would be
postponed by less than a threshold (for example less than 10
minutes), the ride-share application 22 may postpone the pickup
time. If the pickup time would be postponed by 10 minutes or more,
the ride-share application 22 may cancel the pickup for the vehicle
10 and reschedule for an available vehicle.
[0130] Considering (and adding to) our previous example, if the
idle time remaining is approximately 25 minutes, and the vehicle
has been shut down for 10 minutes, the vehicle 10 may require an
additional 5 minutes over the idle time remaining to complete the
small leak check (if the predetermined shut down time is 30 minutes
and the predetermined idle time is 10 minutes). Thus, the
controller 58 may send a signal to the ride-share application 22
indicating that an additional 5 minutes are required before pickup.
Accordingly, the ride-share application 22 may either postpone the
pickup time or reschedule the pickup.
[0131] At 428, the small leak test may be performed, as previously
described.
[0132] Method 400 ends at 412.
[0133] The foregoing description of the embodiments has been
provided for purposes of illustration and description. It is not
intended to be exhaustive or to limit the disclosure, its
application, or uses. Individual elements or features of a
particular embodiment are generally not limited to that particular
embodiment, but, where applicable, are interchangeable and can be
used in a selected embodiment, even if not specifically shown or
described. The same may also be varied in many ways. Such
variations are not to be regarded as a departure from the
disclosure, and all such modifications are intended to be included
within the scope of the disclosure.
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