U.S. patent application number 15/224556 was filed with the patent office on 2018-02-01 for vehicle control unit and method to improve vehicle fuel efficiency based on an acceleration parameter.
The applicant listed for this patent is Toyota Motor Engineering & Manufacturing North America, Inc.. Invention is credited to Sergei I. Gage, Arata Sato.
Application Number | 20180029611 15/224556 |
Document ID | / |
Family ID | 60956774 |
Filed Date | 2018-02-01 |
United States Patent
Application |
20180029611 |
Kind Code |
A1 |
Gage; Sergei I. ; et
al. |
February 1, 2018 |
VEHICLE CONTROL UNIT AND METHOD TO IMPROVE VEHICLE FUEL EFFICIENCY
BASED ON AN ACCELERATION PARAMETER
Abstract
Provided is a method and device for providing feedback for
constant acceleration in a vehicle, which includes sampling
velocity data at sample rate during an increase in a velocity rate
over time to produce a plurality of sampled velocity data. An
acceleration parameter is generated based on a difference of the
sampled velocity data over a respective time interval. A
determination is made as to whether the acceleration parameter
indicates a constant acceleration. When the acceleration parameter
does indicate a constant acceleration, a near real-time feedback
signal is produced and announced to advise of the constant
acceleration.
Inventors: |
Gage; Sergei I.; (Redford,
MI) ; Sato; Arata; (Ann Arbor, MI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Toyota Motor Engineering & Manufacturing North America,
Inc. |
Erlanger |
KY |
US |
|
|
Family ID: |
60956774 |
Appl. No.: |
15/224556 |
Filed: |
July 31, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B60W 50/14 20130101;
B60W 2520/10 20130101; B60W 40/107 20130101; B60W 2050/0026
20130101; B60W 2520/105 20130101; B60W 50/16 20130101; Y02T 10/84
20130101 |
International
Class: |
B60W 50/14 20060101
B60W050/14; B60W 50/16 20060101 B60W050/16; B60W 40/107 20060101
B60W040/107 |
Claims
1. A method in a vehicle control unit, the method comprising:
sampling velocity data at sample rate during an increase in a
velocity rate over time to produce a plurality of sampled velocity
data; generating an acceleration parameter based on a difference of
the sampled velocity data over a respective time interval;
determining whether the acceleration parameter indicates a constant
acceleration based on a linear increase trajectory of the velocity
rate over time; and when the acceleration parameter indicates the
constant acceleration: producing a near real-time feedback signal
to advise of the constant acceleration; and announcing, via an
instrument cluster assembly, the near real-time feedback signal for
affecting a vehicle operator's acceleration behavior to maintain a
desirable constant acceleration rate.
2. The method of claim 1, wherein the determining whether the
acceleration parameter indicates the constant acceleration by:
comparing the acceleration parameter with a projected linear
rate-of-change velocity trend being based on at least in part on
some of the plurality of the sampled velocity data over the
respective time interval.
3. The method of claim 1, wherein further comprising: scaling
respective ones of a plurality of respective time intervals to an
adjusted respective time interval based on an initial acceleration
parameter exceeding a threshold for an initial time interval.
4. The method of claim 1, wherein the acceleration parameter is a
positive acceleration parameter.
5. The method of claim 1, further comprising: sensing the increase
in the velocity rate over time by an accelerometer sensor
device.
6. The method of claim 5, wherein the accelerometer sensor device
comprising at least one of: a capacitative accelerometer; a
piezoelectric accelerometer; a semiconductor accelerometer; and a
hall-effect accelerometer.
7. The method of claim 1, wherein the announcing the near real-time
feedback signal comprising at least one of: displaying a visual
indicator; providing a haptic indication; and providing an audible
indication.
8. A method in a vehicle control unit, the method comprising:
sensing an increase in a velocity rate over time; sampling velocity
data at a sample rate during the increase in the velocity rate over
time to produce a plurality of sampled velocity data; generating an
acceleration parameter for a first time interval, wherein the
acceleration parameter reflects a difference of the sampled
velocity data over the first time interval; generating a subsequent
acceleration parameter based on the difference of the sampled
velocity data over a second time interval; determining whether the
subsequent acceleration parameter indicates constant acceleration
based on a linear increase trajectory in the velocity rate over
time with respect to the initial acceleration parameter; and when
the subsequent acceleration parameter indicates the constant
acceleration: producing a near real-time feedback signal to advise
of the constant acceleration; and announcing, via an instrument
cluster assembly, the near real-time feedback signal for affecting
a vehicle operator's acceleration behavior.
9. The method of claim 8, wherein the determining whether the
subsequent acceleration parameter indicates the constant
acceleration by: comparing the subsequent acceleration parameter
with a projected linear rate-of-change velocity trend being based
on at least in part on the initial acceleration parameter.
10. The method of claim 8, further comprising: normalizing the
plurality of the sampled velocity data to minimize aberrations in
the plurality of sampled velocity data produced under different
operational conditions.
11. The method of claim 8, further comprising: sensing the increase
in the velocity rate over time with an accelerometer sensor
device.
12. The method of claim 11, wherein the accelerometer sensor device
comprising at least one of: a capacitative accelerometer; a
piezoelectric accelerometer; a semiconductor accelerometer; and a
hall-effect accelerometer.
13. The method of claim 8, wherein the announcing the near
real-time feedback signal comprising at least one of: a visual
indication signal; a haptic indication signal to either of a
vehicle control surface and a handheld user device; and a
resistance indication signal to either of a vehicle control surface
and a handheld user device.
14. A vehicle control unit comprising: a wireless communication
interface to service communication with a handheld user device of a
vehicle user and with a vehicle network; a processor coupled to the
wireless communication interface and in communication with a
vehicle speed sensor device, the processor for controlling
operations of the vehicle control unit; and a memory coupled to the
processor, the memory for storing data and program instructions
used by the processor, the processor configured to execute
instructions stored in the memory to: sample velocity data,
produced by the vehicle speed sensor device, at sample rate during
an increase in a velocity rate over time to produce a plurality of
sampled velocity data; generate an acceleration parameter for a
time interval, wherein the acceleration parameter reflects a
difference of the sampled velocity data with respect to the time
interval; determine whether the acceleration parameter indicates
constant acceleration based on a linear increase trajectory in the
velocity rate over time; and when the acceleration parameter
indicates the constant acceleration: produce a near real-time
feedback signal to advise of the constant acceleration; and
announce the near real-time feedback signal via the wireless
communication interface for receipt by the handheld user device of
a vehicle user to affect a vehicle operator's acceleration behavior
to maintain a desirable constant acceleration rate.
15. The vehicle control unit of claim 14, wherein the processor
further configured to execute further instructions stored in the
memory to determine whether the acceleration parameter indicates
the constant acceleration by: comparing the acceleration parameter
with a slope of a projected linear rate-of-change velocity trend
based on at least some of the plurality of the sampled velocity
data.
16. The vehicle control unit of claim 14, wherein the processor
further configured to execute further instructions stored in the
memory to scale a subsequent time interval to an adjusted time
interval based on an acceleration parameter exceeding a threshold
for the time interval.
17. The vehicle control unit of claim 14, wherein the acceleration
parameter comprising a positive acceleration parameter.
18. The vehicle control unit of claim 14, wherein the processor is
in communication with an acceleration sensor device to sense the
increase in the velocity rate over time.
19. The vehicle control unit of claim 18, wherein the acceleration
sensor device comprises at least one of: a capacitative
accelerometer; a piezoelectric accelerometer; a semiconductor
accelerometer; and a hall-effect accelerometer.
20. The vehicle control unit of claim 14, wherein the processor
being further configured to execute further instructions stored in
the memory to announce the near real-time feedback signal by at
least one of: displaying a visual indicator; providing a haptic
indication to either of a vehicle control surface and the handheld
user device; and providing a resistance indication to either of the
vehicle control surface and the handheld user device.
Description
BACKGROUND
[0001] Vehicle fuel price increases, either in the form of
electricity and/or petroleum-based fuels, provides challenges in
maximizing fuel efficiency to realize the best cost per distance
traveled. Apart from a fuel-efficient design of a vehicle power
train, an example to improve fuel efficiency is to correspondingly
improve the vehicle operator's driving habits towards a less
aggressive driving style. It is desirable to provide a driver
feedback on their driving habits to improve a vehicle's fuel
efficiency.
SUMMARY
[0002] A device and method for improving vehicle fuel efficiency
based on feedback for a vehicle acceleration parameter are
disclosed.
[0003] In one implementation, a method in a vehicle control unit is
disclosed. The method includes operations for sampling velocity
data at sample rate during an increase in a velocity rate over time
to produce a plurality of sampled velocity data. The method
generates an acceleration parameter based on a difference of the
sampled velocity data over a respective time interval. Proceeding,
the method determines whether the acceleration parameter indicates
a constant acceleration for a vehicle. When a constant acceleration
is present, the method produces a near real-time feedback signal to
advise of the constant acceleration, and announces the near
real-time feedback signal.
[0004] In another implementation, a vehicle control unit is
disclosed. The vehicle control unit may include a wireless
communication interface, a processor, and a memory.
[0005] The wireless communication interface services communication
with handheld user device of a vehicle user and with a vehicle
network. The processor is coupled to the wireless communication
interface and in communication with a vehicle speed sensor device,
where the processor is for controlling operations of the vehicle
control unit. The memory is coupled to the processor, and is for
storing data and program instructions used by the processor.
[0006] The processor being configured to execute instructions
stored in the memory to sample velocity data, produced by the
vehicle speed sensor device, at a sample rate during an increase in
a velocity rate over time to produce a plurality of sampled
velocity data and generate an acceleration parameter based on a
difference of the sampled velocity data over a respective time
interval. The processor is operable to determine whether the
acceleration parameter indicates a constant acceleration for a
vehicle. When the constant acceleration is present, processor
produces a near real-time feedback signal to advise of the constant
acceleration, and announces the near real-time feedback signal via
the wireless communication interface.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The description makes reference to the accompanying drawings
wherein like reference numerals refer to like parts throughout the
several views, and wherein:
[0008] FIG. 1 is a schematic illustration of a vehicle including a
vehicle control unit;
[0009] FIG. 2 shows a block diagram of the vehicle control unit of
FIG. 1 in the context of a vehicle network environment;
[0010] FIG. 3 shows a block diagram of the vehicle control unit of
FIGS. 1 and 2;
[0011] FIG. 4 is an example velocity-time graph illustrating a
variable acceleration trajectory for a vehicle;
[0012] FIG. 5 is an example velocity-time graph illustrating a
constant acceleration trajectory for a vehicle with the near
real-time feedback signal indicating a constant vehicle
acceleration;
[0013] FIG. 6 is an example velocity-time graph illustrating a
constant acceleration trajectory for a vehicle with the near
real-time feedback signal exceeding an acceleration threshold;
and
[0014] FIG. 7 is an example process in a vehicle control unit to
whether an acceleration state is constant and to provide a near
real-time feedback signal in response.
DETAILED DESCRIPTION
[0015] Generally, fuel-efficient driving habits of a vehicle
operator have been based on their traveling speed, or velocity. For
example, the vehicle fuel-efficiency correspondingly falls as the
traveling velocity increases. That is, fuel efficiency is greater
traveling at 30 mph (48 km/h) than at 80 mph (128 km/h).
[0016] With respect to vehicle acceleration, by analogy, the
greater fuel efficiency was considered to be achievable at a lower
rate of acceleration as opposed to a higher rate of acceleration.
However, acceleration rate does not affect fuel efficiency.
Instead, whether the acceleration is constant determines whether
fuel efficiency is improved.
[0017] Vehicles generally include feedback for fuel efficient
driving habits. For example, during constant velocity (such as
moderate highway speed), a visual indicator lights (such as in the
vehicle instrument cluster) to provide the operator feedback that
they are driving in a fuel efficient manner. However, when the
amount of acceleration exceeds an upper limit (for example,
depressing the accelerator pedal to the vehicle floor), the visual
indicator turns off, as well as when the vehicle velocity exceeds a
moderate highway speed (for example, about 80 mph (130 km/h)).
[0018] FIG. 1 is a schematic illustration of a vehicle 100
including a vehicle control unit 200. A plurality of sensor devices
102 are in communication with the control unit 200.
[0019] The plurality of sensor devices 102 can be positioned on the
outer surface of the vehicle 100, or may be positioned in a
concealed fashion for aesthetic purposes with regard to the
vehicle. Moreover, the sensors may operate at frequencies in which
the vehicle body or portions thereof appear transparent to the
respective sensor device. Communication between the sensors may be
on a bus basis, and may also be used or operated by other systems
of the vehicle 100. For example, the sensors devices 102 may be
coupled by a combination of network architectures such as a Body
Electronic Area Network (BEAN), a Controller Area Network (CAN) bus
configuration, an Audio Visual Communication-Local Area Network
(AVC-LAN) configuration, and/or other combinations of additional
communication-system architectures to provide communications
between devices and systems of the vehicle 100. Moreover, the
sensor devices 102 may be further coupled to the vehicle control
unit 200 via such communication-system architectures.
[0020] The sensor devices 102 operate to monitor ambient conditions
relating to the vehicle 100, including audio, visual, and tactile
changes to the vehicle environment.
[0021] One or more of the sensor devices 102 can be configured to
capture changes in velocity, acceleration, and/or distance to these
objects in the ambient conditions of the vehicle 100, as well as an
angle of approach. The sensor devices 102 may be provided by a
Light Detection and Ranging (LIDAR) system, in which the sensor
devices 102 may capture data related to laser light returns from
physical objects in the environment of the vehicle 100. The sensor
devices 102 may also include a combination of lasers (LIDAR) and
milliwave radar devices.
[0022] In various driving modes, the examples of the placement of
the sensor devices 102 may provide for blind-spot visual sensing
(such as for another vehicle adjacent the vehicle 100) relative to
the vehicle user, and for forward periphery visual sensing (such as
for objects outside the forward view of a vehicle operator, such as
a pedestrian, cyclist, etc.).
[0023] The vehicle 100 can also include options for operating in
manual mode, autonomous mode, and/or driver-assist mode. When the
vehicle 100 is in manual mode, the driver manually controls the
vehicle systems, which may include a propulsion system, a steering
system, a stability control system, a navigation system, an energy
system, and any other systems that can control various vehicle
functions (such as the vehicle climate or entertainment functions,
etc.). The vehicle 100 can also include interfaces for the driver
to interact with the vehicle systems, for example, one or more
interactive displays, audio systems, voice recognition systems,
buttons and/or dials, haptic feedback systems, or any other means
for inputting or outputting information.
[0024] In an autonomous mode of operation, a computing device,
which may be provided by the vehicle control unit 200, or in
combination therewith, can be used to control one or more of the
vehicle systems without the vehicle user's direct intervention.
Some vehicles may also be equipped with a "driver-assist mode," in
which operation of the vehicle 100 can be shared between the
vehicle user and a computing device.
[0025] For example, the vehicle operator can control certain
aspects of the vehicle operation, such as steering, while the
computing device can control other aspects of the vehicle
operation, such as braking and acceleration. When the vehicle 100
is operating in autonomous (or driver-assist) mode, the computing
device, such as the vehicle control unit 200, issues commands to
the various vehicle systems to direct their operation, rather than
such vehicle systems being controlled by the vehicle user.
[0026] As shown in FIG. 1, the vehicle control unit 200 is
configured to provide wireless communication with a user device
through the antenna 220, other vehicles (vehicle-to-vehicle),
and/or infrastructure (vehicle-to-infrastructure), or with devices
through a network cloud, which is discussed in detail with respect
to FIGS. 2-7.
[0027] Referring now to FIG. 2, a block diagram of the vehicle
control unit 200 in the context of a network environment is
provided. While the vehicle control unit 200 is depicted in
abstract with other vehicular components, the vehicle control unit
200 may be combined with the system components of the vehicle 100
(see FIG. 1). Moreover, the vehicle 100 may also be an automobile
or any other passenger or non-passenger vehicle such as, for
example, a terrestrial, aquatic, and/or airborne vehicle.
[0028] As shown in FIG. 2, a vehicle network 201 may include the
vehicle control unit 200, an audio/visual control unit 208, a
sensor control unit 214, and an engine control unit 240, that are
communicatively coupled via a network 212 and communication paths
213.
[0029] The vehicle control unit 200 may communicate with a head
unit device 202 via a communication path 213 and network 212, and
may also communicate with the sensor control unit 214 to access
sensor data 216 from sensor devices 102, 252, 254 and/or nnn. The
vehicle control unit 200 may also be wirelessly coupled with a
network cloud 218 via the antenna 220 and wireless communication
226, as well as via a wireless communication 238 to handheld user
devices such as handheld mobile device 236 (for example, cell
phone, a smart phone, a personal digital assistant (PDA) devices,
tablet computer, e-readers, etc.).
[0030] In this manner, the vehicle control unit 200 operates to
receive input data, such as sensor data 216, and provide data, to
the head unit device 202 via the audio/visual control unit 208, to
the sensor control unit 214, and to other devices that may
communicatively couple via the network 218, such as computer 224,
handheld mobile device 222 (for example, cell phone, a smart phone,
a personal digital assistant (PDA) devices, tablet computer,
e-readers, etc.).
[0031] The vehicle control unit 200 and the audio/visual control
unit 208 may be communicatively coupled to receive the sensor data
216 from the sensor control unit 214, including data values
relating to fuel consumption information.
[0032] The vehicle control unit 200 may provide data such as a near
real-time feedback signal 203 to indicate fuel efficient operation
of the vehicle 100 to a vehicle operator. The signal 203 may be
announced by example by displaying a visual indicator 205, by
providing a haptic indication 223, and/or by providing an audible
indication 237 to the vehicle operator, such as through head unit
device 202, handheld mobile devices 222 and/or 236, computer 224, a
combination of devices thereof, etc.
[0033] The use of the term "near real-time" or (NRT) refers to time
delay that may be introduced, by the vehicle control unit 200
processing velocity data from the VSS device 252, and/or time delay
that may be introduced by transmission of the velocity data over
the vehicle network 20, and transmission of the NRT feedback signal
203, etc., between the occurrence of an event (that is, sensing
instantaneous velocity of the vehicle), and the use of NRT feedback
signal 203 by the vehicle operator.
[0034] As discussed in detail herein, the vehicle control unit 200
operates to promote and/or improve fuel efficiency of the vehicle
100 through providing near real-time feedback 203. The near
real-time feedback is based upon promoting a constant acceleration
while moving from a first velocity through to a second velocity. As
noted, whether amount of acceleration (that is, faster or slower)
does not appreciably affect fuel efficiency, but greater fuel
efficiency may be recognized by maintaining the acceleration at a
constant rate, as is discussed in detail with reference to FIGS.
4-7.
[0035] The visual indicator 205 may also be provided via a
conventional instrument cluster assembly of the vehicle, such as an
indicator light (LED, LCD, backlit, etc.), graphic icon, etc. An
example of such a visual indicator 205 is an "eco driving indicator
light" that illuminates during eco-friendly operation.
[0036] Still referring to FIG. 2, the audio/visual control unit 208
operates to provide, for example, audio/visual data 209 for display
to the touch screen 206, as well as to receive user input data 211
via a graphic user interface. The audio/visual data 209 and input
data 211 may include audio data, hands-free phone data, voice
control data, navigation data, USB connection data, DVD play
function data, multifunction meter function data, illumination
signal data for the display 206 (such as dimming control), driving
status recognition data (such as vehicle speed, reverse, etc. via
sensor data 216), composite image signal data (such as data via
sensor devices 102), etc.
[0037] In FIG. 2, the head unit device 202 may include tactile
input 204 and a touch screen 206. The touch screen 206 operates to
provide visual output or graphic user interfaces such as, for
example, maps, navigation, entertainment, information,
infotainment, and/or combinations thereof.
[0038] The touch screen 206 may include mediums capable of
transmitting an optical and/or visual output such as, for example,
a cathode ray tube, a light emitting diode, a liquid crystal
display, a plasma display, or other two dimensional or three
dimensional display that displays graphics, text or video in either
monochrome or color in response to display data 209.
[0039] Moreover, the touch screen 206 may, in addition to providing
visual information, detect the presence and location of a tactile
input upon a surface of or adjacent to the display. Additionally,
it is noted that the touch screen 206 can include at least one or
more processors and one or more memory modules to support the
operations described herein.
[0040] The head unit device 202 may also include tactile input
and/or control inputs such that the communication path 213
communicatively couples the tactile input to other control units
and/or modules of the vehicle 100 (FIG. 1). The tactile input data
may provided by devices capable of transforming mechanical,
optical, or electrical signals into a data signal capable of being
transmitted via the communication path 213.
[0041] The tactile input 204 may include number of movable objects
that each transform physical motion into a data signal that can be
transmitted over the communication path 213 such as, for example, a
button, a switch, a knob, a microphone, etc.
[0042] The touch screen 206 and the tactile input 204 may be
combined as a single module, and may operate as an audio head unit
or an infotainment system of the vehicle 100. The touch screen 206
and the tactile input 204 can be separate from one another and
operate as a single module by exchanging signals via the
communication path 213 via audio/visual data 209 and/or user input
data 211.
[0043] The head unit device 202 may be provide information
regarding vehicle operation conditions based on display data 209
from the audio/visual control unit 208. Moreover, the
graphics-based instrument cluster display, or may provide a such
instrument cluster display to other monitor devices for the vehicle
100, such as a heads-up display (not shown), or to an instrument
cluster in the vehicle dash assembly behind the vehicle steering
wheel.
[0044] The audio/visual control unit 208 operates to receive user
input data 211, and provides display data 209. The display data 209
may include operational information based on the sensor data 216.
For example, the graphic user interface presented to the touch
screen 206 may include
[0045] The sensor control unit 214 provides access to sensor data
216 of the sensor devices 102, vehicle speed sensor (VSS) device
252, accelerometer sensor device 254, sensor device nnn, etc.
[0046] The VSS device 252 operates to measure
transmission/transaxle output and/or wheel speed to produce
velocity data. The VSS device 252 provides this information to
modify engine functions, such as ignition timing, transmission
shift points, etc. The VSS device 252 may further operate to
provide velocity data to the vehicle control unit 200, which may be
sampled at a sample rate during an increase in a velocity rate over
time to produce sampled velocity data.
[0047] Generally, speed or velocity is the distance traveled
divided by the time it takes. For example, when a distance of 200
kilometers (124 miles) takes four hours to do so, the average speed
is 50 kilometers per hour (31 mph).
[0048] For affecting fuel efficiency, the instantaneous speed,
which is the speed of the vehicle at a given moment, is sampled
during an increase in the velocity rate of time is processed and
generates an acceleration parameter. A near real-time feedback
signal 203 is based on a state (constant or variable) of the
acceleration parameters during the acceleration.
[0049] With respect to sensing velocity, the VSS device 252 may be,
for example, based upon magnetic components on a rotating drive
shaft that are detected by magnetic sensors (for example, reed
switches, Hall-effect sensors, etc.). Each pass generates a brief
electric current pulse. The sensor control unit 214 counts the rate
the current pulses arrive and converts the signal into velocity
data, which may be displayed by an instrument cluster. The vehicle
control unit 200 samples the velocity data to assess the nature of
an acceleration rate (constant or variable) and produces a near
real-time feedback signal to advise when constant acceleration is
attained.
[0050] The accelerometer sensor device 204 operates to sense proper
acceleration of the vehicle 100 in terms of g-force, but not
coordinate acceleration (that is, a rate of change of velocity).
Such changes in g-force may operate to sense, generally, an
increase in the velocity rate over time, as a precursor to a
vehicle operator applying an acceleration to an increase in vehicle
velocity.
[0051] As may be appreciated, accelerometer are generally
impracticable for velocity estimation or vehicle acceleration
estimation. Accelerometers generally operate to sense a change in
force, based on the principle of force equals mass times
acceleration.
[0052] For example, to perhaps use an accelerometer for the purpose
of velocity estimation, the device must first be installed with an
exceedingly high degree of accuracy so that gravity measurements
may be distinguished from the physical acceleration of the
device.
[0053] Accordingly, with respect to the embodiments discussed
herein, the accelerometer sensor device 204 may be used to sense
general force changes to the vehicle 100, and to provide a point to
monitor a vehicle's instantaneous velocity to provide feedback to
affect the nature of the acceleration applied.
[0054] For example, while at a stop (where velocity is zero) or at
constant speed (when velocity is generally unchanged over time),
the accelerometer sensor device 204 senses a zero g-force. When an
increase in a velocity rate over time occurs, however, the
accelerometer sensor device 204 senses a non-zero g-force, where
the g-force is greater than zero. In this regard, the accelerator
sensor device 204 provided sensor data 216 for the vehicle control
unit 200 to detect the nature of an acceleration by a vehicle
user.
[0055] The accelerator sensor device 254 may be implemented, for
example, as a capacitative accelerometer, a piezoelectric
accelerometer, a semiconductor accelerometer, a Hall-effect
accelerometer, etc. Generally, the acceleration sensor device 254
may be provided by a device capable of sensing forces (that is,
force equals mass times acceleration) exerted on the vehicle 100 by
a change in acceleration (such as changing from a stationary
position, moving from a first velocity to a second velocity,
etc.).
[0056] The sensor data 216 may also operate to permit object
detection external to the vehicle, such as for example, other
vehicles (including vehicles occupying a parking location), roadway
obstacles, traffic signals, signs, trees, etc. Accordingly, the
sensor data 216 allows the vehicle 100 (see FIG. 1) to assess its
environment in order to maximize safety for vehicle passengers and
objects and/or people in the environment.
[0057] The engine control unit (ECU) 240 may communicate with a
head unit device 202 via a communication path 213 and network 212,
and may also communicate with the sensor control unit 214 to access
sensor data 216 from sensor devices 102, 252, 254 and/or nnn.
[0058] The engine control unit 240 may function to control internal
combustion engine actuators to obtain a desired engine performance.
The engine control unit 240 operates to read the sensor data 216,
interpret the sensor data 216 based on multidimensional performance
maps or lookup tables, and adjust the engine actuators
accordingly.
[0059] For example, desired engine performance may be based on
operational modes, including an economy mode, a sport mode, a drive
mode, etc. The economy mode operates to mimic efficient driver
behavior to improve fuel economy by adjusting the vehicle torque
map, shift schedule, torque filtering, idle rpm speed, etc. The
economy mode may be further improved with influencing the nature of
the vehicle acceleration.
[0060] In addition to the providing a near real-time feedback
signal 203 to affect a vehicle operator's acceleration behavior,
the near real-time feedback signal 203 may be implemented by the
engine control unit 240 to also produce a constant acceleration
when the vehicle 100 may be in an economy mode while operating in a
manual mode, autonomous mode, and/or driver-assist mode. The near
real-time feedback signal 203 may also present an indication to the
vehicle operator as described herein to verify and/or confirm a
fuel efficient mode of operation by the vehicle 100.
[0061] As may be appreciated, the communication path 213 of the
vehicle network 201 may be formed by a medium suitable for
transmitting a signal such as, for example, conductive wires,
conductive traces, optical waveguides, or the like. Moreover, the
communication paths 213 can be formed from a combination of mediums
capable of transmitting signals.
[0062] The communication path 213 may be provided by a vehicle bus,
or combinations thereof, such as for example, a Body Electronic
Area Network (BEAN), a Controller Area Network (CAN) bus
configuration, an Audio Visual Communication-Local Area Network
(AVC-LAN) configuration, a Local Interconnect Network (LIN)
configuration, a Vehicle Area Network (VAN) bus, and/or other
combinations of additional communication-system architectures to
provide communications between devices and systems of the vehicle
100.
[0063] The term "signal" relates to a waveform (e.g., electrical,
optical, magnetic, mechanical or electromagnetic), such as DC, AC,
sinusoidal-wave, triangular-wave, square-wave, vibration, and the
like, capable of traveling through at least some of the mediums
described herein.
[0064] The wireless communication 226, 228 and/or 230 of the
network cloud 218 may be based on one or many wireless
communication system specifications. For example, wireless
communication systems may operate in accordance with one or more
standards specifications including, but not limited to, 3GPP (3rd
Generation Partnership Project), 4GPP (4th Generation Partnership
Project), 5GPP (5th Generation Partnership Project), LTE (long term
evolution), LTE Advanced, RFID, IEEE 802.11, Bluetooth, AMPS
(advanced mobile phone services), digital AMPS, GSM (global system
for mobile communications), CDMA (code division multiple access),
LMDS (local multi-point distribution systems), MMDS
(multi-channel-multi-point distribution systems), IrDA, Wireless
USB, Z-Wave, ZigBee, and/or variations thereof.
[0065] As is noted above, the vehicle control unit 200 may be
communicatively coupled to a computer 224 via wireless
communication 228, a handheld mobile device 222 via wireless
communication 230, etc.
[0066] As described in detail, application data may be provided to
the vehicle control unit 200 from various applications running
and/or executing on wireless platforms of the computer 224, the
handheld mobile device 222 and 236, as well as from the head unit
device 202 via the network 212.
[0067] The handheld mobile device 222 and/or computer 224, by way
of example, may be a device including hardware (for example,
chipsets, processors, memory, etc.) for communicatively coupling
with the network cloud 218, and also include an antenna for
communicating over one or more of the wireless computer networks
described herein.
[0068] FIG. 3 is a block diagram of a vehicle control unit 200,
which includes a wireless communication interface 302, a processor
304, and memory 306, that are communicatively coupled via a bus
308.
[0069] The processor 304 in the control unit 200 can be a
conventional central processing unit or any other type of device,
or multiple devices, capable of manipulating or processing
information. As may be appreciated, processor 304 may be a single
processing device or a plurality of processing devices. Such a
processing device may be a microprocessor, micro-controller,
digital signal processor, microcomputer, central processing unit,
field programmable gate array, programmable logic device, state
machine, logic circuitry, analog circuitry, digital circuitry,
and/or any device that manipulates signals (analog and/or digital)
based on hard coding of the circuitry and/or operational
instructions.
[0070] The memory and/or memory element 306 may be a single memory
device, a plurality of memory devices, and/or embedded circuitry of
the processor 304. Such a memory device may be a read-only memory,
random access memory, volatile memory, non-volatile memory, static
memory, dynamic memory, flash memory, cache memory, and/or any
device that stores digital information. The memory 306 is capable
of storing machine readable instructions such that the machine
readable instructions can be accessed by the processor 304. The
machine readable instructions can comprise logic or algorithm(s)
written in programming languages, and generations thereof, (e.g.,
1GL, 2GL, 3GL, 4GL, or 5GL) such as, for example, machine language
that may be directly executed by the processor 304, or assembly
language, object-oriented programming (OOP), scripting languages,
microcode, etc., that may be compiled or assembled into machine
readable instructions and stored on the memory 306. Alternatively,
the machine readable instructions may be written in a hardware
description language (HDL), such as logic implemented via either a
field-programmable gate array (FPGA) configuration or an
application-specific integrated circuit (ASIC), or their
equivalents. Accordingly, the methods and devices described herein
may be implemented in any conventional computer programming
language, as pre-programmed hardware elements, or as a combination
of hardware and software components.
[0071] Note that when the processor 304 includes more than one
processing device, the processing devices may be centrally located
(e.g., directly coupled together via a wired and/or wireless bus
structure) or may be distributed located (e.g., cloud computing via
indirect coupling via a local area network and/or a wide area
network). Further note that when the processor 304 implements one
or more of its functions via a state machine, analog circuitry,
digital circuitry, and/or logic circuitry, the memory and/or memory
element storing the corresponding operational instructions may be
embedded within, or external to, the circuitry comprising the state
machine, analog circuitry, digital circuitry, and/or logic
circuitry. Still further note that, the memory element stores, and
the processor 304 executes, hard coded and/or operational
instructions corresponding to at least some of the steps and/or
functions illustrated in FIGS. 1-7 to assess a nature of a vehicle
acceleration and to provide near real-time feedback features and
methods described herein.
[0072] The wireless communications interface 302 generally governs
and manages the vehicle user input data via the network 212 over
the communication path 213 and/or wireless communication 226. The
communication interface 302 also manages controller unit output
data such as display data and/or parking status data to the vehicle
user. There is no restriction on the present disclosure operating
on any particular hardware arrangement and therefore the basic
features herein may be substituted, removed, added to, or otherwise
modified for improved hardware and/or firmware arrangements as they
may develop.
[0073] The sensor data 216 (see FIG. 2) includes capturing of
intensity or reflectivity returns of the environment surrounding
the vehicle, instantaneous vehicle speed data, and acceleration
data for determining acceleration state for providing feedback to
improve vehicle fuel efficiency. In general, data 216 captured by
the sensor devices 102, 252, 254 and/or nnn and provided to the
vehicle network 201 via the communication path 213 can be used by
one or more of applications of the vehicle to assess acceleration
state(s) of the vehicle 100, and to provide the near real-time
feedback signal 203.
[0074] The antenna 220, with the wireless communications interface
206, operates to provide wireless communications with the vehicle
control unit 200, including wireless communication 226.
[0075] Such wireless communications range from national and/or
international cellular telephone systems to the Internet to
point-to-point in-home wireless networks to radio frequency
identification (RFID) systems. Each type of communication system is
constructed, and hence operates, in accordance with one or more
communication standards. For instance, wireless communication
systems may operate in accordance with one or more standards
including, but not limited to, 3GPP (3rd Generation Partnership
Project), 4GPP (4th Generation Partnership Project), SGPP (5th
Generation Partnership Project), LTE (long term evolution), LTE
Advanced, RFID, IEEE 802.11, Bluetooth, AMPS (advanced mobile phone
services), digital AMPS, GSM (global system for mobile
communications), CDMA (code division multiple access), LMDS (local
multi-point distribution systems), MMDS (multi-channel-multi-point
distribution systems), and/or variations thereof.
[0076] The structure of the vehicle control unit 200 may also be
used as an acceptable architecture of the audio/visual control unit
208, the sensor control unit 214, engine control unit (ECU) 240,
and other control units that may be included in the vehicle network
201 (see FIG. 2). The control units 208, 214, and 240 may each
include a communication interface, a processor, and memory that may
be communicatively coupled via a data bus. As may be appreciated,
other architectures may be implemented, with similar functional
capabilities.
[0077] The processors for the control units 208, 214 and 240 may be
a conventional central processing unit or any other type of device,
or multiple devices, capable of manipulating or processing
information. As may be appreciated, the processor may be a single
processing device or a plurality of processing devices. Such a
processing device may be a microprocessor, micro-controller,
digital signal processor, microcomputer, central processing unit,
field programmable gate array, programmable logic device, state
machine, logic circuitry, analog circuitry, digital circuitry,
and/or any device that manipulates signals (analog and/or digital)
based on hard coding of the circuitry and/or operational
instructions.
[0078] The memory and/or memory element for the control units 208,
214 and 240 may be a single memory device, a plurality of memory
devices, and/or embedded circuitry of the processor related to the
control units 208, 214 and 240. Such a memory device may be a
read-only memory, random access memory, volatile memory,
non-volatile memory, static memory, dynamic memory, flash memory,
cache memory, and/or any device that stores digital
information.
[0079] Note that if the processor for each of the control units
208, 214 and 240 includes more than one processing device, the
processing devices may be centrally located (e.g., directly coupled
together via a wired and/or wireless bus structure) or may be
distributed located (e.g., cloud computing via indirect coupling
via a local area network and/or a wide area network). Further note
that when the processor for each of the control units 208, 214 and
240 may implement one or more of its functions via a state machine,
analog circuitry, digital circuitry, and/or logic circuitry, the
memory and/or memory element storing the corresponding operational
instructions may be embedded within, or external to, the circuitry
comprising the state machine, analog circuitry, digital circuitry,
and/or logic circuitry. Still further note that, the memory element
stores, and the processor 704 executes, hard coded and/or
operational instructions corresponding to at least some of the
steps and/or functions illustrated in FIGS. 1-7 to perform
human-machine interface features and methods described herein.
[0080] The communications interface for each of the control units
208, 214 and 240 generally governs and manages the user input data
received via the network 212, and outbound data to/from the vehicle
control unit 200, respectively. There is no restriction on the
present disclosure operating on any particular hardware arrangement
and therefore the basic features herein may be substituted,
removed, added to, or otherwise modified for improved hardware
and/or firmware arrangements as they may develop.
[0081] FIG. 4 is an example velocity-time graph illustrating a
variable acceleration trajectory 400 for a vehicle 100 without the
near real-time feedback signal 203 indicating a constant
acceleration. In the example of FIG. 4, though an accelerator pedal
for the vehicle 100 may be constantly pressed, the vehicle's
velocity (indicated by the vertical axis) does not continue to
increase over time (horizontal axis), and the resulting
acceleration is variable over the span of moving from a first
velocity V.sub.0 to a second velocity V.sub.3. The accelerator
pedal for the vehicle functions to control a vehicle fuel throttle
to increase, or accelerate, the vehicle to a desired velocity. The
accelerator coupling to the fuel throttle may be an electronic
throttle control, a mechanical linkage, optical throttle control,
etc.
[0082] Factors slowing the rate of acceleration may include
aerodynamic drag on the vehicle, road friction, component friction,
engine efficiency, etc., as the vehicle 100 approaches a target
speed V.sub.target, which in the present example, is V.sub.3. The
variable acceleration trajectory 400 is a general example of the
acceleration behavior.
[0083] The feedback signal 203 operates to affect vehicle operation
to improve fuel efficiency by applying a constant acceleration
rate. The feedback signal 203 permits a vehicle operator,
responsive to the feedback signal 203, to manipulate accelerator
controls to maintain a desirable constant acceleration rate.
[0084] In the alternative, the feedback signal 203 may be applied
for engine control input, such as through an engine control unit
240, which operates to perform engine management functions
affecting vehicle performance, as discussed in detail with
reference to FIG. 2.
[0085] In the example of FIG. 4, the acceleration parameters are
generated for each of the time interval 404, 406, and 408, during
the increase in the velocity rate from first velocity V.sub.0 to a
second velocity V.sub.3. As may be appreciated the time interval
404 may be considered an interval may be considered an initial or
first time interval, and the remaining time intervals as subsequent
(or second interval, third interval, etc.) with respect to the
initial or first time interval 404.
[0086] An acceleration sensor device 254 senses the increase in the
velocity rate over time by the period before to, when the vehicle
100 is stopped (V.sub.0 is zero). The acceleration sensor device
254 senses motion of the vehicle because a force exerted by placing
the vehicle 100 in motion produces a g-force greater than zero.
[0087] The time intervals 404, 406 and 408 are scalable, and may be
configured based on driving habits of the vehicle operator. They
may be predetermined at time intervals sufficient to determine the
constant or variable state of the operator's acceleration during a
transition from a first velocity to a second velocity. Habitually
conservative acceleration may have longer time intervals sufficient
to sample velocity data, while habitually dynamic acceleration may
have shorter time intervals sufficient to sample the velocity data.
In instances in which a vehicle driver does not have an
acceleration tendency or habit for either acceleration rates, the
time intervals may be dynamically adjusted based on the
acceleration applied, as discussed in detail with reference to
FIGS. 5-7.
[0088] Also, as may be appreciated, the number of time intervals
404, 406 and 408 are provided for example purposes, because the
vehicle control unit 200 does not have a priori knowledge for the
vehicle operator's final velocity value, V.sub.target. In this
manner, the near real-time feedback signal 203 is based upon
instantaneous velocity data, which is sampled by the vehicle
control unit, and used to determine whether the vehicle 100
achieves constant acceleration on a transition from an initial
velocity V.sub.0 to a target velocity V.sub.target.
[0089] Still referring to FIG. 4, the acceleration parameter
m.sub.1 for the time interval 404 from time t.sub.0 to time t.sub.1
depicts an initial fast rate of positive acceleration (that is, a
positive acceleration parameter, as contrasted with a declaration
or negative acceleration parameter). For clarity, the resulting
acceleration parameters for the variable acceleration trajectory
400 are shifted upwards along the dotted line parallel to the
horizontal axis. The acceleration parameter m.sub.2 for the time
interval 406 from time t.sub.1 to time t.sub.2 levels out in
contrast to the acceleration parameter m.sub.1, indicating a slower
rate of acceleration. That is, the acceleration parameter m.sub.1
is not similar/equal to the acceleration parameter m.sub.2,
indicating variable and/or non-constant acceleration of the
acceleration trajectory 400.
[0090] The acceleration parameter m.sub.3 for the time interval 408
from time t.sub.2 to time t.sub.3 further levels out in contrast to
the acceleration parameter m.sub.2, indicating a yet slower rate of
acceleration. With respect to the different between the
acceleration parameter m.sub.2 to acceleration parameter m.sub.3
may be within a selected tolerance, and effectively be similar to
one another, the assessment of acceleration parameters m1, m2 and
m3 indicate variable acceleration
(m.sub.1>m.sub.2.apprxeq.m.sub.3).
[0091] During the increase in the velocity rate from time t.sub.0
to time t.sub.3, the resulting non-uniform acceleration is in a
variable state. In the example of FIG. 4, the vehicle control unit
200 would not produce a near real-time feedback signal advising of
a constant acceleration.
[0092] FIG. 5 is an example velocity-time graph illustrating a
constant acceleration trajectory 500 for a vehicle 100 with the
near real-time feedback signal 203 indicating a constant vehicle
acceleration.
[0093] FIG. 5 illustrates sampled velocity data 502 plotted to the
velocity-time graph, which is sampled during an increase in the
velocity rate of the vehicle 100.
[0094] In the example of FIG. 5, the vehicle 100 begins from a
beginning velocity of V.sub.0. An acceleration sensor device 254
senses a transition in force from a g-force of approximately zero
Newtons to a g-force greater than zero Newtons.
[0095] During the increase in the velocity rate, vehicle control
unit 200 generates acceleration parameters m'.sub.1, m'.sub.2 and
m'.sub.3, which each acceleration parameter m'.sub.1, m'.sub.2 and
m'.sub.3, reflects a difference of the sampled velocity data over
the respective time interval. The slope value of the acceleration
parameter indicates the rate of acceleration for the vehicle 100
over time.
[0096] For determining whether a constant acceleration is occurring
for the trajectory 500, the acceleration parameters m'.sub.1,
m'.sub.2 and m'.sub.3 may be compared with one another as they are
generated by the vehicle control unit. For the example of FIG. 5,
the acceleration parameters m'.sub.1, m'.sub.2 and m'.sub.3
approximate one another, indicating a constant acceleration. Based
on this determination, the vehicle control unit produces the near
real-time feedback signal 203 to advise of the constant
acceleration.
[0097] With respect to time t, the feedback signal 203 may be
produced upon a first occurrence of attaining constant
acceleration, such as when the vehicle control unit 200 determine
that acceleration parameters m'.sub.1 and m'.sub.2 indicate
constant acceleration (at or about time t.sub.2), as well as that
acceleration parameters m'.sub.2 and m'.sub.3 (or all generated
acceleration parameters m'.sub.1, m'.sub.2 and m'.sub.3) indicate
constant acceleration (at or about time t.sub.3).
[0098] In the alternative, the vehicle control unit 200 may
determine that the each of the acceleration parameters m'.sub.1,
m'.sub.2 and m'.sub.3, separately or in combination, indicate a
constant acceleration based on a trend-line model. A trend-line
model operates to minimize the sum of squared deviations from the
sampled velocity data 502 measured in the vertical or "velocity"
direction on a permissible tolerance.
[0099] For example, the vehicle control unit 200 generates a
projected linear rate-of-change velocity trend 510 based on
historic sampled velocity data 502 (for example, sampled velocity
data during either or both of the time intervals 404 and 406). An
R-squared, or tolerance 520, minimizes or tolerates deviations in
the spread of the sampled velocity data 502 with respect to the
velocity trend 510.
[0100] As may be appreciated, when the vehicle control unit 200
initially places too tight tolerance to the velocity trend 510, a
vehicle operator may be able to sufficiently operate the
accelerator controls to come within the tolerance 520. Frustration
may result from not receiving a near real-time feedback signal 203
indicating constant acceleration (and also, may be considered
inoperative without ever receiving a positive feedback signal).
[0101] Accordingly, the vehicle control unit 200 may initially
(based on a reset mode, a "learning mode" from user input data 211,
etc.) loosens the tolerance to a permissive tolerance 520a. As the
vehicle operator becomes adept at managing the nuances of the
accelerator controls, the vehicle control unit 200 tightens the
tolerance 520 to a tolerance 520b the operator refines their
acceleration operation to further improve fuel efficiency for the
vehicle 100.
[0102] To also improve the modeling, the vehicle control unit 200
may normalize the sampled velocity data 502. Normalizing the
sampled velocity data 502 operates to minimize aberrations
indicated by aberration data 512 in the velocity data under
different operational conditions of the vehicle 100. The aberration
data 512 may be normalized to come within the expected spread of
the sampled velocity data 502, such as within tolerance 520.
Aberrations captured by the aberration data 512 may result due to
rough road conditions, vehicle transmission shifts move the vehicle
from a starting velocity to a target velocity, momentary
distraction by a vehicle operator, etc.
[0103] As may also be appreciated, acceleration parameter m'.sub.1
may span more than one time interval, such as the time interval 404
and the time interval 406. In effect, the acceleration parameter
m'.sub.1 may be combined with the acceleration parameter m'.sub.2.
In this manner, the acceleration parameter m'.sub.1 may keep pace
with the vehicle 100 while determining constant acceleration based
upon a slope of the projected linear rate-of-change velocity trend
510, which may be updated as the vehicle control unit 200 generates
further sampled velocity data 502 as the vehicle 100 approaches a
velocity target.
[0104] FIG. 6 is an example diagram velocity-time graph
illustrating a constant acceleration trajectory 600 for a vehicle
100 with the near real-time feedback signal 203 indicating a
constant vehicle acceleration.
[0105] FIG. 6 illustrates sampled velocity data 502 plotted to the
velocity-time graph, which is sampled during an increase in the
velocity rate of the vehicle 100. The vehicle 100 began from a
velocity of V.sub.0, with an unknown target velocity V.sub.U. The
acceleration sensor device 254 senses a transition in force from a
g-force of approximately zero N to a g-force greater than zero
N.
[0106] As noted, the vehicle control unit 200 samples velocity data
provided via the sensor data 216 at a sample rate (t.sub.s) 504. As
may be appreciated, the time intervals 404, 406, and 408 may be
adjusted to increase or decrease the amount of sampled velocity
data 502 per time interval based on the acceleration rate indicated
by an acceleration parameter. In the example of FIG. 6, the
acceleration rate for the vehicle exceeds an acceleration threshold
m.sub.t. As noted above, fuel efficiency increases with constant
acceleration, and not based upon whether the acceleration is "fast"
or "slow."
[0107] Because of the acceleration rate, the vehicle 100 may reach
a target velocity V.sub.target before the vehicle control unit 200
may determine whether constant acceleration is occurring, and to
provide a feedback signal 203. In this regard, the time intervals
are reduced to capture the acceleration state for trajectory
600.
[0108] For example, following generation of an acceleration
parameter m.sub.1, which has a .DELTA.V from V.sub.00 to V.sub.06
over a time interval (.DELTA.t) 404, the vehicle control unit 200
determines the acceleration rate, as indicated by the acceleration
parameter m.sub.1, exceeds the acceleration threshold m.sub.t. In
the example provided, the acceleration threshold m.sub.t has a rise
of .DELTA.V.sub.t with three velocity units (the difference of
V.sub.03 from V.sub.00), and the time interval .DELTA.t, such as
time interval 404.
[0109] The vehicle control unit 200 operates to scale subsequent
time intervals to produce adjusted time intervals (.DELTA.t'). For
example, the vehicle control unit 200 produces adjusted time
interval 606 for time t.sub.1 to t'.sub.2, 608 for time t'.sub.2 to
t'.sub.3, 610 for time t'.sub.3 to t'4, etc. The duration of the
adjusted time intervals (.DELTA.t') may also be based upon a
realistic maximum velocity V.sub.max for the vehicle 100. That is,
the target velocity V.sub.target is unlikely to exceed the maximum
velocity V.sub.max.
[0110] As may also be appreciated, acceleration parameter m.sub.1
may span more than one time interval, such as the time interval 404
and the adjusted time interval 606. In this manner, the
acceleration parameter m.sub.1 may keep pace with the vehicle 100
while determining constant acceleration based upon the projected
linear rate-of-change velocity trend 510, which may be updated as
the vehicle control unit 200 generates further sampled velocity
data 502.
[0111] Though the adjusted time interval has a lower threshold, the
accelerometer parameter m.sub.2 has a value that when the
acceleration is constant, will approximate the preceding
acceleration parameter m.sub.1 to indicate a constant acceleration.
Also, the vehicle control unit 200 may compare the accelerometer
parameter m.sub.2 with the projected linear rate-of-change velocity
trend 510 to determine whether a constant acceleration is
indicated.
[0112] FIG. 7 is an example process 700 in a vehicle control unit
200 determining constant acceleration by a vehicle and providing a
near real-time feedback signal in response.
[0113] In operation 702, the vehicle control unit, during an
increase in a velocity rate, samples velocity data at given sample
rate. The vehicle control unit produces from the velocity data
sampled velocity data during the increase in velocity rate. As may
be appreciated, the vehicle control unit may sense initiation (and
achieving a target velocity) by an acceleration force sensed by
acceleration sensor device 254 (see FIG. 2), and may receive
velocity data for the vehicle 100 from the VSS device 252 (see FIG.
2).
[0114] The vehicle control unit 200, at operation 704, generates an
acceleration parameter based on a difference of the sampled
velocity data over a respective time interval. When the
acceleration is constant, the acceleration parameter reflects a
substantially linear slope. The acceleration considered in the
embodiments herein are for positive acceleration parameters (such
as positive slopes, and degree of slopes), wherein a negative
acceleration connotes deceleration (or negative slopes and degree
of slopes), such as via applying an engine brake, wheel brakes,
downshifting, etc.
[0115] At operation 706, the vehicle control unit 200 determines
whether the acceleration parameter indicates a constant
acceleration based on a linear increase of the velocity rate over
time. The determination for constant acceleration may be based on
one or several bases, taking into consideration the generally brief
period of time to accelerate from a first velocity to a second, or
target velocity. For example, an acceleration parameter may be
assessed at successive time intervals, with each time interval
having a respective acceleration parameter. When the acceleration
is constant, the acceleration parameters are substantially
equal.
[0116] As another example, a projected linear rate-of-change
velocity trend 510 may be generated based on at least some of the
sampled velocity data from a time interval. A generated
acceleration parameter may then be compared with the slope of the
velocity trend 510 (see, e.g., FIG. 5), and when the comparison
indicates the acceleration parameter substantially equals the trend
slope, the acceleration parameter indicates a constant
acceleration.
[0117] In yet another example, the acceleration parameter is
cumulative over time as the vehicle progresses through the increase
in velocity. That is, a singular acceleration parameter may extend
over multiple time intervals, which then may also use the velocity
trend 510 as a reference for indicating constant acceleration. As
yet another example, subsequent discrete acceleration parameters
for a respective time interval may be compared against one another,
or against the velocity trend 510.
[0118] When the acceleration parameter indicates a constant
acceleration at operation 708, the vehicle control unit produces a
near real-time feedback signal to advise of the constant
acceleration. The near real-time feedback signal provides a basis
for human-machine interface (HMI) feedback. Otherwise, the vehicle
control unit returns to operation 702, where velocity data is
sampled during an increase in a velocity rate for a vehicle, and
continues from that time with the further velocity data provided
during the velocity increase.
[0119] At operation 712, the vehicle control unit 200 announces the
near real-time feedback signal. As noted, the target velocity is
unknown. Accordingly, the feedback signal provides feedback while
accelerating as to the acceleration state-constant or variable.
[0120] Based on the signal, a vehicle operator receives an
indication that they are operation a vehicle 100 in an improved
fuel efficient mode by, at least in part, providing a constant
acceleration. When an engine control unit 240 (see FIG. 2) receives
the feedback signal, the engine control unit may act on the
feedback to affect throttle, transmission, and other power train
systems to remain within a constant acceleration mode of operation
(or economy mode of operation generally).
[0121] Also, the near real-time feedback signal may be announced
via a visual indicator signal, such as a vehicle control panel,
head unit device, instrument cluster, via a haptic indication
signal (that is, vibration), such as a vehicle control surface,
seat, handheld mobile device, etc., and also via an audible
indication signal from various speaker units or chimes of the
vehicle, as well as through personal devices such as a handheld
mobile device. As may be appreciated, the vehicle control unit may
communicate using wireless transmissions, either in the context of
near field, or generally, such as under 4G/LTE technologies, as
discussed in detail with reference to FIG. 2.
[0122] While particular combinations of various functions and
features of the present invention have been expressly described
herein, other combinations of these features and functions are
possible that are not limited by the particular examples disclosed
herein are expressly incorporated within the scope of the present
invention.
[0123] As one of ordinary skill in the art may appreciate, the term
"substantially" or "approximately," as may be used herein, provides
an industry-accepted tolerance to its corresponding term and/or
relativity between items. Such an industry-accepted tolerance
ranges from less than one percent to twenty percent and corresponds
to, but is not limited to, component values, integrated circuit
process variations, temperature variations, rise and fall times,
and/or thermal noise. Such relativity between items range from a
difference of a few percent to magnitude differences. As one of
ordinary skill in the art may further appreciate, the term
"coupled," as may be used herein, includes direct coupling and
indirect coupling via another component, element, circuit, or
module where, for indirect coupling, the intervening component,
element, circuit, or module does not modify the information of a
signal but may adjust its current level, voltage level, and/or
power level. As one of ordinary skill in the art will also
appreciate, inferred coupling (that is, where one element is
coupled to another element by inference) includes direct and
indirect coupling between two elements in the same manner as
"coupled." As one of ordinary skill in the art will further
appreciate, the term "compares favorably," as may be used herein,
indicates that a comparison between two or more elements, items,
signals, et cetera, provides a desired relationship.
[0124] As the term "module" may be used in the description of the
drawings, a module includes a functional block that is implemented
in hardware, software, and/or firmware that performs one or more
functions such as the processing of an input signal to produce an
output signal. As used herein, a module may contain submodules that
themselves are modules.
[0125] Thus, there has been described herein an apparatus and
method, as well as several embodiments, for implementing a method
in a vehicle control unit for improving a fuel efficiency of a
vehicle, by providing a feedback relating to a constant
acceleration of the vehicle from a first velocity to a second
velocity.
[0126] The foregoing description relates to what are presently
considered to be the most practical embodiments. It is to be
understood, however, that the disclosure is not to be limited to
these embodiments but, on the contrary, is intended to cover
various modifications and equivalent arrangements included within
the spirit and scope of the appended claims, which scope is to be
accorded the broadest interpretations so as to encompass all such
modifications and equivalent structures as is permitted under the
law.
* * * * *