U.S. patent application number 09/272878 was filed with the patent office on 2001-08-09 for integrated message display system for a vehicle.
Invention is credited to BISHEL, RICHARD A., BRANDT, PETER CHARLES, GHITEA, NICOLAE JR., KIRN, CHRIS, MENIG, PAUL M., POWELL, JARED A., RENNER, DR. GOETZ.
Application Number | 20010012976 09/272878 |
Document ID | / |
Family ID | 26820242 |
Filed Date | 2001-08-09 |
United States Patent
Application |
20010012976 |
Kind Code |
A1 |
MENIG, PAUL M. ; et
al. |
August 9, 2001 |
INTEGRATED MESSAGE DISPLAY SYSTEM FOR A VEHICLE
Abstract
An integrated message system for a vehicle provides an
extendable, prioritized message scheme. Using this scheme, the
message system acts as a centralized message provider for variety
of alerts and operating data originating throughout the vehicle.
The message system defines a hierarchy of message levels, each
having a unique output protocol. The protocol defines attributes
associated with messages at a particular level such as textual or
graphical message, an auditory alert, as well as the scheme for
playing these messages and alerts. The system integrates a variety
of subsystems that conventionally have separate driver interfaces
such as a collision warning system and an adaptive cruise control
system.
Inventors: |
MENIG, PAUL M.; (TIGARD,
OR) ; BISHEL, RICHARD A.; (BEAVERTON, OR) ;
RENNER, DR. GOETZ; (ESSLINGEN, DE) ; GHITEA, NICOLAE
JR.; (TIGARD, OR) ; KIRN, CHRIS; (PORTLAND,
OR) ; POWELL, JARED A.; (PORTLAND, OR) ;
BRANDT, PETER CHARLES; (LAKE OSWEGO, OR) |
Correspondence
Address: |
KLARQUIST SPARKMAN CAMPBELL LEIGH
AND WHINSTON
ONE WORLD TRADE CENTER SUITE 1600
121 SW SALMON STREET
PORTLAND
OR
972042988
|
Family ID: |
26820242 |
Appl. No.: |
09/272878 |
Filed: |
March 18, 1999 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
60122167 |
Feb 26, 1999 |
|
|
|
Current U.S.
Class: |
701/1 ; 340/435;
701/31.4 |
Current CPC
Class: |
B60K 35/00 20130101;
B60K 2370/179 20190501; Y10S 707/99931 20130101; B60K 2370/195
20190501 |
Class at
Publication: |
701/1 ; 701/29;
340/435 |
International
Class: |
G05D 001/00 |
Claims
We claim:
1. An integrated message system for a vehicle comprising: two or
more electronic control units; an instrumentation control unit in
communication with the one or more electronic control units, the
instrumentation control unit including a visual display for
displaying vehicle messages and an audio transducer for generating
auditory signals; wherein the instrumentation control unit displays
a default screen and selectively overrides the default screen with
prioritized vehicle messages in response to predetermined events
detected in the electronic control units; wherein the prioritized
vehicle messages are organized into levels of importance such that
messages from a more important level override messages from a less
important level, and each level is associated with a different
visual display protocol and a different corresponding auditory
signal.
2. The system of claim 1 wherein each visual display protocol
defines a predetermined display duration and repeat cycle defining
when and how long the visual display associated with a prioritized
message overrides the default screen.
3. The system of claim I wherein the instrumentation control unit
is in communication with an input device that enables an operator
to acknowledge a prioritized message, and the instrumentation
control unit modifies the prioritized message to indicate that the
message has been acknowledged.
4. The system of claim I wherein the instrumentation control unit
displays a visual message indicating the importance level of a
prioritized message along with descriptive text describing event
specific information about the event that triggered the message for
each of the prioritized messages.
5. The system of claim 1 wherein the default screen is driver
selectable via an input device in communication with the
instrumentation control unit.
6. The system of claim 1 wherein the default screen displays
operating information about the vehicle including a fuel economy
indicator, or an odometer reading.
7. The system of claim 1 wherein each level of prioritized message
is associated with a different auditory tone indicating relative
importance of the level relative to the other levels of
messages.
8. The system of claim 7 wherein each level is associated with a
different sequence of beeping tones indicating relative importance
of the level relative to the other levels.
9. The system of claim 1 wherein each level is associated with a
different visual coding for flashing the corresponding visual
display to indicate relative importance of the level relative to
other levels.
10. The system of claim 1 including a collision warning electronic
control unit, and the collision warning electronic control unit
communicates collision detection events to the instrumentation
control unit, where the events are associated with the different
levels of prioritized messages depending on relative importance of
each collision detection event.
11. The system of claim 10 wherein collision detection events are
associated with a subset of the levels, and each level in the
subset is associated with a different visual display that indicates
relative importance of a collision warning with respect to the
other levels.
12. The system of claim 11 wherein the visual display for each
level of collision warning is associated with a graphical warning
symbol that grows progressively larger to reflect progressively
more dangerous collision warning conditions.
13. The system of claim 1 including an electronic control unit for
controlling adaptive cruise control, and the instrumentation
control unit displays visual messages associated with adaptive
cruise control events.
14. The system of claim 13 wherein adaptive cruise control events
are associated with different levels of prioritized messages
depending on relative importance of each adaptive cruise control
event.
15. The system of claim 14 wherein the adaptive cruise control
events include an operator input for setting a headway
parameter.
16. The system of claim 14 wherein the adaptive cruise control
events include an operator input for setting a vehicle set speed
parameter.
17. The system of claim 1 including a transmission electronic
control unit, and the instrumentation control unit displays visual
messages indicating a selected gear.
18. The system of claim 17 wherein the instrumentation control unit
displays visual messages indicating a selected driving mode.
19. A method for providing an integrated audio-visual message
system for a vehicle comprising: receiving messages regarding
predetermined events detected in one or more electronic control
units; displaying a default screen and selectively overriding the
default screen with prioritized messages in response to
predetermined events detected in the electronic control units;
wherein the prioritized messages are organized into levels of
importance such that messages from a more important level override
alerts from a less important level, and each level is associated
with a different visual display protocol and a different
corresponding auditory message.
20. An integrated audio-visual message system for a vehicle
comprising: two or more electronic control units; an
instrumentation control unit in communication with the two or more
electronic control units, the instrumentation control unit
including a visual display for displaying alphanumeric alerts and
an audio transducer for generating auditory alerts; wherein the
instrumentation control unit displays a default screen and
selectively overrides the default screen with prioritized alerts in
response to predetermined events detected in the electronic control
units; wherein the prioritized alerts are organized into levels of
importance such that alerts from a more important level override
alerts from a less important level, and each level is associated
with a different visual display protocol and a different
corresponding auditory alert.
Description
RELATED APPLICATION DATA
[0001] This application claims priority to co-pending U.S. patent
application Ser. No. 60/122,167, filed Feb. 26, 1999, entitled,
"Integrated Message Display System for a Vehicle", by Paul Menig,
Richard Bishel, Nick Ghitea, Chris Kim, Jared Powell, and Peter C.
Brandt, which is hereby incorporated by reference.
TECHNICAL FIELD
[0002] The invention relates to audio-visual message displays for
vehicles that provide operating, diagnostic, and warning
information to the driver.
BACKGROUND
[0003] Over the past several years, a variety of vehicle
electronics products have been developed to assist drivers, and
provide vehicle operating, trip and diagnostic information. This is
particularly true in long-haul trucks, where a number of options
are available such as collision warning systems, adaptive cruise
control, and wireless communication systems. Some collision warning
systems use radar to apprise the driver of collision dangers.
Adaptive cruise control is an advanced feature of collision warning
systems that uses radar and the vehicle's cruise control system to
maintain a desired following distance (called "headway"). In
addition to these new electronics products, existing components now
typically include electronic controls that can provide additional
vehicle diagnostic and operating data.
[0004] While these electronic products can provide useful
information to the driver, they can also overload the driver with
information. Even with careful design of displays and indicator
lights for each new feature, the driver can easily become
overwhelmed by the displays associated with these new products. As
such, the driver may ignore, or worse, become distracted by the
displays.
SUMMARY OF THE INVENTION
[0005] The invention provides an audio-visual message system for a
vehicle that receives information about operating conditions from a
variety of sources throughout the vehicle and generates visual and
auditory outputs via a centralized message center. The system
includes an instrumentation control unit that manages the output of
alerts through a visual display and audio transducer. The
instrumentation control unit receives information about operating
conditions from other electronic control units in the vehicle. In
response, the instrumentation control unit determines the
appropriate messages to generate based on a general, extendable
prioritization scheme.
[0006] The system prioritizes alerts based on their relative
importance. It organizes alerts into levels of importance, where
each level has a corresponding visual and auditory alert that
distinguishes it from other levels. When an event is detected that
triggers an alert, the instrumentation control unit overrides a
default screen and plays the corresponding alert. When more than
one alert is activated, the instrumentation control unit resolves
conflicts based on the priority of each alert.
[0007] Another aspect of the invention is the integration of
collision warning messages into the system's message scheme. A
collision warning system communicates collision warning conditions
to the instrumentation control unit. The instrumentation control
unit determines whether to override the current message with a
collision warning alert based on the relative priority of the alert
and the current message. The collision warning alerts use a
combination of visual and auditory warnings that grow progressively
more intense as the degree of danger of a collision danger
increases. This approach eases the driver's workload because the
collision alerts are integrated into the instrumentation control
unit's message center, which provides a centralized source of
information to the driver.
[0008] Yet another aspect of the invention is the integration of
adaptive cruise control messages into the system's centralized
message scheme. The instrumentation control unit prioritizes
adaptive cruise control messages in a similar manner as collision
warning messages. In particular, it determines whether to override
the current message based on the relative priority of the current
message and a new adaptive cruise control message. In one
implementation, for example, the instrumentation control unit
manages the display of three types of adaptive cruise control
messages: function set messages, system failure messages, and
danger ahead messages. It generates function set messages in
response to user input, such as when the driver sets a desired
headway for the adaptive cruise control system. It generates system
failure messages in response to detecting a failure of some aspect
of the adaptive cruise control system. Finally, it generates danger
ahead messages in response to collision warning events that occur
while the vehicle is adaptive cruise control mode.
[0009] Another aspect of the invention is the integration of
transmission messages into the system's centralized message scheme.
The instrumentation control unit integrates the display of
transmission messages, such as the current gear and mode of the
transmission, by displaying this information along with the display
of a default screen or an alert screen.
[0010] Further features of the invention will become apparent with
reference to the following detailed description and accompanying
drawings
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a block diagram illustrating an implementation of
electronic subsystems and their interconnection with an
instrumentation control unit.
[0012] FIG. 2 is a diagram illustrating the instrumentation control
unit in FIG. 1.
[0013] FIG. 3 is a diagram illustrating a vehicle dash, and the
positioning of the instrumentation control unit's display on the
dash.
[0014] FIG. 4 is a diagram illustrating the keypad for the
instrumentation control unit.
[0015] FIGS. 5-7 are diagrams illustrating the operation of four
levels of prioritized message displays. FIG. 5 illustrates the
operation of the highest priority alert, a DANGER alert. FIG. 6
illustrates the operation of the next highest priority alert, a
WARNING alert. FIG. 7 illustrates the operation of the next highest
priority alert, a CAUTION alert. Finally, FIG. 8 illustrates the
operation of the lowest priority alert, a NOTE alert.
[0016] FIG. 9 is a diagram illustrating message displays of
collision detection warnings integrated into the message center of
the instrumentation control unit shown in FIGS. 1 and 3.
[0017] FIG. 10 is a table illustrating a list of collision
detection display messages and their corresponding priority and
data bus message format.
[0018] FIG. 11 is a diagram illustrating screens in the message
center for identifying the driver to the system for the purpose of
maintaining a driver specific data record of operating events,
including collision detection events.
[0019] FIG. 12 is a diagram illustrating screens in the message
center for reporting adaptive cruise control information.
[0020] FIG. 13 is a diagram illustrating how transmission
information is integrated into the message center.
DETAILED DESCRIPTION OF THE INVENTION
[0021] System Implementation Overview
[0022] FIG. 1 is a block diagram illustrating the system
architecture of electronic control units in an implementation
installed in a truck. The system architecture includes a number of
electronic control units (ECUs, 100-110) interconnected via data
links 112, 114. An instrumentation control unit (ICU) 100 located
in the dash of the vehicle provides an integrated message center
for other subsystems in the vehicle, including the engine ECU 102,
transmission ECU 104, anti-lock brake ECU 106, and collision
warning ECU 108. In addition, the system includes a data logging
unit 116, which monitors messages communicated over the data link
and records operating data in response to detecting events.
[0023] The integrated message center of the ICU 100 in FIG. 1
includes a visual display 118 and audio transducer (i.e., a
speaker) 120 for generating audio-visual alerts. The visual display
includes a display screen 122 as well as indicator lights (e.g.,
124a-c). The driver can enter input to the ICU via an input device
126 (e.g., a keypad) and, in some implementations, via discrete
switches 128 (e.g., rocker switches, push buttons). Switches and
other dash controls that impact the operation of the ICU may be
wired to the ICU or to other ECUs, or both. For example, a
collision warning system and/or adaptive cruise control system may
include input switches located on the dash. These switches can be
wired directly to the collision warning ECU 108, which in turn
communicates input from the switches to the ICU. Conversely, other
switches may be wired directly to the ICU, which in turn,
communicates input from the switches to another ECU via the data
link 114.
[0024] The engine ECU 100 shown in FIG. 1, controls and monitors
the operation of the engine. Like the other ECUs, the engine ECU
includes a programmed data processor and memory for storing
computer programs and data. The data processor executes routines
stored in the memory to control and monitor engine performance.
[0025] The engine ECU also includes a variety of sensors and
controls used to monitor and control the engine. One important
function of the engine ECU is the control of the throttle. The
engine ECU controls the fuel rate by issuing control signals to a
fuel injector that controls the flow of fuel to the engine's
cylinders.
[0026] The ECU includes several sensors that monitor vehicle
operating data, including a speed sensor, an RPM sensor, a throttle
position sensor and a cruise status sensor. Some vehicle operating
parameters are computed from measured data. For example, the engine
torque is computed using a mathematical formula that expresses
engine torque as a function of measured parameters, including fuel
rate and turbo boost pressure.
[0027] The engine ECU determines the amount of fuel supplied to the
cylinders in the engine by controlling the solenoid valves that
inject fuel to the engine cylinders. The rate of fuel flow is
directly related to the amount of time that the solenoid valve is
closed. This time period determines the volume of fuel injected
into a cylinder per revolution. By determining the amount of time
that the solenoid valves are closed, the engine ECU can compute the
amount of fuel consumed by the engine. The engine ECU calculates
the fuel flow rate from the dwell of the injection pulse and the
engine speed.
[0028] The engine ECU measures the vehicle's road speed. A speed
control senses the speed of rotation of the tail shaft of the truck
and converts it into road speed. A hall effect sensor located on
the tail shaft generates an analog signal comprised of a series of
pulses representing the rotation rate of the engine. The engine ECU
is programmed to read this digital value and derive the
instantaneous speed in miles per hour.
[0029] The engine ECU also monitors a variety of other vehicle
operating parameters, including RPM, engine torque and throttle
position. These parameters are transferred to the ICU 100 over the
data link 114.
[0030] The transmission ECU 104 controls the truck's transmission.
The specific type of ECU varies depending on the transmission
vendor, and the type of transmission, e.g., manual, automatic or
automated mechanical transmission. Examples of transmission systems
that are controlled via ECUs include the Eaton Fuller
AutoShift.RTM. heavy-duty automated truck transmission and the
Meritor SureShift.TM. transmission system.
[0031] The transmission ECU receives driver instructions via a
driver interface in the cabin of the truck. One possible
implementation of the driver interface is a column mounted shift
control 150 that communicates shift command inputs to a
transmission ECU. For more information on this type of driver
interface, see co-pending patent application Ser. No. 09/258,649,
entitled "Lever Assembly for an Electronically Controllable Vehicle
Transmission", filed Feb. 26, 1999, by Paul Menig, Michael von
Mayenburg, Nasser Zamani, Joseph Loczi, and Jason Stanford, which
is hereby incorporated by reference.
[0032] The anti-lock brake ECU 106 controls the anti-lock brakes on
the truck. Examples of anti-lock brake systems controlled via an
ECU include the WABCO ABS from Meritor WABCO Vehicle Control
Systems, Bendix AntiLock Systems from Allied Signal Truck Brake
Systems Company, and Bosch AntiLock Brake Systems.
[0033] The collision warning ECU 108 controls a collision warning
system on the truck. The collision warning system (CWS) includes a
front sensor 140, side sensor 142, side sensor display 144, and
switches 128 (e.g., an ON/OFF switch, volume control, and collision
warning range/adaptive cruise headway control). A programmed CPU on
the CWS ECU 108 receives information about nearby objects from the
front sensor 140 and side sensor 142, computes collision warning
conditions, and communicates warnings to the ICU 100. Based on
information from the front sensor 140, the CWS ECU 108 measures the
range, distance, closing speed, and relative speed to vehicles and
other objects in its field of view. For radar-controlled systems,
the front sensor 140 is a radar antenna. Other types of sensors may
be used as well, such as infra-red sensors. Side sensors 142
located on the side of the truck detect vehicles in the driver's
blind spots. In response to detecting an object via the side
sensor, the CWS generates a warning indicator on the side sensor
display 144.
[0034] In addition to providing collision warnings, the CWS ECU 108
operates in conjunction with the engine ECU 102, anti-lock brake
ECU 106 and engine brake ECU 110 to provide Adaptive Cruise Control
(ACC). Adaptive cruise control is an application of the collision
detection system that uses data detected from the front sensor to
maintain headway (i.e., the following distance) between the truck
and the vehicle in front of it. The ACC system adjusts the
vehicle's speed from the "set speed" established for cruise control
to maintain a safe following distance from a slower vehicle. To
control vehicle speed, the ACC system sends control messages via
the J1939 data link to: 1) the engine ECU for throttle control, 2)
the engine brake to actuate engine retarder braking, 3) the
anti-lock brake system to initiate automatic braking, and 4) the
transmission control to downshift the transmission. When the slower
vehicle increases its speed or changes lanes, the ACC resumes the
speed to return to the desired set speed. For more information on
adaptive cruise control, see U.S. Pat. No. 5,839,534, entitled
"System and Method for Intelligent Cruise Control Using Standard
Engine Control Modes," which is hereby incorporated by
reference.
[0035] The CWS ECU 108 in the current implementation is part of the
EVT-300 collision warning system from Eaton VORAD Technologies,
L.L.C. of San Diego, Calif. The ACC functionality is part of the
SMARTCRUISE.RTM. adaptive cruise control system from Eaton VORAD
Technologies. Other collision warning and adaptive cruise control
systems may be used in the alternative. One example of an
alternative system is the A.D.C. distance control system from
A.D.C. ADC adaptive cruise control systems include radar based
sensors and infrared based sensors.
[0036] The engine brake ECU controls engine braking by controlling
the discharge of gases from the engine's cylinders. While shown as
a functionally separate unit, the engine brake ECU is typically
incorporated into the engine ECU.
[0037] The Data Links
[0038] The implementation shown in FIG. 1 uses two separate data
links 112, 114: 1) a data link 114 designed according to SAE J1708,
a standard for serial data communication between microcomputer
systems in heavy duty vehicle applications; and 2) a data link 112
designed according to the SAE J1939 Serial Control and
Communication Vehicle Network standard. While the current
implementation primarily uses the J1708 data link as a shared
communication path between the ICU and the other ECUs, it also uses
dedicated wiring connections directly between some ECUs and sensors
to convey information to the ICU. For alternative implementations,
it may also use the J1939 data link to connect the ICU with other
ECUs.
[0039] The J1708 data link is comprised of a twisted pair cable
operating at 9600 baud. The data link forms a communication channel
among the electronic control units coupled to it. Electronic
control units generate a digital signal on the data link by
applying a voltage differential between the two wires in the cable.
A voltage differential above a specified threshold represents a
logic high value, while a voltage threshold below a specified
threshold represents a logic low value. This type of data link is
particularly advantageous for hostile environments because the
signal is more robust and impervious to signal degradation.
[0040] The ECUs connected on the network communicate with each
other according to protocols defined in SAE J1708 and SAE J1587.
The SAE J1587 standard is entitled "Joint SAE/TMC Electronic Data
Interchange Between Microcomputer Systems and Heavy Duty Vehicle
Applications." This standard defines one format for data and
messages communicated among microprocessors connected to a shared
data link, and is specifically adapted for use with SAE J1708.
[0041] According to SAE J1708/J1587, the ECUs on the data link
communicate by passing messages to each other. The ECUs can be
either receivers, or receivers and transmitters. In this particular
implementation, the instrumentation control unit 100 is both a
transmitter and receiver. The engine ECU acts as both a transmitter
and receiver as well. As a transmitter, it sends messages to the
ICU regarding road speed, fuel rate, engine torque, RPM, throttle
position, engine status, etc. It receives messages regarding cruise
control functions.
[0042] In the J1587 format, a message includes the following: 1) a
module ID (MID), 2) one or more parameters, and 3) a checksum. The
number of parameters in a message is limited by the total message
length defined in the SAE J1708 standard. The message
identification numbers are assigned to transmitter categories as
identified in SAE J1587. The MID portion of a message specifies the
origin or transmitter of the message. In the majority of cases,
messages are broadcast on the data link without specifying a
receiver. However, the message format can be extended to include
the MID of a receiver after the MID of the transmitter for special
applications.
[0043] The messages passed among the ECUs convey information about
one or more parameters contained within the messages. According to
the SAE J1587 standard, the first character of every parameter is a
parameter identification character (PID). The parameter identified
by the PID directly follows the PID. The SAE J1587 supports
different data formats including a single character, a double data
character or more than two data characters representing the
parameter data. Several parameters can be packed into a message,
limited by the maximum message size as noted above.
[0044] Again, in this implementation, the ECUs communicate with
each other over one of the data links 114 according to the SAE
standard J1708. The standard describes methods for accessing the
data link and constructing messages for transfer over it. It also
defines a method for resource contention among the ECUs on the data
link.
[0045] An ECU wishing to transmit data on the data link first waits
for a lull in transmission of data on the data link. In this
particular implementation, the length of the lull is 200
milliseconds. After detecting this lull, the ECU attempts to
transmit its message. The transmitter broadcasts its message onto
the data link. Each of the ECUs that operate as receivers on the
data link will receive the message. However, receivers only act on
a message if programmed to do so.
[0046] In some cases two or more transmitters may attempt to
broadcast a message at one time, giving rise to a collision. To
resolve a conflict among transmitters, messages have a priority
according to their message identifiers. The MIDs of higher priority
transmitters have a greater number of bits set at a logic level
one. When more than one message is broadcast at a time, the more
dominant message takes priority over lesser dominant messages.
Since a lower priority message is blocked by a higher priority
message, the transmitter of the lower priority message must wait
and retransmit the message after another lull An ECU on the data
link will continue to attempt to send a message until it is
successfully broadcast to the data link.
[0047] The Instrumentation Control Unit
[0048] FIG. 2 is a functional block diagram illustrating the
architecture of the ICU 200 shown in FIG. 1. The ICU has a CPU 202,
memory 204 and a port interface 206 for connecting the unit to the
J1708 data link 208. The memory 204 includes programmable ROM
(EEPROM) 210, RAM 212 and permanent ROM 214. The routines for
controlling the ICU are stored in ROM 210, while re-configurable
data is stored in the EEPROM 214.
[0049] In one specific implementation, the ICU has a 68HC16
microprocessor from Motorola Corporation, and its memory
configuration 204 includes EEPROM, ROM, and RAM. This specific ICU
has 8 KB of external EEPROM, 500K of ROM and 64K of RAM. The
internal memory of the ICU includes 1Mbyte of RAM and 1Mbyte of
ROM. These specifications are unique to the implementation, but
will vary from one implementation to the next. A variety of
microprocessors and memory systems can be used to implement the
functionality of the instrumentation control unit. Preferably, the
processor used in the ICU should have at least a 16 bit
microprocessor. The speed of the processor can vary, but should be
sufficient to manage the message center functions described below
within a 200 ms time increment.
[0050] The ICU also includes an input device 220 and a display
device 222. In the current implementation, the input device is a
ten-key keypad. The display device 222 provides a textual and
graphical output to the driver. The current implementation of the
display device is a two by 20 vacuum fluorescent display.
[0051] The ICU used in this implementation is manufactured by
Joseph Pollak of Boston, Mass. for Freightliner Corporation, and is
available as a replacement part from Freightliner Corporation.
[0052] Example of the Dash Layout
[0053] FIG. 3 is a diagram illustrating the position of the ICU's
display 346 and an input device 344 among the instruments and
controls on a dash 322 in one implementation. The dash 322 shown in
FIG. 3 includes a number of gauges, including for example, an
analog speedometer 324 and tachometer 326, a fuel gauge 328, etc.
Instruments located at the dash include a parking brake switches
330, 332, heating, ventilation, and air conditioning (HVAC)
controls 334-340, etc.
[0054] In addition to these discrete gauges, instruments and
indicator lights, the dash also includes the user interface for the
control unit, which is referred to as the instrument control unit
in this implementation. The user interface of the instrument
control unit includes a display device 342 and an input device 344,
both located on the dash.
[0055] The display device 346, in the current implementation, is a
two by 20 vacuum fluorescent display. Alternative implementations
are also possible such as a Liquid Crystal Display (LCD) or raster
display device. The input device 344 of the ICU is a keypad
including dedicated and general purpose function keys. Alternative
implementations and configurations of the input device are also
possible.
[0056] FIG. 4 is a diagram of one implementation of the keypad. The
keypad includes a number of keys to enable the driver to query the
ICU for information and to control its operation. The keypad of
FIG. 4 includes the following dedicated keys:
1 1. Temperature (402) 2. Fuel (404) 3. Trip (Miles, hours and
fuel) (406) 4. Leg (Miles, hours and fuel) (408)
[0057] The dedicated keys are used to request specific information
such as the current outside air temperature (temperature 402), fuel
efficiency information 404 (e.g., fuel used in gallons and average
MPG), etc. The trip and leg keys 406, 408 are used to display the
miles traveled, elapsed hours, and fuel consumed for a trip or a
leg of a trip.
[0058] The keypad also includes the following general-purpose
keys:
2 1. Left Arrow Key (410) 2. Down Arrow Key (412) 3. Right Arrow
Key (414) 4. Set/Reset Key (416) 5. Event Key (418)
[0059] These keys can be used to scroll through message screens on
the display, enter data, clear messages, etc. For example, these
keys can be used to enter configuration data such as the volume
object detection range for collision warnings, and the set speed
and headway for adaptive cruise control.
[0060] The event key enables the driver to log an event. In
response to this event, data logging unit 116 in the system
persistently stores performance and ECU fault data from the data
link occurring during a time period starting a predetermined time
before and after the event. For more information on this data
logging function see U.S. Pat. No. 5,802,545, which is hereby
incorporated by reference.
[0061] Finally, the keypad includes an acknowledgment key 420. When
the ICU generates a warning message, the driver can use the
acknowledgment key to indicate that he/she acknowledges the
warning. The ICU responds differently to this key depending on the
type and state of the warning condition, as explained in more
detail below.
[0062] General Vehicle Operating Information and Message
Prioritization
[0063] During normal operation of the truck, the ICU displays
vehicle operating information, including a bargraph illustrating
the rate of change of fuel economy and the short term average fuel
economy, and an odometer reading. For more information, see U.S.
Pat. No. 5,693,876 and co-pending patent application Ser. No.
08/982,117 entitled, "Fuel Use Efficiency System For A Vehicle For
Assisting The Driver To Improve Fuel Economy," which are hereby
incorporated by reference. The driver can directly access other
information via the trip, fuel, leg, and temp input keys as
explained above.
[0064] In addition, the ICU displays a variety of "priority
overwrite" screens that override the normal operating screens when
certain operating conditions are detected.
[0065] These operating conditions include, for example, park brake
on (while vehicle is moving), high coolant temperature, low oil
pressure, air filter clog, turn signal on, etc. The ICU generates
and controls the display of these overwrite screens according to a
prioritization scheme. In the current implementation, for example,
there are four levels of alerts: Level 1 "Danger", Level 2
"Warning", Level 3 "Caution", and Level 4 "Note" or "Message." A
Level 1 warning is a message intended to evoke an immediate
reaction from the driver and is used for extremely serious
problems. A Level 2 warning indicates a very serious problem and
also requires immediate reaction from the driver.
[0066] Level 3 warnings indicate a serious problem and require
action soon. Level 4 warnings consist of status information and are
intended to require action only when convenient. The driver can
acknowledge an alert by pressing the acknowledgement key in the
keypad of the ICU.
[0067] Each of the four levels of alert is associated with a
predetermined message protocol, including a visual and audio
indicator. The following table provides an example of the message
protocols associated with the four warning levels. When a priority
overwrite message is activated, the ICU displays a flashing message
and emits a sequence of beeps according to the following
protocols.
3TABLE 1 AUDITORY CODING Pause VISUAL between CODING Number Length
tones Frequency ON OFF LEVEL of tones (msec) (msec) of tones (msec)
(msec) DANGER 7 200 14 560/840 400 200 WARNING 4 200 70 560/840 400
350 CAUTION 2 200 140 560/840 400 500 NOTE 1 300 n/a 450 n/a n/a
MIS-USE 1 300 n/a 250 n/a n/a
[0068] A message from the ICU transitions through a series of
states, including "unacknowledged" and "acknowledged." In
particular, the message center initially generates a message, the
message is in an "unacknowledged" state, meaning that the ICU is
seeking a confirmation from the driver that he/she is aware of it.
To get the driver's attention, the ICU emphasizes the significance
of the message by flashing the text on the display and accompanying
the message with audible tones. When the driver presses the
acknowledgment key, the message center transitions to an
"acknowledged" state. A text message remains on the display until
the driver has an opportunity to read and acknowledge it a second
time by pressing the acknowledge key again.
[0069] The ICU is programmed so that the minimum time between the
first and second acknowledgement is long enough (e.g., 3-5 five
seconds) to prevent the driver from removing the message by
pressing the acknowledgement key rapidly in succession (e.g., a
quick double-click of the key) During this time, the
acknowledgement key is essentially deactivated to prevent the
driver from erasing a message without reading it. When the
acknowledgment key becomes active, the message center displays a
graphical symbol to inform the driver that he/she can press the
acknowledgement key to remove the message. In a case when the
driver presses the acknowledgement key before the acknowledge
symbol is displayed, the ICU emits an error beep to provide the
driver with feedback indicating that he/she acknowledged the
warning message too soon.
[0070] FIGS. 5-8 illustrate the operation of the danger, warning,
caution, and note message levels in the message center. When the
message center detects a level one condition, it displays the word
"DANGER" on the first line of the display and a text message
associated with the danger condition on the second line of the
display (e.g., STOP ENGINE QUICKLY) as shown in FIG. 5. Initially,
the ICU flashes the text message and generates beeping tones as
reflected by the graphic 500 at the top of FIG. 5. The graphical
symbol 502 indicates to the driver that he/she can disable the
flashing and beeping by pressing the acknowledgement key 504. In
response to actuation of the acknowledgment key, the message center
transitions to the state shown in the rectangular box 506 at the
bottom of FIG. 5. The box reflects that the message center is no
longer flashing or emitting beeping auditory tones. At the danger
level, the message center cycles between a flashing and beeping
message state 500 and a non-flashing display without beeping in
response to the acknowledgement key. The repeat time of the message
is a pre-determined parameter in the ICU that controls when the
message center repeats the "unacknowledged" state.
[0071] For level two conditions, the message center initially
generates a flashing and beeping warning message as reflected by
the graphic 600 at the top of FIG. 6, and transitions to three
other states before repeating. On the first line of the display,
the message center displays the word "WARNING" along with a symbol
of the acknowledgement key. On the second line, the message center
displays descriptive text associated with the level two condition,
such as LOW OIL PRESSURE as shown in FIG. 6.
[0072] In response to a first press of the acknowledgement key 602,
the message center transitions to a first "acknowledged" state
shown as a rectangular box 604 on the right side of FIG. 6. The
message center remains in this state for a predetermined delay
period (e.g., 3-5 seconds), and then transitions to a second state
shown in the rectangular box 606 at the bottom of FIG. 6. The only
difference between the first and second states is the presence of
the graphical symbol 608 indicating that the acknowledgement key is
active. This symbol informs the driver that pressing the
acknowledgement key another time will remove the message from the
display. In response to the driver pressing the acknowledgement key
610 a second time, the message center reverts to the driver
selectable default screen, as illustrated by the rectangular box
612 on the left-hand side of FIG. 6. If the level 2 condition still
persists, the message center repeats the message after a
predetermined period of time has elapsed (i.e. the repeat
time).
[0073] For level three conditions, the message center progresses
through similar states as in level two. However, as reflected by
graphic 700 at the top of FIG. 7, the initial message is less
intense in that the pause between the tones is longer. Initially,
the message center displays the word "CAUTION" on the first line of
the display along with the symbol 702 of the acknowledgement key.
On the second line of the display, the message center displays
descriptive text associated with the warning condition such as
"TURN SIGNAL ON." In response to the driver pressing the
acknowledgement key 704, the message center transitions to a first
state where the message is no longer flashing and beeping and the
acknowledgment symbol is no longer illuminated as shown in the
rectangular box 706 on the right side of FIG. 7. After a
pre-determined delay, the message center transitions to a second
state where the acknowledgement key is included on the display as
shown in the rectangular box 708 at the bottom of FIG. 7. In
response to the driver pressing the acknowledgement key 710 a
second time, the message center transitions to a driver selectable
default screen as shown by the rectangular box 712 on the left-hand
side of FIG. 7. The level 3 message will repeat after a
pre-determined period of time if the condition causing the message
is still active.
[0074] For level four conditions, the message center begins with a
flashing message and a single beep at a lower frequency than the
higher level warning messages. This initial state is represented by
the graphic 800 at the top of FIG. 8. On the first line of the
message display, the message center displays the word "NOTE" and on
the second line displays a text description of the warning
condition such as "LOW WIPER FLUID." After a pre-determined delay,
the message center transitions to a state 802 where the ICU adds a
graphical symbol of the acknowledgement key 804 to the display. In
response to the driver pressing the acknowledgement key 806, the
message center transitions to a driver selectable default screen as
shown by the rectangular box 808 on the left side of FIG. 8. The
message center then repeats after a pre-determined period of time
if the warning condition is still active.
[0075] The prioritization scheme implemented in the ICU enables it
to integrate several messages and warning indicators for a variety
of different electronic subsystems and sensors onboard the vehicle.
When the manufacturer wishes to add a new message, it assigns it a
priority level within the prioritization scheme. The ICU then
determines when and how to display the warning message relative to
other messages based on its priority and a set of priority
rules.
[0076] Table 2 below gives an example of the type of warning
messages that are integrated into the prioritization scheme.
4TABLE 2 LEVEL 1 LEVEL 2 LEVEL 3 LEVEL 4 DANGER WARNING CAUTION
RECIRC MODE PARK HIGH TURN ENGAGED BRAKE COOLANT SIGNAL STALE AIR
IN 20 OFF TEMP ON MIN. DANGER WARNING PROVIDE FRESH AIR INCOMING
PARK LOW OIL STOP RECIRC. MAX MESSAGE BRAKE PRESSURE A/C text ON
WARNING CAUTION LOW CHANGE AIR FILTER VOLTAGE WARNING AIR FILTER
CLOGGED
[0077] In the current implementation, the ICU is programmed to
adhere to the following priority rules. First, higher priorities
override lower priorities such that a danger condition has the
highest priority, followed by warning, caution, and finally
note/message. When more than one monitored condition is active at a
given time for messages of the same priority level, the most recent
message overrides the older message. Danger messages that occur
within the same detection period in the ICU alternate every second.
In the current implementation, the detection period is 200
milliseconds. The ICU manages warning messages that occur in the
same detection period by showing one warning or caution for at
least fifteen seconds and then switching to the second warning or
caution. Finally, the ICU displays messages that are received in
the same detection period sequentially.
[0078] Integration of Collision Warning System into the Message
Center
[0079] The ICU and its message center act as the driver interface
for the collision warning system. When the CWS detects a collision
warning condition, it communicates the condition to the ICU, which
in turn, generates the appropriate message from the message center,
which typically includes a visual and an accompanying auditory
warning. According to human factors studies, auditory signals are
the most dominant source of information to the driver. Therefore,
the auditory warnings associated with each collision warning
condition are selected to ensure that they are not confused with
other sounds in the vehicle, or masked by other sounds. In
addition, for quick and accurate interpretation of visual signals,
the message center provides the visual warnings associated with
each warning condition in the driver's line of sight (see, for
example, the position of the display on the dash in FIG. 3).
[0080] FIG. 9 is diagram illustrating an implementation of the
visual indicators for the collision warning system integrated into
the message center. The current implementation of the message
center displays five different visual indicators 900-908. As the
closing distance between the truck and the vehicle in front of it
decreases, the message center displays progressively stronger
visual warnings and generates corresponding auditory warnings. For
example, the top three visual indicators 900-904 shown in FIG. 9
illustrate the display screen of the message center for first,
second and third stage distance alerts from the collision warning
system. As the closing time between the truck and the obstacle
reaches predetermined values associated with each stage, the
message center displays a progressively larger triangle and the
words, "DANGER AHEAD." The message center also displays the large
triangle alert 904 in response to warning messages associated with
the detection of a stationary or slow moving object.
[0081] When the collision warning system detects an object within a
predetermined distance (e.g., 350 feet), but this object does not
represent a significant threat of collision, the message center
displays a small triangle 906 in the default screen 910 of the
message center. In other words, the visual indicator of the
detection does not overwrite the current default screen, but
instead is combined with it. In the example shown in FIG. 9, the
default screen displays the short term average fuel economy 912, a
bar graph representing changes in fuel economy 914, and the
odometer reading 916. This default screen is merely one example of
the type of normal operating condition data that may be displayed
with the object detection indicator 906. In an alternative
implementation, the visual indicator of a detected object may be
designed to overwrite the current default screen.
[0082] Another collision warning message integrated into the
message display is the creep alert (see screen 908, FIG. 9). The
message center displays the creep alert screen 908 when the
collision warning system detects a object less than a predetermined
distance ahead (e.g., 15 feet) and the truck is creeping (e.g., the
truck speed is less than 2 MPH).
[0083] In addition to integrating collision warnings into the
message center, the current implementation also integrates control
switches for the collision warning system into the dash of the
vehicle. FIG. 3 shows an example of these controls, which include a
volume control 350, an ON/OFF control 352 and range control 354.
The volume control allows the driver to adjust the volume of
auditory warnings, while the range control allows the driver to
control the range of the forward object sensor. Both the volume and
range controls are implemented with rocker switches in the current
implementation. The ON/OFF button is implemented with a back lit
push button.
[0084] In addition to the visual warnings illustrated in FIG. 9,
the message center generates auditory warnings as well. Tables 3A
and 3B below provide a brief summary of message protocol codings in
alternative implementations of the ICU.
5 TABLE 3A Auditory Coding Pause Tone Warning Number Length Between
Tones Frequency Visual No. Description of Tones (msec) (msec) of
Tones Coding 0 side detection 3 100 14 1400, 2000, red LED in 1600
right dash display 1 Stationary object 7 200 14 1800/1200 Large
Slow moving triangle in object ahead Message 1 Sec. Center plus
Following DANGER AHEAD Distance 2 2 Sec. 4 200 70 1800/1200 Medium
Following triangle in Distance Message Creep Alarm Center plus
DANGER AHEAD 3 3 Sec. 2 200 140 1800/1200 Small Following triangle
in Distance Message Center plus DANGER AHEAD
[0085]
6TABLE 3B Tone Pattern (Bold = active, Tone Non-bold = pause)
Frequency of Tones No. Description (in msec) (in Hz) 0 Side Sensor
Alert 96, 96, 32, 96, 96 2000, 2400, 0, ID Read Pass 2400, 2000 1 1
sec. 80, 80, 80, 80 1800, 600, 1800, following distance 600 2 2
sec. 80, 80 1800, 600 following distance 3 Proximity Alert 64, 64,
80, 64, 64 800, 400, 0, 800, 4 Volume Change 48 400, 600 5 Download
Success 300, 100, 300 450, 0, 450 Accident Reconstruction Freeze
Confirmation 6 Built-in Self-Test 300 250 Failure No Driver ID
Download Fail Accident Reconstruction Freeze Failure ID Read Full
Low Voltage
[0086] Table 4 provides a more detailed description of an
integration of features of the collision warning system into the
message center (M.C.) and dash display.
7TABLE 4 Integrated Format Display Feature Auditory Visual
Control/Sensing Unit Power-On None light on switch illuminates when
Rocker switch Drivers Card Status system is on (M.C. NOTE if card
is not inserted) Volume Control 1 short tone for each change M.C.
display Rocker switch (default setting = 3/4 increment (at the new
RADAR VOL 75% maximum volume) volume level) (displayed for 7
seconds after each change) Speaker all auditory output n/a adjusted
by volume control Range 1 short tone for each {fraction (1/10)}
M.C. display: Rocker switch dash or steering control/accident
second change in range MAX RADAR RANGE 2.5 wheel (default setting
at maximum recorder setting SECONDS range) (gives current maximum
range setting based on following distance) System failure M.C.
tones for warning TELLTALE: RADAR FAIL (red) System check sensor
(performed M.C. message: every 15 seconds during normal WARNING
RADAR SYSTEM operation) FAILURE Adjustments in n/a n/a Message
Center is automatically Lighting dimmed Vehicle detection none very
small triangle on default object detected within 350 feet screen of
M.C. and/or detect indicator light 1.sup.st stage See tone No. 3,
Table 3A DANGER AHEAD 3 second sensor distance alert small triangle
(figure below) 2.sup.nd stage See tone No. 2, Table 3A DANGER AHEAD
2 second sensor distance alert medium triangle (figure below)
3.sup.rd stage See tone No. 1, Table 3A DANGER AHEAD 1 second
sensor distance alert large triangle (figure below) Stationary
object See tone No. 1, Table 3A DANGER AHEAD Should be set for a
distance large triangle appropriate to speed of vehicle (to (figure
below) reduce false alarms) Slow moving object See tone No. 1,
Table 3A DANGER AHEAD Should be set for a distance large triangle
appropriate to speed of vehicle (to (figure below) reduce false
alarms) Creep alarm See tone No. 2, Table 3A CREEP ALERT Vehicle
speed <2 mph & object less row of small triangles than 15
feet ahead (figure below) No vehicle detected none yellow light on
dash display Stays on when no vehicle is detected in blind spot by
the blind spot sensor Vehicle detected in See tone No. 0, Table 3A
red light on dash display Activated when objects are detected blind
spot by the blind spot sensor
[0087] As explained above, the message center integrates messages
from a variety of different vehicle systems using a prioritization
scheme. It also uses a prioritization scheme to integrate the
messages from the collision warning system. In the current
implementation, the priority rules for integrating collision
warning messages are as follows. The warning messages for a
stationary object, slow moving object, and the shortest monitored
following distance (one second) are assigned the highest priority
and override level 1 danger alerts. As such, the immediate external
threat takes precedence over in-vehicle dangers. The level 1 danger
alerts have the next highest priority and override collision
warning alerts for following distances of two and three seconds and
the creep alarm. The rational for ranking level 1 danger alerts
ahead of these collision alerts is that severe in-vehicle dangers
take precedence over less immediate external threats. Level two
warning messages and level three caution messages may override
collision warnings for two and three second following distances if
those collision warnings have been displayed for at least fifteen
seconds. The rational is that the driver has most probably chosen a
particular distance to the vehicle ahead and intends not to change
the following distance. In this case, the driver is aware of the
situation and a level two or level three message override the
collision warning conditions.
[0088] A summary of the priority assignments for the message center
and collision detection warnings is provided below in Table 5. Note
that Table 5 represents only an example of one possible
implementation. Alternative codings are possible, such as the
auditory codings shown in Table 3B.
8TABLE 5 Overview of Priority Assignments and Auditory Signals for
Message Center Pause Priority Warning Number Length Between Tones
Frequency Level Description of Tones (msec) (msec) of Tones 1
Stationary Object 7 200 14 1800/1200 Slow Moving Object 1 Sec.
Following Distance 2 Message Center: 7 200 14 560/840 DANGER 3 2
Sec. Following Distance 4 200 70 1800/1200 Creep Alarm 4 3 Sec.
Following Distance 2 200 140 1800/1200 5 Message Center: 4 200 70
560/840 WARNING 6 Message Center: 2 200 140 560/840 CAUTION 7
Message Center: 1 300 n/a 450 NOTE/MESSAGE independent Side Object
Detection (may 3 100 14 2400, 2000, level be given with any other
1600 warning) Message Center: "Key 1 300 n/a 250 press not
available" or "improper use" tone
[0089] The priority level specified in the Table refers to the
priority of a message from the perspective of the ICU. In
particular, the ICU is programmed to arbitrate among messages of
different priority according to these levels. This priority level
scheme is separate from the priority of messages in the J1587
protocol. The J1587 protocol implements a priority scheme for
controlling which messages take precedence when transmitted
concurrently on the data link.
[0090] While the above table provides specific implementation
details, it is possible to deviate from these specifications
without departing from the scope of the invention. A number of
additional design details are worth noting, keeping in mind that
these details are not necessary for implementation of the
invention. First, the auditory signal should be at least ten dB
above in-cab sound level in the particular frequency range. In
general, auditory warnings should be prioritized based on the
number of tones and the pauses between the tones. In particular,
the greater the number of tones (e.g., 1, 2, 4, 7) and the shorter
the pauses between the tones (e.g., 14 msec., 70 msec., 140 msec.),
the higher the priority. Preferably, the auditory tones for
collision warnings should be distinguishable from the auditory
tones used for other messages in the message center. In the current
implementation, the non-collision warnings have a noticeably lower
frequency (e.g., 560-840 Hz) than the collision detection warnings
(e.g., 1200-1800 Hz). In addition, to allow the driver to better
distinguish between different types of warnings, the message center
warnings use a repeating tone sequence of low to high, while the
collision warning tones use a tone sequence from high to low.
[0091] In the current implementation, the CWS ECU communicates
visual messages to the ICU via the J1708 data bus according to the
J1587 communication protocol. The CWS ECU is wired to the speaker
of the ICU and drives the speaker directly to generate auditory
warnings. In alternative implementations, the CWS ECU could
communicate messages for both auditory and visual warnings over the
data link using the J1587 standard, via discrete wiring, or some
combination of both.
[0092] To communicate instructions for visual warnings, the CWS ECU
broadcasts data bus messages over the J1708 data link. FIG. 10
illustrates a table listing the display message and the
corresponding data bus message used to instruct the ICU to display
it. The messages are listed in order of priority. If the ICU
receives a message with higher priority than the one it is
currently displaying, it displays the higher priority message as
soon as it receives the message from the data bus. As noted above,
the priority scheme implemented in the ICU is different than the
priority of message transmission on the J1587 data link. The
internal priority controlled within the ICU is reflected by the
ordering of the messages in the left-most column. The J1587 message
priority is noted in the right-most column.
[0093] Message 22 in the table shown in FIG. 10 is the data
required to display the following text message on the message
center:
[0094] Cruise Set to: xxMPH
[0095] Headway Set to: eee_s
[0096] where eee is the headway data in ASCII characters, example:
3.0, to be used in data bus message 219 226 8 48 8 2 16 140 e e e
chksum.
[0097] Following is a description of data bus message 22 (it
applies to other messages as well):
[0098] 219 226 8 48 8 2 16 140 e e e chksum.
[0099]
[0100] 219=MID (CWS ECU)
[0101] 226=PID (Text Message to Display)
[0102] 8=Number of bytes following
[0103] 48=Status Character 1 (48 decimal=0010000 binary)
[0104] Bit 8=0 (Use selected language)
[0105] Bit 7=0 (Message OK)
[0106] Bit 6=0 (Predefined text)
[0107] Bit 5=1 (Display buffered message)
[0108] Bit 4=0 (No sound; sound is controlled by the EVT-300
directly)
[0109] Bit 3=0 (No acknowledgement)
[0110] Bit 2=0 (Do not expect acknowledgement from operator)
[0111] Bit 1=0 (Do not send acknowledgement)
[0112] 8=Status Character 2 (8 decimal=00001000 binary)
[0113] Bits 8-4=00001 (defined as 1 Second; actually is less than 1
second)
[0114] Bits 3-1=000 (Priority 0)
[0115] 2=Message row/line number (second line of display)
[0116] 16=Message column number (16.sup.th column)
[0117] 140=Proprietary message (defined as the MID of the device
that has the display; MID 140=ICU)
[0118] e e e=Proprietary message (defined as the ASCII value for
the headway, ex. 3.0)
[0119] For more information on the message format, see Appendix C
of the J158 7 standard.
[0120] In managing the output of collision warning messages, the
ICU follows a set of predetermined guidelines. For each message in
the table of FIG. 10, the message center displays the corresponding
message for a predetermined period of time, namely 1.0 second. To
display the message a longer period of time, the CWS ECU sends the
same message again after 0.5 seconds, and continues re-sending at
this rate. Upon receiving a data bus message, the ICU sets a timer
to 1.0 second, and continues to display the message as long as the
timer has not elapsed. The ICU resets the timer (to a full 0.75
seconds) upon receiving a new message. This approach for re-sending
messages and re-setting the timer with each new message ensures
that the delay between transmissions of messages will not produce a
flicker in the ICU display.
[0121] Another feature relating to the integration of collision
warnings into the message center is the ability to select a driver
for the purpose of logging events on a per driver basis. The ICU
provides a display that enables the driver to enter a driver
identification (ID), and is programmed to broadcast a message on
the data bus including the driver ID. The CWS ECU and other ECUs
are programmed to store the driver ID and record it along with
events that they monitor. In particular, the current implementation
of the ICU broadcasts the driver ID in PID 507 of the J1587
protocol, in response to a request from another ECU (e.g., the CWS
ECU) using MID 219.
[0122] In the current implementation, the ICU prompts the driver to
enter the driver ID during the ignition sequence. During the
ignition sequence, the message center displays screens that prompt
the driver to accept the currently active driver ID or to select a
new one. FIG. 11 illustrates an example of the message center
displays 1100, 1102 used to prompt the driver for the ID. The
driver can either select the active driver ID by pressing the set
key in response to the first screen, or select a new driver by
pressing an arrow key as shown. After the driver presses the
acknowledgement key at either screen 1100, 1102, the message center
continues with the ignition sequence as shown in the third screen
1104 in FIG. 11.
[0123] In response to the selection of the driver ID, the ICU sends
a PID 507 message, Driver Identification, over the SAE J1708/1587
data link to indicate what driver is active (Driver 1 or Driver 2)
as soon as the driver acknowledges the ICU screen prompt, per the
following message formats:
9 Driver 1 MID PID n ASCII ASCII 140 507 2 49 42 Cksum (1) (*)
[0124]
[0125] Note that PID 507 is sent as two consecutive bytes: 255
followed by 251.
[0126]
10 Driver 2 MID PID n ASCII ASCII 140 507 2 50 42 Cksum (2) (*)
[0127] Again, note that PID 507 is sent as two consecutive bytes:
255 followed by 251. The message will be available from the ICU
also upon request, per the following message format:
11 Request MID PID a b 219 384 251 140 Cksum
[0128]
[0129] Note that PID 384 is sent as two consecutive bytes: 255
followed by 128.
[0130] Integration of Adaptive Cruise Control into the Message
Center
[0131] The driver interface for adaptive cruise control is
integrated into the ICU and its message center. In the current
implementation, the driver interface for the ACC system includes
the ICU's message center and indicator lights as well as input
switches on the dash. The ICU integrates ACC related information
and warnings into the message center and also controls ACC related
indicator lights. When the driver enters ACC input via dash
switches, the ICU displays visual feedback to the driver via
alphanumeric messages on the display screen.
[0132] The ACC system includes the CWS ECU, the ICU, the engine
ECU, the transmission ECU, the anti-lock brake ECU, and the engine
retarder ECU. The ACC software executing on the CWS ECU uses the
collision warning sensors to track targets and send messages to
other ECUs to reduce vehicle speed when a target is too close to
the truck. For example, in the current implementation based on the
EVT-300 collision warning system from Eaton VORAD technologies, the
CWS ECU maintains a constant headway with a lead vehicle by sending
messages to: 1) control the throttle; 2) invoke the engine brake;
and 3) downshift the transmission. Depending on the circumstances,
the CWS ECU sends messages to the engine ECU to defuel the engine
via the speed/torque limit override mode of the J1939 standard. It
may also send messages to the engine brake to retard the engine via
the torque control override mode of the J1939 standard. Finally, it
may send a message to the transmission ECU to downshift the
transmission according to the J1939 standard.
[0133] The CWS ECU communicates ACC related information to the ICU
via either discrete wiring, a data link, or some combination of
discrete wiring and a data link. In the implementation based on the
EVT-300 collision warning system, the CWS ECU communicates
instructions for visual messages to the ICU via the J1708 data
link, and sends control signals for auditory warnings directly to
the ICU speakers via discrete wiring. In an alternative
implementation based on the ADC adaptive cruise control system, the
CWS ECU communicates control messages for auditory and visual
messages to the ICU via the J1939 data link.
[0134] The driver provides ACC related input via dash controls in
the cabin. These controls include cruise control switches such as
an ON/OFF/mode switch, and a SET/RESUME switch. The ON/OFF/mode
switch enables the driver to turn on and off cruise control and, in
some implementations, switch between ACC and conventional cruise
control (i.e. cruise control without headway control). The
operation of this control switch varies, depending on the
implementation. For example, in one implementation, ACC is always
active when the driver turns on the cruise control. The only
exception is failure of ACC, in which case, the system reverts to
conventional cruise control operation. In an alternative
implementation, the driver can switch between no cruise control
(OFF), adaptive cruise control (Adaptive Cruise), and conventional
cruise control (Cruise). In this case, the ON/OFF/mode switch is a
three-position switch with positions for Adaptive Cruise, Cruise
and OFF.
[0135] The SET/RESUME switch is similar to conventional cruise
control in that it allows the driver to enter the set speed and
resume cruise control operation. When the driver actuates this
switch, the cruise control within the engine ECU communicates the
set speed to the CWS ECU and the ICU via the J1708 data link.
[0136] Another ACC related switch is a volume control, which is
similar to the volume control used in the collision warning system
to adjust the volume for auditory warnings. In implementations
where this switch is wired to the CWS ECU, the CWS receives the
input and formulates a message to the ICU, instructing it to
display a message showing the volume level. Similar functionality
may be achieved in an implementation where the volume switch is
wired to the ICU directly. In this case, the ICU displays the
volume level in response to direct inputs from the volume
control.
[0137] Finally, there is a headway control switch, which enables
the driver to set the headway. In implementations where the headway
control is wired to the CWS ECU, the CWS receives the input and
formulates a message to the ICU for the J1708 data link,
instructing it to display a message showing the selected headway.
Similar functionality may be achieved in an implementation where
the headway control is wired to the ICU directly. In this case, the
ICU displays the selected headway in response to direct inputs from
the headway control and formulates a message to the CWS ECU for the
J1708, informing it of the headway setting.
[0138] The method for communicating driver input to the ACC system
varies, depending on the implementation. In the implementation that
integrates the EVT-300 collision warning system, the switches are
wired into the CWS ECU, and the CWS communicates instructions for
visual messages to the ICU. In the implementation that integrates
the ADC distance control system, the switches are wired directly
into the ICU, the ICU communicates headway parameters to the
distance control system.
[0139] The ICU provides three microprocessor controlled indicator
lights for ACC functions located near the message center. One light
indicates whether the adaptive cruise control is active. The ICU
detects this condition from the data link via messages from the
engine ECU and CWS ECU. The condition for this active light is: no
active fault from the CWS ECU (MID 219), battery voltage (PID 168)
is normal in the CWS ECU, and the cruise control is active (PID 85)
from the engine ECU (MID 128).
[0140] A second light indicates that the ACC system has detected a
target. The ICU activates this light for preprogrammed duration
(e.g., 200 ms) on receipt of a predetermined message (e.g.,
219.sub.--226.sub.--6.sub.--48_-
8.sub.--1.sub.--1.sub.--140_4_CHKSUM) from the CWS ECU on the data
bus.
[0141] Finally, the third light indicates that the ACC system has
failed from the CWS ECU. The ICU detects this condition by
detecting an active fault or no battery voltage PID 168 signal from
the CWS ECU (MID 219). In this implementation, the battery voltage
signal from the CWS ECU acts as a "heartbeat" indicating that the
CWS ECU is operating.
[0142] In addition to the ACC-related indicator lights, the ICU
also displays visual messages on its display screen. In the current
implementation, the ACC related display screens fall into three
categories: function set messages, failure warnings, and danger
ahead warnings. FIG. 12 illustrates examples of the ACC related
indicator lights and these display screens.
[0143] The ICU displays function set messages in response to input
from the driver setting parameters relating to adaptive cruise
control. When the driver enters the set speed using the SET/RESUME
switch, the ICU displays a screen 1200 with a text message
indicating that radar cruise is active, the value of the set speed,
and the time headway as shown in FIG. 12. Also, when the driver
sets the headway via the headway switch on the dash, the message
center displays a screen 1202 showing the time headway setting. The
terms "min" and "max" are the lower and upper limits of a bar graph
display, graphically depicting time headway. As the driver
increments or decrements the current value of the headway, the
message center displays the current value of the headway.
[0144] The ACC system uses the ICU's indicator lights to show
changes in its status. When the driver activates the adaptive
cruise control system, the ICU illuminates the radar cruise
indicator light 1204. While in adaptive cruise control mode, the
ICU illuminates a DETECT indicator light 1206 when the collision
warning system is tracking a vehicle.
[0145] The message center displays a warning screen 1208 in FIG. 12
when the radar system fails. In addition, the ICU illuminates a
radar fail indicator light 1210.
[0146] While the adaptive cruise control system is active, the
message center also displays "danger ahead" messages 1212, 1214 in
response to collision detection events from the collision warning
system These messages are triggered as described above in
connection with the integration of the ECU collision warning system
into the ICU message center. The message center displays the set
speed along with the "danger ahead" message as shown in screen
1212. However, as the urgency of the "danger ahead" message
increases, the ICU removes the set speed and displays a larger
triangle to emphasize the increase in danger as shown in screen
1214.
[0147] In the event that the adaptive cruise control system becomes
inactive while the vehicle is in cruise control mode, the message
center displays a warning such as the one shown in display screen
1216 in FIG. 12 to indicate to the driver that the radar cruise
control is off. At the same time, the ICU turns off an indicator
light 1218 to indicate that the vehicle is not in cruise control
mode. While the vehicle is in cruise control mode, the collision
warning system and the ICU revert back to the message scheme
described above in connection with collision detection warnings. In
particular, the message center displays progressively more intense
warning messages such as the ones shown in screens 1220 and 1222 in
FIG. 12 when the collision warning system detects that the
following distance has fallen below predetermined thresholds such
as headway values of one and two seconds. The difference between
the collision warnings shown in screens 1220 and 1222, and the
collision warnings during ACC mode is that the ICU displays the set
speed (e.g., screen 1212) during ACC mode, as long as the severity
of the message has not increased to the point where the warning
triangle dominates the display screen (e.g., screen 1214).
[0148] The ICU determines when to display failure related messages
by monitoring the status of the adaptive cruise control system via
the J1708 data link. The collision warning system conducts periodic
self checks (e.g., every fifteen seconds) to determine if it is
operating properly. It then sends a message on the J1939 data link
indicating that the adaptive cruise control system is active every
100 msec, as long as it has not detected any critical faults that
might prevent proper operation. In the event that the CWS ECU
determines that it has a critical fault, then it discontinues
sending the message onto the J1939 data link, and sends a fault
message via the J1587 data link to the ICU for the driver display
In response to the lack of heartbeat from the CWS ECU, the engine
ECU reverts back to normal throttle control rather than cruise
control mode. In response to the fault message on the data link,
the ICU displays message screen 1208 shown in FIG. 12 indicating a
radar cruise control failure
[0149] The engine ECU is programmed to monitor the status of the
ACC system when the ACC system is installed on the vehicle The
engine ECU monitors the status of the adaptive cruise control
system via the J1939 databus. The collision warning system is
powered on when the ignition is switched on. After a self-check,
the ACC system starts transmitting the heartbeat. The engine ECU is
programmed to check whether the heartbeat is present on the databus
at ignition startup. If the heartbeat is not present at that time,
the engine ECU disables its ACC mode and returns to throttle mode.
After power-up, the engine ECU continually monitors for the
heartbeat and is programmed to assume that the ACC is no longer
functioning if it does not receive a heartbeat for over a
pre-determined period of time (e.g., 350 msec). In this case, it
disables the cruise control and returns to throttle control.
[0150] To enable conventional cruise control when ACC fails, the
driver can toggle the cruise control ON/OFF switch twice within ten
seconds. Once this sequence is accomplished, the engine ECU enables
conventional cruise control. If the ACC heartbeat comes back to the
databus, then the engine ECU will allow ACC operation, but only at
the next cruise control power ON cycle. This avoids the possibility
of the engine being in conventional cruise control mode and
adaptive cruise control being reactivated without driver
notification and acknowledgement.
[0151] The adaptive cruise control messages are integrated into the
ICU's message center in a similar manner as the collision warning
messages. Table 5 above illustrates the priority of collision
warning messages in the context of the ICU's prioritization scheme,
which includes danger, warning, and caution alerts. When the CWS
ECU detects collision warning events during operation of the ACC
system, it sends messages to the ICU communicating these events.
The ICU treats these messages as having the same priority as in the
case where the ACC is not active. When the ICU detects a condition
from the data link indicating that the ACC system has failed or has
become inactive, it generates a "warning" level message (see, e.g.,
priority level 5 in Table 5, showing the priority of a "warning"
level message relative to collision alerts and other ICU messages).
Finally, in response to user input relating to the ACC system, the
ICU displays function set messages, such as the time headway
setting (see, e.g., messages 6-13 in FIG. 10), and the alert volume
(see, e.g., messages 14-21 in FIG. 10). When the driver
changes/enters the set speed or headway, the ICU displays the set
speed and headway information as illustrated in screen 1200, FIG.
12. The ICU also displays screen 1200 while in ACC mode in response
to detecting that the vehicle speed from the engine ECU has dropped
an increment of 5 MPH below the set speed. FIG. 10 shows this
message as message number 22. Note that the ICU prioritizes this
message below that of the function set messages (e.g., messages
6-21 in FIG. 10) and the collision warning messages (e.g., messages
1-5 in FIG. 10).
[0152] Integration of Transmission Display into the Message
Center
[0153] The ICU integrates the transmission display into the message
center. One particularly advantageous feature of the ICU is the
ability to provide a standard interface for a variety of
transmission types, such as automated mechanical transmissions,
automatic transmissions, and mechanical (i.e., manual)
transmissions. The message center displays the current gear of the
vehicle and, for some transmission systems, the driving mode of the
transmission (e.g., automatic or manual mode for an automated
mechanical transmission). The message center may also display
indicators (e.g., up/down arrows) to prompt the driver to shift for
better fuel economy.
[0154] In addition to visual information, the ICU provides auditory
information as well. The ICU generates an auditory warning to
indicate to the driver that an inappropriate gear has been
selected.
[0155] In the case of both visual and auditory information, the
transmission ECU communicates instructions for this information to
the ICU via the J1708 link according to the J1587 standard.
[0156] FIG. 13 illustrates examples of display screens 1300, 1302
that display transmission information in the current
implementation. In providing this display information, the ICU
works in conjunction with the transmission ICU. The transmission
ECU receives instructions for shifting the transmission and
selecting the driving mode from a shift lever in the vehicle. For
more information on the operation of the shift lever, see
co-pending application entitled, "Lever Assembly for an
Electronically Controllable Vehicle Transmission", which is
incorporated by reference above.
[0157] As illustrated in display screen 1300 shown in FIG. 13, the
message center displays at least three characters (e.g., 1304,
1306, 1308) that are related to the transmission display. At least
one character 1306 displays the current gear. Another character
1308 displays the driving mode of the transmission. Another
character 1304 may be used to separate the transmission display
from other messages. Since the message center always provides a
transmission display, it indicates the characters relating to the
transmission display along with whatever else is currently
displayed, which is either the driver's selectable default screen
or an alert screen.
[0158] The second display screen 1302 shown in FIG. 13, illustrates
the case where at least one character 1310 display an up or down
arrow to prompt the driver to shift to improve fuel economy. In
this case, the arrow character also functions to separate the
transmission information from other information that is currently
presented on the same line of the display.
[0159] As noted above, the ICU can provide visual and auditory
information for a variety of transmission systems. In one
implementation, the message center is used to display transmission
information for an automated mechanical transmission. The driver
controls the transmission via a shift lever that enables the driver
to select a gear by actuating the lever, and also allows the driver
to select the driving mode via a switch on the stalk of the lever.
In this particular implementation, the message center displays the
current gear at all times in which the automatic shifting mode is
selected. The message center displays the current gear in manual
shifting mode until the driver selects a new gear through actuation
of the shift lever. The new gear may be flashed for a predetermined
time period (e.g., 500 msec intervals) until the shift is
completed. For normal up or down shifting, the transmission display
will not appear to shift to the driver because one cycle of the
flash interval corresponds roughly to the average time that the
automated mechanical transmission system takes to complete a shift.
When a driver makes a shift request for activation of the shift
lever, the message center only displays the selected gear if it is
currently available. The message center informs the driver that the
selected gear has been engaged by ceasing the flashing of the
selected gear.
[0160] When a driver selects a gear or mode that is unavailable via
the shift lever, the ICU generates an auditory tone indicating that
it is unavailable. In the current implementation, for example, the
ICU generates a pure square wave tone at 250 Hz for 300 msec. This
particular tone was selected because it is not easily masked in the
cabin environment and is used with other systems to represent an
action that is inappropriate, not allowed, or requires different
input The same tone is used to signal an unavailable mode selection
(e.g., moving the mode switch to reverse at highway speed). Instead
of a single tone, the ICU repeats this tone at periodic intervals
until the selector has been put back into the appropriate position.
In addition, the message center generates a level 2 warning message
with the corresponding auditory tone and display protocol.
[0161] Conclusion
[0162] While the invention is described with reference to a
specific implementation, it is important to emphasize that the
invention is not limited to the specific design details of this
implementation. The message display integrates message displays
from a variety of different types and models of ECUs and other
sensors onboard the vehicle. The format of the data does not have
to be in the form of serial data from a serial data link as in a
system built for a J1708 data link. Instead, the data can be
obtained from another type of data bus or through discrete
wiring.
[0163] The software implementation can vary as well. The precise
logic used to prioritize messages can vary.
[0164] Having described and illustrated the principles of our
invention with reference to a specific implementation and possible
alternatives, it should be apparent that the invention can be
modified in arrangement and detail without departing from its
principles. Accordingly, we claim all modifications as may come
within the scope and spirit of the following claims.
* * * * *