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FIELD OF INVENTION
This invention relates to a system to detect instance of -
intermittent electrical power supply loss/reset/disability in
particular ECU (s) of vehicle available in the network of ECUs.
BACKGROUND/PRIOR ART
Various network systems for use in an automobile, such as CAN
(control area network), have been developed. Plural ECUs are
interconnected in such a network, and it is required to detect
communication failures in the network. Various systems for
detecting the communication failures are proposed.
The existing systems do not keep track of the number of reset
events that have occurred with ECUs having common trigger
signals, as a plausibility check between the ECUs. This leads to the
misconception that the reset never occurred and as a result, the
re-occurrence of the reset under critical conditions could lead to
fatal incidents.
For example:- A power glitch for the ABS controller at the instant
of breaking while travelling at high speeds.
The master ECU (ECU reporting error) connected to various sub-
ECUs of vehicle can keep track of event only after a preset time
period not at every instance.
Currently there are systems (ECU) which detect a reset internally
but the counts are not compared with other external ECU in the
network.
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In view of the above, it is required to develop a system which is
able to detect instance of intermittent electrical power supply
loss/reset/disability in any of the ECUs in the network, in which
each of the ECUs is meant for a particular purpose.
Hence, the invention introduces a system to detect instance of
intermittent electrical power supply loss/reset/disability in
particular ECU (s) of vehicle.
OBJECTS OF THE INVENTION
Primary object of the present invention is to provide a system to
detect instance of intermittent electrical power supply
loss/reset/disability in particular ECU (s) of vehicle.
Another object of the present invention is to provide a system to
detect instance of intermittent electrical power supply
loss/ reset/ disability in particular ECU (s) of vehicle which can
detect the fault even with master ECU (ECU reporting error).
Yet another object of the present invention is to provide a system
to detect instance of intermittent electrical power supply
loss/reset/disability in particular ECU (s) of vehicle in which all
the ECUs of network can keep track of each other through
common networking.
SUMMARY OF THE INVENTION
According to this invention, there is provided a system to detect
instance of intermittent electrical power supply
loss/reset/disability in particular ECU (s) of vehicle comprising a
plurality of ECUs of vehicle in communication with a master ECU
(ECU reporting error) through a communication line wherein each
of the ECUs in the communication network is installed with a
software to detect every instance of intermittent electrical power
supply loss in any of the ECUs.
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BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Further objects and advantages of this invention will be more
apparent from the ensuing description when read in conjunction
with the accompanying drawings and wherein:
FIG. 1 shows: Examplary embodiment of vehicle ECU
architecture with trigger points and circuit
break points;
• FIG. 2 shows: flow chart illustrating a process for
comparing the count for each event of
ECUs triggered by common trigger event;
DETAIL DESCRIPTION OF THE INVENTION WITH REFERENCE
TO THE ACCOMPANYING DRAWINGS
Communication network in an automotive vehicle includes ECUs
in communication with each other so as to share information and
data with each other i.e. to send and receive information and data
through common communication line.
The main ECU (ECU reporting error) includes a communication
• module communicating with other communication modules
included in the sub-ECUs by means of control area network (CAN)
without restricting scope of the invention to the same.
Each ECU also comprises a respective micro computer for
performing a respective function as each ECU is meant for a
particular purpose for example ABS-ECU that controls braking
force on the rear wheels and transmission ECU for controlling an
automatic transmission.
Undesirable power loss/reset/disability or a reset may happen in
any ECU in the vehicle which may go unnoticed. This is due to
limitation in the diagnostics. Each ECU may be capable of
determining a power loss/reset. However, in each ECU it is not
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known whether the power loss/reset/disability was desirable or
undesirable. This problem can be solved if power
loss/ reset/ disability information is shared between ECU's. Using
this information, each ECU can determine if the power
loss/reset/disability was desirable or undesirable. This is
explained herein below: -
There are two ways in which a controller experiences reset:-
1. Loss of power supply in ECU:- For example battery supply to
the controller is disrupted.
2. Loss of signals in ECU:- For example signals such as
ignition on.
In this regard reference may be made to fig.l, in which the ECUs
(1, 2, 3, 4) are triggered by means of battery power supply (B)/
Ignition ON (A).
For a particular external trigger event (such as accessories ON, IGON/
key insert, Cranking, Car Unlock, remote) the ECU is reset,
sometimes the trigger events are intentional and at some times it is
unintentional (e.g momentary circuit break).
Detection of power loss in ECU according to the present invention
can be described with reference to fig. 2.
All resets which are caused by a particular event are grouped and
a count is maintained in each ECU and stored in its memory which
does not loose data in power loss condition and at the moment of
restart. This count can be compared with all other ECU's having
common trigger events by communication through CAN. In case
there is a mismatch in the counts of a common event, it can be
concluded that a particular ECU has been reset more or less times
than the number of intended trigger events.
For instance if the ABS ECU, Airbag ECU and the EMS ECU are all
powered on by switching on the ignition switch, the power on reset
count for each of these ECUs should be same (eg: x). For the next
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driving cycle the count in each ECU should be incremented by one
i.e. (x+1), in case of the event where any ECU reports a count (x+2)
it can be concluded that an intentional power on reset has
occurred in that particular ECU. By this plausibility check between
ECU's an undesirable reset can be detected and required action
can be taken. Along with this some important vehicle parameters
(vehicle speed, Engine speed) can be captured during restart and
can be communicated to verify the particular instances at which
each of the ECUs was reset.
Thus, the invention is able to detect every instance of intermittent
electrical power supply loss/reset/disability in any of the ECUs,
which is maintained in the record of respective ECU so as to keep
track of the event. So that accordingly the problem can be fixed to
avoid the same in future.
Thus, all ECUs including master ECU (ECU reporting error) record
event occurring at each instance. By comparing count of
occurrence of an event in the corresponding ECUs triggered by
common trigger event the problem can be located as already
described, for which each ECU is installed with a software.
Detection can be done by vehicle user with the help of scanner.
. Advantageous Features
- More accurate and precise in detection of problem.
- Addressing issue in earlier stage thereby avoiding casualty.
- Addressing of safety measures effectively.
It is to be noted that the present invention is susceptible to
modifications, adaptations and changes by those skilled in the art.
Such variant embodiments employing the concepts and features of
this invention are intended to be within the scope of the present
invention, which is further set forth under the following claims:-

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WE CLAIM:
1. A system to detect instance of intermittent electrical power
supply loss/reset/disability in particular ECU (s) of vehicle
comprising a plurality of ECUs of vehicle in communication
with a master ECU through a communication line wherein
each of the ECUs in the communication network is installed
with a software to detect every instance of intermittent
electrical power supply loss in any of the ECUs.
2. A system to detect instance of intermittent electrical power
supply loss/reset/disability in particular ECU (s) of vehicle
as claimed in claim 1, wherein the ECUs operated by
common trigger event such as key insert/ battery
on/remote/accessories on are grouped.
3. A system to detect instance of intermittent electrical power
supply loss/reset/disability in particular ECU (s) of vehicle
as claimed in claim 1 or 2, wherein said ECUs in a group are
maintained with an individual count of resets for a particular
event.
4. A system to detect instance of intermittent electrical power
supply loss/reset/disability in particular ECU (s) of vehicle
as claimed in any of the preceding claims, wherein the count
of corresponding ECUs having common trigger event is
compared to detect fault with particular ECU involving
mismatch in the counting of a common event.
5. A system to detect instance of intermittent electrical power
supply loss/reset/disability in particular ECU (s) of vehicle
as claimed in any of the preceding claims, wherein the
trigger point can be detectable with a fault.
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6. A system to detect instance of intermittent electrical power
supply loss/reset/disability in particular ECU (s) of vehicle
as claimed in any of the preceding claims, wherein the ECUs,
all of which can monitor each other including the master
ECU(ECU reporting the error) for detection of any fault.
7. A system to detect instance of intermittent electrical power
supply loss/reset/disability in particular ECU (s) of vehicle
as claimed in any of the preceding claims, wherein the type
of fault in the ECUs can be specified.
8. A system to detect instance of intermittent electrical power
supply loss/reset/disability in particular ECU (s) of vehicle
as claimed in any of the preceding claims is associated with
the advantageous features such as herein described.
9. A system to detect instance of intermittent electrical power
supply loss/reset/disability in particular ECU (s) of vehicle
substantially as herein described with reference to the
accompanying drawings.
Dated this 27thday of August, 2014
(SOMATJANI MISHRA)
OF L.S.DAVAR 8B CO.,
APPLICANT'S AGENT