FORM 2
THE PATENTS ACT 1970 (as amended) [39 OF 1970]
AND
The Patents Rules, 2003
COMPLETE SPECIFICATION
[See Section 10 and Rule 13]
TITLE OF THE INVENTION AN OCCUPANT SAFETY SYSTEM FOR A VEHICLE
NAME OF THE APPLICANT
TATA MOTORS LIMITED
an Indian company having its registered office at
Bombay house, 24 Homi Mody Street,
Hutatma Chowk, Mumbai 400 001,
Maharashtra, India.
INVENTORS
Divyata Khachane and Nikhil Zopate
Both are Indian National
of Tata Motors Limited
Bombay house, 24 Homi Mody Street,
Hutatma Chowk, Mumbai 400 001,
Maharashtra, India.
PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed.

FIELD OF THE INVENTION
The present invention relates to an occupant safety system for a vehicle, and more particularly, the present invention relates to the occupant safety system for the vehicle, especially to prevent speeding of the vehicle beyond a threshold speed in the absence of safety parameters like seat belt, door ajar etc.
BACKGROUND OF THE INVENTION
It has been observed with the increase of vehicle the accident has also increased. Government has mandated certain norms for the safety of the occupant in the vehicle, which includes fastening of seat belt etc. however it has been observed that not many strictly follows such norms and resulting in fatal accidents. There are other reasons as well including door ajar i.e. sometimes door remains open and the driver remains unaware about it. As a result with speeding of the vehicle, it may result in an accident. In order to avoid the same, vehicle has sound indicator and also tell-tale to inform that the seat belt is not fasten or for door ajar. These scenarios may lead to negligence of seat belt wearing and door ajar, which may cause major injury to occupants’ in accidental situations.
Therefore, the problem to be solved is to provide an efficient system that ensure safety of the occupants against accidents that occur due to negligence of the driver towards safety parameters like seat belt, door ajar etc. and the problem is solved in the present invention by an occupant safety system, which includes occupant detecting unit and sensing unit that senses current status or present value of different parameters and transmit the signal to a control unit, which compares it with predefined value such that in case the present value and the predefined value differs from each other of the parameters, the electronic control unit controls the speed of the vehicle to a threshold speed to ensure safety of the occupant in the vehicle.

OBJECTS OF THE DISCLOSURE
One object of the present disclosure is to provide an occupant safety system for a vehicle wherein the ECU control the speed of the vehicle to a threshold speed when present value of one of the parameters differs from the actual value or status.
Another object of the present disclosure is to provide an occupant safety system for a vehicle, the ECU control the speed of the vehicle to a threshold speed when the driver is not wearing seat belt or for door ajar etc.
SUMMARY OF THE INVENTION
An embodiment of the present invention discloses an occupant safety system for a vehicle comprising: an occupant detecting unit adapted to detect the presence of an occupant in said vehicle; a sensing unit configured to sense a present value of a predefined parameter; a control unit electrically coupled to said sensing unit to receive a signal from said sensing unit based on the present value of the predefined parameter, said control unit compares said present value with a predefined value of said predefined parameter; and an electronic control unit (ECU) coupled with said control unit and adapted to control speed of said vehicle, wherein said ECU controls speed of said vehicle to a threshold speed when said present value of said predefined parameter is different than said predefined value of said predefined parameter to ensure safety of said occupant in said vehicle.
In an embodiment of the present invention the sensing unit senses said predefined parameter from at least one of a seat belt, a parking brake, a door ajar and a seat belt buckle switch.

In an embodiment of the present invention the sensing unit includes a seat belt sensor to sense said predefined value including said seat belt wearing by said occupant, a parking brake sensor to sense disengagement of parking brake, a door ajar sensor to sense complete door closure, and a seat belt buckle switch sensor to sense dis-engagement of a buckle clip from a holder.
In an embodiment of the present invention the sensing unit includes a speed sensor to sense speed of said vehicle.
In an embodiment of the present invention the control unit receives signal from a seat belt length measurement transducer configured to measure length of a seat belt pulled out for its engagement.
In an embodiment of the present invention the control unit compares length of said seat belt pulled as measured by said seat belt length measurement transducer with a predefined length to confirm engagement of said seat belt.
In an embodiment of the present invention the occupant detection system detects number of occupants and their position in said vehicle and transmitted signal to said control unit.
In an embodiment of the present invention the control unit compares speed of said vehicle sensed by said speed sensor and compares with said threshold speed, and instructs said ECU to lower speed when said sensed present value of said predefined parameter sensed by said sensing unit differs from said predefined value of said predefined parameter.
In an embodiment of the present invention the ECU allows increasing speed of said vehicle above said threshold speed when sensed present value of said

predefined parameter sensed by said sensing unit becomes equal from said predefined value of said predefined parameter.
In an embodiment of the present invention the control unit includes a bypass feature to bypass speed control to said threshold speed.
BRIEF DESCRIPTION OF DRAWINGS
The disclosure itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying figures. One or more embodiments are now described, by way of example only, with reference to the accompanying figures wherein like reference numerals represent like elements and in which:
FIG. 1 illustrates an embodiment of the present invention depicting block diagram of the working of the system;
FIG. 2 illustrates an embodiment of the present invention depicting flow chart reflecting working of the system.
The figures depict embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the system illustrated herein may be employed without departing from the principles of the disclosure described herein.

Referral Numeral:
Reference Numeral Description
10 Occupant detecting unit
20 Seat belt sensor
30 Parking brake sensor
40 Door ajar sensor
50 Vehicle speed sensor
60 Seat belt buckle switch sensor
70 Seat belt length measurement transducer
80 Control unit
90 Electronic control unit (ECU)
DETAILED DESCRIPTION OF THE INVENTION
The foregoing has broadly outlined the features and technical advantages of the present disclosure in order that the detailed description of the disclosure that follows may be better understood. Additional features and advantages of the disclosure will be described hereinafter which form the subject of the claims of the disclosure. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the disclosure as set forth in the appended claims. The novel features which are believed to be characteristic of the disclosure, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of

the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present disclosure.
An embodiment of the present invention discloses an occupant safety system for a vehicle to ensure safety of the occupants. The system includes an occupant detecting unit (10) which is adapted to detect the presence of the occupant in the vehicle. The system also includes a sensing unit which senses the present value of the predefined parameter and transmit the same to the control unit (80). The control unit (80) also includes a predefined value of the predefined parameter with which the actual or present value is compared. The predefined parameters can includes different safety parameters like seat belt, door ajar etc.
As shown in Fig. 1, the control unit (80) receives signal from sensing units which senses different predefined parameters as given below:
Occupant detecting unit (10):
The occupant detecting unit includes a sensor that detects the presence of a person in the vehicle. The signal from the occupant detecting unit (10) is provided to control unit through which number of occupants setting inside the vehicle with their location is determined.
Seat Belt Sensor (20):
Seat Belt sensor (20) determines whether the occupants’ are wearing seat belt or not. The control unit based on the inputs from this sensing unit take decision. The predefined value for this predefined parameter of sear belt is that the seat belt should be fasten and in case the seat belt is not fasten the present value differs from the predefined value.
Parking Brake Sensor (30):
Parking brake sensor (30) detects whether the parking brake is engaged or not.
Control unit will take reference of this signal for performing bypass procedure.

The predefined value for this predefined parameter of parking brake sensor would be that the parking break should be released and in case the parking brake is not released, the present value will differ from the predefined value.
Door Ajar Sensor (40):
Door ajar or door open sensor (40) senses the complete door closure. This signal given as an input to control unit. The predefined value of the predefined parameter i.e. door ajar would be that the door should be closed and in case the present value depicts that there is a door ajar, then the present value and the predefined value will differ. Depending on the door ajar signal control unit will take decision whether to limit the speed or not.
Vehicle speed Sensor (50):
Vehicle speed sensor (50) senses the speed of the vehicle which will be provided to control unit to check the speed limit condition and other condition related to vehicle speed.
Seat Belt Buckle Switch Sensor (60):
Seat belt buckle switch sensor (60) senses the disengagement and engagement of buckle clip from its holder. The control unit (80) then use this signal to analyze defined operation sequence and buckle holder mechanical failure.
Seat Belt Length Measurement Transducer (70):
Seat Belt Length Measurement Transducer (70) measures the length of belt pulled out for its engagement. This signal is given as an input to control unit (80) which will ensure the misuse of seatbelt or tampering of system. The control unit compares length of said seat belt pulled as measured by the seat belt length measurement transducer with a predefined length to confirm engagement of said seat belt. The seatbelt length should be greater than or equal to predefined value of the seat belt length value for detection of true engagement of seat belt otherwise false engagement of seat belt will be considered.

Based on the inputs received from the sensors, the control unit signals the electronic control unit (ECU) to control the speed of the vehicle to a threshold speed. The control unit (80) is electrically coupled to the sensing unit to receive a signal from the sensing unit based on the present value of the predefined parameters. The control unit (80) compares the present value with a predefined value of the predefined parameter.
As shown in Fig. 2, this system uses different kind of sensors like seat belt sensor (20), parking brake sensor (30), door ajar / door open sensor (40), vehicle speed sensor (50), seat belt buckle switch sensor (60), Occupant detection sensor (ODS), Seat belt length measurement transducer (70), the output of these sensors are directly connected to control unit (80) of the occupant safety system. These sensors are connected by using different communication protocol like Analog, Digital, CAN, LIN etc. The control unit (80) analyzes sensor outputs and take appropriate decision to enhance safety while driving the vehicle by gradually limiting the speed of vehicle while unsafe vehicle driving conditions.
Whenever vehicle speed will exceed speed value greater than predefined threshold, the control unit (80) will check whether the present value of the predefined parameter is same as predefined value, i.e. for proper closure of all vehicle doors and seat belt wore by all occupants etc. in the vehicle. If any door open / ajar (based on door ajar / door open sensor parameters) signal and /or any seat belt not wore by any occupant (based on occupant detection sensor, seat belt sensor and seat belt buckle switch sensor and seat belt length measurement transducer parameters) identified by control unit (80), speed limiting signal will be sent to EMS ECU (90) of vehicle. The ECU (90) is coupled with the control unit and adapted to control speed of the vehicle.
Whenever vehicle occupant travel without wearing seat belt or while door partially open / door ajar condition with vehicle speed greater than predefined

value or threshold speed, the control unit will intimate the driver for seat belt engagement / proper door closer with tell-tale and audio alert. Control unit will initiate the procedure for limiting vehicle speed gradually by providing warning to driver within predefined time. There will be special procedure defined in control unit for speed limiting in unintended conditions where speed will be restricted with respect to time through limiting curve.
If any occupant engaged the seat belt at any time during speed limiting procedure or after the speed limiting procedure then vehicle speed will increases gradually to normal speed in predefined time. Also same procedure will be applicable to door open / door ajar conditions and other parameters.
Control unit is enabled with seat belt length measurement transducer which will measure the length of seat belt pulled out for its engagement. The mapping of minimum seat belt length pulled out for its engagement will be defined in control unit (80) as predefined value. If the present value is less than minimum seat belt length value i.e. predefined value, then control unit will detect this condition as misuse of seat belt or tampering of system. The control unit (80) will proceed with lowering of the speed of the vehicle.
Control unit also has an inbuilt feature to bypass the system in case of emergency. Whenever occupant want to bypass system, occupants has to follow bypass procedure. To bypass the system, occupant needs make vehicle speed zero and open any two door of vehicle, then occupant needs to do engage and disengage cycle of the seat belt for predefined number of time in predefined time interval in the vehicle key ON condition. With this bypass feature, system can be disabled for particular seat or for complete vehicle.
Bypass feature will be active for current drive cycle only (drive cycle in which bypass feature activated) and will restore normal functionality of occupant safety system in next drive cycle.

At all instant of time, control unit will monitor and analyses all input data and operation sequence, whenever any failure is observed with respect to input sensor, transducer and input signals then control unit will decide whether speed limit to be initiated or not. For example – while driving the vehicle, engaged seat belt disengage automatically due to some mechanical failure in seat buckle. This type of failure condition will be analyzed by controller and speed limiting will not be initiated.

We Claim:
1. An occupant safety system for a vehicle comprising:
an occupant detecting unit (10) adapted to detect the presence of an
occupant in said vehicle;
a sensing unit configured to sense a present value of a predefined
parameter;
a control unit (80) electrically coupled to said sensing unit to receive a
signal from said sensing unit based on the present value of the predefined
parameter, said control unit compares said present value with a predefined
value of said predefined parameter; and
an electronic control unit (ECU) (90) coupled with said control unit (80)
and adapted to control speed of said vehicle,
wherein said ECU (90) controls speed of said vehicle to a threshold speed
when said present value of said predefined parameter is different than said
predefined value of said predefined parameter to ensure safety of said
occupant in said vehicle.
2. The system as claimed in claim 1, wherein said sensing unit senses said predefined parameter from at least one of a seat belt, a parking brake, a door ajar and a seat belt buckle switch.
3. The system as claimed in claim 2, wherein said sensing unit includes a seat belt sensor (20) to sense said predefined value including said seat belt wearing by said occupant, a parking brake sensor (30) to sense disengagement of parking brake, a door ajar sensor (40) to sense complete door closure, and a seat belt buckle switch sensor (60) to sense engagement of a buckle clip from a holder.

4. The system as claimed in claim 1, wherein said sensing unit includes a speed sensor (50) to sense speed of said vehicle.
5. The system as claimed in claim 1, wherein said control unit receives signal from a seat belt length measurement transducer (70) configured to measure length of a seat belt pulled out from its engagement.
6. The system as claimed in claim 5, wherein said control unit (80) compares length of said seat belt pulled as measured by said seat belt length measurement transducer (70) with a predefined length to confirm engagement of said seat belt.
7. The system as claimed in claim 1, wherein said occupant detection unit (10) detects number of occupants and their position in said vehicle and transmitted signal to said control unit (80).
8. The system as claimed in claim 4, wherein said control unit (80) compares speed of said vehicle sensed by said speed sensor (50) and compares with said threshold speed, and instructs said ECU (90) to lower speed when said sensed present value of said predefined parameter sensed by said sensing unit differs from said predefined value of said predefined parameter.
9. The system as claimed in claim 8, wherein said ECU (90) allows increasing speed of said vehicle above said threshold speed when sensed present value of said predefined parameter sensed by said sensing unit becomes equal from said predefined value of said predefined parameter.

10. The system as claimed in claim 1, wherein said control unit includes a bypass feature to bypass speed control to said threshold speed.