DESC:This application is based on and derives the benefit of Indian Provisional Application 201641002589, the contents of which are incorporated herein by reference.

TEHCNICAL FIELD
[001] Embodiments disclosed herein relate to vehicle safety systems and more particularly to crash detection systems in vehicles.

BACKGROUND
[002] Active restraint systems in vehicles utilize one or more sensors to detect the occurrence of a crash in order to deploy air bags or other restraint or occupant protection devices. Sensor signals are sent to an electronic control module that monitors the signals and determines when conditions warrant activation or deployment of an air bag. A number of solutions are available for predicting the occurrence of an accident. Some of these solutions require complex electronics and expensive components.
[003] A first solution uses a crash detection apparatus which includes a crash detection unit and first, second, and third acceleration sensors which are installed at different positions of the object whose crash is to be detected. The crash detection unit calculates expectation acceleration of the third acceleration sensor based on measurement information obtained by the first acceleration sensor and the second acceleration sensor, compares the expectation acceleration with a measured acceleration measured by the third acceleration sensor, and detects whether a shape of the object has been deformed or not.
[004] Another solution uses a device for sensing crashes in a vehicle. The solution uses a mode-determining component, a first detecting component and a second detecting component. The mode-determining component can generate an in-vehicle signal. The first detecting component can detect a first parameter and can generate a first detector signal based on the first detected parameter. The second detecting component can detect a second parameter and can generate a second detector signal based on the second detected parameter. The mode-determining component can further generate a crash mode signal based on the in-vehicle signal, the first detector signal and the second detector signal.
[005] Another solution comprises a vehicular crash sensing system that includes a bumper cap for contacting a bumper. A chamber fits into a side rail attached to the bumper, wherein the bumper cap seals the chamber. A stop element limits movement of the chamber into the side rail. A pressure sensor detects an increased chamber air pressure during crushing of the chamber resulting from movement of the bumper with respect to the stop element.
[006] Another solution comprises a crash detection apparatus, which includes a crash detection unit and three acceleration sensors installed at different positions of the object whose crash is to be detected. The crash detection unit calculates expectation acceleration of the third acceleration sensor based on measurement information obtained by the first acceleration sensor and the second acceleration sensor, compares the expectation acceleration with a measured acceleration measured by the third acceleration sensor, and detects whether a shape of the object has been deformed or not.
[007] Another solution uses a metal plate that is buried in a gasket of a case for accommodating an electric device such as an inverter. The metal plate is connected to a control board in the case, and the voltage of the metal plate is determined. A reference voltage is applied to the metal plate, and the case is grounded. When the metal plate is brought into contact with the case or disconnected due to a crash, the voltage of the metal plate is thereby changed, and the control board detects a crash, based on the change in the voltage.
[008] Another solution discloses an integrated crash and vehicle movement sensing system by use of distributed new multi-axis satellite sensors combining side and/or front/rear crash sensing with other applications requiring dynamic vehicle movement data like (but not limited to) roll and/or pitch detection as well as active suspension, head light beam leveling, etc. is disclosed. Depending on the required functionality, two or more satellite sensor modules are used, which measure multi-axis high-g and low-g acceleration, without needing any further sensor inputs like gyroscopes while achieving a high level of failsafe and redundancy.
[009] The above solutions mainly use the accelerometer, which responds to gravitational forces occurring during deceleration associated with a crash. The accelerometer has a small size, so that it has a minimal effect on the mechanical crash performance of the structures to which it is mounted. In some situations, however, an accelerometer may not perform well because of the nature of the movements of the vehicle structure to which it is mounted both prior to and during a crash. Depending on the transmission of loads, deformation, and other structural issues, certain positions on a vehicle frame wherein an accelerometer might be mounted can be subject to vibrational resonance or other motions that interfere with sensing of the overall vehicle movement. This issue is sometimes addressed by mounting extra struts to the vehicle frame in order to either create an acceptable location for an accelerometer or to modify vibrational resonance in the frame, but such struts may interfere with the intentionally-controlled deformation of vehicle structures during a crash, may be difficult or impossible to package in the available space, or may be too costly. Consequently, other types of crash sensors are also sometimes used. A different type of known crash sensor directly senses an impact. Examples of impact sensors include a moving ball sensor and a deforming chamber sensor. In a deforming chamber sensor, a pressure or temperature of a fluid (e.g., air) in a chamber being compressed or crushed during a crash can be monitored to detect a deformation. Such impact sensors typically have a greater size, so that it may be even harder to find a good packaging space with sufficient clearance. Known uses of deforming chamber sensors have been especially subject to the problem of the creation of unintended changes in the controlled deformation during a crash.

OBJECTS
[0010] The principal object of embodiments disclosed herein is to disclose a low cost crash detection method and system for vehicles.
[0011] Another object of embodiments disclosed herein is to propose a low cost crash detection system for vehicles, wherein the system comprises of a self-diagnosis system.

BRIEF DESCRIPTION OF FIGURES
[0012] This invention is illustrated in the accompanying drawings, through out which like reference letters indicate corresponding parts in the various figures. The embodiments herein will be better understood from the following description with reference to the drawings, in which:
[0013] FIGs. 1a and 1b depict the detector elements present in a vehicle for detecting a crash, according to embodiments as disclosed herein;
[0014] FIGs. 2 depicts an example arrangement of detector elements in a vehicle, according to embodiments as disclosed herein;
[0015] FIG. 3 depicts a plurality of detector elements connected to a control unit, according to embodiments as disclosed herein;
[0016] FIGs. 4a and 4b depict example deployments of the detector elements on a vehicle, according to embodiments as disclosed herein; and
[0017] FIG. 5 depicts the control unit, according to embodiments as disclosed herein.

DETAILED DESCRIPTION
[0018] The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
[0019] The embodiments herein disclose a low cost crash detection method and system for vehicles. Referring now to the drawings, and more particularly to FIGS. 1 through 5, where similar reference characters denote corresponding features consistently throughout the figures, there are shown preferred embodiments.
[0020] Vehicle herein can refer to any powered or un-powered vehicle. Examples of vehicles can be but not limited to cars, vans, trucks, buses, scooters, motorcycles, trains, boats, ships, and so on.
[0021] Crash herein can refer to any type of incident where at least one part of the body of the vehicle can be deformed / damaged in any manner.
[0022] FIGs. 1a and 1b depict the detector elements present in a vehicle for detecting a crash. The detector element 100 comprises of a base element 101, a movable element 102, and a connector element 103. The base element 101 can be connected to at least one of a frame of the vehicle, a portion of the body of the vehicle, a component of the vehicle, or any other suitable portion of the vehicle. The movable element 102 can be connected to the base element 101, using a suitable means such as a spring loaded arrangement. The movable element 102 comprises of a locking element 104. The movable element 102 further comprises of an interrupter element 105. The connector element 103 is located between the base element 101 and the movable element 102. The interrupter element 105 can interrupt a signal flowing through the connector element 103, when energy flows from an object colliding with the vehicle to a vehicle part to which the detector element is attached to the base element 101. In an embodiment herein, the signal flowing through the connector element 103 can be an electrical charge comprising of at least one of carriers of power, carriers of return line analogously also referred to as ground line, analogue signals, digital signals, electrical charge mixed signals, modulated signals, a change in flow of charge in either of directions of electrical charge as carriers of power, carriers of return line analogously referred to as ground line, analogue signals, digital signals, mixed signals, modulated signals, fluids, and combinations thereof. In an embodiment herein, the signal flowing through the connector element 103 can be fluids. In an embodiment herein, the signal flowing through the connector element 103 can be a voltage signal referenced to negative of a battery present in the vehicle.
[0023] Each of the detector elements 100 can detect at least one attribute and generate a state signal. The attributes can depend on the flow through the connector element 103. The attribute can be associated with at least one of voltage levels measured in reference to a common reference, voltage levels measured in reference to a referred reference, change in voltage levels in comparison to a pre-determined threshold value compared as equal to, less than, greater than and combinations thereof, a current level in reference to a common reference, a current level in reference to a referred reference, a change in current level in comparison to a pre-determined value compared as equal to, less than, greater than and combinations thereof, with voltage patterns, which is periodic (or) non-periodic measured in reference to a common reference, with voltage patterns, which is periodic (or) non-periodic measured in reference to a referred reference, with current patterns, which is periodic (or) non-periodic measured in reference to a common reference, with current patterns, which is periodic (or) non-periodic measured in reference to a referred reference, with vehicle supply voltage referenced to a common reference, with vehicle supply voltage referenced to a referred reference, with vehicle return line (or) vehicle ground, with drop in pressure inside the detector element, and with flow of fluids out of the detector element.
[0024] The detector elements 100 can communicate the attributes to a control unit. The detector elements 100 can communicate the attributes to the control unit directly using at least one suitable means such as wired communication means (such as analog signals, digital signals, embedded messaging and so on), wireless communication means or any other equivalent means.
[0025] The detector elements 100 can be connected to at least one power source. The power source can be at least one of a dedicated power source, or an energy source present in the vehicle (such as the battery).
[0026] FIG. 2 depicts an example arrangement of detector elements in a vehicle. In the example depicted herein, the detector elements 100 can be connected in series with each other using the connector element 103. Consider that a collision occurs in the area where the first detector element is connected. The energy from the collision can be transferred to the first detector element. This energy causes the first detector element to move towards the other detector elements (as depicted in FIG. 2). This can interrupt the signal flowing through the connector element 103.
[0027] FIG. 3 depicts a plurality of detector elements connected to a control unit. In the example depicted herein, the detector elements 100 can be connected in series with each other using the connector element 103 and then connected to the control unit 301. The detector elements 100 can be located around the vehicle (as depicted in the example in FIG. 4a) or at specific pre-defined locations around the body (such as the bumper, as depicted in the example in FIG. 4b), such that the detector elements 100 can detect collisions. The number of detector elements 100 can depend on the required crash coverage.
[0028] FIG. 5 depicts the control unit. The control unit 301 can receive attributes from at least one detector element 100. The control unit 301 can also receive data from at least one vehicle system. The control unit 301 can derive a 1st detected signal by comparing a first attribute received from a first detector element with at least one first evaluation criteria. The control unit 301 can derive a 2nd detected signal by comparing a second attribute received from a second detector element with at least one second evaluation criteria. The control unit 301 can derive a state signal from the 1st and 2nd detected signals. The control unit 301 can derive a mode signal from the state signal and at least one signal received from the vehicle systems. In an embodiment herein, the control unit 301 can use AND operations to derive the above mentioned signals. The mode signal can have three states. A first state representing normal operating state of the vehicle. A second state representing a diagnostic state of the vehicle. A third state representing a state where the vehicle has suffered a crash.
[0029] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
,CLAIMS:STATEMENT OF CLAIMS
What is claimed is:
1. A system for detecting a crash in a vehicle, the system comprising of at least one detector element (100) connected to a control unit (301), the control unit (301) configured for
deriving a 1st detected signal from a first attribute received from a detector element (100) and a first evaluation criteria;
deriving a 2nd detected signal from a second attribute received from a detector element (100) and a second evaluation criteria;
deriving a state signal from the 1st detected signal and the 2nd detected signal; and
deriving a mode signal from the state signal and at least one signal from at least one system present in the vehicle.

2. The system, as claimed in claim 1, wherein the detector element (100) comprises of a base element (101), a movable element (102) connected to the base element (101), and a connector element (103) located between the base element (101) and the movable element (102).

3. The system, as claimed in claim 2, wherein the movable element (102) further comprises of a locking element (104) and an interrupter element (105).
4. The system, as claimed in claim 1, wherein the control unit (301) derives the 1st detected signal using an AND operation.

5. The system, as claimed in claim 1, wherein the control unit (301) derives the 2nd detected signal using an AND operation.

6. The system, as claimed in claim 1, wherein the control unit (301) derives the state signal using an AND operation.

7. The system, as claimed in claim 1, wherein the control unit (301) derives the mode signal using an AND operation.

8. The system, as claimed in claim 1, wherein the mode signal is at least one of a
a first state, which represents normal operating state of the vehicle;
a second state representing a diagnostic state of the vehicle; and
a third state representing a state where the vehicle has suffered a crash.