FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION (See section 10, rule 13)
“METHOD, APPARATUS AND SYSTEM FOR ESTIMATING AN ANGULAR POSITION OF A VEHICLE”
MINDA INSTRUMENTS LIMITED, an Indian company, of Gut No. 287, 291-295,298,285/1,286/1 Nanekarwadi, Chakan, Tal khed, Pune-410501, Maharashtra,
India
The following specification particularly describes the invention and the manner in which it is
to be performed.

TECHNICAL FIELD [001] The present disclosure generally relates to controlling a vehicle. Particularly, the present disclosure relates to techniques for determining an angular position of a steering wheel in a vehicle using wheel and vehicle speed/velocity sensors.
BACKGROUND [002] Primary function of a steering wheel is to control a direction of a vehicle relative to a substantially straight path. Today most of the high-end vehicles (e.g., luxury cars) are provided with a steering angle sensor located within a steering column. The steering angle sensor determines the angular position (or rotation) of the steering wheel of the vehicle relative to a neutral position. The neutral position corresponds to the position of the steering wheel and the steering angle sensor when the vehicle travels along a substantially straight path.
[003] To provide assistance to vehicle drivers, modern high-end vehicles are provided with innovative features. One such innovative feature is providing static bending lights. Static bending lights are intended to eliminate blind spots for a driver when making a turn. Static bending lights provide illumination for blind spots by projecting light in a direction of rotation of the steering wheel thereby providing greater visibility to vehicle drivers in the blind spots. The static bending lights assist the driver in detecting the presence of obstacles (e.g., other vehicles, walker) near the blind spots.
[004] Generally, a static bending light refers to a lighting system which turns on when the steering wheel is turned to either the left or right at an angle of more than preset degrees. The turning of the steering wheel is detected with the help of the steering angle sensor which provides a direct reading of the steering wheel indicating a driver’s intention about turning the vehicle around a corner (i.e., whether the driver wants to turn the vehicle left or right).
[005] However, the static bending feature is usually provided only in high end vehicles because for commercial vehicles and low-end vehicles (e.g., cars), the steering angle sensor may not be available on-board unless electrically assisted steering or electronic stability

program features are provided for those vehicles. One more reason for not providing the static bending feature in low-end vehicles is that the components (e.g., the steering angle sensor) used for static bending assembly are expensive. Thus, there exists a need for technology that provides proper estimate of the angular position of the steering wheel in a cost-effective manner so that static bending light assembly in vehicles (specifically in low-end vehicles) can be provided.
[006] Further, for vehicles which are equipped with the steering angle sensor, sometimes the steering angle sensor assembly may fail due to any reason, which increases the probability of accidents while turning the vehicle during night. Thus, there exists a need for technology that facilitates exact estimate of angular position of the steering wheel for smooth functioning of the static bending feature (which is safety-critical for vehicle while turning at corners during night) during the failure of steering angle sensor.
[007] The present disclosure proposes techniques that solve at least the above-mentioned problems and overcome the disadvantages or difficulties of existing vehicles systems and/or techniques associated therewith.
[008] The information disclosed in this background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.
SUMMARY [009] One or more shortcomings discussed above are overcome, and additional advantages are provided by the present disclosure. Additional features and advantages are realized through the techniques of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered a part of the disclosure.
[0010] In an aspect, the present disclosure relates to a method for estimating an angular position of a vehicle. The method may include determining an inner front wheel angular

velocity (Wi) and an outer front wheel angular velocity (Wo) of the vehicle using a plurality of wheel velocity sensors. Further, the method may include determining a velocity (V) of the vehicle using a vehicle velocity sensor. Furthermore, the method may include determining a steering angle (θ) of the vehicle based on the inner front wheel angular velocity (Wi), the outer front wheel angular velocity (Wo), and the velocity (V) of the vehicle. Moreover, the method may include estimating the angular position of the vehicle based on the determined steering angle of the vehicle. The inner front wheel angular velocity (Wi) corresponds to the left front wheel of the vehicle and the outer front wheel angular velocity (Wo) corresponds to right front wheel of the vehicle or vice-versa.
[0011] In an exemplary embodiment of the present disclosure, the method may include activating static bending of head lights of the vehicle if the steering angle is determined to be exceeded than a predefined threshold. Furthermore, the method may include determining a difference between the inner front wheel angular velocity (Wi) and the outer front wheel angular velocity (Wo). The difference between the inner front wheel angular velocity (Wi) and the outer front wheel angular velocity (Wo) indicates turning of the vehicle. Further, the difference between the inner front wheel angular velocity (Wi) and the outer front wheel angular velocity (Wo), if results in approximate zero value, indicates that the vehicle is moving in a straight direction.
[0012] In another exemplary embodiment of the present disclosure, wherein the inner front wheel velocity (Vi) is calculated as:
��∗�� = ��= �� ∗ �
where, Rw: radius of a wheel (which is same for all wheels), Wi: angular velocity of inner front wheel,
Ri: radius of turn as experienced by the inner wheel which might be left front wheel or right front wheel depending on left turn or right turn,
Vi: the inner front wheel velocity or linear speed of the inner wheel (left front wheel or right front wheel),

θ : steering angle, and � : time.
[0013] In yet another exemplary embodiment of the present disclosure, the outer front wheel velocity (Vo) is calculated as:
��∗�� = ��= �� ∗ � �
where, Rw: radius of a wheel (which is same for all wheels), Wo: angular velocity of outer front wheel,
Vo: the outer front wheel velocity or linear speed of the outer wheel (left front wheel or right front wheel),
Ro: radius of turn as experienced by the outer wheel which might be left front wheel or right front wheel depending on left turn or right turn, θ : Steering angle, and t : Time.
[0014] In yet another embodiment of the present disclosure, the velocity (V) of the vehicle is calculated as:
� = �^
where, R: turning radius of the vehicle,
V: Velocity of vehicle or reading of vehicle velocity sensor, θ : Steering angle, and t : time
[0015] In yet another embodiment of the present disclosure, the turning radius (R) is calculated as:
�= 2� ∗ �
(��)2 ∗ �� (�� - ��)
where, Rw: radius of a wheel (which is same for all wheels),
Wi: inner front wheel angular velocity,
R: turning radius of the vehicle,

Wo: outer front wheel angular velocity,
V: speed of vehicle or reading of vehicle velocity sensor,
θ : steering angle, and
t : time.
[0016] In another aspect, the present disclosure relates to an apparatus for estimating the angular position of the vehicle. The apparatus includes the plurality of wheel velocity sensors, the vehicle velocity sensor, and a processor. Further, the processor is coupled to the plurality of wheel velocity sensors and the vehicle velocity sensor. The processor is configured to determine the inner front wheel angular velocity (Wi) and the outer front wheel angular velocity (Wo) of the vehicle. Further, the processor is configured to determine the velocity (V) of the vehicle. Furthermore, the processor is configured to determine the steering angle (θ) of the vehicle based on the inner front wheel angular velocity (Wi), the outer front wheel angular velocity (Wo) and the velocity (V) of the vehicle. Moreover, the processor is configured to estimate the angular position of the vehicle based on the determined steering angle of the vehicle.
[0017] In an exemplary embodiment of the present disclosure, the processor is configured to activate static bending of head lights of the vehicle if the steering angle is determined to be exceeded than the predefined threshold. Furthermore, the processor is configured to determine the difference between the inner front wheel angular velocity (Wi) and the outer front wheel angular velocity (Wo). The difference between the inner front wheel angular velocity (Wi) and the outer front wheel angular velocity (Wo) indicates turning of the vehicle. Further, the difference between the inner front wheel angular velocity (Wi) and the outer front wheel angular velocity (Wo), if results in approximate zero value, indicates that the vehicle is moving in the straight direction.
[0018] In another exemplary embodiment of the present disclosure, wherein the inner front wheel velocity (Vi) is calculated as:
��∗�� = ��= �� ∗ �

where, Rw: radius of a wheel (which is same for all wheels),
Wi: inner front wheel angular velocity,
Ri: radius of turn as experienced by the inner wheel which might be left front wheel or right front wheel depending on left turn or right turn,
Vi: the inner front wheel velocity or linear speed of the inner wheel (left front wheel or right front wheel),
9: steering angle, and
t: time.
[0019] In yet another exemplary embodiment of the present disclosure, the outer front wheel velocity (Vo) is calculated as:
Wo*Rw = Vo= ^^
where, Rw: radius of a wheel (which is same for all wheels), Wo: outer front wheel angular velocity,
Vo: the outer front wheel velocity or linear speed of the outer wheel (left front wheel or right front wheel),
Ro: radius of turn as experienced by the inner front wheel, 9 : Steering angle, and t : Time.
[0020] In yet another embodiment of the present disclosure, the velocity (V) of the vehicle is calculated as:
v = R^
where, R: turning radius of the vehicle,
V: Velocity of vehicle or reading of vehicle velocity sensor, 9 : Steering angle, and t : time
[0021] In yet another embodiment of the present disclosure, the turning radius (R) is

calculated as:
«_ ^!H
(Rw)2 * Wo (Wo - Wi) where, Rw: radius of a wheel (which is same for all wheels), Wi: inner front wheel angular velocity, R: turning radius of the vehicle, Wo: outer front wheel angular velocity, V: speed of vehicle or reading of vehicle velocity sensor, 9: steering angle, and t : time.
[0022] In yet another aspect, the present disclosure relates to a system for estimating the angular position of the vehicle. The system includes the plurality of wheel velocity sensors, the vehicle velocity sensor, and an electronic control unit (ECU). The plurality of wheel velocity sensors is configured to determine the inner front wheel angular velocity (Wi) and the outer front wheel angular velocity (Wo) of the vehicle. The inner front wheel angular velocity (Wi) corresponds to the left front wheel of the vehicle and the outer front wheel angular velocity (Wo) corresponds to right front wheel of the vehicle or vice-versa. The vehicle velocity sensor is configured to determine the velocity (V) of the vehicle. The electronic control unit (ECU) configured to determine the steering angle (9) of the vehicle based on the inner front wheel angular velocity (Wi), the outer front wheel angular velocity (Wo), and the velocity (V) of the vehicle.
[0023] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.
OBJECTIVES
[0024] The main object of the present disclosure is to determine an angular position of a steering wheel in a vehicle without any steering angle sensor.

[0025] Another object of the present disclosure is providing static bending feature in low end vehicles.
[0026] Another object of the present disclosure is to facilitate smooth functioning of the static bending feature during the failure of steering angle sensor.
[0027] Another main object of the present disclosure is to provide maximum illumination in curves and intersections while driving a vehicle, thereby, improving visibility for a vehicle driver during night.
BRIEF DESCRIPTION OF DRAWINGS [0028] Further aspects and advantages of the present disclosure will be readily understood from the following detailed description with reference to the accompanying drawings. Reference numerals have been used to refer to identical or functionally similar elements. The figures together with a detailed description below, are incorporated in and form part of the specification, and serve to further illustrate the embodiments and explain various principles and advantages, in accordance with the present disclosure wherein:
[0029] Figure 1A illustrates an exemplary geometry of a vehicle employing Ackerman steering principle for estimating the angular position of a steering wheel of the vehicle, in accordance with some embodiments of the present disclosure.
[0030] Figure 1B illustrates an exemplary interactive environment for the vehicle employing Ackerman steering principle for estimating the angular position of a steering wheel of the vehicle of Figure 1A, in accordance with some embodiments of the present disclosure.
[0031] Figure 2 illustrates an exemplary block diagram of a vehicle sub-system, in accordance with some embodiments of the present disclosure.

[0032] Figure 3 shows geometry illustration 300 for determining the angular position of the steering wheel of the vehicle, in accordance with an embodiment of the present disclosure.
[0033] Figure 4 illustrates a flow chart of an exemplary method 400 for estimating the angular position of the steering wheel of the vehicle, in accordance with some embodiments of the present disclosure.
[0034] It should be appreciated by those skilled in the art that any block diagrams herein represent conceptual views of illustrative systems embodying the principles of the present subject matter. Similarly, it will be appreciated that any flow charts, flow diagrams, state transition diagrams, pseudo code, and the like represent various processes which may be substantially represented in computer readable medium and executed by a computer or processor, whether or not such computer or processor is explicitly shown.
DETAILED DESCRIPTION [0035] Referring now to the drawings, there is shown an illustrative embodiment of the disclosure “method, apparatus and system for estimating an angular position of a vehicle ”. It is understood that the disclosure is susceptible to various modifications and alternative forms; specific embodiments thereof have been shown by way of example in the drawings and will be described in detail below. It will be appreciated as the description proceeds that the disclosure may be realized in different embodiments.
[0036] The terms “comprises”, “comprising”, or any other variations thereof, are intended to cover a non-exclusive inclusions, such that a setup, device that comprises a list of components that does not include only those components but may include other components not expressly listed or inherent to such setup or device. In other words, one or more elements in a system or apparatus proceeded by “comprises… a” does not, without more constraints, preclude the existence of other elements or additional elements in the system or apparatus or device. It could be noted with respect to the present disclosure that the terms like “a system for remotely detecting lock status of a vehicle”, “The system” refers

to the same system which is used using the present disclosure.
[0037] In the present document, the word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any embodiment or implementation of the present subject matter described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.
[0038] While the disclosure is susceptible to various modifications and alternative forms, specific embodiment thereof has been shown by way of example in the drawings and will be described in detail below. It should be understood, however, that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternative falling within the scope of the disclosure.
[0039] The terms like “wheel speed” and “wheel velocity” may be used interchangeably throughout the description. Further, the terms like “vehicle speed” and “vehicle velocity” may be used interchangeably throughout the description.
[0040] In the following detailed description of the embodiments of the disclosure, reference is made to the accompanying drawings that form a part hereof, and in which are shown by way of illustration specific embodiments in which the disclosure may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the disclosure, and it is to be understood that other embodiments may be utilized and that changes may be made without departing from the scope of the present disclosure. The following description is, therefore, not to be taken in a limiting sense.
[0041] As discussed earlier in the background section, to eliminate blind spots for a driver while making a turn, some vehicles are provided with static bending lights. The static bending lights rely on data from a steering angle sensor for determining whether the driver is making a turn or not and if making the turn, whether he is turning the vehicle left or right relative to a neutral position (or a substantial straight line path). The steering angle sensor is positioned within a steering system of the vehicle so as to detect steering input provided by

the driver.
[0042] However, for many commercial vehicles and low-end or low-cost vehicles the steering angle sensor may not be available on-board. One possible reason for not providing the steering angle sensor is the cost associated with the steering angle sensor. However, Anti-lock Braking System (ABS) is mandatory for almost all commercial vehicles and low-end vehicles. These vehicles have on-board wheel speed sensors apart from vehicle speed sensors. The present disclosure utilizes the wheel speed sensor(s) and vehicle speed sensor(s) for estimating vehicle motion profile (i.e., determining the angular position of a steering wheel of the vehicle) in the event of turning around a corner.
[0043] Thus, the present disclosure overcomes the above-mentioned problems by determining the angular position of the steering wheel of the vehicle in a reliable, simple, and cost effective manner (i.e., without using the steering angle sensor). This way the present disclosure facilitates provisioning of the static bending lights in commercial and low-end vehicles which do not have the steering angle sensor. For the vehicles which are equipped with the steering angle sensor, the present disclosure provides alternate fall back technique in case of failure of the steering angle sensor. Thus, facilitating smooth functioning of static bending feature (which is safety-critical for vehicle turning at corners during night) even in case of failure of steering angle sensor.
[0044] Most of the vehicles today employ the Ackerman steering principle. Referring to Figure 1A, which shows an exemplary geometry 100 of a vehicle employing Ackerman steering principle for determining the angular position of a steering wheel of the vehicle, in accordance with some embodiments of the present disclosure. In an exemplary embodiment of the present disclosure, the vehicle may be a four-wheeler vehicle or multi-wheeled vehicle. The four wheeler vehicle comprises two front wheels 102, 104 and two rear wheels 106, 108. The front wheels 102, 104 may be connected using an axle or axis A-B and the rear wheels 102, 104 may be connected using an axis C-D. The front axle A-B and rear axle C-D may be spaced apart from each other by a distance P-P’.

[0045] The intention of Ackerman principle is to avoid the need for tires to slip sideways when following a path around a curve or when taking a turn. According to Ackerman geometry 100, the inner front wheel 102 and the outer front wheel 104 make different angles while turning, as shown in Figure 1A. In an exemplary embodiment, the inner front wheel 102 may be a left front wheel and the outer front wheel 104 may be a right front wheel. In another embodiment, the inner front wheel 102 may be a right front wheel and the outer front wheel 104 may be a left front wheel. This enables turning radii of both front and rear wheel to meet at the common center point O. The inner wheel 102 travels at a slower speed than the outer wheel 104. The Ackermann principle allows for the rear wheels to have no slip angle, which requires that the center point O lies on a straight line defined by the rear wheels’ axis C-D. This facilitates smooth turning of all the wheels without any wheel slipping, thereby minimizing tire wear.
[0046] As can be seen from Figure 1A, the inner front wheel 102 turns with a larger angle compared to the outer front wheel 104. Assuming that the distance P-P’ between the front axle A-B and rear axle C-D is denoted as wheel base ‘L’; the distance between center line of front and rear wheels (or the axle length) is denoted as ‘T’; and the radius of turn as experienced by the centerline of the vehicle is denoted as R Further, assuming that the angle of inner wheel 102 relative to the neutral position is denoted as αi and the angle of the outer wheel 104 relative to the neutral position is denoted as αo. Consider that Ri is the radius of turn as experienced by the inner front wheel 102 and Ro is the radius of turn as experienced by the outer front wheel 104.
[0047] Assuming ideal conditions (e.g., constant speed, no external force, no body roll or suspension effects), the values of angles αi and αo may be calculated using simple trigonometry as follows:
�� = ���-i(�_\ (1)
R-�

�� = ���'11 -� ) (2)
As can be seen from the above equations, for the same values of L and T, the value of αi is greater than the value of αo.
[0048] Referring to Figure 1B, which shows an exemplary interactive environment for the vehicle employing Ackerman steering principle for estimating the angular position of the steering wheel of the vehicle of Figure 1A, in accordance with some embodiments of the present disclosure. Figure 1B is explained in conjunction with Figure 1A. Referring to Figure 1B, a user 108 is driving the multi-wheeled vehicle. Particularly, user 108 is turning a steering 110 of the vehicle while making a turn. In an exemplary embodiment, the user 108 may be any person or driver. While turning the vehicle, an electronic control unit (not shown) installed within the vehicle may be configured to measure the steering angle of the vehicle. A skilled may understand that Figure 1B depicts only an exemplary scenario, where the estimation of angular position of the steering wheel is required and accordingly static bending features should be enabled. However, there may be other scenario exists which are not captured in the disclosure. The main purpose of providing such scenario is to convey smooth turning of all the wheels without any wheel slipping, thereby providing safety feature with minimized tire wear.
[0049] It may be noted here that the subj ect matter of some or all embodiments described with reference to Figure 1A may be relevant for the description of Figure 1B and the same is not repeated for the sake of brevity.
[0050] Referring now to Figure 2, which is a block diagram 200 of a vehicle sub-system or vehicle 202, in accordance with some embodiments of the present disclosure. Figure 2 is explained in conjunction with Figure 1A and 1B. According to an embodiment of the present disclosure, the vehicle sub-system 202 may comprise the electronic control unit having at least one memory 210 and at least one processor 204 communicatively coupled with a plurality of wheel speed sensor 206, at least one vehicle speed sensor 208, and light

assembly 212, various other components 214. The other components 214 may include a power supply block, a transceiver, a command module etc. The lightening assembly 212 may be a static bending lightning assembly which may be controlled by the processor 204.
[0051] The plurality of wheel velocity sensors 206 are an integral part of modern Anti-lock Braking Systems (ABSs). Since all the wheels do not turn at the same speed, the plurality of wheel velocity sensors 206 detect the rotational wheel speed of vehicles (measured in terms of revolutions per minute (RPM)) and report the detected speeds of all the four wheels to the electronic control unit (ECU) via one or more interface (e.g., Controller Area Network (CAN) interface). In the present disclosure, it is assumed that the at least one processor 204 serves the purpose of ECU.
[0052] In one non-limiting embodiment, at least one vehicle velocity sensor 208 may measure actual speed of the vehicle 100 in terms of distance travelled per unit time (e.g., in terms of m/s or km/s) and report the measured speed to the processor 204. The wheel velocity sensor 206 is different than the vehicle velocity sensor 208 as its job is to record the actual wheel speed in RPM.
[0053] The processor 204 may include, but not restricted to, a general-purpose processor, a Field Programmable Gate Array (FPGA), an Application Specific Integrated Circuit (ASIC), a Digital Signal Processor (DSP), microprocessors, microcomputers, micro-controllers, central processing units, state machines, logic circuitries, and/or any devices that manipulate signals based on operational instructions. A processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.
[0054] The memory 210 may include a Random-Access Memory (RAM) unit and/or a non-volatile memory unit such as a Read Only Memory (ROM), optical disc drive, magnetic disc drive, flash memory, Electrically Erasable Read Only Memory (EEPROM), a memory space on a server or cloud and so forth. Memory 210 may store various types of data (e.g.,

sensor readings) and computer executable instructions.
[0055] In following paragraphs, the present disclosure describes techniques for estimating vehicle motion profile (i.e., determining the angular position of a steering wheel of the vehicle) in the event of turning around a corner using wheel speed sensor(s) and vehicle speed sensor(s).
[0056] Referring now to Figures 3, which illustrate geometry illustration 300 for determining the angular position of the steering wheel of the vehicle, in accordance with some embodiments of the present disclosure. Figure 3 is explained in conjunction with Figures 1A-2. Considering the scenario where the vehicle is turning around a corner. Suppose:
θ: turning angle
R: turning radius
Ri: radius of turn as experienced by the inner wheel which might be left front wheel
or right front wheel depending on left turn or right turn
Ro: radius of turn as experienced by the outer wheel which might be left front wheel or right front wheel depending on left turn or right turn
The values of Ri and Ro may be calculated as follows:
*°=^ <4>
Rw: radius of a wheel (which is same for all wheels) Wi: inner front wheel 102 angular velocity (or rotational speed) Wo: outer front wheel 104 angular velocity (or rotational speed) Vi: inner front wheel velocity or linear speed of the inner wheel 102 Vo: outer front wheel velocity or linear speed of the outer wheel 104 V: Speed of vehicle or reading of vehicle speed sensor

In general, rotational speed and linear speed satisfy following equations:
� = - (5)
where, W is the rotational speed, θ is the angle of rotation expressed in radians, and t is the time to complete the rotation; and
� = — = �.� (6)
where, V is the linear speed and r is radius.
[0057] When the vehicle is moving in a straight line, the rotational speed of inner front wheel (Wi) [i.e., inner front wheel angular velocity] is same as that of outer front wheel (Wo) i.e., Wi=Wo. This indicates that no wheel is turned, and the vehicle is moving in straight line. However, when the vehicle is turning, the inner front wheel 102 angular velocity is less than the outer front wheel 104 angular velocity. Further, during the straight-line motion, the linear speeds of inner front wheel and outer front wheel is same as the speed of vehicle i.e., Vi=Vo=V. The values of Wi, Wo, and V can be obtained from the wheel velocity sensors and vehicle velocity sensor provided in the vehicle.
[0058] To figure out the direction and angle of turning, it is required to find the direction of a tangent to the turning circle (see Figure 3). The following steps are performed to attain this goal. Assuming that entire vehicle of Figure 1 makes angle θ with the horizontal (as seen in Figure 3, where point Q is the vehicle of Figure 1) as governed by the center of turning and turning radius R. This happens when the vehicle turns through the angle θ.
[0059] In one non-limiting embodiment of the present disclosure, at least one processor 204 may determine the angular velocities (Wi and Wo) of inner and outer wheels using the readings from the plurality of wheel velocity sensors 206. The inner front wheel angular velocity (Wi) corresponds to the left front wheel of the vehicle and the outer front wheel angular velocity (Wo) corresponds to right front wheel of the vehicle or vice-versa. If the wheel angular velocities (Wi and Wo) of inner and outer wheels are identical on an average,

then this indicates that the vehicle is not turning, and it is going straight ahead. For instance, the difference between the inner front wheel angular velocity (Wi) and the outer front wheel angular velocity (Wo), if results in approximate zero value, indicates that the vehicle is moving in a straight direction. However, if wheel angular velocities are differing from each other by more or less constant magnitude, the vehicle is likely to be turning. The wheel with lesser wheel angular velocity may be treated as inner front wheel 102 and the one with larger wheel angular velocity may be treated as outer front wheel 104. This way at least one processor 204 may determine the direction of turning.
[0060] In an embodiment of the present disclosure, the at least one processor 204 is configured to determine a steering angle (θ) of the vehicle based on the inner front wheel angular velocity (Wi), the outer front wheel angular velocity (Wo) and the velocity (V) of the vehicle. Based on the determined steering angle of the vehicle, at least one processor 204 is configured to estimate the angular position of the vehicle.
[0061] For instance, at least one processor 204 may compare both wheel angular velocities (Wi and Wo) with vehicle velocity (V) as obtained from vehicle velocity sensor 208. All the three velocities (Wi, Wo, and V) need to follow below relationships:
Inner front wheel velocity (measured by inner wheel speed sensor) follows:
��∗�� = ��= �� ∗ � (7)
Outer front wheel velocity (measured by outer wheel speed sensor) follows:
��∗�� = ��= �� ∗ � (8)
Vehicle velocity (measured by vehicle speed sensor) follows:

� = �^ (9)
Dividing equation (8) by (7):
�� = �� = � (10)
Dividing equation (8) by (9):
� = � =� (11)
Applying Pythagoras theorem in Figure 1,
Ri2 = (R-T/2) 2 + L2 (12)
Ro2 = (R+T/2) 2 + L2 (13)
Subtracting equation (12) from (13):
Ro2 - Ri2 = (R+T/2) 2 - (R-T/2) 2 = 2RT (14)
Substituting equations (10) and (11) into (14):
Ro2 - (Ro/k)2 = 2(Ro/m)T Ro (1-1/k) = (2/m) T
Ro = [2k/m(k-1)] T (15)
This way the value of Ro can be calculated. The value of Ro may be put into equations (10) and (11) to determine the values of R and Ri. For example, R can be computed as follows:

«- 2Illl
(Rw)2 * Wo (Wo - Wi)
[0062] Angle 9 is zero as the outer front wheel angular velocity is same as the inner front wheel angular velocity. It may be counted from zero onwards as vehicle starts turning. Vehicle turning is sensed when inner wheel and outer wheel angular velocities start differing as discussed above. Since R is known as derived above, RB is known (from equation (9)) though vehicle speed sensor pulse counting (every pulse represents a distance traveled in linear fashion). Hence, 9 can be computed here as follows:
_ (Rw)2 * Wo (Wo -Wi)*t
6 ~ W7T
[0063] Angle 9 indicates the vehicle turning angle/direction traversed at a circle with radius R. With this vehicle’s turning movement can be accurately estimated. Once the turning angle or steering angle is determined, any conventional known technique may be used to control static bending of lights based on the determined angle 9. In an aspect, the static bending is activated only after determining that the angle 9 exceeds a threshold amount.
[0064] This way the present disclosure facilitates provisioning of the static bending lights in commercial and low-end vehicles which do not have the steering angle sensor. For the vehicles which are equipped with the steering angle sensor, the present disclosure provides alternate fallback technique in case of failure of the steering angle sensor. Thus, facilitating smooth functioning of static bending feature (which is safety-critical for vehicle turning at corners during night) even in case of failure of steering angle sensor.
[0065] Referring now to Figure 4 which depicts a flowchart illustrating method 400 for estimating the angular position of the steering wheel of the vehicle, in accordance with some embodiments of the present disclosure. The method 400 is merely provided for exemplary purposes, and embodiments are intended to include or otherwise cover any methods or

procedures for determining the angular position of the steering wheel of the vehicle.
[0066] The method 400 may include, at block 402, determining an inner front wheel angular velocity (Wi) and an outer front wheel angular velocity (Wo) of the vehicle using a plurality of wheel velocity sensors 206. In an embodiment of the present disclosure, the inner front wheel angular velocity (Wi) corresponds to left front wheel of the vehicle and the outer front wheel angular velocity (Wo) corresponds to right front wheel of the vehicle or vice-versa.
[0067] At block 404, the method 400 may include determining the velocity (V) of the vehicle using the vehicle velocity sensor 208.
[0068] At block 406, the method 400 may include the steering angle (θ) of the vehicle based on the inner front wheel angular velocity (Wi), the outer front wheel angular velocity (Wo), and the velocity (V) of the vehicle.
[0069] At block 408, the method 400 may estimate the angular position of the vehicle based on the determined steering angle of the vehicle.
[0070] Further, the method may include activating static bending of head lights of the vehicle if the steering angle is determined to be exceeded than a predefined threshold. Furthermore, the method includes determining a difference between the inner front wheel angular velocity (Wi) and the outer front wheel angular velocity (Wo). The difference between the inner front wheel angular velocity (Wi) and the outer front wheel angular velocity (Wo) indicates turning of the vehicle. Further, the difference between the inner front wheel angular velocity (Wi) and the outer front wheel angular velocity (Wo), if results in approximate zero value, indicates that the vehicle is moving in a straight direction.
[0071] The above method 400 may be described in the general context of computer executable instructions. Generally, computer executable instructions can include routines, programs, objects, components, data structures, procedures, modules, and functions, which perform specific functions or implement specific abstract data types.

[0072] It may be noted here that the subject matter of some or all embodiments described with reference to Figures 1-3 is relevant for the method as well and the same is not repeated for the sake of brevity.
[0073] Furthermore, one or more computer-readable storage media may be utilized in implementing embodiments consistent with the present disclosure. A computer-readable storage medium refers to any type of physical memory on which information or data readable by a processor may be stored. Thus, a computer-readable storage medium may store instructions for execution by one or more processors, including instructions for causing the processor(s) to perform steps or stages consistent with the embodiments described herein. The term “computer-readable medium” should be understood to include tangible items and exclude carrier waves and transient signals, i.e., non-transitory. Examples include Random Access Memory (RAM), Read-Only Memory (ROM), volatile memory, nonvolatile memory, hard drives, Compact Disc (CD) ROMs, Digital Video Disc (DVDs), flash drives, disks, and any other known physical storage media.
[0074] Certain aspects may comprise a computer program product for performing the operations presented herein. For example, such a computer program product may comprise a computer readable media having instructions stored (and/or encoded) thereon, the instructions being executable by one or more processors to perform the operations described herein. For certain aspects, the computer program product may include packaging material.
[0075] The terms “including”, “comprising”, “having” and variations thereof mean “including but not limited to”, unless expressly specified otherwise.
[0076] The terms like “plurality” and “one or more” may be used interchangeably or in combination throughout the description.
[0077] The terms like “vehicle”, “four-wheeler vehicle”, and “multi wheeled vehicle” may be used interchangeably or in combination throughout the description.
[0078] The foregoing description of the various embodiments is provided to enable any

person skilled in the art to make or use the present disclosure. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the disclosure. Thus, the present disclosure is not intended to limit the embodiments shown herein, and instead the embodiments should be accorded the widest scope consistent with the principles and novel features disclosed herein.

We Claim:
1. A method for estimating an angular position of a vehicle, the method comprising:
determining an inner front wheel angular velocity (Wi) and an outer front wheel angular velocity (Wo) of the vehicle using a plurality of wheel velocity sensors, wherein the inner front wheel angular velocity (Wi) corresponds to left front wheel of the vehicle and the outer front wheel angular velocity (Wo) corresponds to right front wheel of the vehicle or vice-versa;
determining a velocity (V) of the vehicle using a vehicle velocity sensor;
determining a steering angle (θ) of the vehicle based on the inner front wheel angular velocity (Wi), the outer front wheel angular velocity (Wo), and the velocity (V) of the vehicle; and
estimating the angular position of the vehicle based on the determined steering angle of the vehicle.
2. The method as claimed in claim 1, further comprising:
activating static bending of head lights of the vehicle if the steering angle is determined to be exceeded than a predefined threshold.
3. The method as claimed in claim 1, further comprising:
determining a difference between the inner front wheel angular velocity (Wi) and the outer front wheel angular velocity (Wo), wherein the difference between the inner front wheel angular velocity (Wi) and the outer front wheel angular velocity (Wo) indicates turning of the vehicle.
4. The method as claimed in claim 3, wherein the difference between the inner front wheel angular velocity (Wi) and the outer front wheel angular velocity (Wo), if results in approximate zero value, indicates that the vehicle is moving in a straight direction.
5. The method as claimed in claim 1, wherein the inner front wheel velocity (Vi) is calculated as:
��∗�� = ��= �� ∗ �
where, Rw: radius of a wheel (which is same for all wheels), Wi: inner front wheel angular velocity,

Ri: radius of turn as experienced by the inner wheel which might be left front wheel or right front wheel depending on left turn or right turn,
Vi: inner front wheel velocity or linear speed of the inner front wheel (left front wheel or right front wheel),
θ : steering angle, and � : time.
6. The method as claimed in claim 1, wherein the outer front wheel velocity (Vo) is calculated as:
��∗�� = ��= �� ∗ �
where, Rw: radius of a wheel (which is same for all wheels), Wo: outer front wheel angular velocity,
Vo: outer front wheel velocity or linear speed of the outer wheel (left front wheel or right front wheel),
Ro: radius of turn as experienced by the outer wheel which might be left front wheel or right front wheel depending on left turn or right turn, θ : Steering angle, and t : Time.
7. The method as claimed in claim 1, wherein the velocity (V) of the vehicle is calculated as:
� = �^
where, R: turning radius of the vehicle,
V: Velocity of vehicle or reading of vehicle velocity sensor, θ : Steering angle, and t : time.
8. The method as claimed in claim 7, wherein the turning radius (R) is calculated as:
�= 2� ∗ �
(��)2 ∗ �� (�� - ��)
where, Rw: radius of a wheel (which is same for all wheels),

Wi: inner front wheel angular velocity,
R: turning radius of the vehicle,
Wo: outer front wheel angular velocity,
V: speed of vehicle or reading of vehicle velocity sensor,
9: steering angle, and
t : time.
9. The method as claimed in claim 8, wherein the steering angle (9) is calculated as:
_ (Rw)2 * Wo (Wo -Wi)*t
where, Rw: radius of a wheel (which is same for all wheels), Wi: inner front wheel angular velocity, Wo: outer front wheel angular velocity,
V: speed of the vehicle or reading of the vehicle velocity sensor, T: distance between center line of front and rear wheels (or the axle length) 9: steering angle, and t: time.
10. An apparatus for estimating an angular position of a vehicle, the apparatus comprising:
a plurality of wheel velocity sensors;
a vehicle velocity sensor; and
a processor coupled to the plurality of wheel velocity sensors and the vehicle velocity sensor,
wherein the processor is configured to:
determine an inner front wheel angular velocity (Wi) and an outer front wheel angular velocity (Wo) of the vehicle, wherein the inner front wheel angular velocity (Wi) corresponds to left front wheel of the vehicle and the outer front wheel angular velocity (Wo) corresponds to right front wheel of the vehicle or vice-versa;
determine a velocity (V) of the vehicle;
determine a steering angle (9) of the vehicle based on the inner front wheel angular velocity (Wi), the outer front wheel angular velocity (Wo) and the velocity (V) of the vehicle; and
estimate the angular position of the vehicle based on the determined steering angle of

the vehicle.
11. The apparatus as claimed in claim 10, wherein the processor is further configured to:
activate static bending of head lights of the vehicle if the steering angle is determined to be exceeded than a predefined threshold.
12. The apparatus as claimed in claim 10, wherein the processor is further configured to:
determine a difference between the inner front wheel angular velocity (Wi) and the outer front wheel angular velocity (Wo), wherein the difference between the inner front wheel angular velocity (Wi) and the outer front wheel angular velocity (Wo) indicates turning of the vehicle.
13. The apparatus as claimed in claim 12, wherein the difference between the inner front wheel angular velocity (Wi) and the outer front wheel angular velocity (Wo), if results in approximate zero value, indicates that the vehicle is moving in a straight direction.
14. The apparatus as claimed in claim 10, wherein the inner front wheel velocity (Vi) is calculated as:
��∗�� = ��= �� ∗ �
where, Rw: radius of a wheel (which is same for all wheels), Wi: inner front wheel angular velocity,
Ri: radius of turn as experienced by the inner wheel which might be left front wheel or right front wheel depending on left turn or right turn,
Vi: inner front wheel velocity or linear speed of the inner wheel (left front wheel or right front wheel),
θ : steering angle, and � : time.

��∗�� = ��= �� ∗ �
where, Rw: radius of a wheel (which is same for all wheels), Wo: outer front wheel angular velocity,
Vo: linear front wheel velocity or linear speed of the outer wheel (left front wheel or right front wheel),
Ro: radius of turn as experienced by the outer wheel which might be left front wheel or right front wheel depending on left turn or right turn, θ : Steering angle, and t : Time.
16. The apparatus as claimed in claim 10, wherein the vehicle velocity (V) is calculated as:
� = �^
where, R: turning radius of the vehicle,
V: Velocity of vehicle or reading of vehicle velocity sensor, θ : Steering angle, and t : time.
17. The apparatus as claimed in claim 16, wherein the turning radius (R) is calculated as:
�= 2�l∗ �
(��)2 ∗ �� (�� - ��) where, Rw: radius of a wheel (which is same for all wheels), Wi: inner front wheel angular velocity, R: turning radius of the vehicle, Wo: Outer front wheel angular velocity, V: Velocity of vehicle or reading of vehicle speed sensor, θ : steering angle, and t : time.
18. The apparatus as claimed in claim 17, wherein the steering angle (θ) is calculated as:

_ (Rw)2 * Wo (Wo -Wi)*t
where, Rw: radius of a wheel (which is same for all wheels), Wi: inner front wheel angular velocity, Wo: outer front wheel angular velocity,
V: Velocity of the vehicle or reading of the vehicle velocity sensor, T: distance between center line of front and rear wheels (or the axle length) 9: steering angle, and t: time.
19. A system for estimating an angular position of a vehicle, the system comprising:
a plurality of wheel velocity sensors configured to determine an inner front wheel angular velocity (Wi) and an outer front wheel angular velocity (Wo) of the vehicle using a plurality of wheel velocity sensors, wherein the inner front wheel angular velocity (Wi) corresponds to left front wheel of the vehicle and the outer front wheel angular velocity (Wo) corresponds to right front wheel of the vehicle or vice-versa;
a vehicle velocity sensor configured to determine a velocity (V) of the vehicle; and
an electronic control unit (ECU) configured to:
determine a steering angle (9) of the vehicle based on the inner front wheel angular
velocity (Wi), the outer front wheel angular velocity (Wo), and the velocity (V) of the
vehicle; and
estimate the angular position of the vehicle based on the determined steering angle of
the vehicle.