FORM 2
THE PATENTS ACT 1970
[39 OF 1970]
AND
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION [See section 10; rule 13]
TITLE OF THE INVENTION VEHICLE WHEEL MISALIGNMENT DETECTION
APPLICANT(s)
TATA MOTORS PASSENGER VEHICLES LIMITED
an Indian Company Floor 3, 4, Plot-18, Nanavati Mahalaya,
Mudhana Shetty Marg, BSE, Fort, Mumbai City, 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
[0001] The present invention relates to wheels of vehicles, and more specifically, related to detecting misalignment of wheels of the vehicles.
BACKGROUND OF THE INVENTION
[0002] A vehicle, such as a passenger vehicle or a commercial vehicle, may include a plurality of wheels, such as four or more wheels. The wheels are to be properly aligned to ensure that the vehicle does not “pull” to one side when the steering wheel of the vehicle is held without any rotation. Misalignment of the wheels may increase wear of the tyres and may also increase the effort to be exerted by the driver to control the steering wheel.
[0003] Although techniques exist to detect wheel misalignment, such techniques require the use of specialized equipment, and is typically performed at workshops. Further, onboard detection of wheel misalignment (detection of wheel misalignment within the vehicle) generally requires the use of components, such as steering torque assist sensor, lateral accelerometer, and yaw rate sensor, that are otherwise not required in the vehicle. Also, the onboard detection typically requires performance of complex calculations to detect the wheel misalignment. Accordingly, the conventional techniques used for onboard detection of wheel misalignment increase cost of the vehicle.
SUMMARY OF THE INVENTION
[0004] A device for detecting misalignment of a wheel of a vehicle includes a processor and a misalignment detection module executable by the processor. When executed, the misalignment detection module compares current drawn by a motor corresponding to a steering wheel of the vehicle with a reference current value. Based on the comparison, the misalignment detection module detects misalignment.

BRIEF DESCRIPTION OF DRAWINGS
[0005] The features, aspects, and advantages of the subject matter will be better understood with regard to the following description, and accompanying figures. The use of the same reference number in different figures indicates similar or identical features and components.
[0006] Fig. 1 illustrates a device for detecting misalignment of a wheel of a vehicle, according to an implementation of the present subject matter.
[0007] Fig. 2 illustrates the vehicle in which a wheel misalignment can be detected, according to an implementation of the present subject matter.
[0008] Fig. 3 illustrates current bin plots that are usable for detecting misalignment of wheels of a vehicle, according to an implementation of the present subject matter.
[0009] Fig. 4 illustrates a method for detecting misalignment of wheels of a vehicle, according to an implementation of the present subject matter.
[0010] Fig. 5 illustrates various current bin plots for misaligned wheels and for aligned wheels obtained based on various trials, according to an implementation of the present subject matter.
DETAILED DESCRIPTION OF INVENTION
[0011] The present subject matter relates to vehicle wheel misalignment detection. Using techniques of the present subject matter, wheel misalignment can be detected within the vehicle in a cost-effective and efficient manner.
[0012] In accordance with an implementation of the present subject matter, a vehicle includes a steering wheel to control movement of wheels of the vehicle and

a motor corresponding to the steering wheel. The motor may aid in rotation of the wheels based on rotation of the steering wheel. A misalignment detection module in the vehicle may compare a current drawn by the motor with a reference current value. Based on the comparison, the misalignment detection module may detect whether a wheel of the vehicle is misaligned. For example, if a difference between the current drawn and the reference current value is beyond a threshold value, the misalignment detection module may detect that a wheel of the vehicle is misaligned. The detection may be followed by an alert to the driver of the vehicle, such as in the form of a visual alert or an audio alert.
[0013] In an implementation, current drawn may be monitored for a predetermined time window, such as for 30 seconds. Further, the current samples obtained may be categorized into a current range bin of a plurality of current range bins. For example, if the value of a current sample is 1.1 A, the current sample may be categorized into a current range bin of 1-2 A and if the value of a current sample is 2.5 A, the current sample may be categorized into a current range bin of 2-3 A. Such a categorization of each current sample results in the formation of a current bin plot, which indicates the number of samples in each current range bin. The current range bin is compared with a reference current bin. For example, the number of current samples in a 1-2 A current range bin of the current bin plot is compared against the number of current samples in the 1-2 A current range bin of the reference current bin plot. Such a comparison may be repeated for each current range bin. Based on the comparison, the wheel misalignment may be detected.
[0014] In an implementation, prior to performing the comparison, the misalignment detection module may detect if conditions under which misalignment of a wheel can be detected are satisfied. Upon satisfaction of the conditions, the comparison of the current is carried out. The conditions include speed of the vehicle being in a predefined range, pressure of tyres of the vehicle being in a predefined range, the angle of rotation of the steering wheel being in a predefined range, and speed of each wheel of the vehicle being within a predefined range of speed of other wheels of the vehicle.

[0015] The present subject matter provides an accurate technique for detecting misalignment of wheels of a vehicle. Further, the detection of misalignment can be performed without using sensors that are typically not used in the vehicles. That is, additional sensors need not be deployed in a vehicle for implementing the present subject matter. Further, misalignment detection can be performed without performing complex calculations. Thus, the present subject matter provides a simple and a cost-effective technique for onboard vehicle misalignment detection.
[0016] The implementations herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting implementations that are illustrated in the accompanying drawings and detailed in the following description. It should be understood, however, that the following descriptions, while indicating preferred implementations and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the implementations herein without departing from the spirit thereof, and the implementations herein include all such modifications. The examples used herein are intended merely to facilitate an understanding of ways in which the implementations herein can be practiced and to further enable those skilled in the art to practice the implementations herein. Accordingly, the examples should not be construed as limiting the scope of the implementations herein.
[0017] Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the implementations herein. Also, the various implementations described herein are not necessarily mutually exclusive, as some implementations can be combined with one or more other implementations to form new implementations.
[0018] Referring now to the drawings, where similar reference characters denote corresponding features consistently throughout the figures, there are shown preferred implementations. Further, for the sake of simplicity, and without limitation, the same numbers are used throughout the drawings to reference like

features and components. The implementations herein will be better understood from the following description with reference to the drawings.
[0019] Fig. 1 illustrates a device 100 for detecting misalignment of a wheel of a vehicle, according to an implementation of the present subject matter. The vehicle (not shown in Fig. 1) may have a plurality of wheels (not shown in Fig. 1), such as four or more wheels. In an example, the vehicle may be a passenger vehicle, such as a car, or a commercial vehicle, such as a truck. A wheel of a vehicle may become misaligned due to various reasons, such as a heavy impact caused by hitting a boulder, bumping a curb, or a road accident. When a wheel is misaligned, the vehicle tends to pull to one side of the road. For instance, even if a steering wheel (not shown in Fig. 1) is held straight without any rotation, the vehicle may tend to travel leftward or rightward.
[0020] The device 100 may enable detection of a wheel misalignment. The device 100 may be part of the vehicle itself. In an implementation, the device 100 may be a control unit disposed in the vehicle for performing one or more control actions. Accordingly, the device 100 enables performing an onboard wheel misalignment detection.
[0021] The device 100 may include a processor 102 and a memory 104. The processor 102 may be implemented, for example, as microprocessors, microcomputers, microcontrollers, digital signal processors, logic circuitries, and/or any devices that manipulate signals based on operational instructions. The memory 104 may include any non-volatile memory (e.g., EPROM, flash memory, Memristor, etc.) and/or non-transitory computer-readable medium including volatile memory (e.g., RAM). Among other capabilities, the processor 102 may fetch and execute computer-readable instructions included in the memory 104.
[0022] In an implementation, the device 100 may be an electronic control unit (ECU) of the vehicle 100. For example, the device 100 may be an ECU that is to control an electric power assisted system (EPAS) of the vehicle. In accordance with

the example, the device 100 may also be referred to as an EPAS ECU. The EPAS includes an electric motor (not shown in Fig. 1) that aids in movement of the wheel of the vehicle based on rotation of the steering wheel. For instance, the electric motor may provide an additional rotation force for movement of the wheel, in addition to the rotation force exerted on the steering wheel by the driver. The operation of the electric motor, such as supply of current to the electric motor, may be controlled by the EPAS ECU.
[0023] To enable detection of the wheel misalignment, the vehicle 200 includes a misalignment detection module 106, which may monitor the current drawn by the electric motor. The current drawn may be compared with a reference current value. Based on the comparison, the misalignment detection module 106 may detect whether there is a misalignment of the wheel. For example, if the current value differs from the reference current value by more than a threshold amount, the misalignment detection module 106 may determine that the wheel is misaligned.
[0024] Upon determining that the wheel is misaligned, the misalignment detection module 106 may provide an alert to the driver. The alert may be, for example, an audio alert through a loudspeaker in the vehicle or a visual alert through a display in the vehicle. The alert may indicate that one or more wheels of the vehicle are misaligned, and may prompt the driver to get the wheels checked.
[0025] In an implementation, the misalignment detection module 106 may be implemented as software, firmware, hardware, or combinations thereof. In the case of a software implementation, the misalignment detection module 106 may represent program code that performs specified tasks when executed on the processor 102. The program code can be stored in one or more computer readable memory devices, such as the memory 104.
[0026] Fig. 2 illustrates the vehicle 200 in which a wheel misalignment can be detected, according to an implementation of the present subject matter. The vehicle 200 may include a plurality of wheels, such as a front left wheel 202 and a front

right wheel 204. In addition, the vehicle 200 may include other wheels, such as rear left wheel and rear right wheel (not shown in Fig. 2). The vehicle 200 may include a steering wheel 206 that can be rotated by the driver of the vehicle 200 for controlling the leftward and rightward movement of the wheels. The rotational force exerted on the steering wheel 206 may be augmented by a steering wheel motor 208 (hereinafter referred to as the motor 208). The operation of the motor 208 may be controlled by an EPAS ECU 210.
[0027] As explained earlier, the EPAS ECU 210 may implement the misalignment detection module 106 (not shown in Fig. 2). Further, as explained earlier, the misalignment detection module 106 may compare the current drawn by the motor 208 with a reference current value, and may detect the misalignment based on the comparison.
[0028] In an implementation, prior to comparing current drawn by the motor 208 with the reference current value, the misalignment detection module 106 may determine if conditions under which a misalignment can be detected are satisfied. Upon satisfaction of the conditions, the comparison, and consequently, the detection of wheel misalignment, may be performed. The satisfaction of the conditions ensures that the current drawn by the motor 208 is a reliable indicator of wheel misalignment. Thus, false positives in the detection of wheel misalignment are prevented.
[0029] In an example, the conditions under which a misalignment can be detected include (i) speed of the vehicle 200 being in a predefined speed range, (ii) pressure of tyres of the vehicle 200 being in a predefined pressure range, (iii) steering wheel angle being in a predefined steering wheel angle range, and (iv) speed of each wheel of the vehicle 200 being within a predefined range of speed of other wheels of the vehicle. The rationale behind consideration of each of the conditions is explained below:

[0030] The speed of the vehicle 200 is used as a criterion for deciding whether to detect misalignment because the speed has an impact on the hardness of the steering wheel 206, and consequently, the current drawn by the motor 208. Accordingly, if the speed of the vehicle 200 is less or more than a particular range, the steering current may not be used for detecting the misalignment. In an example, the predefined speed range is 20-50 kilometres per hour. The vehicle speed may be sensed by a speed sensor (not shown in Fig. 2) and may be received, for example, from another ECU, such as an antilock braking system (ABS) ECU 212 of the vehicle 200.
[0031] The pressures of tyres of the vehicle 200, such as the front left tyre 202 and the front right tyre 204, are used as criteria for deciding whether to detect misalignment because a tyre pressure less than a rated pressure of the tyre may cause a corresponding wheel to rotate faster. The faster rotation, in turn, may cause the motor 208 to draw more current. Therefore, if the tyre pressure is outside of a rated pressure range, such as 30-35 psi, the wheel misalignment may not be detected. In an example, the tyre pressure may be received from a Tyre Pressure Monitoring System (TPMS) ECU (not shown in Fig. 2) of the vehicle 200. The TPMS ECU may receive the pressure values from pressure sensors (not shown in Fig. 2) deployed in the vehicle 200.
[0032] The steering wheel angle is considered before detecting the misalignment because the steering wheel angle indicates whether the vehicle 200 is travelling in a substantially straight manner. If the vehicle 200 is not travelling straight (i.e., if the vehicle 200 is travelling in a curved path), the current drawn by the motor 208 may not be a reliable indicator of wheel misalignment. Accordingly, the wheel misalignment is detected if the vehicle 200 is travelling in a substantially straight manner. For instance, the wheel misalignment is detected if the steering wheel angle is in a range of 0-5°. The steering wheel angle is monitored by the EPAS ECU 210, which may employ a steering angle sensor for sensing the steering wheel angle.

[0033] The speed of each wheel relative to other wheels of the vehicle 200 is considered because a difference between the speed of one wheel from those of the other wheels may indicate the presence of a road camber. The wheel speeds may be received from the ABS ECU 212.
[0034] Upon satisfaction of the above conditions, the misalignment detection module 106 may infer that the current that would be drawn by the motor 208 may be a reliable indicator of a misalignment of a wheel. Subsequently, the misalignment detection module 106 may monitor the current drawn by the motor 208 for detecting wheel misalignment. In an implementation, the misalignment detection module 106 may determine the satisfaction of the above set of conditions for a predetermined time period before deciding to monitor the current drawn by the motor 208. The reason for monitoring the satisfaction of the set of conditions for a time period is to ensure that the satisfaction of conditions is not transitory. In an example, the predetermined time period is 30 seconds.
[0035] The misalignment detection module 106 may compare the current drawn by the motor 208 with a reference current value. The reference current value may be a current that would be drawn by the motor 208 when the various conditions explained above are satisfied and when the wheels are not misaligned. The comparison indicates whether there is a misalignment of any wheel of the vehicle 200. For example, if the current drawn by the motor 208 differs from the reference current value by more than a threshold value, the misalignment detection module 106 may infer that one or more wheels of the vehicle 200 are misaligned.
[0036] In an implementation, the misalignment detection module 106 monitor value of the current drawn by the motor 208 at a plurality of points of time in a particular time window. For example, the current values may be monitored at a 1-second interval for a period of 30 seconds. Accordingly, a plurality of samples of current drawn by the motor 208 are obtained. The misalignment detection module 106 may compute an average of the plurality of samples, such as a mean of the plurality of samples, and compare the average with the reference current value. The

misalignment detection module 106 may infer that a misalignment exists if the average differs from the reference current value by the threshold value. The inference based on the plurality of samples prevents false alarms. For example, an inference of wheel misalignment is not produced due to a transitory spike in the current drawn by the motor 208.
[0037] In an implementation, the misalignment detection module 106 may categorize each current sample obtained in a time window into a current range bin of a plurality of current range bins. Such a categorization results in the generation of a current bin plot, which indicates the number of current samples in each current range bin. The current bin plot may be compared against a reference current bin plot, and the misalignment may be detected based on the comparison. The current bin plot will be explained in greater detail with reference to Fig. 3.
[0038] Fig. 3 illustrates current bin plots that are usable for detecting misalignment of wheels of a vehicle, according to an implementation of the present subject matter. As explained above, samples of current drawn by the motor 208 in a particular time window may be periodically obtained. For example, current samples may be obtained once in a second for a period of 30 seconds. Further, each current sample obtained may be categorized into a current range bin. A current range bin may be a range of current values, such as -3 to -2 Ampere (A), -2 to -1 A, …, 2 to 3 A. The categorization of all the samples obtained may result in the generation of a current bin plot, which indicates the number of current samples in each current range bin. The current range plot obtained, in accordance with an example, is illustrated as a histogram with solid lines in Fig. 3. The current bin plot may be compared against a reference current bin plot, which is illustrated as a histogram with hatched lines. The reference current bin plot may be a current bin plot in a condition when no wheel of the vehicle 200 is misaligned. In Fig. 3, the reference current bin plot is shown slightly offset to the actual current bin plot to clearly differentiate between the two plots.

[0039] The comparison between the plots may involve comparing difference between the number of samples in a current range bin of the actual current bin plot and the number of samples in the corresponding current range bin of the reference current bin plot. For example, consider that the number of samples in the 1-2 A bin of the actual current bin plot is 5, and that the number of samples in the 1-2 A bin of the reference current bin plot is 8. Accordingly, the difference between the two is computed as 3. Similar differences are computed for the other bins, such as 0-1 A bin and 2-3 A bin.
[0040] Based on the differences computed for the various current range bins, the misalignment may be detected. For example, the differences computed for the various current range bins may be added and compared against a corresponding threshold. If the sum of differences exceeds the threshold value, it may be determined that one or more wheels are misaligned.
[0041] In an implementation, the comparison of the current range plots may be performed in addition to the comparison of the current values (i.e., comparison of the current drawn by the motor 208 with the reference current value). Further, the misalignment may be detected when both the comparisons return positive results (i.e., current value exceeds the reference current value by a threshold and sum of differences between the two current bin plots exceeds a corresponding threshold). The detection of the misalignment based on the two comparisons increases the accuracy of misalignment detection.
[0042] Upon detecting that one or more wheels are misaligned, the misalignment detection module 106 may provide an alert to a driver of the vehicle 200. The alert may be, for example, a visual alert, which may be provided on an instrument cluster 214 (shown in Fig. 2) of the vehicle 200. The alert may also be an audio alert, which may be provided through a loudspeaker (not shown in Fig. 2) of the vehicle 200.

[0043] Although the current bin plots are shown as histograms, in other implementations, the current bin plots may take other forms. For example, the current bin plots may be in the form of tables, arrays, or the like.
[0044] Fig. 4 illustrates a method 400 for detecting misalignment of wheels of a vehicle, according to an implementation of the present subject matter.
[0045] It may be understood that steps of the method 400 may be performed by programmed computing units. The steps of the method 400 may be executed based on instructions stored in a non-transitory computer readable medium, as will be readily understood. The non-transitory computer readable medium may include, for example, digital memories.
[0046] The order in which the method 400 is described is not intended to be construed as a limitation, and any number of the described method blocks can be combined in any order to implement the method 400, or an alternative method. Additionally, individual blocks may be deleted from the method 400 without departing from the scope of the subject matter described herein. Furthermore, the method 400 can be implemented in any suitable hardware, non-transitory machine-readable instructions, or combination thereof.
[0047] A person skilled in the art will readily recognize that steps of the method 400 can be performed by programmed computing devices. Herein, some examples are also intended to cover program storage devices, for example, digital data storage media, which are machine or computer-readable and encode machine-executable or computer-executable programs of instructions, wherein said instructions perform some or all of the steps of the described method. The program storage devices may be, for example, digital memories, such as the memory 104 (not shown in Fig. 3).
[0048] In an implementation, the method 400 may be implemented in the vehicle 200 (not shown in Fig. 4), for example, by the misalignment detection module 106.

In the below explanation, the method 400 is explained with reference to the vehicle 200. However, the method 400 may be implemented in a variety of vehicles.
[0049] The method beings at block 402. At blocks 404-410, it is determined if the conditions under which wheel misalignment can be detected are satisfied. For instance, at block 404, it is determined if vehicle speed is in a predetermined range, such as 20-50 km/hr. If yes, at block 406, it is checked if the tyres of the vehicle 200 have pressure within a predefined pressure range. If yes, at block 408, it is determined if the steering wheel 206 is substantially straight. For example, it is determined the steering wheel angle is in a predefined steering wheel angle range, such as 0-5 degrees. If yes, at block 410, it is determined if speed of a wheel of the vehicle is within a predefined range of speeds of other wheels of the vehicle 200. For example, it may be checked if speed of one wheel is within +/- 2 percent of speeds of other wheels.
[0050] If the result of any condition checked at blocks 404-410 is negative, it is determined that wheel misalignment cannot be detected based on the current drawn by the motor 208. Accordingly, the method returns to block 402. If the result of all the conditions checked at blocks 404-410 are true, it is inferred that the current drawn by the motor 208 is a reliable indicator of wheel misalignment. In an example, the inference is made if the conditions are satisfied for a predetermined period, such as 30 seconds.
[0051] Upon satisfaction of the conditions examined at blocks 404-410, at block 412, current drawn by the steering motor 208 is monitored for a time window, such as 30 seconds. Further, at block 414, the current drawn is compared with a reference current value. In an implementation, a plurality of samples of current obtained in the time window are averaged, and the average value may be compared with the reference current value. If it is determined that a difference between the steering motor current and the reference current value is more than a threshold, at block 416, an actual current bin plot, such as the histogram in solid lines in Fig. 3, may be compared with a reference current bin plot, such as the histogram in hatched lines

in Fig. 3. The comparison may be performed in the manner explained with reference to Fig. 3. If the difference between the actual current bin plot and the reference current bin plot is greater than a threshold, it may be detected that one or more wheels are misaligned. Accordingly, at block 418, a warning, such as an audio or a video warning, may be outputted.
[0052] Fig. 5 illustrates various current bin plots for misaligned wheels and for aligned wheels obtained based on various trials, according to an implementation of the present subject matter. The current bin plots are plotted after ensuring that the current drawn by a steering wheel motor is a reliable indicator of misalignment of wheels of a vehicle. For example, the plots are made after satisfaction of the conditions explained in method blocks 404-410. Here, the X-axis indicates the values of current drawn by the steering wheel motor and the Y-axis indicates the period of time for which a particular current value is observed. The difference between the current bin plots of misaligned configuration of wheels and those of aligned configuration of wheels is clearly discernible, as indicated by the offsets 502, 504, and 506. The above plots prove that steering motor current is a reliable indicator of misalignment of one or more wheels of a vehicle.
[0053] The present subject matter provides a simple, effective, and accurate manner of detecting wheel misalignment in a vehicle. The present subject matter can be implemented using sensors and components that are typically provided in a vehicle. Further, the present subject matter uses simple computations for detecting the misalignment.
[0054] The foregoing description of the specific implementations will so fully reveal the general nature of the implementations herein that others can, by applying current knowledge, readily modify and/or adapt for various applications without departing from the generic concept, and, therefore, such modifications and adaptations should and are intended to be comprehended within the meaning and range of equivalents of the disclosed implementations. 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 implementations herein have been described in terms of preferred implementations, those skilled in the art will recognize that the implementations herein can be practiced with modification within the spirit and scope of the implementations as described herein.

We Claim:
1. A device for detecting misalignment of a wheel of a vehicle, the vehicle
comprising a steering wheel to control movement of the wheel and a motor
corresponding to the steering wheel, the device comprising:
a processor; and
a misalignment detection module executable by the processor to: compare current drawn by the motor corresponding to the steering wheel with a reference current value; and
detect misalignment based on the comparison.
2. The device as claimed in claim 1, wherein, prior to comparing current drawn
by the motor with the reference current value, the misalignment detection module
is executable to:
determine if conditions under which wheel misalignment is detectable are satisfied; and
perform the comparison in response to satisfaction of the conditions.
3. The device as claimed in claim 2, wherein, to determine if conditions under
which wheel misalignment is detectable are satisfied, the misalignment detection
module is executable to:
determine if speed of the vehicle is in a predefined speed range;
determine if pressure of tyres of the vehicle are in a predefined pressure range;
determine if steering wheel angle is in a predefined steering wheel angle range;
determine if speed of each wheel of the vehicle is within a predefined range of speed of other wheels of the vehicle.
4. The device as claimed in claim 1, wherein, to compare the current drawn by
the motor with the reference current value, the misalignment detection module is
executable to:

monitor a plurality of samples of the current drawn by the motor in a time window;
compute an average current value of the plurality of samples; and compare the average current value with the reference current value.
5. The device as claimed in claim 1, wherein, to detect the misalignment, the
misalignment detection module is further to:
obtain a plurality of samples of the current drawn by the motor in a time window;
categorize each sample into a current range bin of a plurality of current range bins, the categorization of the plurality of samples resulting in generation of a current bin plot, wherein the current bin plot indicates the number of samples in each current range bin of the plurality of current range bins;
compare the current bin plot with a reference current bin plot; and
detect misalignment based on the comparison of the current bin plot with the reference current bin plot.
6. The device as claimed in claim 1, wherein, in response to detection of the
misalignment, the misalignment detection module is executable to provide an alert
to a driver of the vehicle.
7. A vehicle comprising:
a plurality of wheels;
a steering wheel usable to control movement of the plurality of wheels;
a steering wheel motor to aid in movement of the plurality of wheels based on rotation of the steering wheel;
a processor; and
a misalignment detection module executable by the processor to:
compare current drawn by the steering wheel motor with a reference current value; and
detect misalignment of a wheel of the plurality of wheels based on the comparison.

8. The vehicle as claimed in claim 7, wherein, prior to comparing current drawn
by the steering wheel motor with the reference current value, the misalignment
detection module is executable to:
determine if conditions under which misalignment of a wheel of the plurality of wheels is detectable are satisfied; and
perform the comparison in response to satisfaction of the conditions.
9. The vehicle as claimed in claim 8, comprising:
a speed sensor to sense speed of the vehicle and speeds of wheels of the vehicle;
a plurality of pressure sensors to determine pressure in a plurality of tyres of the vehicle; and
a steering angle sensor to determine angle of rotation of the steering wheel, wherein, to determine if conditions under which wheel misalignment is detectable are satisfied, the misalignment detection module is executable to:
determine if the speed of the vehicle is in a predefined speed range;
determine if the pressure of the plurality of tyres of the vehicle are in a predefined pressure range;
determine if the angle of rotation of the steering wheel is in a predefined steering wheel angle range; and
determine if speed of each wheel of the vehicle is within a predefined range of speed of other wheels of the vehicle.
10. The vehicle as claimed in claim 5, wherein the processor is part of an electronic control unit (ECU) that is to control the steering wheel motor.
11. A method for detecting misalignment of a wheel of a vehicle, the vehicle comprising a steering wheel to control movement of the wheel and a motor corresponding to the steering wheel, the method comprising:
comparing current drawn by a motor corresponding to a steering wheel of the vehicle with a reference current value; and
detecting misalignment based on the comparison.

12. The method as claimed in claim 11, wherein, prior to comparing current
drawn by the motor with the reference current value, the method comprises:
determining if conditions under which wheel misalignment is detectable are satisfied; and
determining that the comparison is to be performed in response to satisfaction of the conditions.
13. The method as claimed in claim 12, determining if conditions under which
wheel misalignment is detectable are satisfied comprises:
determining if speed of the vehicle is in a predefined speed range;
determining if pressure of tyres of the vehicle are in a predefined pressure range;
determining if steering wheel angle is in a predefined steering wheel angle range; and
determining if speed of each wheel of the vehicle is within a predefined range of speed of other wheels of the vehicle.
14. The method as claimed in claim 11, wherein comparing the current drawn by
the motor with the reference current value comprises:
obtaining a plurality of samples of the current drawn by the motor in a time window;
computing an average current value of the plurality of samples; and comparing the average current value with the reference current value.
15. The method as claimed in claim 11, comprising:
obtaining a plurality of samples of the current drawn by the motor in a time window;
categorizing each sample into a current range bin of a plurality of current range bins, the categorization of the plurality of samples resulting in generation of a current bin plot, wherein the current bin plot indicates the number of samples in each current range bin of the plurality of current range bins;
comparing the current bin plot with a reference current bin plot; and

detecting misalignment based on the comparison of the current bin plot with the reference current bin plot.