Description:TECHNICAL FIELD
This disclosure generally relates to a brake system in a vehicle, and more particularly to a method and device for detecting and monitoring air leakage in real time in pneumatic braking systems in the vehicle.
BACKGROUND
The braking system of vehicles, incorporating pneumatic tubing & connectors, and foundation brake assembly, stands as a critical component for ensuring both safety and operational efficiency. Wear-related issues, ruptured pipes, misfit connectors, and deteriorating seals within the system, create safety hazards and render brake system ineffective. Undetected leaks in the pneumatic brake system not only compromise the effectiveness of braking but also result in a discernible reduction in the overall efficiency of the braking system. The compromised efficiency of the braking system translates into potential risks for the vehicle. This includes diminished braking performance, extended stopping distances, and an elevated likelihood of accidents due to inadequate responsiveness.
Therefore, it is imperative to take a pre-emptive action based on the onset of failure to avoid accidents as a result of a failure of the pneumatic braking system. Thus, there is a requirement for effective leakage detection and monitoring in real time in pneumatic brake systems.
SUMMARY OF THE INVENTION
In an embodiment, a method for detecting and monitoring air leakage in a pneumatic brake system in a vehicle is disclosed. The method may include, determining, by an air leakage detection device, a first differential pressure rate value of a front brake circuit, a second differential pressure rate value of a rear brake circuit and a third differential pressure rate value of a parking brake circuit, microcontroller and air pressure sensors. In an embodiment, the first differential pressure rate value, the second differential pressure rate value and the third differential pressure rate value may be determined based on a change in pressure in a first predefined time period in pneumatic lines of the front brake circuit, the rear brake circuit, and the parking brake circuit respectively. The method may include determining a sum of the first differential pressure rate value, the second differential pressure rate value and the third differential pressure rate value by the air leakage detection device. The method may further include determining a state of brake pedal and a state of the hand brake lever by the air leakage detection device. The method may further include determining an ignition state of the vehicle by the air leakage detection device. Upon determining the ignition state of the vehicle as ON, the state of the brake pedal as unpressed, and the state of the hand brake lever as unpressed, the air leakage detection device may determine a leakage in the pneumatic brake system in case the sum is determined greater than a leakage threshold value. Further, the method may include, displaying, by the air leakage detection device, an alert on an output device of the vehicle based on the determination of the leakage in the pneumatic brake system.
In another embodiment, an air leakage detection device in a vehicle is disclosed. The device may include a processor and a memory coupled to the processor. In an embodiment, the memory stores a first set of instructions, which, on execution, causes the processor to determine a first differential pressure rate value of a front brake circuit, a second differential pressure rate value of a rear brake circuit and a third differential pressure rate value of a parking brake circuit. In an embodiment, the first differential pressure rate value, the second differential pressure rate value and the third differential pressure rate value are determine based on a change in pressure in a first predefined time period in pneumatic lines of the front brake circuit, the rear brake circuit, and the parking brake circuit respectively. The processor may determine a sum of the first differential pressure rate value, the second differential pressure rate value and the third differential pressure rate value. The processor may further determine a state of brake pedal and a state of hand brake lever. The processor may further determine an ignition state of the vehicle. The processor after determination of the state of brake pedal as unpressed, the state of hand brake as disengaged and the ignition state as ON, may further determine a leakage in the pneumatic brake system in case the sum is determined to be greater than a leakage threshold value and display an alert on an output device of the vehicle based on the determination of the leakage in the pneumatic brake system.
BRIEF DESCRIPTION OF DRAWINGS
The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate exemplary embodiments and, together with the description, serve to explain the disclosed principles.
FIG. 1 illustrates a block diagram of an air leakage detection system in a pneumatic brake system in a vehicle, in accordance with an embodiment of the present disclosure;
FIG. 2 illustrates a functional module diagram of air leakage detection device of FIG. 1, in accordance with an embodiment of the present disclosure;
FIG. 3 illustrates a flowchart of a method of detecting air leakage in pneumatic brake system when the ignition of the vehicle is ON, in accordance with an embodiment of the present disclosure;
FIG. 4 illustrates a flowchart of a method of detecting air leakage in air leakage in the front brake circuit, the rear brake circuit, and/or the parking brake circuit when the ignition of the vehicle is ON, in accordance with an embodiment of the present disclosure;
FIG. 5 illustrates a flowchart of a method of detecting air leakage in the front brake circuit, the rear brake circuit, and/or the parking brake circuit when the ignition of the vehicle is OFF, in accordance with an embodiment of the present disclosure; and
DETAILED DESCRIPTION OF THE DRAWINGS
The foregoing description has broadly outlined the features and technical advantages of the present disclosure in order that the detailed description of the disclosure that follows may be better understood. Additional features and advantages of the disclosure will be described hereinafter which forms the subject of the claims of the disclosure. It should be appreciated by those skilled in the art that the conception and specific embodiments disclosed may be readily utilized as a basis for modifying other devices, systems, assemblies, and mechanisms for carrying out the same purposes of the present disclosure. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the scope of the disclosure as set forth in the appended claims. The novel features which are believed to be characteristics of the disclosure, to its device or system, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present disclosure.
The terms “including”, “comprises”, “comprising”, “comprising of” or any other variations thereof, are intended to cover a non-exclusive inclusions, such that a system or a device that comprises a list of components or steps does not include only those components or steps but may include other components or steps 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.
Reference will now be made to the exemplary embodiments of the disclosure, as illustrated in the accompanying drawings. Wherever possible, same numerals have been used to refer to the same or like parts. The following paragraphs describe the present disclosure with reference to FIGs. 1 - 5. It is to be noted that the system may be employed in any vehicle having pneumatic braking system, including but not limited to a passenger vehicle, a utility vehicle, commercial vehicles, and any other transportable machinery.
As mentioned before, vehicle braking systems necessitates constant inspection to detect ruptured pipes, ill-fitted connectors, and worn-out seals, or any similar anomaly that may increase a likelihood of substantial air leakage, thereby resulting in brake failure. Conducting comprehensive inspections, especially for air leaks, proves time-intensive, presenting challenges in preserving peak system performance over a lifecycle of the vehicle.
To this end, an air leakage detection device is disclosed. The air leakage detection device may be implemented in an air leakage detection system, which may be configured to monitor and detect leakage in at least one pneumatic circuit of the vehicle braking systems. Now referring to FIG. 1 which illustrates a block diagram 100 of an air leakage detection system 102, in accordance with an embodiment of the present disclosure. The air leakage detection system 102 may be configured to detect an air leakage in a pneumatic brake system 114.
In an embodiment, with continued reference to FIG. 1, the air leakage detection system 102 may include an air leakage detection device 104, an Electronic Control Unit (hereinafter referred to as ECU) 110, one or more pressure sensors 112 and the pneumatic braking system 114. In an embodiment, the air leakage detection device 104 may be communicably connected to the one or more pressure sensors 112. Further, the one or more pressure sensors 112 may be communicably connected to the pneumatic braking system 114. Further, the processor 106 may be connected to the ECU 110. The communication between the components of the air leakage detection system may include a wireless or a wired connection, or a combination of both. In an embodiment, the wired connection may be implemented by hard-wiring each of the components of the air leakage detection system 102, and the wireless network or a combination thereof can be implemented as one of the different types of networks, via vehicle communication bus, operating on wireless protocols, including, but not limited to A²B (Automotive Audio Bus), AFDX, ARINC 429, Byteflight, CAN (Controller Area Network) , D2B – (Domestic Digital Bus), FlexRay, IDB-1394, IEBus, I²C, ISO 9141-1/-2, J1708 and J1587, J1850, J1939 and ISO 11783 – an adaptation of CAN for commercial (J1939) and agricultural (ISO 11783) vehicles, Keyword Protocol 2000 (KWP2000), LIN (Local Interconnect Network), MOST (Media Oriented Systems Transport), IEC 61375, SMARTwireX, SPI, and/or VAN – (Vehicle Area Network), and the like.
In an embodiment, the pneumatic braking system 114 may include a front brake circuit 116, a rear brake circuit 118 and a parking brake circuit 120. The front brake circuit 116, the rear brake circuit 118, and the parking brake circuit 120 may be implemented as pneumatic brake circuits formed by interconnected conduits, valves, and actuators, and the like. Further, the front brake circuit 116, the rear brake circuit 118, and the parking brake circuit 120 function to convert mechanical input into pneumatic pressure which may be utilized to actuate brakes in the vehicle braking systems. In an embodiment, the front brake circuit 116 may be configured to provide an effective braking on a vehicle's front axle. Similarly, the rear brake circuit 118 is structured with a distinct air pressure, to fulfill braking needs of a rear axle and to ensure balanced braking distribution with proper synchronization to the braking of the front brake circuit 116. Additionally, the parking brake circuit 120 utilizes a separate air pressure, precisely adjusted to activate a parking brake mechanism. As may be appreciated, the front brake circuit 116 and the rear brake circuit 118 may be actuated by the driver by actuating a brake pedal (not shown). Further, the parking brake circuit 120 may be actuated by the driver by engaging the parking brake lever (not shown).
In an embodiment, with continued reference to FIG. 1, the air leakage detection device 104 may include one or more processors 106 (hereinafter referred to as processor 106). Alternatively, the functions of the air leakage detection device 104 may be implemented using the ECU 110. The processor 106, and the ECU may be implemented as one or more microprocessors, microcomputers, single board computers, microcontrollers, digital signal processors, central processing units, graphics processing units, logic circuitries, and/or any devices that manipulate data received from a memory 108. Among other capabilities, the one or more processor(s) 106 are configured to fetch and execute computer-readable instructions stored in a memory 108 of the air leakage detection device 104 to determine leakage occurring in the pneumatic brake system 114 of the vehicle. The memory 108 may store one or more computer-readable instructions or routines, which may be fetched and executed to create or share the data over a network service. The memory 108 may be a non-volatile memory or a volatile memory. Examples of non-volatile memory may include, but are not limited to a flash memory, a Read Only Memory (ROM), a Programmable ROM (PROM), Erasable PROM (EPROM), and Electrically EPROM (EEPROM) memory. Examples of volatile memory may include but are not limited to Dynamic Random Access Memory (DRAM), and Static Random-Access Memory (SRAM). The memory 108 may also store various vehicle information such as design manuals, operational parameters, emergency parameters, etc. that may be captured, processed, and/or required by the air leakage detection system 102.
In an embodiment, as explained earlier, the air leakage detection device 104 may be connected to the one or more pressure sensors 110. In an embodiment, the one or more pressure sensors 110 may include, but not be limited to, high-resolution pressure sensors such as strain gauge pressure sensors, piezoelectric pressure sensors, capacitive pressure sensors, resonant wire pressure sensors, and the like. Further, the one or more pressure sensors 110 may be connected to the front brake circuit 116, the rear brake circuit 118, and the parking brake circuit 120. In an embodiment, the one or more pressure sensors 110 may be configured to sense instantaneous air pressure values across the pneumatic circuitry of front brake circuit 116, the rear brake circuit 118, and the parking brake circuit 120 respectively. Further, the one or more sensors 110 may be configured to transmit the instantaneous air pressure values to the air leakage detection device 104.
In an embodiment, the air leakage detection device 104 after receiving the instantaneous air pressure values, may be configured to determine differential pressure rate values across the front brake circuit 116, the rear brake circuit 118, and the parking brake circuit 120 over a first predefined time period. In an embodiment, the first predefined time period may be equal to 150 seconds based on experimental data. Particularly, the air leakage detection device 104 may be configured to determine a first differential pressure rate value across the front brake circuit 116, a second differential pressure rate value across the rear brake circuit 118, and a third differential pressure rate value across the parking brake circuit 120. In an embodiment, the first differential pressure rate value, the second differential pressure rate value, and the third differential pressure rate value may be determined based on a change in pressure across the front brake circuit 116, the rear brake circuit 118, and the parking brake circuit 120 respectively. Further, the change in air pressure values across the front brake circuit 116, the rear brake circuit 118, and the parking brake circuit 120 may be determined by one or more sensors 110 over the first predefined time period. In an embodiment, air leakage detection device 104 may be configured to determine an air leakage when the first differential pressure rate value, the second differential pressure rate value, and the third differential pressure rate value, individually or a sum of each of the values may exceed a leakage threshold value. In an embodiment, the leakage threshold value may be predefined and may be determined based on experimental data.
In an embodiment, air leakage detection device 104 may be configured to determine a sum of the first differential pressure rate value, the second differential pressure rate value, and the third differential pressure rate value. Further, air leakage detection device 104 may also be configured to determine a state of the brake pedal and a state of the hand brake lever. For example, the air leakage detection device 104 may be configured to determine if the brake pedal is pressed on unpressed and/or the hand brake lever may be engaged or disengaged. In an embodiment, the air leakage detection device 104 may determine a state of the brake pedal and a state of the hand brake lever and/or an ignition state of the vehicle from the ECU 110. In an embodiment, when the state of the brake pedal is unpressed or disengaged, the state of the hand brake lever is unpressed or is disengaged and the ignition state is ON, the air leakage detection device 104 may be configured to determine leakage in the pneumatic brake system in case the sum is greater than the leakage threshold value. Further, the air leakage detection device 104 may be configured to generate and transmit an alert to an output device of the vehicle based on the determination of the leakage.
In an embodiment, now referring to FIG. 2 which illustrates a functional block diagram 200 of the air leakage detection device 104 of FIG. 1, in accordance with an embodiment of the present disclosure. The air leakage detection device 104 may include a sensor module 202, a pneumatic brake pressure module 204, a leakage determination module 214, and an alert module 216.
In an embodiment, the sensor module 202 may be configured to receive the instantaneous air pressure values across the front brake circuit 116, the rear brake circuit 118, and the parking brake circuit 120 as sensed by one or more pressure sensors 110 at various time instants. The instantaneous air pressure values may correspond to real-time pressure values as determined by the one or more pressure sensors 110 in the pneumatic circuits of each of the front brake circuit 116, the rear brake circuit 118, and the parking brake circuit 120. In an embodiment, the sensor module 202, in addition to the instantaneous air pressure values, may also receive sensor outputs from various sensors in the vehicle. For example, sensor outputs such as but not limited to the status (ON/OFF) of vehicle ignition, speed of the engine sensed by the odometer, a state of brake pedal, and/or a state of hand brake lever and the like may be determined by the sensor module 202.
In an embodiment, the pneumatic brake pressure module 204 may be implemented by the processor 106 executing a set of instructions stored in the memory 108 of the air leakage detection device 104. The pneumatic brake pressure module 204 may be configured to obtain the instantaneous air pressure values across the front brake circuit 116, the rear brake circuit 118, and the parking brake circuit 120 from the sensor module 202. In an embodiment, the pneumatic brake pressure module 204 may include a front brake pressure module 206, a rear brake pressure module 208, and a parking brake pressure module 210. The pneumatic brake pressure module 204 may determine a differential pressure rate value in pneumatic lines of the pneumatic brake system 114. For example, the front brake pressure module 206 may determine the first differential pressure rate value in the pneumatic line of the front brake circuit 116. Further, the rear brake pressure module 208 may determine the second differential pressure rate value in the pneumatic line of the rear brake circuit 118. The parking brake pressure module 210 may determine the third differential pressure rate value in the pneumatic line of the parking brake circuit 120.
In an embodiment, as explained earlier, the first differential pressure rate value may be determined by the front brake pressure module 206. In an embodiment, the first differential pressure rate value may be defined as a change in instantaneous air pressure values in the front brake circuit 116 over a first predefined time period. In an embodiment, the first differential pressure rate value may be determined based on the equation (1.1) given below:
?Pf=Pf1-Pf2t2-t1 … (1.1)
Where:
(?P)f = First differential pressure rate value in the front brake circuit 116;
Pf1 = Instantaneous air pressure value in the front brake circuit 116 at time t1; and
Pf2 = Instantaneous air pressure value in the front brake circuit 116 at time t2.

Further, as explained earlier, the second differential pressure rate value may be determined by the rear brake pressure module 208. In an embodiment, the second differential pressure rate value rate may be defined by a change in instantaneous air pressure values over a first predefined time period in the rear brake circuit 118. The second differential pressure rate value rate may be determined by the equation (1.2) given below:
?Pr=Pr1-Pr2t2-t1 … (1.2)
Where:
(?P)r = Second differential pressure rate value in the rear brake circuit 118;
Pr1 = Instantaneous air pressure value in the rear brake circuit 118 at time t1; and
Pr2 = Instantaneous air pressure value in the rear brake circuit 118 at time t2.
Finally, the third differential pressure rate value may be determined by the parking brake pressure module 210. In an embodiment, the third differential pressure rate value rate may be defined as a change in instantaneous air pressure values over a first predefined time period in the parking brake circuit 120. The parking brake differential pressure value rate may be determined by the equation (1.3) given below:
?Pp=Pp1-Pp2t2-t1 … (1.3)
Where:
(?P)p = Third differential pressure rate value in the parking brake circuit 120;
Pp1 = Instantaneous air pressure value in the parking brake circuit 120 at time t1; and
Pp2 = Instantaneous air pressure value in the parking brake circuit 120 at time t2.
In an embodiment, the leakage determination module 214 may be implemented by the processor 106 executing another set of instructions stored in the memory 108 of the air leakage detection device 104. The leakage determination module 214 may be configured to detect air leakage occurring in pneumatic lines in the front brake circuit 116, the second brake circuit 118, and/or the parking brake circuit 120. In an embodiment, the leakage determination module may be configured to receive the first differential pressure rate value (?P)f, the second differential pressure rate value (?P)r, and the third differential pressure rate value (?P)p from the pneumatic brake pressure module 204. In an embodiment, the leakage may be determined when the first differential pressure rate value, the second differential pressure rate value, and the third differential pressure rate value individually or cumulatively exceed a leakage threshold value. In an embodiment, the leakage threshold value may be set based on experimental data. It must be noted that at least one of the first differential pressure rate value (?P)f, the second differential pressure rate value (?P)r, and the third differential pressure rate value (?P)p exceeds the leakage threshold may indicate a leak in the front brake circuit 116, the second brake circuit 118, and the parking brake circuit 120 respectively.
However, in some scenarios, it is observed that individually the first differential rate value, the second differential rate value, and the third differential rate value may not exceed the leakage threshold. In such scenarios, air leaked collectively therefrom may result in a reduction of air in their respective pneumatic circuit lines, thereby reducing the braking efficiency of the pneumatic brake system 114.
In such scenarios, the leakage determination module 214 may be configured to determine a collective leakage occurring from the pneumatic braking system 114. The collective leakage may be determined by the leakage determination module 214, by calculating a sum of the first differential rate value (?P)f, the second differential rate value (?P)r, and the third differential rate value (?P)p. If the sum exceeds the leakage threshold, a collective leakage in the pneumatic braking system 114 may be determined by the leakage determination module 214.
As explained earlier, the instantaneous air pressure values may be determined by the one or more pressure sensors 110. The one or more pressure sensors 110, being high-resolution pressure sensors may determine instantaneous air pressure values in all conditions, even when there exists no leakage in the pneumatic braking system 114. For example, during normal operation of the vehicle, actuating the brake pedal may result in increase or decrease of air pressure in the pneumatic lines due to air being displaced or exhausted. Accordingly, displacement or exhaustion of air may increase or decrease the air pressure in the pneumatic lines which may be sensed by the one or more pressure sensors 110. As a result, the differential pressure rate values determined based on set of instantaneous air pressure values sensed by the one or more pressure sensors 110 during the actuation of the brake pedal may result in determination of false leakage. Consequently, the leakage determination module 214 may be configured to ignore such differential pressure rate values determined during the actuation of the brake pedal. This process may lead to inadvertent determination of a leakage by the leakage determination module 214.
Therefore, to rule out the possibility of detection of a false leakage, the leakage determination module 214 may be configured to check the state of engagement of the brake pedal. In addition, the leakage determination module 214, may be configured to check whether the hand brake lever (also referred to herein as parking brake lever) is engaged for a predefined waiting time period (interchangeably referred to as pause period). In an embodiment, the pause period may be determined based on experimental data. In an embodiment, when the hand brake lever may be engaged for a time period exceeding the pause period, it may be deduced that the hand brake lever is permanently engaged, and the vehicle is in a stationary state. Therefore, the leakage determined by the leakage determination module 214 when the hand brake lever may be engaged for a time period less than the pause period may be rendered as false leakage determination. Therefore, a leakage is detected in the parking brake circuit only when the hand brake lever may be engaged for a time period greater than the pause period.
In an embodiment, with continued reference to FIG. 2, the alert module 216 may be configured to generate a visual and/or audio alert in case a leakage is detected from the front brake circuit 116, the rear brake circuit 118, and/or the parking brake circuit 120, or collectively in the pneumatic brake system 114. Accordingly, a warning notification may be displayed on an infotainment device/instrument cluster device (not shown) of the vehicle.
As explained before, the air leakage detection device 104, using the leakage determination module 214 may be configured to determine the leakage occurring in the pneumatic brake system 114. Particularly, the leakage determination module 214 may be configured to detect leakage occurring in the pneumatic brake system 114 in all operational conditions of the vehicle. In an embodiment, the operational conditions may include determining the state of ignition of the engine (when the engine is ON or OFF). Particularly, the operational conditions may include a first condition in which the engine is in operation and the state of ignition is ON, and the vehicle is in a state of motion. Additionally, the operational conditions may include a second condition in which the state of ignition is ON, and the vehicle is in a stationary state. Furthermore, the operational conditions may include a third condition in which the engine is turned OFF while the vehicle remains in a stationary state. In an embodiment, the state of motion, and the stationary state, along with the state of ignition may be determined by the sensor module 202. In particular, the sensor module 202 may acquire status on whether the vehicle is moving or stationary, along with whether the engine is running, or the state of ignition is ON. This status may be obtained by the ECU 110 through one or more sensors installed in the vehicle designated to detect these states.
Now, referring to FIG. 3, which illustrates a flowchart 300 of a method of detecting air leakage of the pneumatic brake system 114, in accordance with an embodiment of the present disclosure.
At step 302, the first differential pressure rate value (?P)f may be determined by the front brake pressure module 206. Further, at step 304, the second differential pressure rate value (?P)r may be determined by the rear brake pressure module 208. Further, at step 306, the third differential pressure rate value (?P)p may be determined by the parking brake sensor module 210.
After determining the first differential pressure rate value (?P)f, the second differential pressure rate value (?P)r, and the third differential pressure rate value (?P)p, the method may proceed to the next step 308 in which a sum of the first differential pressure rate value (?P)f, the second differential pressure rate value (?P)r and the third differential pressure rate value (?P)p may be determined by the leakage detection module 214. Further, in the same step, the leakage detection module 214 may be configured to determine whether the sum exceeds the leakage threshold (Pth).
If the sum exceeds the leakage threshold (Pth) at step 308, the leakage detection module 214 may determine if at step 309 if the ignition state of the vehicle is ON. In case, at step 309, the ignition state of the vehicle is determined to be ON, the leakage detection module 214 at step 310 may determine if the state of the brake pedal is unpressed and if the state of the hand brake lever is unpressed. In case at step 310, it is determined that the state of the brake pedal is unpressed, the state of the hand brake lever is unpressed, then leakage detection module 214 may determine a leakage in the pneumatic brake system 114 at step 314. Further, at step 316, the alert module 216 may display an alert on a display of the vehicle depicting that a leakage may be present in the pneumatic brake system 114 of the vehicle. Further, in case the sum is below the leakage threshold (Pth) at step 308, then no leakage may be determined at step 312. Further, in case if the state of the brake pedal is determined to be pressed or if the state of the hand brake lever is determined to be pressed at step 310 then no leakage may be determined at step 312.
Now, FIG. 4 illustrates a flowchart 400 of a method of detecting air leakage in the front brake circuit 116, the rear brake circuit 118, and/or the parking brake circuit 120, in accordance with an embodiment of the present disclosure.
At step 402, the first differential pressure rate value (?P)f may be determined by the front brake pressure module 206. Further, at step 404, the second differential pressure rate value (?P)r may be determined by the rear brake pressure module 208. Further, at step 406, the third differential pressure rate value (?P)p may be determined by the parking brake sensor module 210.
At step 408, the leakage determination module 214 may determine whether the first differential pressure rate value (?P)f exceeds the leakage threshold value (Pth). Further, at step 410, the leakage determination module 214 may determine whether the second differential pressure rate value (?P)r exceeds the leakage threshold value (Pth). At step 412, the leakage determination module 214 may determine whether the second differential pressure rate value (?P)r exceeds the leakage threshold value (Pth).
In an embodiment, if at step 408 the first differential pressure rate value (?P)f, exceeds the leakage threshold value (Pth) then method may proceed to step 414. Further, if at step 410 the second differential pressure rate value (?P)r exceeds the leakage threshold value (Pth), the method may proceed to step 414. Further, if at step 412, the third differential pressure rate value (?P)p exceeds the leakage threshold value (Pth), the method may proceed to the step 414.
At step 414, the leakage determination module 214 may determine if the ignition state of the vehicle is ON or OFF. In case the ignition state of the vehicle is determined as ON at step 414, the method may proceed to step 416. At step 416, the leakage detection module 214 may be configured to inspect whether the state of the brake pedal is unpressed or engaged. If the brake pedal is determined to be engaged at step 416, the leakage detection module 214 may determine no leakage at step 420.
Further, in case the brake pedal is determined to be unpressed at step 416, the leakage detection module 214 may then determine the state of hand lever at step 418. Further, in case the state of hand lever is determined to be unpressed at step 418, the leakage detection module 214 may determine leakage in the front brake circuit 116 at step 422 in case the first differential pressure rate value (?P)f, exceeds the leakage threshold value (Pth) at step 408. Further, the leakage detection module 214 may determine leakage in the rear brake circuit 118 at step 422 in case the second differential pressure rate value (?P)r exceeds the leakage threshold value (Pth) at step 410 and the brake pedal is determined to be unpressed at step 416 and the hand lever is determined to be unpressed at step 418. Further, in case the state of hand lever is determined to be engaged at step 418, the leakage detection module 214 may determine no leakage be determined at step 420.
Further, in case the third differential pressure rate value (?P)p exceeds the leakage threshold value (Pth) at step 412 and the brake pedal is determined to be unpressed at step 416 and the hand lever is determined to be engaged or pressed at step 418, the method may proceed to step 421. At step 421, the leakage detection module 214 may determine if the hand brake lever has been engaged for a time period greater than the predefined pause period. In an embodiment, the predefined pause period may be equal to or greater than 5 sec. In case, at step 421 it is determined that the hand brake lever has been engaged for a time period greater than the predefined pause period, the leakage detection module 214 may determine leakage in the parking brake circuit 120 at step 422. Further, in case, at step 421 it is determined that the hand brake lever has been engaged for a time period less than the predefined pause period, the leakage detection module 214 may determine no leakage be determined at step 420.
Further, at step 424, the alert module 216 may display an alert on a display of the vehicle depicting that a leakage may be present in the front brake circuit 116, the rear brake circuit 118, or the parking brake circuit 120 of the vehicle in case of determination of a leakage at step 422.
Now, referring to FIG. 5 which illustrates a flowchart 500 of a method of detecting air leakage in the front brake circuit, the rear brake circuit, and/or the parking brake circuit when the ignition of the vehicle is OFF, in accordance with an embodiment of the present disclosure.
When the ignition of the vehicle is determined to be OFF at step 309 of flowchart 300 and at step 414 of flowchart 400, steps of the flowchart 500 may be performed.
At step 502, the first differential pressure rate value (?P)f may be determined by the front brake pressure module 206. Further, at step 504, the second differential pressure rate value (?P)r may be determined by the rear brake pressure module 208. Further, at step 506, the third differential pressure rate value (?P)p may be determined by the parking brake sensor module 510. Further, at step 503, a sum of the first differential pressure rate value (?P)f, the second differential pressure rate value (?P)r, and the third differential pressure rate value (?P)p may be determined. It is to be noted that the first differential pressure rate value, the second differential pressure rate value, the third differential pressure rate value may be determined based on instantaneous pressure values determined for a fourth predefined time period after the ignition of the vehicle has been turned OFF. Further, the fourth predefined time period may be equal to, but not limited to, 15 minutes.
If the sum exceeds the leakage threshold (Pth) at step 503, the leakage detection module 214 may determine if the state of the brake pedal is unpressed at step 516. Further, in case the brake pedal is determined as unpressed at step 516, the leakage detection module 214 may determine and if the state of the hand brake lever is disengaged or engaged at step 518. In case at step 518, it is determined that the state of the hand brake lever is disengaged, then leakage detection module 214 may determine a leakage in the pneumatic brake system 114 at step 522. Further, at step 524, the alert module 216 may display an alert on a display of the vehicle depicting that a leakage may be present in the pneumatic brake system 114 of the vehicle. Further, in case the sum is below the leakage threshold (Pth) at step 503, then no leakage may be determined at step 520. Further, in case the sum is above the leakage threshold (Pth) at step 503 and the state of brake pedal is determined as pressed at step 516 then no leakage may be determined at step 520. Further, in case the state of brake pedal is determined as unpressed at step 516 and the state of hand brake lever is determined as engaged at step 518 then the method may proceed to step 521. At step 521, the leakage detection module 214 may determine if the hand brake lever has been engaged for a time period greater than the predefined pause period (tp). In an embodiment, the predefined pause period may be equal to or greater than 5 sec. In case, at step 521 it is determined that the hand brake lever has been engaged for a time period greater than the predefined pause period, the leakage detection module 214 may determine leakage in the pneumatic brake system 120 at step 522. Further, in case, at step 521 it is determined that the hand brake lever has been engaged for a time period less than the predefined pause period, the leakage detection module 214 may determine no leakage may be determined at step 520.
After determining the first differential pressure rate value (?P)f, the method may include the next step 508, in which the leakage determination module 214 may determine whether the first differential pressure rate value (?P)f may exceed the leakage threshold (Pth). Accordingly, after the determination of the second differential pressure rate value (?P)r, the method may proceed to step 510, in which the leakage determination module 214 may determine whether the second differential pressure rate value (?P)r may exceed the leakage threshold (Pth). Also, after the third differential pressure rate value (?P)p may be determined, the method may proceed to next step 512, in which the leakage determination module 214 may determine whether the second differential pressure rate value (?P)r may exceed the leakage threshold (Pth).
In an embodiment, if the first differential pressure rate value (?P)f may not exceed the leakage threshold, the method may proceed to step 510 to determine whether the second differential pressure rate value (?P)r may exceed the leakage threshold (Pth). Further, if the second differential pressure rate value (?P)r may not exceed the leakage threshold (Pth), the method may proceed to step 512 to determine whether the third differential pressure rate value (?P)r may exceed the leakage threshold (Pth). Further, when the third differential pressure rate value (?P)r may not exceed the leakage threshold (Pth), then no leakage may be determined at step 520.
If any of the first differential pressure rate value (?P)f, the second differential pressure rate value (?P)r, or the third differential pressure rate value (?P)p exceeds the leakage threshold (Pth) at steps 508, 510, or 512 respectively, the method may proceed to step 516. At step 516, the leakage detection module 214 may determine whether the brake pedal is pressed or unpressed. If the brake pedal is unpressed at step 516, the leakage detection module 214 may determine if the state of the hand brake lever is disengaged or engaged at step 518. In case at step 518, it is determined that the state of the hand brake lever is disengaged, then leakage detection module 214 may determine a leakage in the corresponding the front brake circuit 116, the rear brake circuit 118, or the parking brake circuit 120 of the pneumatic brake system 114 at step 522.
Further, if the brake pedal is pressed at step 516, the leakage detection module 214 may determine no leakage at step 520. Further, in the state of hand brake lever is determined as engaged at step 518 then the method may proceed to step 521. At step 521, if the hand brake lever has been engaged for a time period greater than the predefined pause period (tp) then the leakage detection module 214 may determine leakage in step 522. In case, at step 521 it is determined that the hand brake lever has been engaged for a time period less than the predefined pause period, no leakage is determined at step 520.
Further, at step 524, the alert module 216 may display an alert on a display of the vehicle depicting that a leakage may be present in the front brake circuit 116, the rear brake circuit 118, the parking brake circuit 120 or the pneumatic brake system 114 of the vehicle in case of determination of a leakage at step 522.
Accordingly, the determination of leakage in accordance with the flowcharts 300, 400 and 500, the leakage in the first condition, the second condition and the third condition may be determined effectively. Accordingly, based on the detection of leakage in the pneumatic brake system 114, the robustness of the braking system 114 may be enhanced.
With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.
It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as "open" terms (e.g., the term "including" should be interpreted as "including but not limited to," the term "having" should be interpreted as "having at least," the term "includes" should be interpreted as "includes but is not limited to," etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles "a" or "an" limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases "one or more" or "at least one" and indefinite articles such as "a" or "an" (e.g., "a" and/or "an" should typically be interpreted to mean "at least one" or "one or more"); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of "two recitations," without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to "at least one of A, B, and C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, and C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to "at least one of A, B, or C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, or C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase "A or B" will be understood to include the possibilities of "A" or "B" or "A and B." Ranges can be expressed herein as from "about" one particular value, and/or to "about" another particular value. When such a range is expressed, another aspect includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent "about," it will be understood that the particular value forms another aspect. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint.
In addition, where features or aspects of the disclosure are described in terms of Markush groups, those skilled in the art will recognize that the disclosure is also thereby described in terms of any individual member or subgroup of members of the Markush group.
While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.
, Claims:CLAIMS
I/We Claim:
1. A method for detecting air leakage in pneumatic brake system (114) in a vehicle, comprising:
determining, by an air leakage detection device (104), a first differential pressure rate value of a front brake circuit (116), a second differential pressure rate value of a rear brake circuit (118) and a third differential pressure rate value of a parking brake circuit (120),
wherein the first differential pressure rate value, the second differential pressure rate value and the third differential pressure rate value are determined based on a change in pressure in a first predefined time period in pneumatic lines of the front brake circuit (116), the rear brake circuit (118), and the parking brake circuit (120) respectively;
determining, by the air leakage detection device (104), a sum of the first differential pressure rate value, the second differential pressure rate value and the third differential pressure rate value;
determining, by the air leakage detection device (104), a state of brake pedal and a state of hand brake lever;
determining, by the air leakage detection device (104), an ignition state of the vehicle;
upon determining, by the air leakage detection device (104), the state of brake pedal as unpressed, the state of hand brake lever as unpressed and the ignition state as ON:
determining, by the air leakage detection device (104), a leakage in the pneumatic brake system (114) in case the sum is greater than a leakage threshold value; and
displaying, by the air leakage detection device (104), an alert on an output device of the vehicle based on the determination of the leakage in the pneumatic brake system (114).

2. The method as claimed in claim 1, comprising:
upon determining, by the air leakage detection device (104), the ignition state as ON, the state of brake pedal as unpressed and the state of hand brake lever as disengaged:
determining, by the air leakage detection device (104), a leakage in the front brake circuit (116) in case the first differential pressure rate value is greater than the leakage threshold value; or
determining, by the air leakage detection device (104), a leakage in the rear brake circuit (118) in case the second first differential pressure rate value is greater than the leakage threshold value; or
determining, by the air leakage detection device (104), a leakage in the parking brake circuit (120) in case the third first differential pressure rate value is greater than the leakage threshold value; and
displaying, by the air leakage detection device (104), an alert on the output device of the vehicle based on the determination of the leakage in the front brake circuit (116) or the rear brake circuit (118) or the parking brake circuit (120).

3. The method as claimed in claim 1, comprising:
upon determining, by the air leakage detection device (104), the ignition state as ON, the state of brake pedal as unpressed and the state of hand brake as disengaged for a period more than a second predefined period:
determining, by the air leakage detection device (104), a leakage in the front brake circuit (116) in case the first differential pressure rate value is greater than the leakage threshold value; or
determining, by the air leakage detection device (104), a leakage in the rear brake circuit (118) in case the second first differential pressure rate value is greater than the leakage threshold value; or
determining, by the air leakage detection device (104), a leakage in the parking brake circuit (120) in case the third first differential pressure rate value is greater than the leakage threshold value; and
displaying, by the air leakage detection device (104), an alert on the output device of the vehicle based on the determination of the leakage in the front brake circuit (116) or the rear brake circuit (118) or the parking brake circuit (120).

4. The method as claimed in claim 1, comprising:
upon determining, by the air leakage detection device (104), the ignition state as OFF, the state of brake pedal as unpressed and the state of hand brake lever as engaged for a period more than a second predefined period:
determining, by the air leakage detection device (104), a leakage in the front brake circuit (116) in case the first differential pressure value is greater than the leakage threshold value; or
determining, by the air leakage detection device (104), a leakage in the rear brake circuit (118) in case the second first differential pressure value is greater than the leakage threshold value; or
determining, by the air leakage detection device (104), a leakage in the parking brake circuit (120) in case the third first differential pressure value is greater than the leakage threshold value; or
determining, by the air leakage detection device (104), the leakage in the pneumatic brake system (114) in case the sum is greater than the leakage threshold value; and
upon subsequent determining, by the controller, the ignition state as ON:
displaying, by the air leakage detection device (104), an alert on the output device of the vehicle based on the determination of the leakage in the front brake circuit (116) or the rear brake circuit (118) or the parking brake circuit (120) or the pneumatic brake system (114).

5. The method as claimed in claim 1, wherein the first differential pressure rate value, the second differential pressure rate value and the third differential pressure rate value respectively are determined based on determination of a plurality of instantaneous pressure values over the first predefined time period of the pneumatic lines of the front brake circuit (116), the rear brake circuit (118), and the parking brake circuit (120) respectively, and
wherein the plurality of instantaneous pressure values over the first predefined time period are received from a sensor unit.

6. An air leakage detection device (104) for detecting an air leakage in pneumatic brake system (114) in a vehicle, the air leakage detection device (104) comprising:
a processor (106); and
a memory (108) coupled to the processor (106),
wherein the memory (108) stores a first set of instructions, which, on execution, causes the processor (106) to:
determine a first differential pressure rate value of a front brake circuit (116), a second differential pressure rate value of a rear brake circuit and a third differential pressure rate value of a parking brake circuit (120),
wherein the first differential pressure rate value, the second differential pressure rate value and the third differential pressure rate value are determined based on a change in pressure in a first predefined time period in pneumatic lines of the front brake circuit (116), the rear brake circuit, and the parking brake circuit (120) respectively;
determine a sum of the first differential pressure rate value, the second differential pressure rate value and the third differential pressure rate value;
determine a state of brake pedal and a state of hand brake lever;
determine an ignition state of the vehicle and a real-time speed of the vehicle;
upon determination of the state of brake pedal as unpressed, the state of hand brake as unpressed and the ignition state as ON:
determine a leakage in the pneumatic brake system (114) in case the sum is greater than a leakage threshold value; and
display an alert on an output device of the vehicle based on the determination of the leakage in the pneumatic brake system (114).

7. The device (104) as claimed in claim 6, wherein the processor is configured to:
upon determination of the ignition state as ON, the state of brake pedal as unpressed and the state of hand brake lever as disengaged:
determine a leakage in the front brake circuit (116) in case the first differential pressure rate value is greater than the leakage threshold value; or
determine a leakage in the rear brake circuit in case the second first differential rate pressure value is greater than the leakage threshold value; or
determine a leakage in the parking brake circuit (120) in case the third first differential pressure rate value is greater than the leakage threshold value; and
display an alert on the output device of the vehicle based on the determination of the leakage in the front brake circuit (116) or the rear brake circuit or the parking brake circuit (120).

8. The device (104) as claimed in claim 6, wherein the processor is configured to:
upon determination of the ignition state as ON, the state of brake pedal as unpressed and the state of hand break as disengaged for a period more than a second predefined period:
determine a leakage in the front brake circuit (116) in case the first differential pressure rate value is greater than the leakage threshold value; or
determine a leakage in the rear brake circuit in case the second first differential pressure rate value is greater than the leakage threshold value; or
determine a leakage in the parking brake circuit (120) in case the third first differential pressure rate value is greater than the leakage threshold value; and
display an alert on the output device of the vehicle based on the determination of the leakage in the front brake circuit (116) or the rear brake circuit or the parking brake circuit (120).

9. The device (104) as claimed in claim 6, wherein the processor is configured to:
upon determination of the ignition state as OFF, the state of brake pedal as unpressed and the state of hand brake lever as engaged for a period more than a second predefined period:
determine a leakage in the front brake circuit (116) in case the first differential pressure rate value is greater than the leakage threshold value; or
determine a leakage in the rear brake circuit in case the second first differential pressure rate value is greater than the leakage threshold value; or
determine a leakage in the parking brake circuit (120) in case the third first differential pressure rate value is greater than the leakage threshold value; or
determine the leakage in the pneumatic brake system (114) in case the sum is greater than the leakage threshold value; and
upon subsequent determination of the ignition state as ON:
display an alert on the output device of the vehicle based on the determination of the leakage in the front brake circuit (116) or the rear brake circuit or the parking brake circuit (120) or the pneumatic brake system (114).

10. The device (104) as claimed in claim 6, wherein the first differential pressure rate value, the second differential pressure rate value and the third differential pressure rate value respectively are determined based on determination of a plurality of instantaneous pressure values over the first predefined time period of the pneumatic lines of the front brake circuit (116), the rear brake circuit, and the parking brake circuit (120) respectively, and
wherein the plurality of instantaneous pressure values over the first predefined time period are received from a sensor unit.