Claims:WE CLAIM:
1. A braking control system (100) for rear wheels of a vehicle, said system (100) comprising:
i. At least one brake actuator (20a, 20b) configured to actuate brakes of said rear wheels;
ii. A wheel angle sensor (30) configured to sense the turning angle of the wheels and to generate a sensed signal based on said sensed turning angles; and
iii. A braking controller (10) configured to receive said sensed signal from said wheel angle sensor (30) and to actuate said brake actuator (20a, 20b) to reduce space usage on the headland in the field during a turning manoeuvre.
2. The braking control system (100) as claimed in claim 1, wherein said braking controller (10) comprises:
i. a repository configured to store a plurality of steering angle threshold values and a plurality of braking force values;
ii. a comparator communicatively cooperating with said repository, said comparator configured to compare said received signal with said steering angle threshold values to generate comparison signals; and
iii. an actuator control module communicatively cooperating with said comparator module and to control power supply to said brake actuators (20a, 20b) based on said comparison signals received from the comparator module.
3. The braking control system (100) as claimed in claim 2, wherein said repository is configured to store a first steering angle threshold, a second steering angle threshold that is greater than said first steering angle threshold, a first braking force value corresponding to said first steering angle threshold, and a second braking force value corresponding to said second steering angle threshold.
4. The braking control system (100) as claimed in claim 2, wherein said comparator is configured to generate a first comparison signal when said sensed turning angle is less than said first steering angle threshold value, a second comparison signal when said sensed turning angle is greater than or equal to said first steering angle threshold value and less than said second steering angle threshold value, and a third comparison signal when said sensed turning angle is greater than or equal to said second steering angle threshold value.
5. The braking control system (100) as claimed in claim 2, wherein said actuator control module configured to exert a first braking force on receipt of said second comparison signal, to increase said braking force proportional to said sensed turning angle and to exert said second braking force on receipt of said third comparison signal.
6. The braking control system (100) as claimed in claim 1, wherein said braking controller (10) is configured to actuate said brake actuator (20a, 20b) to exert differential forces on said brakes based on direction of steering during said steering manoeuvre.
7. The braking control system (100) as claimed in claim 1, wherein said braking controller (10) is configured to control a lifting motor (25) that is configured to actuate lifting and lowering of an agricultural implement coupled to said vehicle.
8. The braking control system (100) as claimed in claim 7, wherein said braking controller (10) is configured to control said lifting motor (25) while at least one of said brake actuators (20a, 20b) is being controlled by said braking controller (10).
9. The braking control system (100) as claimed in claim 1, which includes a brake latch switch (45) configured to be actuated by operation of a manually operable brake latch, said brake latch switch (45) communicatively coupled to said braking controller (10), said brake latch switch (45) configured to disable said brake controller (10) when said brake latch switch (45) is enabled.
10. The braking control system (100) as claimed in claim 2, which includes a manually operable braking force control knob (42) that facilitates changing said braking force values.
11. The braking control system (100) as claimed in claim 2, which includes a manually operable threshold angle control knob (41) that facilitates changing said steering angle threshold values.
12. A method of braking rear wheels of a vehicle during a turning manoeuvre, said method comprising the steps of:
i. exerting a first braking force on said rear wheels by brakes actuated through brake actuators, when turning angle of the wheels crosses a first steering angle threshold value;
ii. increasing said braking force proportional to said sensed turning angle through said brake actuators; and
iii. exerting a second braking force through said brake actuators, when said turning angle crosses a second steering angle threshold value.
13. The method as claimed in claim 12, which includes the step of decreasing said braking force proportional to said sensed turning angle when said turning angle falls below said second steering angle threshold value.

14. The method as claimed in claim 12, which includes the step of lifting an agricultural implement that is attached to said vehicle during said turning manoeuvre.
, Description:FIELD
The present disclosure relates to the field of agricultural machines. Particularly, the present disclosure relates to the field of braking force control during turning on headlands.
DEFINITION
As used in the present disclosure, the following terms are generally intended to have the meaning as set forth below, except to the extent that the context in which they are used indicates otherwise.
HEADLAND: Headland is the strip of land that is left unploughed at the end limits of an agricultural field.
BACKGROUND
The background information herein below relates to the present disclosure but is not necessarily prior art.
In normal farming practice, when an operator drives an agricultural machine, he applies brakes on the inner wheels on headlands to turn the machine within as small an area as possible. This is done to prevent headland wastage, thereby, increasing productivity. The operator, by virtue of his experience or training, should judge the exact point of application and release of the brakes, as well as the amount of braking force required while turning on headlands. In addition, he should take the soil conditions, vehicle and implement dynamics into consideration and modulate the brakes accordingly. He should also give appropriate steering inputs to keep the machine along its intended trajectory. This causes fatigue to the operator and requires extremely skilled labour. Different headland turning patterns also consume a lot of time and wastage, besides increased soil compaction, thus reducing efficiency.
In places where landholdings are small, headland wastage significantly affects the farmer since the headland turning occurrences are frequent. Also, in lower horsepower farm machinery, of compact and sub-compact categories, turning radius is greater than that of the implement. Due to these two factors, a major area of the land is wasted during headland turns in case of small landholdings.
In areas where the farm sizes are large, the implement sizes are large as well, which dictates the turning radius of vehicle. In other words, the turning radius of the vehicle is smaller than that of the implement. This prevents headland turn wastage from manifesting. Due to the large size farms, the farmer can turn his vehicles at the headland in K or Y patterns. Hence, essentially, headland turn braking is not required. Although a manual Y-Type or K-type turn technically solves the problem, it also requires great precision by the driver and at the same time induces a lot of fatigue. Altogether, it decreases the efficiency of the driver/farmer.
Therefore, a system is required for automatic braking of an agricultural machine intelligently during headland turns, which not only reduces the turning radius but also reduces the fatigue of the operator.
OBJECTS
Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:
A primary object of the present disclosure is to provide a braking control system for rear wheels of a vehicle during a turning manoeuvre.
Another object of the present disclosure is to provide a braking control system for rear wheels of a vehicle during a turning manoeuvre, which reduces the turning radius of the vehicle.
Yet another object of the present disclosure is to provide a braking control system for rear wheels of a vehicle during a turning manoeuvre, which is automatic.
Still another object of the present disclosure is to provide a braking control system for rear wheels of a vehicle during a turning manoeuvre, which reduces fatigue of the operator.
Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.
SUMMARY
The present disclosure envisages a braking control system for rear wheels of a vehicle. The system comprises at least one brake actuator, a wheel angle sensor and a braking controller. The brake actuator is configured to actuate brakes of the rear wheels. The wheel angle sensor is configured to sense the turning angle of the corresponding wheel and to generate a sensed signal based on the sensed turning angle. The braking controller is configured to receive signal from the sensor and to actuate the brake actuator to reduce space usage on the headland in the field during a turning manoeuvre.
In a preferred embodiment, the braking controller comprises a repository, a comparator module and an actuator control module. The repository is configured to store a plurality of steering angle threshold values and a plurality of braking force values. The comparator module is communicatively cooperating with the repository and is configured to compare the received signal with the steering angle threshold values and generate comparison signals. The actuator control module is communicatively cooperating with the comparator module and is configured to control power supply to the brake actuators based on comparison signals received from the comparator module.
In an embodiment, the repository is configured to store a first steering angle threshold, a second steering angle threshold that is greater than the first steering angle threshold, a first braking force value corresponding to the first steering angle threshold and a second braking force value corresponding to the second steering angle threshold. The comparator module is configured to generate a first comparison signal when the sensed turning angle is less than the first steering angle threshold value, a second comparison signal when the sensed turning angle is greater than or equal to the first steering angle threshold value and less than the second steering angle threshold value, and a third comparison signal when the sensed turning angle is greater than or equal to the second steering angle threshold value. The actuator control module is configured to exert a first braking force on receipt of the second comparison signal, to increase the braking force proportional to the sensed turning angle and to exert the second braking force on receipt of the third comparison signal.
Advantageously, the braking controller is configured to actuate the brake actuator to exert differential forces on the brakes based on direction of steering during the steering manoeuvre.
In a preferred embodiment, the braking controller is configured to control a lifting motor that is configured to actuate lifting and lowering of an agricultural implement coupled to the vehicle. Advantageously, the braking controller is configured to control the lifting motor before initiating control of the brake actuators controlled by the braking controller.
In a preferred embodiment, the system comprises a brake latch switch configured to be actuated by operation of a manually operable brake latch. The brake latch switch is communicatively coupled to the braking controller. The brake latch switch is configured to disable the brake controller when the brake latch switch is enabled.
In an embodiment, the system comprises a manually operable braking force control knob for changing the braking force values.
In an embodiment, the system comprises a manually operable threshold angle control knob for changing the steering angle threshold values.
Also envisaged is a method of braking rear wheels of a vehicle during a turning manoeuvre. The method comprises the steps of:
i. exerting a first braking force on the rear wheels by brakes actuated through brake actuators when turning angle of the wheels crosses a first steering angle threshold value;
ii. increasing the braking force proportional to the sensed turning angle through the brake actuators; and
iii. exerting a second braking force through the brake actuators, when the turning angle crosses a second steering angle threshold value.
The method includes the step of decreasing the braking force proportional to the sensed turning angle when the turning angle falls below the second steering angle threshold value.
The method also includes the step of lifting an agricultural implement that is attached to the vehicle before initiating the turning manoeuvre.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
A braking control system for rear wheels of a vehicle during a turning manoeuvre, of the present disclosure, will now be described with the help of the accompanying drawing, in which:
Figure 1 shows the various types of turns that can be executed on headlands with conventional techniques;
Figure 2 is a block diagram of the braking control system according to an embodiment of the present disclosure;
Figure 3 is a block diagram of the braking control system according to another embodiment of the present disclosure;
Figure 4 is a flowchart for operation of the braking control system of Figure 3; and
Figure 5 illustrates comparison of trajectories for a vehicle making a turning manoevre without braking and with the braking control system of the present disclosure activated.
LIST OF REFERENCE NUMERALS
h0 turning boundary for a broader headland
h0’ turning boundary for a narrower headland
h1 field boundary
H headland size
100 braking control system
10 braking controller
20a left brake actuator
20b right brake actuator
25 electric quick lift motor
30 wheel angle sensor
40 control panel
41 threshold angle control knob
42 braking force control knob
43 range switch
44 electric quick lift switch
45 brake latch switch
46 status indicator
DETAILED DESCRIPTION
Embodiments, of the present disclosure, will now be described with reference to the accompanying drawing.
Embodiments are provided so as to thoroughly and fully convey the scope of the present disclosure to the person skilled in the art. Numerous details are set forth, relating to specific components, and methods, to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail.
The terminology used, in the present disclosure, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. As used in the present disclosure, the forms “a”, “an” and “the” may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms “comprises”, “comprising”, “including” and “having” are open ended transitional phrases and therefore specify the presence of stated features, elements, modules, units and/or components, but do not forbid the presence or addition of one or more other features, elements, components, and/or groups thereof.
The terms first, second, third, etc., should not be construed to limit the scope of the present disclosure as the aforementioned terms may be only used to distinguish one element, component or section from another component or section. Terms such as first, second, third etc., when used herein do not imply a specific sequence or order unless clearly suggested by the present disclosure.
The operator of an agricultural vehicle has to often perform a U-turn over headlands of the field. When performed carefully to avoid headland wastage, such a manoeuvre requires skills and training, as it involves precise timing of application and release of brakes and judging of the braking force required. Moreover, soil conditions, vehicle and equipment dynamics also need to be considered. Steering also needs to be skillfully performed at the same time. Such a headland turning manoeuvre, therefore, causes fatigue to the operator. This is even more critical when the landholdings are small. Even in case of large-sized farms, where K-type, U-type, keyhole type or Y-type turns can eliminate the need of braking, they still are fatigue-inducing. Figure 1 shows the various types of turns that can be executed on headlands. Figure 1a shows a keyhole turn, Figure 1b shows a U-turn, Figure 1c shows a K-turn and Figure 1d shows a Y-turn. ‘h0’ is the turning boundary for a broader headland, ‘h0’’ is the turning boundary for a narrower headland, ‘h1’ is the field boundary and ‘H’ is the headland size.
Therefore, a system is required for automatic braking of an agricultural machine intelligently during headland turns, which reduces the turning radius, eliminates the need of performing various conventional complex turning manoeuvres and also reduces the fatigue of the operator.
The present disclosure envisages a braking control system 100 for rear wheels of a vehicle. The braking control system 100 and its various embodiments are described hereforth with the help of Figures 2 through 5. The braking control system 100 comprises at least one brake actuator, a wheel angle sensor 30 and a braking controller 10. The brake actuator, which may be a left brake actuator 20a or a right brake actuator 20b, is configured to actuate brakes of the rear wheels. The wheel angle sensor 30 is configured to sense the turning angle of the wheels. The braking controller 10 is configured to receive signal from the sensor and to actuate the brake actuator to reduce space usage on the headland in the field during a turning manoeuvre.
Preferably, the brake actuators are fitted with feedback sensors which help the controller to modulate the brakes as required.
In a preferred embodiment, the braking controller 10 comprises a repository, a comparator and an actuator control module. The repository is configured to store a plurality of steering angle threshold values and a plurality of braking force values. The comparator module communicatively cooperates with the repository and is configured to compare the received signal with the steering angle threshold values. The actuator control module communicatively cooperates with the comparator module and is configured to control power supply to the brake actuators based on comparison signals received from the comparator module.
Specifically, the repository is configured to store a first steering angle threshold, a second steering angle threshold that is greater than the first steering angle threshold, a first braking force value corresponding to the first steering angle threshold, a second braking force value corresponding to the second steering angle threshold. The comparator is configured to generate a first comparison signal when the sensed turning angle is less than the first steering angle threshold value, a second comparison signal when the sensed turning angle is greater than or equal to the first steering angle threshold value and less than the second steering angle threshold value, and a third comparison signal when the sensed turning angle is greater than or equal to the second steering angle threshold value. The actuator control module is configured to control power supply to the brake actuators to exert a first braking force on receipt of the second comparison signal, to increase the braking force proportional to the sensed turning angle and to exert the second braking force on receipt of the third comparison signal.
Preferably, the braking controller 10 is configured to actuate the brake actuator to exert differential forces on the brakes based on direction of steering during the steering manoeuvre. In an embodiment, the braking control system comprises two brake actuators wherein a left brake actuator 20a actuates the left brake and a right brake actuator 20b actuates the right brake. The braking controller 10 actuates the left brake actuator 20a when the rear wheels of the vehicle turn on the left side beyond a predetermined steering angle threshold value, and actuates the right brake actuator 20b when the rear wheels of the vehicle turn on the right side beyond a predetermined steering angle threshold value.
In a preferred embodiment, the braking controller 10 is configured to control a lifting motor that is configured to actuate lifting and lowering of an agricultural implement coupled to the vehicle. Particularly, the braking controller 10 is configured to control the lifting motor before initiating control of the brake actuators 20a, 20b by the braking controller 10.
Preferably, the braking control system comprises a brake latch switch 45. The position of a brake latch is sensed by the brake latch switch. The brake latch is manually operable. When the brake latch switch 45 is enabled by operating the brake latch, the braking controller 10 is disabled. Therefore, the brakes are not applied when the vehicle is turned. Thus, the operator would prevent the automatic braking from being executed when the vehicle is turned over a normal land and not on a headland. In this way, the braking control system does not interfere with the normal working of the vehicle and can be switched ON/OFF when desired by the operator.
Further, a preferred embodiment of the braking control system comprises a manually operable braking force control knob 42 that facilitates changing the braking force values. The operator can vary the braking force values corresponding to the steering angle threshold values based on the soil conditions. Moreover, the braking control system comprises a manually operable threshold angle control knob 41 that facilitates changing the steering angle threshold values.
In an embodiment, the vehicle is provided with a control panel 40 houses the brake latch switch 45. The control panel 40 also houses a status indicator LED 46 indicating whether the brake latch switch 45 is ON or OFF. The control panel 40 further houses the braking force control knob 42 and the threshold angle control knob 41. The control panel 40 also houses an electric quick lift (EQL) switch 44 for allowing to manually lift or lower the implement attached to the agricultural vehicle through an EQL motor 25, and a range switch 43 that allows the braking controller 10 to detect the high speed and the low speed settings set by the user.
The present disclosure also envisages a method of braking for rear wheels of a vehicle during a turning manoeuvre, using the braking control system 100. The method comprising the steps of:
i. exerting a first braking force on the rear wheels by brakes actuated through the brake actuators when turning angle of the wheels crosses a first steering angle threshold value;
ii. increasing the braking force proportional to the sensed turning angle through the brake actuators; and
iii. exerting a second braking force through the brake actuators, when the turning angle crosses a second steering angle threshold value.
In an embodiment, the method comprises the step of decreasing the braking force proportional to the sensed turning angle when the turning angle falls below the second steering angle threshold value.
In an embodiment, the method comprises the step of lifting an agricultural implement that is attached to the vehicle during the turning manoeuvre.
The flowchart for operation of the most preferred embodiment of the braking control system is shown in Figure 4. The braking controller 10 checks whether the brake latch switch 45 is disabled, followed by looking for the steering angle, braking force and speed settings, after which it determines the direction of turning of the wheels of the vehicle, and applies braking force on the wheel corresponding to the detected direction of turning.
Effectively, as illustrated through Figure 5, the turning radius of the vehicle that is achieved by incorporating the braking control system of the present disclosure is significantly smaller that the turning radius achieved by manually performing the turning manoeuvre on a headland. A0 being the headland area and T0 being the trajectory of the agricultural vehicle while manually turning on the headland, the area A1 is related to the reduction in headland wastage achieved by following the trajectory T1 using the braking control system of the present disclosure. Typically, manual turning gives a turning radius of 9m, whereas the braking control system of the present disclosure gives a radius of 5m.
The foregoing description of the embodiments has been provided for purposes of illustration and not intended to limit the scope of the present disclosure. Individual components of a particular embodiment are generally not limited to that particular embodiment, but, are interchangeable. Such variations are not to be regarded as a departure from the present disclosure, and all such modifications are considered to be within the scope of the present disclosure.
TECHNICAL ADVANCEMENTS
The present disclosure described herein above has several technical advantages including, but not limited to, the realization of a braking control system for rear wheels of a vehicle and a method of braking for rear wheels of a vehicle during a turning manoeuvre, that:
• reduces the turning radius of the vehicle;
• does not interfere with the normal working of the vehicle and can be switched ON/OFF when desired by the operator;
• is automatic;
• improves productivity by reducing the time taken to negotiate the headland turn; and
• reduces fatigue of the operator.
The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein.
The foregoing description of the specific embodiments so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results.
While considerable emphasis has been placed herein on the components and component parts of the preferred embodiments, it will be appreciated that many embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other changes in the preferred embodiment as well as other embodiments of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation