System and method for controlling a braking system for a vehicle, and braking system

Abstract

A control system (100) of a braking system for a vehicle is described comprising a braking control element (102), operable by means of a body part (P) of a driver, and a braking means (104). The control system (100) comprises proximity sensor means (106) arranged to acquire proximity data of said body part (P) with respect to the braking control element (102) and electronic control means (108) arranged to: - cause said braking system to perform a first predetermined braking preparation or braking assistance function, when said sensor means determine that the distance (d) between the body part of the driver and the braking control element (102) is less than or equal to a predetermined distance threshold and the approach speed is less than a predetermined speed threshold; - cause said braking system to perform a second predetermined braking preparation or braking assistance function, different from the first predetermined braking preparation or braking assistance function, when said sensor means determine that the distance (d) between the body part (P) of the driver and the braking control element (102) is less than or equal to the predetermined distance threshold and the approach speed is greater than or equal to the predetermined speed threshold. Also described are a braking system, a vehicle and a control method.

Description

[0001] System and method for controlling a braking system for a vehicle, and braking system

[0002] Technical field

[0003] This invention is generally in the field of systems and methods for braking vehicles; in particular, the invention relates to a control system of a braking system for a vehicle, a corresponding control method of a braking system for a vehicle, and a braking system.

[0004] Prior art

[0005] In the transport sector, there is an increasing need to provide the vehicle with safety systems adapted to increase the safety of the vehicle.

[0006] For example, modern vehicles may be equipped with safety functions related to vehicle braking, such as auto-braking functions in case of pedestrian detection or impending collision.

[0007] The purpose of these safety functions is to minimize the risk of accidents, for example by generating visual or audible signals to alert the driver of the vehicle, and / or by automatically actuating the braking system of the vehicle.

[0008] In order to further improve the performance of said safety functions, it would be necessary to be able to predict the intention of a driver of a vehicle to perform a braking action.

[0009] By being able to predict the intention to perform the braking action, it is possible to bring the braking system into the best possible condition. In this way, the braking action generated by the user by activating the braking control will be timely and effective.

[0010] For example, in the prior art, systems are known that are designed to determine the driver's intention to perform a braking action, which systems are based on detecting the release of an accelerator control. For example, "release of the accelerator control" may mean the case where the driver lifts his foot off an accelerator pedal. Disadvantageously, an approach based on release of the accelerator control is not reliable. For example, the monitoring of the release of the accelerator control may not be implemented when advanced driver assistance systems (ADAS) are active. In particular, for most ADAS, when activated, the accelerator control is not used by the driver of the vehicle.

[0011] Furthermore, the release of the accelerator control is not necessarily indicative of a real braking intention on the part of the driver. For example, a driver could release the braking control to cause the vehicle to coast or simply to decrease the speed of the vehicle by means of the engine brake, without the need to stop the vehicle through the actuation of the braking system.

[0012] In the prior art there are further solutions based on a different approach. Such further known systems base the detection of the intention to perform a braking action on measurements from geographic road data or data from sensor adapted to monitor the surrounding environment of the vehicle.

[0013] Disadvantageously, these additional systems also have significant limitations. For example, geographic road data may be determined based on measurements taken using a GPS installed on board the vehicle. It is well known that GPS-based systems may not provide accurate data or, indeed, may not provide any data when passing through areas not covered by a signal (e.g., tunnels). Furthermore, geographic-road-data-based systems would not be able to detect a possible emergency situation not indicated by such geographic road data. In fact, it would not be possible to update the geographic road data in real time. Furthermore, the geographic road data may indicate the presence of a curve or traffic light along the route of the vehicle, but would not be able to signal any sudden braking of an additional vehicle preceding the driver's vehicle.

[0014] On the other hand, with regard to the data on the environment surrounding the vehicle detected by the sensors, they may require a certain processing time before being able to determine a possible emergency situation in which braking is required. In this case, the driver may already have actuated the brake control independently before these systems have determined the driver's need to perform a braking action. Furthermore, it is known that the detections made by means of said sensors are not always reliable and may in some cases signal false situations of the need to brake or not signal real situations in which braking would actually be necessary.

[0015] It should also be noted that both solutions based on geographic road data and solutions based on data sensors of the environment surrounding the vehicle are in no way able to assess the user's intention to perform braking, as the data taken into consideration are not correlated to the driver's intention.

[0016] Summary of the invention

[0017] One object of this invention is therefore to provide solutions that allow the intention of a driver of a vehicle to perform a braking action to be predicted reliably, so that the braking system may be configured in the best possible condition to facilitate braking.

[0018] A further object is to provide solutions which make it possible to predict the intention of the driver of the vehicle to perform a braking action, even in the event of activation of the driver assistance systems, ADAS.

[0019] A still further object is to provide solutions which make it possible to determine whether the driver is intending to perform a normal braking action or an emergency braking action, so as to be able to configure the braking system in the best possible condition for the specific situation.

[0020] The aforesaid and other objects and advantages are achieved, according to one aspect of the invention, by a control system of a braking system for a vehicle having the features defined in claim 1, according to a further aspect of the invention, by a braking system having the features defined in claim 11, according to a further aspect of the invention, by a vehicle having the features defined in claim 12, and, according to yet another aspect of the invention, by a method for controlling a braking system for a vehicle having the features defined in claim 13. Preferred embodiments of the invention are defined in the dependent claims, the content of which is to be understood as an integral part of the present description.

[0021] Brief description of the drawings

[0022] The functional and structural features of some preferred embodiments of a control system of a braking system for a vehicle, a method for controlling a braking system for a vehicle, a braking system and a vehicle according to the invention will now be described. Reference is made to the accompanying drawings, wherein:

[0023] - Fig. 1 illustrates a first embodiment of a control system according to the present invention;

[0024] - Fig. 2 illustrates a further embodiment of a control system according to the present invention;

[0025] - Fig. 3 illustrates an example of braking means;

[0026] - Fig. 4 is a detail figure showing an exemplary distance between a brake pad and a brake disk.

[0027] Detailed description

[0028] Before explaining in detail a plurality of embodiments of the invention, it should be clarified that the invention is not limited in the application thereof to the design details and configuration of the components presented in the following description or shown in the drawings. The invention may assume other embodiments and be implemented or constructed in practice in different ways. It should also be understood that the phraseology and terminology have a descriptive purpose and should not be construed as limiting. The use of “include” and “comprise” and the variations thereof are intended to cover the elements set out below and the equivalents thereof, as well as additional elements and the equivalents thereof.

[0029] Referring initially to Figure 1, an embodiment of a control system 100 of a braking system for a vehicle will be described below.

[0030] The braking system comprises a braking control element 102 and braking means 104. The braking control element 102 is operable by means of a body part P of a driver of the vehicle. The braking control element is arranged to allow adjustment of a braking force generated by the braking means 104.

[0031] The control system comprises proximity sensor means 106 arranged to acquire proximity data of the body part P of the driver of the vehicle with respect to the braking control element 102 of the braking system in a predetermined region R adjacent to the braking control element 102 of the braking system.

[0032] For example, as may be seen in Fig. 1 and 2, when the vehicle is an automobile, truck or the like, the predetermined region R adjacent to the braking control element 102 of the braking system may be part of the provided area between the driver's seat and the braking control element 102 of the braking system, i.e., the brake pedal.

[0033] The control system 100 further comprises electronic control means 108 arranged for: a) determining a distance d between the body part P of the driver of the vehicle and the braking control element 102 of the braking system, based on the proximity data acquired by the proximity sensor means 106; b) determining an approach speed of the body part P of the driver of the vehicle to the braking control element 102 of the braking system, based on the proximity data acquired by the proximity sensor means 106.

[0034] The electronic control means 108 are further arranged to cause the braking system to perform a first predetermined braking preparation or braking assistance function, when the electronic control means 108 determine that the distance d between the body part of the driver of the vehicle and the braking control element 102 of the braking system is less than or equal to a predetermined distance threshold and the approach speed is less than a predetermined speed threshold.

[0035] For example, a braking preparation function may be understood to mean a function arranged to bring the braking system into a condition that is capable of reacting promptly to a possible braking command given by the driver without actually generating a braking force. For example, the term brake assistance function may refer to a function arranged to operate the braking system autonomously, before any reception of a braking command given by the driver, so as to automatically generate a braking force.

[0036] The electronic control means 108 are further arranged to cause the braking system to perform a second predetermined braking preparation or braking assistance function, different from the first predetermined braking preparation or braking assistance function, when the electronic control means 108 determine that the distance between the body part P of the driver of the vehicle and the braking control element 102 of the braking system is less than or equal to the predetermined distance threshold and the approach speed is greater than or equal to the predetermined speed threshold.

[0037] By monitoring the distance d between the body part of the driver of the vehicle and the braking control element 102, the driver's intention to perform a braking action may be checked. Monitoring also the approach speed makes it possible to check whether the driver is about to perform a normal braking action or an emergency braking action.

[0038] In particular, an approach speed higher than or equal to the predetermined speed threshold may indicate that the driver is intending to press the braking control element for an emergency braking action. A high approach speed is an indication that the driver urgently wishes to actuate the braking system.

[0039] Otherwise, an approach speed lower than the predetermined speed threshold may indicate that the driver is intending to press the braking control element for a normal braking action and not for emergency braking.

[0040] For example, from the proximity data acquired over time, it is possible to determine a displacement made by the body part within a time interval. In this case, for example, the approach speed could then be determined as a function of the determined displacement and the time interval considered.

[0041] For example, the electronic control means 108 may be or comprise at least one of: a processor, a microprocessor, a controller, a microcontroller, an FPGA, a PLC, or the like.

[0042] Preferably, as may be seen in Fig. 1, the proximity sensor means 106 may be arranged to be included in or associated with the braking control element 102. Or, as may be seen in Fig. 2, the proximity sensor means 106 may be arranged at a predetermined distance from the braking control element 102.

[0043] Preferably, the proximity sensor means 106 may comprise at least one of: an optical sensor, an ultrasonic sensor, a laser sensor, a lidar sensor or a vision system.

[0044] Preferably, the braking control element 102 may comprise at least one of: a pedal or a hand lever.

[0045] For example, when the braking control element 102 is a pedal, the body part monitored by the proximity sensor means may be a driver’s foot.

[0046] For example, when the braking element 102 is a hand lever, the body part monitored by the proximity sensor means may be a driver's hand.

[0047] Preferably, the braking system may be an electro-pneumatic braking system or an electromechanical braking system or a brake-by-wire braking system.

[0048] Preferably, as for example observable in Fig. 3, the braking means 104 of the braking system may comprise at least:

[0049] - a brake disk 300 comprising at least one braking surface 302; and

[0050] - a brake caliper 304 comprising at least one thrust element 306 adapted to push a brake pad 308 in contact with the braking surface 302.

[0051] The braking force generated by the braking means may therefore be generated by means of the friction force generated by the contact between the brake pad and the braking surface.

[0052] For example, each brake caliper may comprise multiple brake pads, e.g., 2 brake pads. In this case, the brake disk may also have two braking surfaces (e.g., two surfaces facing in opposite directions).

[0053] For example, the thrust element may comprise at least one of: a spring, a piston, a cylinder. For example, the thrust element may be hydraulically actuated by means of a braking fluid or electronically actuated by means of an electrical signal.

[0054] The first predetermined braking preparation or braking assistance function or the second predetermined braking preparation or braking assistance function may be a brake-pad 302 approach function. The brake-pad approach function may, in other words, be arranged to actuate the thrust element 306 so as to reduce the distance between the brake pad 308 and the braking surface 302.

[0055] Because the system that is the subject of the invention may be able to predict an intention to perform a braking action, it may be possible to reduce the distance between the pads and the disk before the braking request occurs (i.e., before the driver actuates the braking control element), ensuring excellent readiness and feeling of the control element when the actual braking request occurs.

[0056] Preferably, with reference to Fig. 4, the approach function may comprise:

[0057] - checking whether a current distance X between the brake pad and the braking surface is greater than a predetermined minimum distance Xmin;

[0058] - if the current distance X is greater than the minimum distance Xmin, actuating the thrust element 306 so as to reduce the current distance X between the brake pad 308 and the braking surface 302, until said minimum distance Xmin is reached.

[0059] In other words, if the distance between the brake pad 308 and the braking surface 302 is already reduced, i.e., less than or equal to the predetermined minimum distance Xmin, it would not be necessary to bring the brake pad closer to the braking surface.

[0060] For example, the two actions listed above (checking and actuation) may be performed directly by the electronic control means 108 of the control system or by a further control module of the braking system in response to commands received from the electronic control means 108 of the control system.

[0061] The readiness of the braking system may depend mainly on the features of the braking system (including any servo-assist part) and on the distance between the at least one brake pad and the brake disk before braking: the closer the pads are to the disk, the more immediate the brake response will be. However, the excessive proximity of the pads with respect to the disk generally may cause unwanted contact between the pad and the disk even when braking force is not required, thus causing unwanted braking torque (called residual torque) and an increase in vehicle consumption. Considering a minimum distance between brake pad and disk may ensure good performance in terms of residual torque, ensuring the necessary minimum distance between pads and disk.

[0062] Preferably, the braking system may be arranged to generate the braking force in accordance with a braking characteristic between an intensity of activation of the braking control element 102 by the driver and the braking force generated by the braking means 104.

[0063] In this case, the first predetermined braking preparation or braking assistance function or the second predetermined braking preparation or braking assistance function may be a variation function of the braking characteristic. In other words, the variation function of the braking characteristic is arranged to vary the braking characteristic so as to increase the braking force generated by the braking means 104 in response to the intensity of activation of the braking control element 102 by the driver.

[0064] According to the present invention, by means of the first predetermined braking preparation or braking assistance function and / or the second predetermined braking preparation or braking assistance function, it will therefore be possible to obtain an excellent compromise between the residual torque and the braking system actuation readiness / speed. Brake actuation readiness may be understood to mean the feature of the braking system of ensuring a rapid (low response time) and consistent (rapid increase in braking force) braking response, following actuation of the braking control element, ensuring a good feeling for the driver and transmitting safety. Preferably, with reference to embodiments wherein the braking means comprise a brake disk 300 comprising at least one braking surface 302 and a brake caliper 304 comprising at least one thrust element 306 adapted to push a brake pad 308 in contact with the braking surface 302, when the electronic control means 108 determine that the distance d between the body part of the driver of the vehicle and the braking control element 102 of the braking system is greater than the predetermined distance threshold, the electronic control means 108 may be arranged to cause said braking system to perform a brake pad distancing function. The brake pad distancing function is arranged to control said thrust element 306 so as to increase the distance between said brake pad 308 and said braking surface 302.

[0065] Preferably, the brake pad distancing function may comprise:

[0066] - checking whether a current distance X between the brake pad and the braking surface is less than or equal to a predetermined minimum distance Xmin;

[0067] - if the current distance X is less than or equal to the minimum distance Xmin, controlling the thrust element 306 so as to increase the current distance X between the brake pad 308 and the braking surface 302.

[0068] For example, the two actions listed above (checking and actuation) may be performed directly by the electronic control means 108 of the control system or by a further control module of the braking system in response to commands received from the electronic control means 108 of the control system.

[0069] For example, the current distance X between the brake pad 308 and the braking surface 302 may be increased until it is greater than said minimum distance Xmin or until it reaches a predetermined move-away distance.

[0070] In one example, the first predetermined braking preparation or braking assistance function may be the brake-pad approach function and the second predetermined braking preparation or braking assistance function, different from the first predetermined braking preparation or braking assistance function, may be the variation function of said braking characteristic, or vice versa. Preferably, the electronic control means 108 may be further arranged for:

[0071] - interrupting the execution of the first predetermined braking preparation or braking assistance function by the braking system when the electronic control means 108 determines, on the basis of said proximity data acquired by said proximity sensor means 106, that the body part P of the driver is actuating said braking control element 102.

[0072] In other words, if the user is already operating the braking command, it may no longer be necessary to perform the first predetermined braking preparation or braking assistance function, as the braking action would already be in progress.

[0073] In a further aspect, the present invention relates to a braking system for a vehicle.

[0074] This braking system comprises:

[0075] - braking means;

[0076] - a braking control element arranged to allow adjustment of a braking force generated by the braking means.

[0077] The braking system further comprises a control system of a braking system for a vehicle, according to any one of the embodiments described above.

[0078] In a further aspect, the present invention relates to a vehicle. Such a vehicle comprises a braking system according to the embodiments described above.

[0079] In yet another aspect, the present invention relates to a method for controlling a braking system for a vehicle.

[0080] Also in this case, the braking system comprises a braking control element operable via a body part of a driver of the vehicle and braking means. The braking control element is arranged to allow adjustment of a braking force generated by said braking means.

[0081] The control method comprises the steps of: - acquiring proximity data of the body part of the driver of the vehicle with respect to the braking control element of the braking system in a predetermined region adjacent to the braking control element of the braking system;

[0082] - determining a distance between the body part of the driver of the vehicle and the braking control element of the braking system, based on proximity data acquired from the proximity sensor means;

[0083] - determining an approach speed of the body part of the driver of the vehicle to the braking control element of the braking system, based on proximity data acquired by the proximity sensor means;

[0084] - causing the braking system to perform a first predetermined braking preparation or braking assistance function, when it has been determined that the distance between the body part of the driver of the vehicle and the braking control element of the braking system is less than or equal to a predetermined threshold and the approach speed is less than a predetermined speed threshold;

[0085] - causing the braking system to perform a second predetermined braking preparation or braking assistance function, different from the first predetermined braking preparation or braking assistance function, when it has been determined that the distance between the body part of the driver of the vehicle and the braking control element of the braking system is less than or equal to a predetermined distance threshold and the approach speed is greater than or equal to a predetermined speed threshold.

[0086] The present invention may be applied to any type of vehicle. By way of non-limiting example, according to the present invention the vehicle may be a road vehicle, such as an automobile, a heavy truck used for transporting goods, a motorcycle, etc.

[0087] The advantage achieved is that of having provided solutions that make it possible to:

[0088] - reliably predict the intention of a driver of a vehicle to perform a braking action, so as to be able to configure the braking system in the best possible condition to facilitate braking;

[0089] - predict the intention of a driver of a vehicle to perform a braking action, even when driver assistance systems, ADAS, are activated;

[0090] - determine whether the driver is intending to perform a normal braking action or an emergency braking action, so that the braking system may be configured in the best possible condition to facilitate braking in light of the specific situation to be addressed.

[0091] Various aspects and embodiments of a control system of a braking system for a vehicle, a control method of a braking system for a vehicle, a braking system and a vehicle according to the invention have been described. It is understood that each embodiment may be combined with any other embodiment. Moreover, the invention is not limited to the embodiments described, but may be varied within the scope defined by the appended claims.

Claims

CLAIMS1. A control system (100) of a braking system for a vehicle, wherein said braking system comprises a braking control element (102) operable via a body part (P) of a driver of the vehicle and braking means (104), wherein said braking control element (102) is arranged to allow adjustment of a braking force generated by said braking means (104); wherein, said control system (100) comprises:- proximity sensor means (106) arranged to acquire proximity data of said body part (P) of the driver of the vehicle with respect to said braking control element (102) of said braking system, in a predetermined region (R) adjacent to said braking control element (102) of said braking system;- electronic control means (108) arranged for: a) determining a distance (d) between said body part (P) of the driver of the vehicle and said braking control element (102) of the braking system, based on the proximity data acquired by said proximity sensor means (106) b) determining an approach speed of said body part (P) of the driver of the vehicle to said braking control element (102) of the braking system, based on the proximity data acquired by said proximity sensor means (106); wherein, said electronic control means (108) are arranged to cause said braking system to perform a first predetermined braking preparation or braking assistance function, when said electronic control means (108) determine that the distance (d) between the body part of the driver of the vehicle and said braking control element (102) of the braking system is less than or equal to a predetermined distance threshold and the approach speed is less than a predetermined speed threshold; wherein, said electronic control means (108) are arranged to cause said braking system to perform a second predetermined braking preparation or braking assistance function, different from the first predetermined braking preparation or braking assistance function, when said electronic control means (108) determine that the distance (d) between the body part (P) of the driver of the vehicle and the braking control element (102) of the braking system is less than or equal to the predetermined distance threshold and the approach speed is greater than or equal to the predetermined speed threshold.

2. Control system according to claim 1, wherein said proximity sensor means are arranged to:- be included in or associated with said braking control element; or- be arranged at a predetermined distance from said braking control element.

3. Control system according to claim 1 or 2, wherein said proximity sensor means comprise at least one of:- an optical sensor- an ultrasonic sensor;- a laser sensor;- a lidar sensor;- a vision system.

4. Control system according to any one of the preceding claims, wherein said braking control element comprises at least one of:- a foot pedal;- a hand lever.

5. Control system according to any one of the preceding claims, wherein said braking means (104) of the braking system comprise at least:- a brake disk (300) comprising at least one braking surface (302); and- a brake caliper (304) comprising at least one thrust element (306) adapted to push a brake pad (308) in contact with said braking surface (302); wherein said first predetermined braking preparation or braking assistance function or said second predetermined braking preparation or braking assistance function is a brakepad approach function; said brake-pad approach function being arranged to actuate said thrust element (306) so as to reduce the distance between said brake pad (308) and said braking surface (302).

6. Control system according to claim 5, wherein said approach function comprises:- checking whether a current distance (X) between said brake pad (308) and saidbraking surface (302) is greater than a predetermined minimum distance (Xmin);- if the current distance (X) is greater than the minimum distance (Xmin), actuating said thrust element (306) so as to reduce the current distance (X) between said brake pad (308) and said braking surface (302), until said minimum distance (Xmin) is reached.

7. Control system according to any one of the preceding claims, wherein said braking system is arranged to generate said braking force in accordance with a braking characteristic between an intensity of activation of the braking control element by the driver and the braking force generated by the braking means; wherein the first predetermined braking preparation or braking assistance function or the second predetermined braking preparation or braking assistance function is a variation function of said braking characteristic; wherein said variation function of said braking characteristic is arranged to vary said braking characteristic so as to increase the braking force generated by the braking means in response to the intensity of activation of the braking control element by the driver.

8. Control system according to any one of the preceding claims, wherein said electronic control means are further arranged to:- interrupt the execution of the first predetermined braking preparation or braking assistance function by said braking system, when said electronic control means determines on the basis of said proximity data acquired by said proximity sensor means, that the body part of the driver is actuating said braking control element.

9. Control system according to any one of claims 5 to 8, wherein, when the electronic control means (108) determine that the distance (d) between the body part of the driver of the vehicle and the braking control element (102) of the braking system is greater than the predetermined distance threshold, the electronic control means 108 are arranged to cause said braking system to perform a brake pad distancing function; said brake pad distancing function being arranged to control said thrust element (306) so as to increase the distance between said brake pad (308) and said braking surface (302).

10. Control system according to claim 9, wherein said brake pad distancing functioncomprises:- checking whether a current distance (X) between the brake pad and the braking surface is less than or equal to a predetermined minimum distance (Xmin);- if the current distance (X) is less than or equal to the minimum distance (Xmin), controlling the thrust element (306) so as to increase the current distance (X) between the brake pad 308 and the braking surface (302).

11. Braking system for a vehicle, comprising:- braking means;- a braking control element arranged to allow adjustment of a braking force generated by said braking means;- a control system of a braking system for a vehicle according to any one of the preceding claims.

12. Vehicle comprising a braking system according to claim 11.

13. A method for controlling a braking system for a vehicle, wherein said braking system comprises a braking control element operable by a body part of a driver of the vehicle and braking means, wherein said braking control element is arranged to allow adjustment of a braking force generated by said braking means; wherein said control method comprises the steps:- acquiring proximity data of said body part of the driver of the vehicle with respect to said braking control element of said braking system in a predetermined region adjacent to said braking control element of said braking system;- determining a distance between said body part of the driver of the vehicle and said braking control element of the braking system, based on the proximity data acquired by said proximity sensors means;- determining an approach speed of said body part of the driver of the vehicle to said braking control element of the braking system, based on the proximity data acquired by said proximity sensor means;- causing said braking system to perform a first predetermined braking preparation or braking assistance function, when it has been determined that the distance between saidbody part of the driver of the vehicle and said braking control element of the braking system is less than or equal to a predetermined threshold and the approach speed is less than a predetermined threshold speed;- causing said braking system to perform a second predetermined braking preparation or braking assistance function, different from the first predetermined braking preparation or braking assistance function, when it has been determined that the distance between the body part of the driver of the vehicle and the braking control element of the braking system is less than or equal to a predetermined distance threshold and the approach speed is greater than or equal to a predetermined speed threshold.

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