MONITORING SYSTEM IN CASE OF HYDROPLANING”

CROSS-REFERENCE TO RELATED APPLICATIONS

This Patent Application claims priority from Italian Patent Application No. 102022000016080 filed on July 28, 2022, the entire disclosure of which is incorporated herein by reference.

TECHNICAL FIELD OF THE INVENTION

The present invention relates in general to automotive technologies to hinder hydroplaning onset in a motor vehicle.

The present invention finds application in any type of road vehicle, whether it is used for the transport of people or for the transport of goods.

BACKGROUND OF THE INVENTION

As is known, in recent years car manufacturers have invested considerable resources in researching advanced motor vehicle driving assistance/aid systems (Advanced Driver Assistance Systems - ADAS) to improve driving safety and comfort.

For this reason and due to the fact that they will help achieve the goals set by the European Union for reducing road accidents, ADAS are one of the fastest growing segments in the automotive sector and bound to become increasingly popular in the years to come.

The safety features of these systems are designed to avoid collisions and accidents by offering technologies warning drivers of potential problems, or to avoid collisions by implementing safeguard measures and taking control of the motor vehicles. Adaptive features can automate lighting, provide adaptive cruise speed control, automate braking, incorporate GPS/traffic signalling, connect smartphones, alert drivers of other motor vehicles of hazards, keep drivers in the correct lane, or show what is in blind spots.

ADAS technology is based on vision/camera systems, sensory systems, automotive data networks, Vehicle-to-Vehicle (V2V) or Vehicle -to-Infrastructure (V2I) communication systems. Next-generation ADAS will increasingly exploit wireless connectivity to offer added value to V2V or V2I communication.

Technological developments such as the integration of radars and cameras, and the fusion of sensors between multiple applications, are expected to result in cost reductions which could lead to a more significant penetration of ADAS in the market for compact vehicles. The end-point of these technological developments is usually defined as self-driving motor vehicles or autonomous motor vehicles.

Camera-based ADAS are a key component for further improvements in driving safety and comfort. While image sensors perform well in good weather conditions, their efficiency suffers from adverse environmental influences such as heavy rain, fog, snow, or mud.

The Applicant has found that the ADAS currently on the market, although satisfactory in many respects, still have room for improvement, in particular in terms of the assistance they can provide to drivers of motor vehicles in conditions of poor grip, especially in the presence of hydroplaning.

Indeed, as is well known, hydroplaning (“slipping on water”) is a phenomenon of floating of a vehicle moving on a layer of water extending over a road surface. More precisely, hydroplaning occurs when the water, typically rainwater, is in such quantity that there is no longer sufficient contact area between the wheels of the vehicle and the road surface, due to insufficient depth of the tread rails or to their particular conformation. This creates a cushion of water which, by placing itself between the tyres and the road surface, eliminates the friction between the two surfaces with a pressure such as to support the weight of the vehicle. If this happens, it is no longer possible to slow down or change the direction of the vehicle, which loses directionality and traction and still remains subject to the rules of physics, retaining the momentum and direction it had when the phenomenon was triggered. Hydroplaning can be partial when it involves only some of the wheels of a vehicle, causing understeer or oversteer problems, especially during cornering.

OBJECT ND SUMMARY OF THE INVENTION

Therefore, the object of the present invention is to provide an ADAS capable of hindering hydroplaning onset in a motor vehicle.

According to the present invention, an ADAS capable of hindering hydroplaning onset in a motor vehicle and a motor vehicle equipped with such an ADAS are therefore provided as claimed in the attached claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The attached figure shows a block diagram of an ADAS which can assist the driver of a motor vehicle in the presence of hydroplaning.

DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

The present invention will now be described in detail with reference to the attached figures in order to allow a skilled person to implement it and use it. Various modifications to the described embodiments will be readily apparent to those skilled in the art and the general principles described may be applied to other embodiments and applications without however departing from the protective scope of the present invention as defined in the attached claims. Therefore, the present invention should not be regarded as limited to the embodiments described and illustrated herein, but should be allowed the broadest protection scope consistent with the features described and claimed herein.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning commonly understood by one of ordinary skill in the art to which the invention belongs. In case of conflict, the present specification, including the definitions provided, will control. Furthermore, the examples are provided for illustrative purposes only and as such should not be construed as limiting.

In particular, the block diagrams included in the attached figures and described below are not to be understood as a representation of the structural features, i.e., construction restrictions, but must be understood as a representation of functional features, i.e., intrinsic properties of the devices defined by the effects obtained, that is to say functional restrictions, which can be implemented in different ways, so as to protect the functionalities thereof (operational capability).

In order to facilitate the understanding of the embodiments described herein, reference will be made to some specific embodiments and a specific language will be used to describe the same. The terminology used herein is used for the purpose of describing particular embodiments only and is not intended to limit the scope of the present invention.

The attached Figure shows a block diagram of an embodiment of an ADAS 1 designed to hinder hydroplaning onset in a motor vehicle 2.

The ADAS 1 comprises:

- an automotive sensory system 3 designed to output data such that they allow hydroplaning onset to be detected; and

- automotive electronic processing resources 4 designed to communicate, through an automotive on-board communication network, such as CAN, FlexRAy or others, with the automotive sensory system 3 to receive output data thereof and process the received data to detect hydroplaning onset and to intervene on one or different automotive systems of the motor vehicle 2 to hinder hydroplaning onset.

The automotive sensory system 3 may be based on any present and future sensory, physical, virtual and hybrid technology allowing the detection of hydroplaning onset.

By way of non-limiting example, an automotive sensory system suitable for the purpose could be the current automotive forward-looking vision system of the automotive electronic Lane Keeping and Lane Centering systems, which is arranged so as to monitor the road section in front of the motor vehicle 2 and could therefore also be used to monitor the conditions of the road section in front of the motor vehicle 2.

In addition to, or as an alternative to, the automotive forward-looking vision system, another automotive sensory system suitable for the purpose could be, for example, the current ultrasonic sensor system of the Park Assist system.

As an alternative to, or in support of, the above-mentioned systems, hydroplaning onset could be detected by means of a virtual sensory system based on a series of automotive quantities measured by a physical automotive sensory system or otherwise calculated based thereon and shared on the automotive CAN.

As regards hindering hydroplaning onset, it should be noted that what matters are the operations implemented by the automotive electronic processing resources 4 and not the hardware and software architectures with which this assistance is provided, to the point that this assistance could be provided through a concentrated architecture, i.e., by a single automotive electronic control unit, or through a distributed cooperative architecture, i.e., distributed among several automotive electronic control units in communication and in cooperation with each other, depending on the hardware and software architectures that the automotive manufacturer considers appropriate for providing such assistance.

For this reason, and also for descriptive and representative convenience, and without this being in any way construed as limiting the hardware and software architectures, purely by way of example, the implementation of the hydroplaningonset hindering functionality will be described and illustrated in the following description and in the attached Figure as being entirely entrusted to a single automotive electronic control unit.

In order to hinder hydroplaning onset, the automotive electronic processing resources 4 are first of all programmed to: receive from the automotive sensory system 3 data representative of the conditions of the road section in front of the motor vehicle 2; and

- process the received data to detect hydroplaning onset.

In order to detect hydroplaning onset, the automotive electronic processing resources 4 are particularly programmed to estimate, based on the received data, the degree of road grip of the motor vehicle 2, i.e., the degree of adhesion of the tyres of the motor vehicle 2 to the road surface, and to detect hydroplaning onset based on the estimated degree of road grip.

The automotive electronic processing resources 4 are further programmed to: - compute the hydroplaning onset (time) frequency;

- determine when the hydroplaning onset (time) frequency satisfies a predetermined operating condition, in particular when it is higher than a threshold frequency stored in the automotive electronic processing resources 4; and

- when the hydroplaning onset frequency is determined to satisfy the predetermined operating condition, intervene on an automotive electronic tyre pressure monitoring system 5.

As is well known, the tyre pressure monitoring system 5, known by the acronym TPMS, is an automotive system designed to continuously monitor the pressure of each tyre in a motor vehicle 2 and to warn the driver of the motor vehicle 2 of the need to inflate the tyres of the motor vehicle 2 to restore an optimal or recommended nominal tyre pressure when the pressure in one of the tyres changes, in particular when it decreases, by a predetermined amount from the nominal pressure value.

In order to operate in this way, the tyre pressure monitoring system 5 uses pressure sensors that are part of the automotive sensory system 3, which are associated with, in particular are inserted in, the tyre valves and are able to detect very small pressure differences, even in the order of just 0.1 bar.

The tyre pressure monitoring system 5 is designed to acquire the tyre pressure values of the motor vehicle 2 and to warn the driver of the motor vehicle 2 of the need to inflate the tyres to restore the nominal pressure values when the pressure variation, in particular the pressure loss, in one of the tyres of the motor vehicle 2 is greater than a threshold pressure variation, e.g. 0.3 bar, which is stored in an electronic control unit of the tyre pressure monitoring system 5 and can be the same for all the tyres of the motor vehicle 2 or different between tyres, e.g. one for the front tyres and one for the rear tyres.

Indeed, if the tyres of the motor vehicle 2 are less inflated than the respective nominal pressures, their water-evacuation ability is significantly reduced, resulting in a higher likelihood of hydroplaning onset, with the other surrounding conditions being equal. Therefore, a higher hydroplaning onset time frequency may be due to the pressure of one or more of the tyres of the motor vehicle 2 being below the nominal pressure, but whose variation is in any case lower than the threshold pressure variation stored in the electronic control unit of the tyre pressure monitoring system 5 and therefore considered acceptable by the tyre pressure monitoring system 5.

Therefore, according to the invention, when the hydroplaning onset frequency satisfies the above-mentioned predetermined condition, in particular, as mentioned above, is higher than a threshold frequency stored in the automotive electronic processing resources 4, the latter are programmed to intervene on the tyre pressure monitoring system 5 by recalibrating, particularly by reducing, the threshold pressure variation stored in the electronic control unit of the tyre pressure monitoring system 5 and beyond which the tyre pressure monitoring system 5 warns the driver of the motor vehicle 2 of the need to inflate the tyres of the motor vehicle 2 to restore the nominal pressure values.

This recalibration consequently causes the tyre pressure monitoring system 5 to intervene precociously or earlier than in the absence of this recalibration, resulting in the driver of the motor vehicle 2 being accordingly warned of the need to inflate the tyres of the motor vehicle 2 in order to restore their nominal pressure precociously or earlier than in the absence of this recalibration, thus allowing the tyres of the motor vehicle 2 to be kept more inflated than they would be in the absence of this intervention, thereby reducing hydroplaning onset frequency and the consequences thereof.

In one embodiment, the electronic processing and storage resources 4 are also conveniently programmed to:

- discriminate between different hydroplaning levels caused by different water levels on the road surface, for example a high or higher level of hydroplaning, a medium level of hydroplaning, and a low or lower level of hydroplaning;

- differentiate the intervention on the tyre pressure monitoring system 5 in the different hydroplaning levels, i.e., by recalibrating differently the threshold pressure variation(s) based on which the tyre pressure monitoring system 5 is configured to operate.

The advantages brought about by the present invention are readily apparent from the preceding description.

In particular, the present invention makes it possible to counteract the driving instability caused by hydroplaning by appropriately recalibrating the threshold pressures based on which the tyre pressure monitoring system is configured to operate, so as to cause it to intervene precociously or earlier than in the absence of this recalibration and to keep the tyre pressures at higher values, which reduce the hydroplaning onset frequency.