Patent Application
20230415510
The present disclosure relates to a device for optimizing the grip of a tire fitted to a mobile vehicle traveling on a road surface. It also relates to a method for optimizing the grip implemented in this device, as well as motor vehicles and aircraft incorporating such a device.
The road surfaces concerned may be wet, cold, snowy or icy ground or any other variant whose disrupting element present on the grip surface can be vaporized or diverted. The transport sectors targeted include automotive sectors as well as those of civil and military aeronautics or any sectors using traveling vehicles equipped with tires. The device also has an advantage in improving the performance of a vehicle, in particular, in motor sport and when striving for high-performance.
Safety systems are already available such as ABS, ESP or EBA in the context of a braking phase. ABS, or anti-lock braking system, prevents the wheels from locking and enables steering control to be maintained in the case of emergency braking. ESP, or electronic stability program, is a trajectory correction device in the event of loss of grip. Finally, EBA (for Emergency Brake Assist) is, just like ABS, particularly interesting within the scope of the present disclosure. This emergency brake assist detects the abnormally fast switch from the accelerator pedal to the brake pedal. It should be noted that these driving aids are practically absent from the world of motor racing.
Regarding acceleration phases, the prior art are methods aimed at reducing the power transmitted to the wheels in order to regain grip; Traction Control (TC) is an example.
The effectiveness of emergency braking or a sudden acceleration on wet road is, non-exhaustively, directly related to the tire used (type of rubber, wear, temperature, inflation pressure), to the quantity of water present on the bitumen and to its temperature, to the desired braking or acceleration power and to the electronic grip control system.
Methods have existed with the aim of removing the water present on the road surface upstream of the tire, in particular, using jets of compressed air. However, these inventions have not come to fruition in the automotive industry even though the experimental results on a compressed air system saw in excess of a 20% reduction in braking distances up to 90 km/h. This compressed air system was activated by a windshield wiper and embedded in DC fans housed in the wheel arches.
The objective of the present disclosure is to contribute to increasing the grip coefficient of a tire fitted to a mobile vehicle, by using a laser beam to vaporize the element limiting the grip on the road surface, both in a braking and acceleration phase.
This objective is achieved with a device for optimizing the grip of a tire fitted to a mobile vehicle traveling on a road, this device being on board the mobile vehicle and comprising:
The device according to the present disclosure thus aims to increase the grip performance of a tire fitted to a vehicle traveling on wet ground, during braking and acceleration phases. It also relates to cold, snowy or icy ground or any other variant whose disrupting element present on the grip surface can be vaporized using a laser. It is conceivable to apply the device to automotive sectors as well as to civil and military aeronautics or any other traveling vehicle.
The main role of the grip optimization device is to increase the grip coefficient of the tire by vaporizing and/or deflecting the water present on the road surface, in any form whatsoever. However, the present disclosure is not only limited to water (in any state whatsoever) but also to any other liquid capable of being diverted or vaporized in front of a tire.
The present disclosure has the advantage of increasing the grip without reducing performance during acceleration. This aspect is particularly advantageous in a motor racing setting or when striving for high-performance.
The processing and control means are preferably arranged to further process information received from at least one braking safety system fitted to the mobile vehicle.
The detection and characterization means can advantageously comprise a camera having an image-capture field directed toward a portion of road surface in front of the mobile vehicle.
These detection and characterization means may further comprise means for measuring or estimating the external temperature in the vicinity of the road.
The means for emitting a laser beam may comprise a laser optical module arranged under the mobile vehicle and arranged so as to project the laser beam onto a portion of road surface in front of a tire of the vehicle.
The means for emitting a laser beam can further comprise a laser source module controlled by the processing and control means and connected to the optical module by optical fiber means.
In a particular embodiment, the grip optimization device may further comprise means for cooling the laser source module. These cooling means may comprise a heat transfer fluid circuit.
The laser optical module can be arranged to scan a laser beam over the road surface according to a predetermined scanning trajectory.
The braking safety system can comprise an anti-lock braking system (ABS), an emergency braking assist system (EBA), or an electronic stability program (ESP).
The control and processing means can be connected to an electronic control unit (ECU) on the vehicle.
When the grip optimization device according to the present disclosure is implemented in a vehicle comprising a body to which the means for emitting the laser beam are attached, it can further comprise means for detecting body movement and for transmitting detection information to the control and processing means.
According to another aspect of the present disclosure, a method is proposed for optimizing the grip of a tire fitted to a mobile vehicle traveling on a road surface, comprising:
The method according to the present disclosure can further comprise a step for processing information received from at least one braking safety system fitted to the mobile vehicle.
The detection and characterization step can use a camera having an image-capture field directed toward a portion of road surface in front of the mobile vehicle.
The detection and characterization step may further comprise a measurement or an estimation of the external temperature in the vicinity of the road.
According to yet another aspect of the present disclosure, a motor vehicle is proposed incorporating a grip optimization device according to the present disclosure, this motor vehicle comprising:
According to yet another aspect of the present disclosure, an aircraft is proposed incorporating a grip optimization device according to the present disclosure, this aircraft comprising:
The main role of the grip optimization device is to increase the grip coefficient of the tire by using a laser beam to vaporize the water present on the road surface, in any form whatsoever. However, the present disclosure is not only limited to water.
Water can be in different physical states: rain, snow, ice; only the optical absorption coefficient will vary, the vaporization energy necessary is therefore directly related to the physical state of the water to be vaporized. Studying the water absorption coefficient (in cm−1) determines the wavelength of the laser to be used. The power will be dependent on the tire width, the vehicle speed, the ambient temperature and the quantity of water present on the road surface.
The present disclosure implements an electronically controlled laser source, from which exits a laser beam transmitted via optical fiber (transmission beam) to an optical module to obtain the effective laser beam. The data necessary for triggering the system is acquired by different sensors (cameras, thermometers, etc.) and via a connection to the ECU (Electronic Control Unit, an on-board system for controlling physical devices inside the vehicle) that can provide the information to activate existing grip control systems and thus cause the device to activate.
For safety reasons, any impact suffered by the vehicle must absolutely disconnect the device in order to prevent any risk to surrounding users.
In another version of the present disclosure, the laser source can be supplemented by a second system dedicated to deflecting a portion of the liquid water. This tandem system can implement a second remote action: high-pressure air jet, supersonic air jet, microwave cannon or any other technical solution that could remotely divert the disrupting element on the road surface upstream of the laser beam. This other version may equally well relate to motor vehicles as to aircraft.
The advantage of the deflection/ablation tandem lies in the possibility of making the device effective under harsher conditions, in particular, at higher speeds and/or if the quantity of water is high.
Since the grip optimization device according to the present disclosure generates heat, an efficient cooling system can be provided in order to guarantee optimal operating conditions. This cooling system can be independent of the cooling system of the vehicle.
The laser beam may have different effects, in particular, that of creating a plasma. Since instantaneous laser ablation of water is energy-consuming, an envisaged alternative with an ablation effect is the creation of a plasma so as to divert the water present in front of the tire, using a laser beam. The creation of a deflection shock wave is also envisaged to move the water away from the tire.
Other advantages and particularities of the present disclosure will become apparent on reading the detailed description of implementations and embodiments that are in no way exhaustive, and the following appended drawings:
Since these embodiments are in no way limiting, it will particularly be possible to consider variants of the present disclosure comprising only a selection of the features described or illustrated, subsequently isolated from the other features described or illustrated (even if this selection is isolated within a phase comprising other features), if this selection of characteristics is sufficient to confer a technical advantage or to differentiate the present disclosure from the prior art. This selection comprises at least one feature, preferably functional, without structural details, and/or with only a portion of the structural details if this portion alone is sufficient to confer a technical advantage or to differentiate the present disclosure from the prior art.
With reference to
The control and processing unit 1 controls a laser source module 13 that is supplied by an electrical power unit 11. This laser source module 13 emits a laser beam that is transmitted via an optical fiber 2 to an optical module 3 arranged in the bumper of the vehicle thus equipped and intended to direct a laser beam toward a portion of road surface upon the command of the control and processing unit 1.
With reference to
The laser source module 13 is cooled by a heat transfer fluid circuit comprising hydraulic pipes 41,42, a hydraulic pump 4 and a ventilated cooling radiator 5.
The effective laser beam 7 can vary in shape: it can thus be linear and parallel to the leading edge of the tire or else angled or else in the shape of a “V,” sine wave or any other shape that will enable its effectiveness to be optimized.
Then, in order to optimize the effectiveness of the laser beam on the ground, the focal distance between the lens block and the ground must remain within a low tolerance range. Indeed, the device according to the present disclosure can include feedback control of the focal distance as a function of the body movements. A braking phase will result in a movement where the front of the vehicle will lower a few centimeters; in contrast, an acceleration phase will lower the rear of the vehicle. It is then conceivable to apprehend the body movements in order to have a usable beam within its efficiency range.
As soon as the grip optimization device 10 is activated, a power current must be available very quickly from an electrical power unit 11 on board the vehicle. Depending on the type of vehicle, whether a combustion, electric or hybrid engine, the available current may be redirected from the auxiliary functions (on-board computer, Hi-Fi, comfort components) to the safety device 10.
Water can be in different physical states: rain, snow, ice; the vaporization energy necessary is therefore directly related to the physical state of the water to be vaporized. Studying the water absorption coefficient (in cm-1) determines the wavelength of the laser to be used.
With reference to
The optical power required will be dependent on the tire width, vehicle speed, ambient temperature and amount of water present on the road surface.
In a second embodiment illustrated by
Of course, the present disclosure is not limited to the embodiments that have just been described and numerous other embodiments can be envisaged without departing from the scope of the present disclosure. In particular, the different components of the grip optimization device fitted to a motor vehicle can be arranged in locations other than those described in
| Number | Date | Country | Kind |
|---|---|---|---|
| FR2010954 | Oct 2020 | FR | national |
| FR2111179 | Oct 2021 | FR | national |
This application is a national phase entry under 35 U.S.C. § 371 of International Patent Application PCT/FR2021/051848, filed Oct. 21, 2021, designating the United States of America and published as International Patent Publication WO 2022/090649 A1 on May 5, 2022, which claims the benefit under Article 8 of the Patent Cooperation Treaty to French Patent Application Serial No. FR2010954, filed Oct. 26, 2020 and to French Patent Application Serial No. FR2111179, filed Oct. 21, 2021.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/FR2021/051848 | 10/21/2021 | WO |
