FR3061113A1 - METHOD FOR CONTROLLING A VIDEO-MIRROR SYSTEM FOR A MOTOR VEHICLE - Google Patents

Abstract

The invention relates to a method for controlling a video-mirror system (10) for a motor vehicle (1), comprising steps of: a) acquisition of a first parameter relating to the direction of travel of the motor vehicle, b) acquiring at least a second parameter relating to the manner in which the motor vehicle is driven, c) acquiring images of the environment at the rear of the motor vehicle, d) selecting, only part of the acquired images in step c), as a function of the first and second parameters acquired in steps a) and b), and e) displaying, on a screen (12) of the video-mirror system, the part only of the images selected in step d).

Description

Holder (s): simplified.

RENAULT S.A.S. Joint-stock company

O Extension request (s):

® Agent (s): RENAULT SAS.

® PROCESS FOR DRIVING A VIDEO REAR-VIEW MIRROR SYSTEM FOR A MOTOR VEHICLE.

FR 3,061,113 - A1 (57) The invention relates to a method for controlling a video mirror system (10) for a motor vehicle (1), comprising steps of:

a) acquisition of a first parameter relating to the direction of travel of the motor vehicle,

b) acquisition of at least one second parameter relating to the manner in which the motor vehicle is driven,

c) acquisition of images of the environment at the rear of the motor vehicle,

d) selection, of only part of the images acquired in step c), as a function of the first and second parameters acquired in steps a) and b), and

e) display, on a screen (12) of the video mirror system, of only the part of the images selected in step d).

Technical field to which the invention relates

The present invention relates generally to the field of driving aids for motor vehicles.

It relates more particularly to a method for controlling a video mirror system for a motor vehicle.

It also relates to a video mirror system and to a motor vehicle embedding such a system.

The invention finds a particularly advantageous application in models of motor vehicles which do not have a rear window.

Technological background

A motor vehicle is generally equipped with an interior mirror which allows the driver to have a good vision of the environment behind the motor vehicle.

A large part of the commercial vehicles unfortunately do not have a rear window, so that they are not equipped with such interior mirrors. Driving in reverse for these motor vehicles is therefore delicate and potentially dangerous.

To remedy these problems, it is already known to equip a utility vehicle with a camera oriented towards the driving scene at the rear of the vehicle and with a display screen which is in the form of a rear view mirror. interior suitable for displaying the images acquired by the camera.

Given the regulations regarding the shape and size of the interior mirrors, it is necessary to cut the acquired images at the bottom (and possibly also at the top), in order to be able to display them over the entire width of the rear view mirror screen.

This image cut-off then deprives the driver of near-environment vision at the rear of the vehicle. The view offered is therefore not optimal, especially when the vehicle is parked in reverse.

Object of the invention

In order to remedy the aforementioned drawback of the state of the art, the present invention proposes to modify the view displayed by the screen, as a function of different parameters, so that the view displayed can adapt to the vehicle driving phase.

More particularly, according to the invention, a method for controlling a video-rear view mirror system is proposed, comprising steps of:

a) acquisition of a first parameter relating to the direction of travel of the motor vehicle,

b) acquisition of at least one second parameter relating to the commands exerted by the driver on the motor vehicle,

c) acquisition of images of the environment at the rear of the motor vehicle (1) by at least one image sensor of the video mirror system,

d) selection, of only part of the images acquired in step c), according to the first and second parameters acquired in steps a) and b), and

e) display, on a screen of the video rearview mirror system, of only the part of the images selected in step d).

Thus, thanks to the acquired parameters, it is in particular possible to distinguish three situations:

- the one where the vehicle is in forward gear, which requires a high vision of the rear environment of the vehicle,

- one where the vehicle reverses at high speed, which also requires a high vision of the rear environment of the vehicle, and

- the one where the driver seeks to park the motor vehicle, which requires a low vision of the environment (like a reversing camera).

The invention then makes it possible to display on the display screen of the interior mirror a view considered to be the most useful for the driver, given the situation in which the vehicle is located.

Other advantageous and non-limiting characteristics of the piloting method according to the invention are as follows:

- the video rearview mirror system comprising a single image sensor, in step d), it is planned to select a part of each image acquired in step c);

- the video rearview mirror system comprising at least two image sensors, in step d), provision is made to select the images acquired by only one of the two image sensors;

- in step d), a part of the images is selected which represents either a low area of the environment seen in the near field, or a high area of the environment seen in the far field;

- Said second parameter includes the speed of the motor vehicle;

- Said second parameter comprises the position of the indicators of the motor vehicle and / or the angle of the steering wheel of the motor vehicle;

- Said second parameter further comprises one of the elements from the following list: a signal for detecting a lane change in the motor vehicle, a geolocated position for the motor vehicle, a signal for detecting an available parking space;

- there is a step of processing each image acquired in order to detect an obstacle, and, in step e), said obstacle is highlighted on the part of the images displayed.

The invention also relates to a video mirror system, comprising:

- an interior mirror fitted with a display screen,

- at least one image sensor, and

- A processing unit which is adapted to control the display of part of the images acquired by each image sensor on said display screen, and to implement a control method as mentioned above.

It also relates to a motor vehicle carrying such a video rearview mirror system.

Detailed description of an exemplary embodiment

The description which follows with reference to the appended drawings, given by way of nonlimiting examples, will make it clear what the invention consists of and how it can be carried out.

In the accompanying drawings:

- Figure 1 is a schematic side view of a motor vehicle equipped with a video mirror system according to the invention;

- Figure 2 is a schematic representation of an image acquired by a wide-angle image sensor of the video mirror system of Figure 1;

- Figure 3 is a schematic side view of an alternative embodiment of the motor vehicle of Figure 1;

- Figures 4 and 5 are schematic representations of two images acquired by two image sensors of the video mirror system of the motor vehicle of Figure 3.

As a preliminary, it will be noted that the identical or similar elements of the different embodiments of the invention shown in the different figures will, as far as possible, be referenced by the same reference signs and will not be described each time.

In FIG. 1, a motor vehicle 1 is shown.

In the description, the terms “front” and “rear” will be used with respect to this motor vehicle 1, the front designating the side towards which the vehicle is traveling when it is in forward gear and its wheels are straight, and the rear designating the opposite side.

This is a utility vehicle, but the invention could be applied to any other vehicle model.

This motor vehicle 1 conventionally comprises a chassis, a seat 7, wheels, a powertrain connected to the drive wheels by a transmission system, a steering wheel 2 connected to the steered wheels by a steering system, and bodywork elements delimiting a passenger compartment. 5 and a trunk 6.

Here, the chassis and bodywork are designed in such a way that the vehicle does not have a rear window (that is, a window at the rear of the vehicle). On the other hand, the chassis here has a partition which separates the passenger compartment 5 from the boot 6.

It is therefore understood that once seated in his seat 7, the driver will have no direct view of the environment located at the rear of the vehicle. He will only be able to observe part of the rear environment through the exterior mirrors located on either side of the vehicle.

In order to give it a better view of this rear environment, the motor vehicle 1 is equipped with a video mirror system 10.

It is generally a system which proposes to take advantage of the habits of drivers by placing an interior mirror in the passenger compartment of the vehicle, in the conventional position (in the center of the upper edge of the windshield), and by providing it with a screen displaying images of the rear environment.

As shown in FIG. 1, this video mirror system 10 comprises for this purpose an image sensor 11 oriented towards the rear of the vehicle, an interior mirror equipped with a display screen 12, and a processing unit adapted to control the display screen 12, taking into account the images acquired by the image sensor 11.

The processing unit 13 conventionally comprises a processor, a random access memory and a read only memory. The read-only memory stores in particular a computer application, made up of computer programs comprising instructions whose execution by the processor allows the implementation of the method which will be described below.

It will be considered here that the processing unit 13 is dedicated to driving the video mirror system 10, and that it is adapted to communicate with the main computer of the motor vehicle 1.

Alternatively, it could be an integral part of this main computer.

The display screen 12 is in turn formed by a flat screen, here a liquid crystal display (or LCD for Liquid Crystal Display) with thin film transistors (or TFT for Thin-Film Transistor). This display screen 12 is integrated into a conventional interior mirror shell and is covered by a protective glass.

The display screen 12 extends over a major part of the height of the hull of the interior mirror and over a major part of the width of this hull. It therefore has a very elongated shape: its width is at least twice greater than its height. It is therefore able to display panoramic images.

The image sensor is in turn formed by a conventional camera 11, which is fixed to the rear of the motor vehicle 1.

In the preferred embodiment of the invention shown in Figure 1, the video mirror system 10 comprises a single camera 11, which is equipped with a wide angle lens.

Typically, this camera 11 can be fixed to the chassis or to the body of the motor vehicle 1, in such a way that its optical axis is oriented towards the rear and downwards. This will include in the field of vision of the camera not only the horizon line but also the rear bumper 8 of the motor vehicle 1.

The wide-angle lens of the camera 11 can therefore have a viewing angle δ of between 95 and 125 degrees, for example equal to 110 degrees.

FIG. 2 shows an image 20 that this camera 11 is capable of acquiring. We can see both the horizon line 100 and the rear bumper 8 of the vehicle.

The camera 11 is qualified as classic in the sense that it is suitable for acquiring generally rectangular images 20, with proportions for example equal to 4/3 or 16/9.

Thus the display screen 12 of the interior mirror has very different proportions from those of images 20.

To display the image 20 on the display screen 12, one could use three different methods.

The first method would be to display the entire image 20 on the display screen 12, using only part of that screen. The image displayed would however be too small to be readable by the driver.

The second method would be to stretch the image 20 across the entire display screen 12, but the distortion caused would be unpleasant for the driver and even potentially dangerous.

The third method, which is that used in the present invention, consists in cutting the top and / or the bottom of the image 20, so as to display only part of the image 20 on the screen. display 12.

So that the part of the image 20 which is displayed always corresponds to that which the driver most needs to drive the motor vehicle 1 taking into account the maneuver which he performs, the processing unit 13 is adapted to bring into play work, in a loop, a process comprising five main stages, namely:

- a first step of acquiring a first parameter relating to the direction of travel of the motor vehicle 1,

- a second step of acquiring at least one second parameter (distinct from the first parameter) relating to the manner in which the motor vehicle 1 is driven by the driver of the motor vehicle 1,

a third step of acquiring images 20 of the environment at the rear of the motor vehicle 1,

a fourth step of selecting only part of the acquired image, according to the first and second parameters, and

- a fifth stage of display, on the display screen 12, of this part only of the image.

These five stages can be described in more detail.

During the first two steps, the processing unit 13 communicates with the main computer of the motor vehicle, so that the latter transmits various information to it.

Among this information, the main computer transmits:

- the driving direction Av, Ar of the motor vehicle 1 (forwards or backwards),

the speed V of the motor vehicle 1, in absolute value,

- the position β of the indicators 3, 4 of the motor vehicle 1 (off, on to the left or to the right),

- the angle a of the steering wheel 2 of the motor vehicle 1.

We can also expect it to transmit other information, including:

a signal for detecting a lane change in the motor vehicle 1 (which signal can be produced by means of a camera which is oriented towards the front of the vehicle and which locates the position of the vehicle with respect to the painted lane markings on the road),

the geolocated position of the motor vehicle 1 and the geolocated position of the destination entered by the driver in the navigator of the motor vehicle, and

- a signal for detecting an available parking space (which signal can be produced by means of a camera which is oriented towards the side of the vehicle).

During the third step, the processing unit 13 receives and stores in its random access memory the last image 20 acquired by the camera 11 of the vehicle.

During the fourth step, the processing unit 13 selects only part of the surface of the image stored in its RAM.

The selected part of image 20 corresponds to that which one wishes to display on the display screen 12 of the interior mirror. This selected part therefore has dimensions identical to those of this display screen 12.

As shown in FIG. 2, the height of the selected part 21 on the image 20 is intended to vary depending on the situation in which the motor vehicle 1 is located.

Thus, by way of example, the selected part 21 of the image 20 may correspond to the upper part of the image 20 (only a low band of the image then being cut) in the case where the vehicle is in motion forward or in case the vehicle is in reverse at high speed. So the driver will have a wide view of the rear environment.

On the contrary, the selected part 21 of the image 20 may correspond to the lower part of the image 20 (only a high strip of the image then being cut) in the case where the vehicle is in reverse gear at reduced speed. The driver will therefore have a view of the rear environment which is useful for making a slot.

As shown in Figure 2, the heights of the upper 22 and lower 23 borders of the selected part 21 of the image 20 may vary. They may vary suddenly (in stages), or continuously (so as to make the change of point of view more pleasant for the driver).

To select the part 21 of the image 20 which, having regard to the situation encountered, seems the most relevant to display, the processing unit 13 here takes into account the direction of travel Av, Ar of the motor vehicle 1 and the speed V of the vehicle (depending on whether it is below or above a threshold, for example 10 km / h).

To clearly distinguish the case where the motor vehicle 1 performs a simple reverse gear (without the desire to park) from the case where the driver seeks to maneuver the vehicle (in particular to park), it is possible to take other information into account.

Thus, we can provide that the lower part of image 20 is only selected if the following three conditions are met:

i) the vehicle is in reverse, ii) the speed V of the vehicle is lower than the threshold (here 10 km / h), and iii) the indicators of the vehicle are on and / or the angle a of the steering wheel 2 is greater than one predetermined threshold.

Alternatively, provision could be made for condition iii) to be met in the following cases:

- if a lane change detection signal is sent to the processing unit 13, or

- if the geolocated position of the vehicle is close to the geolocated position of the destination entered by the driver in the navigator of the motor vehicle, or

- if an available parking space is automatically detected next to the motor vehicle.

Other cases could also be considered.

In any case, once the part 21 of the image 20 has been selected, the processing unit 13 transmits it to the display screen 12 of the interior mirror.

It could be provided that it transmits this selected part 21 of the image 20 in a raw manner, or that it processes it beforehand.

Thus, the processing unit 13 could include image processing software suitable for detecting a possible obstacle on the image 20.

In the event of an obstacle detected, the processing unit 13 could then command the display on the display screen 12 of information which would be superimposed on the image 20 and which would make it possible to highlight the detected obstacle .

This information could for example be in the form of a flashing "danger sign" on the side of the part of the image displayed. It could also be in the form of a colored rectangle surrounding the detected obstacle.

The present invention is not limited to the embodiment described and shown, but the skilled person will be able to make any variant according to the invention.

Thus, one could plan to select the lower part of image 20 only if the vehicle is in reverse and one of the indicators is on.

In Figure 3, there is thus shown an alternative embodiment of the motor vehicle 1 illustrated in Figure 1. In this variant, the motor vehicle 1 differs from that of Figure 1 in that its video mirror system 10 comprises , not a single wide angle camera 11, but rather two cameras 11 A, 11B oriented towards the rear of the vehicle, in distinct directions.

In this variant, the field openings ôa, ôb of the two cameras

A, 11B are weaker than that of the camera 11 of the vehicle in FIG. 1.

The optical axes of these two cameras 11 A, 11B are here coplanar, the optical axis of a first of the cameras 11A being oriented more towards the horizon than that of the second camera 11B which is oriented more down.

An example of image 20A acquired by the first camera 11A is illustrated in FIG. 4, while an example of image 20B acquired by the second camera

11B is illustrated in FIG. 5.

So, to implement the invention, the processing unit 13 will not select an image part, but rather select one or the other of the images 20A, 20B acquired by the two cameras.

Thus, by way of example, the processing unit 13 can select the flow of images acquired by the first camera 11A when the vehicle is traveling in forward gear or when it is driving in reverse gear at a speed greater than a threshold ( for example 10 km / h). Otherwise, he can select the image stream acquired by the second camera 11 B.

Here again, the images 20A, 20B acquired by the two cameras 11 A, 11B have proportions different from those of the display screen 12 of the interior mirror. Consequently, only part of these images 20A, 20B will be displayed.

The part of each image 20A, 20B which will be displayed will be predetermined, in the sense that the positions of the high and low borders 22A, 22B, 23A, 23B will be chosen once and for all during the design of the motor vehicle 1, and they will not will not vary.

Claims (10)

1. Method for controlling a video mirror system (10) for a motor vehicle (1), comprising steps of: a) acquisition of a first parameter (Av, Ar) relating to the direction of travel of the motor vehicle (1), b) acquisition of at least one second parameter (V, α, β) relating to the commands exerted by the driver on the motor vehicle (1), c) acquisition of images (20; 20A, 20B) of the environment at the rear of the motor vehicle (1) by at least one image sensor (11; 11 A, 11 B) of the video mirror system (10), d) selection, of only part of the images (20; 20A, 20B) acquired in step c), as a function of the first and second parameters (Av, Ar, V, α, β) acquired in steps a) and b), and e) display, on a screen (12) of the video mirror system (10), of only the part of the images selected in step d). 2. The piloting method as claimed in claim 1, in which the video mirror system (10) comprising a single image sensor (20) oriented towards the rear of the motor vehicle (1), in step d) , provision is made to select a part (21) of each image (20) acquired in step c). 3. The driving method as claimed in claim 1, in which the video mirror system (10) comprising at least two image sensors (11 A, 11 B) oriented towards the rear of the motor vehicle (1), step d), provision is made to select the images (20A, 20B) acquired by only one of the two image sensors (11A, 11B). 4. Control method according to one of the preceding claims, in which, in step d), a portion of the images (20; 20A, 20B) is selected which represents either a low area of the environment seen in the near field. , or a high area of the environment seen in the far field. 5. A driving method according to one of the preceding claims, wherein said second parameter comprises at least the speed (V) of the motor vehicle (1). 6. A driving method according to one of the preceding claims, in which said second parameter comprises the position (β) of the indicators (3, 4) of the motor vehicle (1) and / or the angle (a) of the steering wheel (2 ) of the motor vehicle (1). 7. Control method according to one of the two preceding claims, in which said second parameter also includes one of the elements from the following list: - a signal for detecting a lane change in the motor vehicle (1), - a geolocated position of the motor vehicle (1), and - a signal to detect an available parking space. 8. Control method according to one of the preceding claims, in which there is provided a step of processing each image (20, 20A, 20B) acquired in order to detect an obstacle, and in which, in step e) , said obstacle is highlighted on the part of the images displayed. 9. Video mirror system (10), comprising: - an interior mirror fitted with a display screen (12), - at least one image sensor (11, 11 A, 11 B), and a processing unit (13) adapted to control the display of part of the images (20, 20A, 20B) acquired by each image sensor (11, 11 A, 11 B) on said display screen ( 12), characterized in that said processing unit (13) is adapted to implement a control method according to one of the preceding claims. 10. Motor vehicle (1) characterized in that it comprises a video mirror system (10) according to the preceding claim. 1/1 National registration number FA 833839 FR 1663202 EPO FORM 1503 12.99 (P04C14)