Method for detecting an obstacle when opening a motor-driven opening panel of a vehicle

Abstract

The invention relates to a method (100) for determining, when opening a motor-driven opening panel of a vehicle, a current value of a distance to impact between the opening panel and an obstacle, wherein the opening panel comprises a detection device arranged in an end region located on the side opposite an axis of rotation of the opening panel, and wherein the method (100) comprises, when the vehicle is stationary and the opening panel pivots about its axis of rotation between a closed position and a final open position, the steps of: - determining (108) the polar co-ordinates of the obstacle, in a reference frame centred on the detection device, wherein the polar co-ordinates comprise: - a distance between the detection device and the obstacle; and - an angle formed between the detection device and the obstacle; - depending on the polar co-ordinates, determining (109) the distance to impact between the opening panel and the obstacle.

Description

DESCRIPTION METHOD FOR DETECTING AN OBSTACLE WHEN A MOTORIZED VEHICLE OPENING ELEVATOR IS OPENING TECHNICAL FIELD OF THE INVENTION

[0001] The field of the invention is that of obstacle detection when opening a vehicle door. The invention applies more particularly, but not exclusively, to rear trunk lid type doors. TECHNOLOGICAL BACKGROUND OF THE INVENTION

[0002] The rear trunk lids of motor vehicles are commonly motorized. However, this motorization can, in certain situations, lead to collisions with the environment of the motor vehicle. It is therefore advisable to avoid, when opening, the motorized rear trunk lid impacting an obstacle located in its opening path, such as, for example, a garage ceiling, a pillar or a wall located at a distance that does not allow the rear trunk lid to fully open.

[0003] To this end, car manufacturers typically equip the rear trunk lids with an obstacle detection system capable of interacting with a rear trunk lid motor to stop its movement before it impacts the detected obstacle. Such a system includes an ultrasonic sensor disposed in an internal space of the rear trunk lid, typically between a lining and a rear skin of the rear trunk lid. The ultrasonic sensor is then capable of detecting, through the skin of the lid, the presence of obstacles.

[0004] However, due to the detection cone, the sensor may "run out of position" and fail to detect an obstacle located on the right or left edge of the vehicle's trunk lid. To overcome this drawback, car manufacturers usually install multiple sensors along the width of the trunk lid. While this solution can effectively detect obstacles, it is expensive. SUMMARY OF THE INVENTION

[0005] One objective of the invention is to propose a solution for discriminating obstacles around a vehicle door being opened which is inexpensive.

[0006] To this end, the invention thus relates, in its broadest sense, to a method for determining, when a motorized opening of a vehicle is opened, a current value of an impact distance between the opening and an obstacle, the opening comprising a detection device arranged in an end region of the opening, said end region being located on the side opposite an axis of rotation of the opening, the method comprising, when the vehicle is stationary and the opening pivots around its axis of rotation between a closed position and a final open position, the steps of: Using the detection device, transmit a pulse-modulated radiofrequency signal, called the transmitted signal, and receive a radiofrequency signal, called the received signal, originating from the reflection of the transmitted signal on said obstacle; Determine a Doppler frequency of the received signal; Receive a current value of rotational angular velocity (w=d0 / dt) or angular position (0(t)) from the detection device (either value can be transmitted, the two being linked by a time derivative / integral relationship); Determine polar coordinates of the obstacle in a reference frame centered on the detection device, said polar coordinates comprising: A distance between the detection device and the obstacle, and An angle formed between the detection device and the obstacle, depending on the current value of the angular rotation speed (w=d0 / dt) of the detection device, the angular position (0(t)) of the detection device and the Doppler frequency, Based on the polar coordinates, determine the impact distance between the opening and the obstacle.

[0007] This implementation allows, with a single detection device, to discriminate between obstacles placed opposite and to the side of the detection device. The cost of implementing this solution is therefore low.

[0008] By using the method according to the invention, an impact distance between the opening and the obstacle is determined, and not a distance between the detection device and the obstacle. This avoids considering that an obstacle located on one side of the detection device is very far from the opening.

[0009] In addition to the characteristics which have just been mentioned in the preceding paragraph, the method according to the invention may have one or more additional characteristics among the following, considered individually or according to all technically possible combinations.

[0010] According to a non-limiting implementation of the invention, the determination of an angle formed between the detection device and the obstacle, comprises, for a position of the vehicle with its wheels resting on horizontal ground: When the opening is in a first phase of its opening movement, between its closed position and an intermediate position, the determination of an angle formed, according to a projection in a horizontal plane, between an axis connecting said detection device to said obstacle and a longitudinal vertical plane of the vehicle passing through said detection device, When the opening is in a second phase of its opening movement, between said intermediate position and its final opening position, the determination of an angle formed, according to a projection in a transverse vertical plane passing through said detection device, between an axis connecting said detection device to said obstacle and the longitudinal vertical plane.

[0011] According to a non-limiting implementation of the invention, for a position of the vehicle with its wheels resting on horizontal ground and when the opening is in the first phase of its opening movement, the impact distance between the opening and the obstacle is determined via the following formula: D28=cos ai * D48 With, Cos ai = (Doppler frequency of the received signal * speed in vacuum of the transmitted signal / (2 * carrier frequency of the transmitted signal) * Vx), Vx = (radius between the axis of rotation of the opening and the detection device * angular speed of rotation of said axis of rotation * cos 0 (we understand that the angular speed of rotation of said axis of rotation corresponds to the speed of rotation of the detection device), 0 = opening angle of said opening relative to the transverse vertical plane of the vehicle (we understand that this angle corresponds to the angular position of the detection device).

[0012] According to a non-limiting implementation of the invention, for a position of the vehicle with its wheels resting on horizontal ground and when the opening is in the second phase of its opening movement, the impact distance between the opening and the obstacle is determined via the following formula: D28 = cos «2 * D48 With, Cos «2 = (Doppler frequency of the received signal * speed in vacuum of the transmitted signal / (2* carrier frequency of the transmitted signal) * Vy), Vy = (radius between the axis of rotation of the opening and the detection device * angular speed of rotation of said axis of rotation) * sin 0, 0 = opening angle of said opening relative to the transverse vertical plane of the vehicle.

[0013] According to a non-limiting implementation of the invention, the method comprises a step of generating a command to stop the opening of the opening when the impact distance is less than or equal to a threshold impact distance.

[0014] According to a non-limiting implementation of the invention, the opening is in the intermediate position, when the radius between the axis of rotation of the opening and the detection device forms an angle 0 between 70° and 110° relative to the transverse vertical plane.

[0015] According to a non-limiting implementation of the invention, the pulse-modulated radiofrequency signal is of the ultra-wideband type.

[0016] According to a non-limiting implementation of the invention, the method comprises a step of detecting, using the signals emitted and received by the detection device, a command to open the opening, said opening command being formed by a movement of a user located in a coverage area of ​​said detection device.

[0017] According to a non-limiting implementation of the invention, the method comprises the steps of: Detect, via the detection device and using two-way radio frequency communication with a user badge, the presence, in a coverage area of ​​said detection device, of a user authorized to access the vehicle; Transmit an unlocking command to a device for locking and unlocking the opening, when such a presence is detected.

[0018] The invention also relates to a computer program product comprising instructions which, when the program is executed by a computer, cause the latter to implement the steps of the method according to any one of the preceding implementations.

[0019] The invention further relates to a motor vehicle comprising: A motorized opening, A device for driving the rotation of said opening element capable of controlling the opening and closing of said opening element, and A detection device capable of emitting a pulse-modulated radiofrequency signal, called the emitted signal, and receiving a radiofrequency signal, called the received signal, originating from the reflection of the emitted signal on an obstacle, said detection device being arranged in an end region of said opening, said end region being located on the side opposite an axis of rotation of said opening, said detection device being capable of executing the steps of the method according to any one of the aforementioned implementations.

[0020] The invention and its various applications will be better understood by reading the following description and examining the accompanying figures. BRIEF DESCRIPTION OF THE FIGURES

[0021] The figures are presented for information purposes only and in no way limit the invention.

[0022] [Fig. 1] schematically illustrates a three-dimensional view of a vehicle according to a non-limiting aspect of the invention.

[0023] [Fig. 2] schematically illustrates a side view of a vehicle according to a non-limiting aspect of the invention, the vehicle comprising a rear trunk flap positioned in a first position.

[0024] [Fig. 3] shows, schematically, the steps of a method according to a non-limiting aspect of the invention.

[0025] [Fig. 4] schematically illustrates a top view of the vehicle according to the invention illustrated in Figure 2.

[0026] [Fig. 5] schematically illustrates a side view of the vehicle according to the invention illustrated in Figure 2, the rear trunk flap being positioned in a second position.

[0027] [Fig. 6] schematically illustrates a rear view of the vehicle according to the invention illustrated in Figure 2, the rear trunk flap being positioned in the second position. DETAILED DESCRIPTION

[0028] Unless otherwise specified, the same element appearing in different figures has a single reference.

[0029] Figure 1 schematically illustrates a motor vehicle 1 conforming to a non-limiting implementation of the invention.

[0030] A longitudinal vertical plane P1, a transverse vertical plane P2 and a horizontal plane P3 of vehicle 1 according to the terrestrial reference frame are represented.

[0031] As illustrated in Figure 2, the vehicle 1 has a motorized opening 2 formed by a rear trunk flap.

[0032] The vehicle 1 further comprises a rotation drive device 3 for the opening 2, the rotation drive device 3 being capable of controlling the opening and closing of the opening 2. The rotation drive device 3 is, for example, formed by an electric motor and means for controlling said electric motor.

[0033] The vehicle 1 also comprises a detection device 4 capable of emitting a pulse-modulated radiofrequency signal, called the emitted signal, and receiving a radiofrequency signal, called the received signal, originating from the reflection of the emitted signal on an obstacle. The detection device 4 is, for example, formed by a sensor capable of emitting and receiving a radiofrequency signal and means for controlling said sensor.

[0034] A pulse-modulated radio frequency signal (as opposed to a continuous signal) has so-called radio frequency pulses. In other words, the radio frequency signal has a pulse-type modulation. Using this type of signal makes it possible, in particular, to determine the distance between a target and the sensor.

[0035] According to a non-limiting implementation, the emitted pulse-modulated radiofrequency signal is a signal modulated according to the modulation technique known as "UWB", for "Ultra Wide Band". This modulation technique is based on the transmission of pulses of very short duration, preferably less than one nanosecond, and over a wide frequency spectrum.

[0036] The detection device 4 is arranged in an end region 5 of the opening 2. The end region 5 is arranged on the side opposite to an axis of rotation 6 of the opening 2. More particularly, this end region 5 is located in a region close to the opening button of the opening 2 or covers the opening button of the opening 2.

[0037] According to this non-limiting embodiment, the vehicle 1 also comprises a locking and unlocking device 7 for the opening 2.

[0038] The detection device 4, the rotation drive device 3 and the locking and unlocking device 7 are, together, capable of executing, when the vehicle 1 is stationary, the steps of the method 100 presented below.

[0039] The method 100 executes, using the detection device 4, a step of emitting 101 a pulse-modulated radiofrequency signal, called the emitted signal, and receiving 102 a radiofrequency signal, called the received signal, originating from the reflection on an obstacle 8 a , 8b of the transmitted signal.

[0040] Obstacle 8 ais formed, in this example, by a post. As can be seen in Figure 4 forming a top view of the vehicle 1 illustrated in Figure 2, the post 8a is arranged on the right side of the vehicle 1. For reasons of clarity, the obstacle 8b is not shown in this Figure 4. Furthermore, the obstacle 8b is formed by a beam. Similarly, as can be seen in Figure 6 forming a rear view of the vehicle 1, the beam 8b is arranged on the right side of the vehicle 1. For reasons of clarity, the obstacle 8 a is not shown in this figure 6.

[0041] The method 100 comprises the steps of detecting 103, via the detection device 4 and using two-way radio frequency communication with a user badge, the presence, in a coverage area of ​​the detection device 4, of a user authorized to access the vehicle 1, then of transmitting 104 an unlocking command to the locking and unlocking device 7 of the opening 2, when the presence of the user authorized to access the vehicle 1 is detected.

[0042] In other words, when a user badge of the vehicle 1 is located in a coverage area of ​​the detection device 4, the latter is able to detect the presence of this badge. The detection of the presence of this badge in the coverage area of ​​the detection device 4 then forms a command to unlock the opening 2 of the vehicle 1. The unlocking command is then transmitted to the locking and unlocking device 7 of the opening 2, which then controls the unlocking of the opening 2.

[0043] According to a non-limiting implementation, the method 100 comprises a step of detecting 105, using radiofrequency signals emitted and received by the detection device 4, a command to open the opening 2. The opening command is formed by a movement of a user located in a coverage area of ​​the detection device 4. The opening command can be formed by a foot or hand movement of a user located in the coverage area of ​​the detection device 4.

[0044] The method 100 comprises a step of determining 106, via the detection device 4, a Doppler frequency of the received signal.

[0045] The method 100 also comprises a step of receiving 107 a current value of angular rotation speed of the detection device 4 or a current value of angular position of the detection device 4. This current value of angular rotation speed or angular position of the detection device 4 can be determined via control means (not illustrated) of the vehicle 1, then transmitted to the detection device 4.

[0046] Then, the method 100 executes a step of determining 108 polar coordinates of the obstacle 8 a, 8b in a frame of reference centered on the detection device 4.

[0047] When the opening leaf 2 is rotated, it moves from a closed position to an intermediate position as shown in Figure 5. Then, as it continues to open, the opening leaf 2 moves from the intermediate position to a final open position.

[0048] According to a non-limiting implementation, the opening 2 is in the intermediate position, when a ray R connecting the axis of rotation 6 of the opening 2 and the detection device 4 forms an angle 0 between 70° and 110° relative to the transverse vertical plane P2.

[0049] Polar coordinates include: A distance D48 between the detection device 4 and the obstacle 8 a , 8b, and An angle ai, oc2 formed between the detection device 4 and the obstacle 8 a, 8b depending on the current value of angular rotational speed of the detection device 4 or the current value of angular position of the detection device 4 and the Doppler frequency.

[0050] The distance between the detection device 4 and the obstacle 8 a , 8b is formed by a distance D48 between the detection device 4 and the obstacle 8 a , 8b determined by the time of flight of the wave.

[0051] As illustrated in Figure 4, determining the angle formed between the detection device 4 and the obstacle 8 a includes, for a position of the vehicle 1 with its wheels resting on horizontal ground and when the opening 2 is in a first phase of its opening movement, between its closed position and an intermediate position, the determination of an angle ai formed, according to a projection in the horizontal plane P3, between an axis A1 connecting the detection device 4 to the obstacle 8a and the longitudinal vertical plane P1 of the vehicle 1 passing through the detection device 4. More particularly, the axis A1 connects a reference point P4 of the detection device 4 to the obstacle 8 a . The A1 axis is similar to the distance Ü48.

[0052] As illustrated in Figure 6, the determination of the angle formed between the detection device 4 and the obstacle 8b comprises, for a position of the vehicle 1 with its wheels resting on horizontal ground and when the opening 2 is in a second phase of its opening movement, between the intermediate position and its final opening position, the determination of an angle oc2 formed, according to a projection in the transverse vertical plane P2 passing through the detection device 4, between the axis A2 connecting the detection device 4 to the obstacle 8b and the longitudinal vertical plane P1. The axis A2 is similar to the distance D48.

[0053] Depending on the determined polar coordinates, the method 100 comprises a step 109 of determining the impact distance D28 between the opening 2 and the obstacle 8 a , 8 b .

[0054] It should be noted that the impact distance D28 between the opening 2 and the obstacle 8 a , 8b is shorter than the distance D48 between the detection device 4 and the obstacle 8 a , 8b. This difference is due to the angular offset of obstacle 8 a , 8b with respect to the detection device 4.

[0055] In a non-limiting manner, for a position of the vehicle 1 with its wheels resting on horizontal ground and when the opening is in the first phase of its opening movement, the impact distance D28 between the opening 2 and the obstacle 8 a is determined using the following formula: D28=cos oc1 * D48 With, Cos al = (Doppler frequency of the signal * speed in vacuum of the emitted signal / (2* carrier frequency of the emitted signal) * Vx) Vx = (radius R between the axis of rotation 6 of the opening 2 and the detection device 4 * angular speed of rotation of the axis of rotation 6 * cos 0 0 = opening angle of the opening 2 relative to the transverse vertical plane P2 of the vehicle.

[0056] As illustrated in Figure 5, if the post 8a is sufficiently far from the opening 2, the rotation of the latter brings it to the intermediate position, for example parallel to the horizontal plane P3. In this case, the obstacle is no longer formed by the post 8a but by the beam 8b.

[0057] In a non-limiting manner, for a position of the vehicle 1 with its wheels resting on horizontal ground and when the opening is in the second phase of its opening movement, the impact distance D28 between the opening 2 and the obstacle 8b is determined via the following formula: D28=cos oc2 * D48 With, Cos oc2 = (Doppler frequency of the received signal * speed in vacuum of the transmitted signal / (2* carrier frequency of the transmitted signal) * Vy) Vy = (radius R between the rotation axis 6 of the opening 2 and the detection device 4 * angular speed of rotation of the rotation axis 6) * sin 0 0 = opening angle of the opening 2 relative to the transverse vertical plane P2 of the vehicle.

[0058] The method 100 further comprises a step of generating 110 a command to stop the opening of the opening 2 when the impact distance D28 is less than or equal to a threshold impact distance. This threshold impact distance may for example be between 1 cm and 10 cm.

[0059] It should be noted that the examples of implementation of the method according to the invention cited above relate to an opening of the vehicle rear trunk flap type, but it is understood that this method applies to any type of motorized opening of vehicle, for example a vehicle front trunk lid or a vehicle door.

Claims

CLAIMS

1. Method (100) for determining, when opening a motorized opening (2) of a vehicle (1), a current value of an impact distance (D28) between said opening (2) and an obstacle (8 a , 8b), said opening (2) comprising a detection device (4) arranged in an end region (5) of said opening (2), said end region (5) being located on the side opposite an axis of rotation (6) of said opening (2), said method (100) comprising, when said vehicle (1) is stationary and said opening (2) pivots around its axis of rotation (6) between a closed position and a final open position, the steps of: - Using said detection device (4), transmit (101) a pulse-modulated radiofrequency signal, called the transmitted signal, and receive (102) a radiofrequency signal, called the received signal, coming from the reflection on said obstacle (8 a , 8b) of the emitted signal - Determine (106) a Doppler frequency of said received signal; - Receive (107) a current value of angular rotation speed or angular position of said detection device (4); - Determine (108) the polar coordinates of said obstacle (8 a , 8b), in a reference frame centered on said detection device (4), said polar coordinates comprising: o A distance (D48) between said detection device (4) and said obstacle (8 a , 8b), and o An angle formed between said detection device (4) and said obstacle (8 a , 8b), function of the current value of angular rotation speed of the detection device (4), of the current value of angular position of the detection device (4) and of said Doppler frequency, - Based on said polar coordinates, determine (109) the impact distance (D28) between said opening (2) and said obstacle (8 a , 8b).

2. Method (100) according to claim 1, characterized in that the determination of an angle formed between the detection device (4) and the obstacle (8 a , 8b), includes, for a position of the vehicle (1) with its wheels resting on horizontal ground: o When the opening (2) is in a first phase of its opening movement, between its closed position and an intermediate position, the determination of an angle (ai) formed, according to a projection in a horizontal plane (P3), between an axis (A1) connecting said detection device (4) to said obstacle (8 a) and a longitudinal vertical plane (P1) of the vehicle (1) passing through said detection device (4), o When the opening (2) is in a second phase of its opening movement, between said intermediate position and its final opening position, the determination of an angle (“2) formed, according to a projection in a transverse vertical plane (P2) passing through said detection device (4), between an axis (A2) connecting said detection device (4) to said obstacle (8b) and the longitudinal vertical plane (P1).

3. Method (100) according to claim 2, characterized in that, for a position of the vehicle (1) with its wheels resting on horizontal ground and when the opening (2) is in the first phase of its opening movement, the impact distance (D28) between the opening (2) and the obstacle (8 a ) is determined using the following formula: D28=cos ai * D48 With, - Cos ai = (Doppler frequency of the received signal * speed in vacuum of the transmitted signal / (2* carrier frequency of the transmitted signal) * Vx) - Vx = (radius (R) between the axis of rotation (6) of the opening (2) and the detection device (4) * angular speed of rotation of said axis of rotation (6) * cos 0 - 0 = opening angle of said opening (2) relative to the transverse vertical plane (P2) of the vehicle (1).

4. Method (100) according to claim 2 or 3, characterized in that, for a position of the vehicle (1) with its wheels resting on horizontal ground and when the opening (2) is in the second phase of its opening movement, the impact distance (D28) between the opening (2) and the obstacle (8b) is determined using the following formula: D28=cos «2 * D48 With, - Cos «2 = (Doppler frequency of the received signal * speed in vacuum of the transmitted signal / (2* carrier frequency of the transmitted signal) * Vy) - Vy = (radius (R) between the axis of rotation (6) of the opening (2) and the detection device (4) * angular speed of rotation of said axis of rotation (6)) * sin 0 - 0 = opening angle of said opening (2) relative to the transverse vertical plane (P2) of the vehicle (1). [Claim s] Method (100) according to any one of the preceding claims, characterized in that it comprises a step of generating (110) a command to stop the opening of the opening (2) when the impact distance (D28) is less than or equal to a threshold impact distance. [Claim s] Method (100) according to any one of the preceding claims, characterized in that the opening (2) is in the intermediate position, when the radius (R) between the axis of rotation (6) of the opening (2) and the detection device (4) forms an angle 0 between 70° and 110° relative to the transverse vertical plane (P2).

7. Method (100) according to any one of the preceding claims, characterized in that the pulse-modulated radiofrequency signal is of the ultra-wideband type. [Claim s] Method (100) according to any one of the preceding claims, characterized in that it comprises a step of detecting (105), using the signals emitted and received by the detection device (4), a command to open the opening (2), said opening command being formed by a movement of a user located in a coverage area of said detection device (4).

9. Method (100) according to any one of the preceding claims, characterized in that it comprises the steps of: - Detect (103), via the detection device (4) and using two-way radio frequency communication with a user badge, the presence, in a coverage area of said detection device (4), of a user authorized to access the vehicle (1); - Transmit (104) an unlocking command to a locking and unlocking device (7) of the opening (2), when such a presence is detected.

10. Motor vehicle (1) comprising: - A motorized opening (2), - A rotation drive device (3) for said opening (2) capable of controlling the opening and closing of said opening (2), and - A detection device (4) capable of emitting a pulse-modulated radiofrequency signal, called the emitted signal, and receiving a radiofrequency signal, called the received signal, originating from the reflection on an obstacle (8 a, 8b) of the emitted signal, said detection device (4) being arranged in an end region (5) of said opening (2), said end region (5) being located on the side opposite to an axis of rotation (6) of said opening (2), said detection device (4) being capable of carrying out the steps of the method (100) according to any one of claims 1 to 9.

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