Automatic control method and control system for high and low beam headlights, and vehicle having the system

Abstract

The present invention relates to the field of intelligent driving technology, and particularly to an automatic control method for high and low beam lights, a control system, and a vehicle having the system. The control method includes: acquiring driving image information; processing the image information to identify a target object and calculating relevant data of the target object to obtain the spatial position and motion trajectory of the target object; the relevant data of the target object includes category, speed, direction, distance between the self-vehicle and the target object, and position in the image; acquiring the current state of the high beam light and the blinding coverage space area of the high beam light, and judging whether the target object is in the blinding coverage space area of the high beam light according to the motion trajectory and spatial position of the target object, so as to realize automatic switching of the high and low beam lights. The high and low beam light switching control of the present invention has high accuracy, can adapt to more road conditions, can meet the switching requirements of the high and low beam lights, and improves the driving safety.

Description

Technical Field

[0001] The present invention relates to the technical field of intelligent driving, and particularly to an automatic control method for high and low beam lights, a control system, and a vehicle equipped with the system. Background Art

[0002] When driving at night, lights are the "eyes" of a vehicle. According to traffic regulations, when a vehicle is driving at night, within the light interaction with oncoming traffic participants, it is stipulated that high beam lights cannot be used within 150 meters. Additionally, the standard numbered "GB / 4785 - 2019" stipulates that when a high beam light is turned on and a vehicle driving in the oncoming or same direction is detected, the high beam light should be automatically turned off. However, in actual driving, due to conditions such as the driver's driving level, the variable height of the high beam light, and night visibility, it is very difficult to implement this standard.

[0003] Currently, through an adaptive high and low beam adjustment system that integrates functional hardware sensors and software, that is, when a vehicle turns on its headlights at night, the vehicle's headlights use sensors (usually a camera located inside the front windshield) to judge the situation of oncoming vehicles on the road and automatically switch between high and low beam lights, enabling the driver to focus more on driving. The prior art only uses the judgment of the distance from oncoming vehicles as the basis for switching high and low beam lights. However, the distances and positions at which the high beam lights of different vehicles cause temporary blindness to the human eye are different. For example, the higher the height of the high beam light, the farther the high beam coverage range. If only the distance from oncoming vehicles is used as the switching requirement, there is a risk of temporary blindness to oncoming vehicles before the high and low beam lights are switched. Another example is that when the vehicle is driving in an extra-wide lane, the target and the vehicle are on both sides of the road, with a large lateral distance. The vehicle's high beam light no longer covers the target, and at this time, there is no need to switch between high and low beam lights. However, if the distance from oncoming vehicles is used as the switching requirement, it will reduce the visibility of the vehicle's field of view and affect the driving safety of the vehicle. Therefore, relying solely on a distance indicator to control the switching of high and low beam lights has low accuracy and cannot guarantee driving safety.

[0004] In addition, the switching of high and low beam lights cannot be performed before the high beam light causes harm to oncoming targets, and this also includes the prediction of the moment when the space area blinded by the vehicle's high beam light is about to move away from the target. Therefore, it is not possible to appropriately switch from low beam lights to high beam lights in a timely manner, increasing the probability of accidents. Summary of the Invention

[0005] The technical problem to be solved by the present invention is: to solve the technical problems in the prior art that the switching control accuracy of high and low beam lights is low, unable to meet the switching requirements of high and low beam lights, and driving safety cannot be guaranteed. The present invention provides an automatic control method for high and low beam lights, with high switching control accuracy of high and low beam lights, capable of meeting the switching requirements of high and low beam lights, and improving driving safety.

[0006] The technical solution adopted by the present invention to solve its technical problems is: an automatic control method for high and low beam headlights, including:

[0007] Step S1: Obtain driving image information. Obtaining the image information includes collecting original image data through a camera and then processing the original image data to generate recognition image information;

[0008] Step S2: Process the image information, identify the target object, and calculate relevant data of the target object to obtain the spatial position and movement trajectory of the target object;

[0009] The relevant data of the target object includes category, speed, direction, the distance between the self-vehicle and the target object, and the position in the image;

[0010] Step S3: Obtain the current state of the high beam headlights and the blinding coverage spatial area of the high beam headlights. According to the movement trajectory of the target object and the spatial position of the target object, determine whether the target object is in the blinding coverage spatial area of the high beam headlights, and realize automatic switching of the high and low beam headlights.

[0011] Further, specifically, in the step S3:

[0012] If the current state of the high beam headlights is on and the target object is in the blinding coverage spatial area of the high beam headlights, then calculate the first time for the high beam headlights to cover the target object according to the data of the target object, and automatically control the high beam headlights to turn off;

[0013] If the current state of the high beam headlights is off and the target object is far from the blinding coverage spatial area of the high beam headlights, then calculate the second time for the high beam headlights to move away from the target object according to the data of the target object, and automatically control the high beam headlights to turn on.

[0014] Further, specifically, in the step S2, it specifically includes the following steps:

[0015] S21: Input the image information into a CNN network model for detection to obtain the category of at least one target object and the position of the target object in the image;

[0016] S22: According to the position of the target object in the image, calculate the spatial position of the target object in the world coordinate system through the internal and external parameters of the camera;

[0017] S23: Calculate the distance between the self-vehicle and the target object and the speed of the target object according to the vehicle speed of the self-vehicle and the position change of the target object between frames, and judge the direction of the target object relative to the self-vehicle.

[0018] Further, specifically, the step S22 includes the following steps:

[0019] Calculate the rectangular box of the target object in the image through the CNN network model. Let the angle between the optical axis of the camera and the ground in the vertical direction be θ y , and the angle between the optical axis of the camera and the ego-vehicle in the horizontal direction be θ x . The distance calculation formula between the ego-vehicle and the target object is as follows:

[0020]

[0021] where h is the installation height of the camera, f is the focal length of the camera, x is the horizontal distance between the projection point of the rectangular box in the image and the optical axis point, y is the vertical distance between the optical axis point in the image and the lower edge line of the rectangular box, and LA and LB are the horizontal distance and vertical distance between the target object and the ego-vehicle respectively;

[0022] In step S23, the relative position of the target object from the ego-vehicle at time t is calculated by formula (1) as (LA t , LB t ), and the relative position of the target object from the ego-vehicle at time t + a is (LA t+a + v x dt, LB t+a + v y dt). The motion straight line of the target object from time t to time t + a is:

[0023]

[0024] where v x and v y are the longitudinal and lateral speeds of the ego-vehicle respectively;

[0025] The speed calculation formula of the target object is:

[0026]

[0027] Furthermore, specifically, in step S23, determining the direction of the target object relative to the ego-vehicle includes the following steps:

[0028] Take the difference between LA t+a + v x dt and LA t , and judge the direction of the target object relative to the ego-vehicle according to the calculation result:

[0029] If the calculation result is greater than zero, the target object and the ego-vehicle are running in the same direction;

[0030] If the calculated result is equal to zero, the target object is in a stationary state relative to the host vehicle or perpendicular to the direction of the host vehicle;

[0031] If the calculated result is less than zero, the target object is moving in the opposite direction to the host vehicle.

[0032] Further, specifically, in step S3, according to formula (2), the speed of the target object, and the speed of the host vehicle, calculate the first time when the high beam covers the target object and the second time when the high beam moves away from the target object.

[0033] Further, specifically, after automatically controlling the high beam to turn off, also track and predict the trajectory of the target object. When the target object is not in the blinding coverage area of the high beam, automatically turn on the high beam.

[0034] Further, specifically, in step S2, also detect whether the target object has a rearview mirror according to the image information, and whether the reflective surface of the rearview mirror is facing the host vehicle.

[0035] An automatic high and low beam control system, the control system includes:

[0036] A camera, which collects driving image information;

[0037] A processor, which is used to execute the automatic high and low beam control method as described above when executed.

[0038] A vehicle, on which the above-mentioned control system is installed.

[0039] The beneficial effects of the present invention are as follows

[0040] (1) Process the image information captured by the camera, calculate the spatial position of the target object, and realize the automatic switching of the high and low beams based on the spatial position of the target object. There is no need to additionally increase sensors. Compared with the prior art that uses the distance from the oncoming vehicle as the switching basis, the accuracy of the present invention is higher, so that the adjustment of the high and low beams during driving is more timely and accurate, improving the driving safety.

[0041] (2) Control the high and low beams through the first time when the high beam covers the target object and the second time when the high beam moves away from the target object, further improving the driving safety. Brief Description of the Drawings

[0042] The present invention will be further described below with reference to the drawings and embodiments.

[0043] Figure 1 It is a flowchart of the control method of Embodiment 1 of the present invention.

[0044] Figure 2 It is the specific flowchart of step S2 in the first embodiment of the present invention.

[0045] Figure 3 It is the detailed flowchart of the control method in the first embodiment of the present invention.

[0046] Figure 4 It is the schematic diagram of the target object in the coordinate system in the first embodiment of the present invention.

[0047] Figure 5 It is the schematic diagram of the image information of the target object in the first embodiment of the present invention.

[0048] Figure 6 It is the schematic diagram of the glare range of the high beam in the first embodiment of the present invention

[0049] Figure 7 It is the schematic diagram of the interaction between the host vehicle and the target object in the first embodiment of the present invention.

[0050] Figure 8 It is the schematic diagram of the structure of the control system in the second embodiment of the present invention.

[0051] In the figure, 100 is the camera; 200 is the processor. Detailed implementation manners

[0052] Now, the present invention will be further described in detail with reference to the accompanying drawings. These drawings are all simplified schematic diagrams, only illustrating the basic structure of the present invention in a schematic manner, so they only show the components related to the present invention.

[0053] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. In addition, the features defined as "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "a plurality" is two or more.

[0054] In the description of the present invention, it should be noted that, unless otherwise clearly specified and defined, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be a direct connection or an indirect connection through an intermediate medium, and it may be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0055] Embodiment 1

[0056] As Figure 1 shown, it is Embodiment 1 of the present invention, an automatic control method for high and low beam lights, including:

[0057] Step S1: Obtain driving image information. Obtaining the image information includes processing the original image data collected by a camera to generate recognition image information.

[0058] Step S2: Process the image information, identify the target object, and calculate the relevant data of the target object to obtain the spatial position and movement trajectory of the target object; the relevant data of the target object includes the category, speed, direction, distance between the vehicle itself and the target object, and the position in the image.

[0059] Step S3: Obtain the current state of the high beam light and the blinding coverage spatial area of the high beam light. According to the movement trajectory and spatial position of the target object, determine whether the target object is in the blinding coverage spatial area of the high beam light to achieve automatic switching of the high and low beam lights.

[0060] Specifically, if the current state of the high beam light is on and the target object is in the blinding coverage spatial area of the high beam light, then calculate the first time when the high beam light covers the target object according to the data of the target object, and automatically control the high beam light to turn off; if the current state of the high beam light is off and the target object is away from the blinding coverage spatial area of the high beam light, then calculate the second time when the high beam light is away from the target object according to the data of the target object, and automatically control the high beam light to turn on.

[0061] In the embodiment of the present invention, as Figure 2 shown, in step S2, it specifically includes the following steps:

[0062] S21: Input the image information into a CNN (Convolutional Neural Networks) network model for detection to obtain the category of at least one target object and the position of the target object in the image; wherein, the category of the target object is at least one of a motor vehicle, a pedestrian, a cycling vehicle, an agricultural vehicle, or other vehicles.

[0063] S22: Calculate the spatial position of the target object in the world coordinate system based on the position of the target object in the image and the internal and external parameters of the camera. Specifically, the internal and external parameters of the camera are obtained through camera calibration. The spatial position of the target object in the world coordinate system is obtained according to the principle of pinhole imaging and the internal and external parameters of the camera, and the position mapping of the target object in the world coordinate system on the image is obtained through the transformation matrix.

[0064] S23: Calculate the distance between the host vehicle and the target object and the speed of the target object based on the speed of the host vehicle and the position change of the target object between frames, and determine the direction of the target object relative to the host vehicle.

[0065] In the embodiment of the present invention, step S22 includes the following steps:

[0066] As Figures 4-5 shown, calculate the rectangular frame of the target object in the image through the CNN network model. Let the angle between the optical axis of the camera and the ground in the vertical direction be θ y , and the angle between the optical axis of the camera and the host vehicle in the horizontal direction be θ x . The distance calculation formula between the host vehicle and the target object is:

[0067]

[0068] where h is the installation height of the camera, f is the focal length of the camera, x is the horizontal distance between the projection point of the rectangular frame in the image and the optical axis point, y is the vertical distance between the optical axis point in the image and the lower edge line of the rectangular frame, and LA and LB are the lateral distance and longitudinal distance between the target object and the host vehicle, respectively;

[0069] Establish a three-dimensional rectangular coordinate system. As Figure 4 shown, obtain the projection of the optical axis line on the XY plane and the angle projected onto the XZ plane. This angle is the angle θ between the optical axis of the camera and the host vehicle in the horizontal direction x , and obtain the angle between the projection of the optical axis line on the XZ plane and the XY plane. This angle is the angle θ between the optical axis of the camera and the ground in the vertical direction y .

[0070] In step S23, calculate the relative position of the target object from the host vehicle at time t as (LA t , LB t ) through formula (1). The relative position of the target object from the host vehicle at time t + a is (LA t+a + v x dt, LB t+a + v y dt). As Figure 7 shown, the motion straight line of the target object from time t to time t + a is:

[0071]

[0072] where v x and v y are the longitudinal and lateral speeds of the host vehicle respectively;

[0073] The speed calculation formula of the target object is:

[0074]

[0075] Compared with the prior art where the distance to the target object is calculated by identifying feature points in the image information, in the embodiments of the present invention, it is not necessary to rely on identifying other feature points in the image to calculate the coordinate position of the target object in the world coordinate system and the distance between the host vehicle and the target object, avoiding the influence of the road environment, which may lead to the inability to accurately identify the feature points in the image information and affect the accuracy of the calculation results. At the same time, by combining the glare areas of the high beam lights with different high beam light heights, road conditions and other factors to calculate the switching moment of the high and low beam lights, a practical and scientific basis is provided for the triggering condition of the high and low beam light switching. Through the calculations of formulas (1), (2), and (3), the accuracy of the calculation results is improved, thereby improving the accuracy of the high and low beam light switching, further improving the driving safety, and being not affected by the night environment, with a wider range of use and high universality.

[0076] It should be noted that, in order to further improve the accuracy of the calculation results, Kalman filtering is also performed on the calculated spatial position of the target object and the speed of the target object to obtain a more accurate spatial position of the target object and the speed of the target object.

[0077] In the embodiments of the present invention, determining the direction of the target object relative to the host vehicle includes the following steps: Subtracting LA t+a +v x dt from LA t and judging the direction of the target object relative to the host vehicle according to the calculation result, where the host vehicle direction is the current moving direction of the host vehicle:

[0078] If the calculation result is greater than zero, the target object and the host vehicle are moving in the same direction;

[0079] If the calculation result is equal to zero, the target object is in a stationary state relative to the host vehicle or perpendicular to the direction of the host vehicle;

[0080] If the calculation result is less than zero, the target object and the host vehicle are moving in the opposite direction.

[0081] In the embodiments of the present invention, according to formulas (2), the speed of the target object, and the speed of the host vehicle, the first time when the high beam light covers the target object and the second time when the high beam light moves away from the target object are calculated.

[0082] It should be noted that the relevant data of the target object also includes a first threshold and a second threshold preset according to the target object category. The first threshold is used to turn off the high beam in advance, and the second threshold is used to turn on the high beam later.

[0083] In the embodiment of the present invention, the automatic control of turning off the high beam specifically includes the following steps: If the current state of the high beam is on, and the target object is in the blinding coverage space area of the high beam, determine whether the first time is within the first threshold (the first time is less than the first threshold). If the first time is within the first threshold, turn off the high beam; otherwise, continue to keep the high beam on. The automatic control of turning on the high beam specifically includes the following steps: If the current state of the high beam is off, and the target object is away from the blinding coverage space area of the high beam, automatically control the turning on of the high beam within the time of the second time plus the second threshold; if the target object is in the blinding coverage space area of the high beam, continue to keep the high beam off. Compared with the prior art in which the preset distance is used as the switching condition for the high and low beams, in the embodiment of the present invention, the high and low beams are switched in a timely manner through the first time when the high beam covers the target object and the second time when the high beam is away from the target object, with higher safety.

[0084] In the embodiment of the present invention, after automatically controlling the high beam to turn off, the target object is also tracked and its trajectory is predicted. When the target object is not in the blinding coverage space area of the high beam, the high beam is automatically turned on. Specifically, the target object is tracked by obtaining the image information of the next moment, and then the trajectory of the target object is predicted by identifying the moving straight line of the target object and the speed of the target object, and it is detected whether the target object is in the blinding coverage space area of the high beam, so as to realize the automatic control of the high and low beams.

[0085] As Figure 3 shown, in step S2, it is also detected according to the image information whether the target object has a rearview mirror, and whether the reflective surface of the rearview mirror is facing the self-vehicle. When driving at night, if the vehicle ahead is a vehicle traveling in the same direction, the high beam is also turned on to dazzle the driver through the rearview mirror. By identifying whether the target object is a vehicle traveling in the same direction or an object vehicle, it is convenient for the self-vehicle to track the target, further improving the driving safety.

[0086] In the embodiment of the present invention, the acquisition of the blinding coverage space area of the high beam includes the following steps:

[0087] Obtain driving environment information, which includes at least one or a combination of multiple types of road information (sharp turns, slopes, arch bridges, sidewalks, obstacles ahead, etc.), climate information (rain, snow, fog, etc.), and driving information (turning, going straight, etc.);

[0088] According to the driving environment information, calibrate the three-dimensional space according to the coverage range of the height of the self-vehicle's high beam. The top view and side view of the calibrated range are as Figure 6As shown, within the calibrated three-dimensional space, the light intensity tester performs light intensity glare calibration, calculates and saves the blinding coverage space area of the high beam. The storage format of the blinding coverage space area of the high beam is as follows:

[0089] [[[0010050…0]…[0080100…0]][[0010050…0]…[0080100…0]]…];

[0090] Among them, in the storage format, it is the light intensity value of the corresponding point in the blinding coverage space area of the high beam, and the pixel size of the light intensity point is 1(m) * 1(m) * 1(m).

[0091] In the embodiment of the present invention, an automatic control method for high and low beams processes the image information captured by the camera, identifies the spatial position of the target object, and realizes the automatic switching of high and low beams based on the spatial position of the target object. There is no need to additionally increase sensors. Compared with the prior art that uses the distance from oncoming vehicles as the switching basis, the accuracy of the present invention is higher, so that the adjustment of high and low beams during driving is more timely and accurate, improving the driving safety. By controlling the high and low beams based on the first time when the high beam covers the target object and the second time when the high beam moves away from the target object, the driving safety is further improved.

[0092] Embodiment 2

[0093] Based on the same inventive concept as the automatic control method for high and low beams in the first embodiment above, as Figure 8 shown, the present invention also provides an automatic control system for high and low beams. The control system includes:

[0094] A camera 100 for collecting driving image information;

[0095] A processor 200, which is used to execute the above automatic control method for high and low beams when executed.

[0096] All the various change modes and specific examples of the automatic control method for high and low beams in the first embodiment above are equally applicable to the automatic control system for high and low beams in this embodiment. Through the detailed description of the automatic control method for high and low beams above, those skilled in the art can clearly know the automatic control system for high and low beams in this embodiment. Therefore, for the sake of simplicity of the specification, it will not be elaborated here.

[0097] Embodiment 3

[0098] Based on the same inventive concept as the automatic control method for high and low beams in the second embodiment above, the present invention also provides a vehicle, and the vehicle is installed with the above control system.

[0099] Inspired by the above-described ideal embodiments of the present invention, through the above description, relevant staff can completely make various changes and modifications without departing from the technical idea of the present invention. The technical scope of the present invention is not limited to the content in the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. An automatic control method for high and low beam lights, characterized in that, Including: Step S1: Obtain driving image information. Obtaining the image information includes processing the original image data collected by a camera to generate recognition image information. Step S2: Process the image information, identify the target object, and calculate the relevant data of the target object to obtain the spatial position and motion trajectory of the target object. The relevant data of the target object includes category, speed, direction, the distance between the self-vehicle and the target object, and the position in the image. In the step S2, it specifically includes the following steps: S21: Input the image information into a CNN network model for detection to obtain the category of at least one target object and the position of the target object in the image. S22: According to the position of the target object in the image, calculate the spatial position of the target object in the world coordinate system through the internal and external parameters of the camera. S23: Calculate the distance between the self-vehicle and the target object and the speed of the target object according to the vehicle speed of the self-vehicle and the position change of the target object between frames, and judge the direction of the target object relative to the self-vehicle. Step S3: Obtain the current state of the high beam and the blinding coverage space area of the high beam. According to the motion trajectory and the spatial position of the target object, judge whether the target object is in the blinding coverage space area of the high beam to realize automatic switching of the high and low beams. In the step S3: If the current state of the high beam is on and the target object is in the blinding coverage space area of the high beam, calculate the first time for the high beam to cover the target object according to the data of the target object, and automatically control the high beam to turn off. If the current state of the high beam is off and the target object is far from the blinding coverage space area of the high beam, calculate the second time for the high beam to move away from the target object according to the data of the target object, and automatically control the high beam to turn on.

2. The automatic control method for high and low beam lights according to claim 1, wherein The step S22 includes the following steps: Calculate the rectangular box of the target object in the image through the CNN network model. Let the angle between the optical axis of the camera and the ground in the vertical direction be , and the angle between the optical axis of the camera and the ego vehicle in the horizontal direction be . The distance calculation formula between the ego vehicle and the target object is: Where h is the installation height of the camera, f is the focal length of the camera, x is the horizontal distance between the projection point of the rectangular frame in the image and the optical axis point, y is the vertical distance between the optical axis point in the image and the lower edge line of the rectangular frame, and LA and LB are the horizontal and vertical distances of the target object from the self-vehicle respectively. In the step S23, the relative position of the target object from the host vehicle at time t is calculated by the formula (1) as (LA t , LB t ). The relative position of the target object from the host vehicle at time t + a is (LA t+a + v x dt, LB t+a + v y dt). The motion straight line of the target object from time t to time t + a is: where v x and v y are the longitudinal and lateral speeds of the host vehicle, respectively; The speed calculation formula of the target object is:

3. The automatic control method for high and low beam lights according to claim 2, characterized in that, In the step S23, judging the direction of the target object relative to the self-vehicle includes the following steps: Take LA t+a + v x dt and LA t Perform a subtraction calculation, and determine the direction of the target object relative to the host vehicle according to the calculation result: If the calculation result is greater than zero, the target object and the self-vehicle are running in the same direction. If the calculation result is equal to zero, the target object is in a stationary state relative to the self-vehicle or perpendicular to the direction of the self-vehicle. If the calculation result is less than zero, the target object and the self-vehicle are running in the opposite direction.

4. The automatic control method for high and low beam lights according to claim 3, characterized in that, In the step S3, according to the formula (2), the speed of the target object, and the speed of the self-vehicle, calculate the first time for the high beam to cover the target object and the second time for the high beam to move away from the target object.

5. The automatic control method for high and low beam lights according to claim 1, characterized in that After automatically controlling the high beam to turn off, the target object is also tracked and its trajectory is predicted. When the target object is not in the blinding coverage space area of the high beam, the high beam is automatically turned on.

6. The automatic control method for high and low beam lights according to claim 5, characterized in that, In the step S2, it is also detected according to the image information whether the target object has a rearview mirror and whether the reflective surface of the rearview mirror faces the host vehicle.

7. An automatic control system for high and low beam lights, characterized in that, The control system includes: A camera (100) for collecting driving image information; A processor (200), which is configured to execute the automatic control method of the high and low beam lights as described in any one of claims 1-6 when executed.

8. A vehicle, characterized in that, The vehicle is equipped with the control system as described in claim 7.

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