DE19640929C1 - Driver assistance device for automobile - Google Patents

Abstract

The device (6) regulates the velocity of the vehicle (1) and its relative spacing from the preceding vehicle by regulation of the vehicle engine and/or the brakes, under control of an on-board computer. An automatic steering control uses a sensor (8) detecting a guide track (4) incorporated in the road surface (2), for controlling the steering of the steered vehicle wheels via the on-board computer.

Description

The present invention relates to a device for Supporting a driver while driving, especially a motor vehicle in road traffic, with a device arranged on a vehicle for Regulation of an adjustable speed of the vehicle and to regulate the distance to a vehicle ahead Vehicle and with one arranged on the vehicle automatic steering device.

Devices for speed and distance control are for example from DE 195 09 178 C2 and DE 195 14 023 A1 known.

In such a known device, the driver a motor vehicle equipped with the device to increase traffic safety that the device for regulating an adjustable Speed and to regulate the distance to one vehicle driving ahead with the help of the distance sensor and the means for acting on the drive and / or Brake device a certain while driving Maintains a safe distance from the vehicle in front. The driver can make a desired one  Set vehicle speed and depending this desired speed is achieved using the On-board computer that for that speed required safety distance calculated by Acting the means to act on the Drive device and / or braking device for this speed calculated safety distance adhered to. For this, for example, on the Drive device are acted so that the Fuel supply reduced or interrupted or the Braking device of the vehicle - if necessary with the help of a hydraulic system - is operated.

With the help of the combined speed and Distance control device is the vehicle driver on the effectively supports the manner described. The disadvantage is however, that the vehicle driver nonetheless while driving focused on traffic to get to the vehicle keep on the road and the desired route to adhere to. Especially on longer journeys, the Driver of the vehicle lack of concentration or Get fatigue that is in control of you your own vehicle and traffic safety can affect. It often happens because of such signs of fatigue with accidents serious consequences, such as rear-end collisions on highways. Especially truck drivers or coaches that are in use for several hours are and are regularly subject to time pressure, often cause accidents because they are tired. Though are certain maximum vehicles for professional drivers and rest breaks are prescribed, but will be Regulations are often not complied with.

The German magazine "Electronics" 1984, No. 15, Pages 41 to 46 discloses an apparatus in which  Buses are routed along a guide cable. The Guide cable is laid in the middle of or on the road. Sensors on the bus control using a Control electronics a servo hydraulic one Steering device. The omnibus is thus on the target track led along. The bus becomes automatic directed. However, the driver must have the desired one Vehicle speed as well as the distance to one leading vehicle in the conventional way with the help of his mind and thus subjectively adjust. It is still the full attention of the driver necessary, which leads to driver fatigue. The This affects traffic safety negatively.

The present invention is based on the object a device of the type mentioned provide the benefits of the known technical solutions combined and to increase the Road safety a maximum support of one Motor vehicle driver offers when driving.

The task is characterized by the features of the claim 1 solved.

The invention ensures that the driver of a with the invention  Device equipped vehicle largely relieved while driving is because the device according to the invention takes over the speed control of your own vehicle, the distance control to the vehicle in front Vehicle, as well as driving your own vehicle along the guiding lane on the Roadway is arranged. In this way the vehicle is "automatically" along the specified route. The driver is only activated as well as to deactivate the device. It can be used during the "automati "ride monitor the function of the device according to the invention or even turn to other activities, such as making calls or the like. The vehicle can be moved safely, even if the driver of the vehicle certain Shows signs of fatigue. In addition, the driver can do this himself at any time Take control of the vehicle and the device according to the invention disable what may be required, for example, to overtake a vehicle can or to change the route in areas where there is no guidance lane is provided.

The device according to the invention is particularly suitable for trips on Motorways or highways with heavy traffic and some of the vehicles involved drives a similar speed, for example for convoys of commercial or military trucks is often the case. Are several driving within a vehicle column Vehicles formed with the device according to the invention results in a dynamic system of vehicles, in which a desired, preselectable speed and a required between the vehicles predictable safety distance is maintained. Any deviations from the desired speed and the associated safety distance automatically corrected while a vehicle is being steered along the guidance lane.

The device also offers night driving or poor visibility due to fog special security, because a required safety distance is always vehicle in front and at the same time the one specified by the guidance lane Traveled. According to the invention, the problem that professional drivers often experience fatigue due to the pressure of deadlines suffer, be weakened, because while driving with the help of Invention According to the device, the driver of the vehicle is largely relieved, so that for a safe drive his full attention is not required.

A particularly preferred embodiment of the device according to the invention  is characterized in that the sensor on an electromagnetic or magnetic field responds and emits a track signal, the strength of the distance depends on the sensor and the guide track. With such a sensor, the automatic steering of the vehicle along the guide track in a simple way be made. As soon as the strength of the track signal due to a certain lateral, measured transverse to the longitudinal extent of the lead track Distance of the sensor from the lead track falls below a certain value, so the steering device will adjust the position of the wheels of the vehicle thereby reducing the lateral distance between the sensor and the guide track, so that the vehicle is steered along the guide track.

This embodiment is developed in which the lead track is at least one has electrical cable that can be inserted into a roadway and connected to a voltage source is connectable. Such a cable emits an electromagnetic field, that can be detected with the help of the sensor, so that the sensor detects the track signal emits which is used to steer the vehicle along the guide track.

According to an alternative development of the embodiment, the guide track has at least one magnetically coded tape on or below the surface is arranged on a carriageway or on a track running next to the carriageway Traffic barrier is attached. This training is also easy Way provided a guide track for automatic steering of the vehicle is used and for example along a trunk road or motorway marked the specified route. Finally, according to another Development of the invention, the guide track made of spaced magnets be formed, which are arranged in the region of the surface of a roadway.

An alternative embodiment of the invention is characterized in that the Steering device has a so-called power steering, in which the location at least one wheel of a motor vehicle with the help of at least one inside a cylinder arranged piston and one displaceable by the piston Hydraulic fluid is adjustable. Power steering systems are used by many manufacturers offered by motor vehicles and allow on using a hydraulic fluid constructively relatively simple way of integration into the with the help of Steering device emitted by the track signal sensor.

According to a further advantageous embodiment of the invention, the  Steering device with the computer of speed and Distance control device and is connected with Computer controlled and regulated. At this One embodiment is sufficient for a computer to control and Regulation of the entire device according to the invention, see that the expenditure on equipment can be kept low.

Exemplary embodiments of the invention are explained in more detail below with reference to the figures . Show it:

Figure 1 shows a motor vehicle equipped with a device according to the invention and a guide track inserted into a roadway in a schematic view.

Fig. 2 shows the embodiment shown in Figure 1 in a schematic view from above.

Fig. 3 shows a further schematic representation of the embodiment shown in Figs. 1 and 2 with the individual components.

In Figs. 1 and 2 equipped with the inventive apparatus the motor vehicle 1 is shown schematically which is moving on a road 2, which is provided with a scannable guide track. 4 The device shown essentially comprises a speed and distance control device 6 for regulating an adjustable speed of the vehicle 1 and for regulating the distance to a vehicle in front (not shown), furthermore the guide track 4 arranged along a predetermined route, one on the vehicle 1 arranged sensor 8 for scanning the guide track 4 and a steering device 10 also arranged on the vehicle 1 for automatically steering the vehicle 1 . The vehicle 1 can be designed as a passenger car or a truck.

The combined speed and distance control device 6 is arranged essentially in the front area of the vehicle and, as can be seen from FIGS. 2 and 3, essentially comprises a speed sensor 12 for detecting the current vehicle speed and a distance sensor arranged in the front area of the vehicle 1 14 for detecting the distance to the vehicle in front and means 34 for acting on a drive device 16 of the vehicle 1 and / or for acting on a braking device 18 of the vehicle 1 and an on-board computer for controlling and regulating the components of the speed and distance rule described above Facility 6 .

In the exemplary embodiment, the speed sensor 12 is designed as a speed sensor for measuring the speed of a front wheel 20 . The speed sensor 12 provides a signal that is transmitted to an on-board computer 22 (see FIG. 3) within the device 6 . A minimum distance value is calculated in the computer 22 as a function of the recorded speed values.

A desired speed value can be entered into the computer 22 and the entered speed value can be adjusted with the aid of the device 6 by comparing the actual speed value of the vehicle 1 recorded with the aid of the speed sensor 12 with the entered speed value . For this purpose, the drive device 16 and possibly the braking device 18 are actuated by means 34 for acting.

The distance sensor 14 determines the actual distance value to a preceding vehicle (not shown) with the aid of electromagnetic waves which are emitted by the distance sensor 14 and reflected by the preceding vehicle. The actual distance can be determined in the computer of the device 6 via a transit time measurement and compared with the minimum distance value. If the actual distance value falls below the calculated minimum distance value, the vehicle 1 is decelerated with the aid of the means 34 for acting on the drive device 16 and / or braking device 18 - described in more detail below with reference to FIG. 3, so that the calculated minimum distance value is restored. In this way, the distance to a vehicle in front is regulated.

As can be seen from the illustration of individual components of the device according to the invention in FIG. 3, the computer 22 has a memory device 24 , a processor 26 and an operating and display device 28 . On the input side, the computer 22 is connected to a first analog / digital converter 30 , which converts the analog signals emitted by the speed sensor 12 , the distance sensor 14 and the sensor 18 for scanning the guide track 4 into digital signals and to the computer 22 transmits.

On the output side, the computer 22 is also connected to a digital / analog converter 32 , by means of which digital signals output by the computer 22 can be converted into analog signals. The analog signals can be transmitted from the digital / analog converter 32 to the means 34 indicated by the dashed line for acting on the drive device 16 or the braking device 18 .

In the exemplary embodiment, the means 34 have both an electric servo motor 36 for acting on the carburetor or injection system (not shown) of the drive device 16 and a pneumatic or hydraulic actuating device 38 for actuating the braking device 18 .

As can be seen from FIGS. 2 and 3, the steering device 10 acts on the separately pivotable front wheels 20 of the vehicle 1 in order to adjust the position of the wheels 20 in order to be able to change the direction of travel of the vehicle 1 . The steering device 10 has, in a manner not shown, at least one piston arranged within a cylinder, which can be moved within the piston by means of a hydraulic fluid in which a variable pressure can be generated. The piston is coupled to a steering linkage that acts on the wheels 20 . When the piston moves, the steering linkage is moved and the wheels 20 change their position in a known manner. The pressure in the hydraulic fluid can be generated, for example, with the aid of a gear pump and can be varied with the aid of adjustable throttle valves. Such a steering device 10 is usually referred to as power steering.

The steering device 10 is connected to the digital / analog converter 32 in order to receive a control signal from the converter 32 which is used to adjust the position of the wheels 20 (in the manner described above). The steering device 10 is controlled and actuated with the aid of a Spursig nals emitted by the sensor 8 with the interposition of the analog / digital converter 30 of the computer 22 and the digital / analog converter 32 in order to automatically steer the vehicle 1 along the guide track 4 .

For automatic steering of vehicle 1, sensor 8 provides a track signal, the strength of which depends on the distance between sensor 8 and guide track 4 (see FIGS . 1 and 2). The greater the distance between sensor 8 and guide track 4 , the weaker the track signal emitted by sensor 8 . The "lateral" distance between the sensor 8 and the guide track 4 is crucial for steering the vehicle 1 . A “lateral” distance is to be understood here to mean a distance transverse to the longitudinal extent of the guide track 4 .

The track signal is digitized in the analog / digital converter 30 and fed to the computer 22 . In the computer 22, the digitized signal using a stored in the memory device 24 programming (software) is processed by being closed by the provided by the sensor 8 trace signal on the actual lateral distance (in the above sense) of the sensor 8 from the guide track 4 . A digital control signal is provided by the computer 22 and transmitted to the digital / analog converter 32 . The transmitted control signal is converted by the converter 32 into an analog signal and transmitted to the steering device 10 .

The steering device 10 is actuated by this transmitted signal such that the actual lateral distance between the sensor 8 and the guide track 4 is minimized. In this way, the vehicle can be guided or steered along the guide track 4 .

The sensor 8 responds to an electromagnetic or magnetic field emanating from the lead track 4 . In the exemplary embodiment, the guide track 4 is designed as an electrical cable which is connected to a voltage source. As soon as a current flows through the cable, an electromagnetic field forms around the cable, which can be detected by the sensor 8 . If the actual distance between sensor 8 and the cable is reduced, the track signal emitted by sensor 8 increases. The cable is arranged approximately centrally in the middle directly below the surface of the carriageway 2 .

Alternatively, the guide track 4 can have a magnetically coded tape which is used instead of the cable. This band can also be arranged under the surface of a roadway 2 . The tape has magnetic zones at intervals, which are surrounded by a magnetic field which can be detected by the sensor 8 , so that the latter provides and emits a track signal. The belt can alternatively be attached to a traffic guardrail. Furthermore, the guide track could be formed from magnets spaced apart from one another, which are arranged in the region of the surface of the roadway 2 and likewise generate a magnetic field.

The sensor 8 can be arranged in a manner not shown with the help of a rod in comparison to the illustration according to FIG. 1 at a smaller vertical distance from the guide track 4 .

Claims (6)

1. Device for assisting a vehicle driver when driving, in particular a motor vehicle in road traffic, with a device ( 6 ) arranged on a vehicle ( 1 ) for regulating an adjustable speed of the vehicle ( 1 ) and for regulating the distance from a vehicle in front, the a speed sensor ( 12 ) for detecting the vehicle speed and a distance sensor for detecting the distance to the preceding vehicle, means ( 34 ) for acting on a drive device ( 16 ) and / or braking device ( 18 ) of the vehicle ( 1 ), with one on the vehicle ( 1 ) arranged automatic steering device ( 1 ) which has a sensor ( 8 ) for detecting a scannable guide track ( 4 ) which is arranged along a predetermined route and which emits a track signal while driving, whereby the vehicle ( 1 ) automatically along the guide track ( 4 ) is steered, as well as with a storage unit ( 24 ) and one Processor ( 26 ) having computer ( 22 ) for controlling and regulating the components. 2. Device according to claim 1, characterized in that the sensor ( 8 ) responds to an electromagnetic or magnetic field and emits a track signal, the strength of which depends on the distance between the sensor ( 8 ) and guide track ( 4 ). 3. Apparatus according to claim 2, characterized in that the guide track ( 4 ) has at least one electrical cable which is inserted into a roadway ( 2 ) and can be connected to a voltage source. 4. The device according to claim 2, characterized in that the guide track has at least one magnetically coded tape which is arranged on or below the surface of a roadway ( 2 ) or is attached to a traffic guardrail extending next to the roadway ( 2 ). 5. The device according to claim 2, characterized in that the guide track ( 4 ) is formed from spaced magnets, which are arranged in the region of the surface of a roadway ( 2 ). 6. The device according to at least one of the preceding claims, characterized in that the steering device ( 10 ) has a so-called power steering, in which the position of at least one wheel ( 20 ) of a motor vehicle with the aid of at least one piston arranged within a cylinder and one by the piston displaced hydraulic fluid is adjustable.