RU2737069C1 - Automatic vehicle wheel braking system - Google Patents

Abstract

FIELD: machine building.SUBSTANCE: disclosed is wheel vehicle automatic braking system. Proposed system comprises wheel rpm transducers (1, 2, 3, 4) and technical vision device. Microcontroller (5) comprises unit (10) for analysing signals of wheel rpm sensors (1, 2, 3, 4), unit (11) for estimating vehicle motion parameters, unit (12) for identification of maximum values of friction coefficients of wheels sliding, unit (13) for prediction of maximum deceleration without wheels blocking, unit (14) for restriction of slowdown by rear obstacle, unit (15) optimization of control for prevention of collisions, unit (16) for generation of control signals, unit (17) for generating control actions on vehicle control elements (18): brakes (19), accelerator (20), steering wheel (21). Above units are made on the basis of microcontroller (5) with possibility of program execution. Threshold of actuation of brake system in unit (15) is set programmatically in multiple times less than maximum deceleration without blocking wheels to compensate for effect of possible prediction errors due to unaccounted factors. System comprises device (22) for input and display of tuning data. Device (23) for generating sound and light alarm transmits emergency control signal to unmanned vehicles located behind, and is connected to control device (17).EFFECT: identification of adhesion of wheels with road surface, prediction of maximum deceleration without wheels blocking, limitation of slowdown by rear obstacle, optimum braking control.1 cl, 1 dwg

Description

The invention relates to the automotive industry, in particular, to methods and devices for increasing the active safety of vehicles, including unmanned vehicles.

Known vehicle control device (see US published application No. US 20190210597 A1, applicants DENSO CORPORATION, publ. 11.07.2019), designed to prevent collisions with objects in the front hemisphere, which consists of a collision avoidance control unit, a unit for evaluating the state of actuators , the block for setting the states of the executive mechanisms, including the brake system and steering. Obstacle avoidance is provided on the initiative of the driver without taking into account the automatic detection of obstacles in adjacent lanes, both simultaneously with automatic braking and without it.

The disadvantages of this device are the absence of restrictions on the amount of braking deceleration necessary to prevent collisions with a rear passing obstacle, insufficient reliability of data on the sliding friction coefficients of the wheels determined from the readings of the ambient temperature sensor or from the weather map, as well as the lack of automation of the obstacle avoidance maneuver.

A device for assessing the coefficient of adhesion to the road surface and a method for its implementation (see South Korean patent No. KR 1020180123366, applicants Korea Automotive Technology Institute, publ. 08.11.2019), which is designed to identify the top values of the coefficients of sliding friction of wheels for trial test braking to determine the maximum deceleration of a wheeled vehicle. An apparatus for evaluating a coefficient of friction using preventive braking may include: a braking coefficient adjusting unit configured to adjust a braking force distribution coefficient of the front and rear wheels; a detector for determining the amount of slip and the coefficient of friction in contact of the tire with the road surface during preventive braking in accordance with the coefficient of distribution of braking forces of the front and rear wheels and a detector of the coefficient of friction for determining the coefficient of friction of the road surface based on the detected amount of slip and the coefficient of friction in contact of the tire with the road surface.

The disadvantage of the proposed device is the limited possibility of identifying the parameters of tire adhesion to the surface by conditions of preventive braking. When driving on surfaces with a variable coefficient of adhesion, this method is not applicable. In driving conditions, the time intervals of braking, including auxiliary ones, take up to 10% of the total time, which does not allow the identification data to be considered adequate.

A device and method for automatic braking of a vehicle is known (see Chinese patent No. CN 104875730 B, applicant QOROS AUTOMOTIVE CO., LTD, publ. 05/08/2018), which includes a front obstacle detection module, a rear obstacle detection module, a control module and brake module. In the considered device and method, the values of the time to collision with the front and rear obstacles are calculated, based on their analysis, a control action on the brakes is formed, which should ensure the prevention of collisions with obstacles in the lane.

The disadvantages of the considered device are the absence of the intended bypass of the obstacle in the event of an imminent collision with obstacles in the lane, and also there is no identification of the coefficient of adhesion of tires to the surface, which determines the upper limit of braking deceleration without blocking the wheels.

Known automobile automatic control device for preventing collisions with obstacles using the sensor of the Internet of things (see the published application of the People's Republic of China No. CN 106915347 A, applicants TIANJIN HUAFANG TECH CO LTD, publ. 04.07.2017), which includes a radar module for determining the distance, a machine vision module , brake control module and steering wheel control module. Avoiding the front obstacle is performed when the vision module does not detect obstacles in adjacent lanes. If obstacles in adjacent lanes are detected, then braking is performed according to the data of the radar module for determining the distance in the front hemisphere.

The disadvantages of the proposed technical solution are the lack of identification of the coefficients of adhesion of tires to the surface, which determines the upper limit of braking deceleration without blocking the wheels, as well as the lack of limitation of deceleration, determined by the distance to the rear obstacle in the lane.

The closest in technical essence is a vehicle collision warning and avoidance system, which uses combined automatic heading and brakes control and contains means for determining threshold values that identify the time before colliding with an obstacle and based on the analysis of the parameters of the object's movement, including the coefficients of tire adhesion to the surface and the obstacle is either warning, braking, or obstacle avoidance (see US Patent No. US 8527172 B2, Applicants Nikolai K. Moshchuk [US], Shih-Ken Chen [US], Chad T. Zagorski [US], Aamrapali Chatterjee [US], publ. 03.09.2013).

The disadvantages of the considered system are the lack of taking into account the parameters of the movement of the rear associated obstacle when braking on the lane and the absence of restrictions on the amount of braking deceleration necessary to prevent a collision with the rear associated obstacle.

The technical problem to be solved by the present invention consists in identifying the grip of the wheels with the road surface, predicting the greatest deceleration without blocking the wheels, limiting deceleration by a rear obstacle, optimal braking control to prevent collisions with obstacles and the formation of control actions on the brakes, accelerator and steering wheel , as well as in the activation of sound and light alarms in dangerous situations.

The technical problem posed is solved in that, according to the proposed invention, a system for automatic braking of a wheeled vehicle, containing sensors 1, 2, 3, 4 of the wheel speed, electrically connected to the microcontroller device 5 for processing information, through communication lines with the interface device 6, a vision device for the front 7 and rear 8 hemispheres, electrically connected to the microcontroller device 5 for information processing by means of communication lines with the device 9 for interfacing vision devices with the microcontroller device 5, the microcontroller device 5 for processing information includes a unit 10 for analyzing signals from sensors 1, 2, 3, 4 frequencies wheel rotation, unit 11 for estimating vehicle movement parameters, unit 12 for identifying the maximum values of wheel sliding friction coefficients, unit 13 for predicting the greatest deceleration without blocking the wheels, unit 14 for limiting deceleration by a rear obstacle, block 15 for optimizing control to prevent collisions, block 16 for generating control signals, block 17 for generating control actions on controls 18 of the vehicle: brakes 19, accelerator 20, steering wheel 21,

moreover, in the system, blocks 10 for analysis, 11 for evaluation, 12 for identification, 13 for prediction, 14 for restrictions, 15 for optimization, 16 for generating control signals are made on the basis of a microcontroller device 5 with the possibility of program execution of block 10 for analyzing signals from sensors 1, 2, 3, 4 of rotation frequencies wheels, unit 11 for estimating vehicle motion parameters, unit 12 for identifying maximum values of sliding friction coefficients of wheels, unit 13 for predicting the greatest deceleration without blocking wheels, unit 14 for limiting deceleration by a rear obstacle, unit 15 for optimizing braking control, unit 16 for generating control signals for control actions on the controls 18 of the vehicle, while the system is additionally equipped with a device 22 for input and display of tuning data, a device 17 for generating control actions on the controls for brakes 19, an accelerator 20 and a steering wheel 21, and a device 23 for forming sound and light alarm is made with the possibility of transmitting an emergency control signal to unmanned vehicles located at the back and connected to the device 17 for generating control actions on the vehicle controls (see. Figure).

Among the advantages, i.e. The technical results achieved by the automatic braking system include:

- the ability to prevent collisions with obstacles following in the same direction in front and behind the vehicle, by automatically limiting deceleration during braking, timely notification and transmission of an emergency signal to neighboring unmanned vehicles in dangerous situations;

- the possibility of automatic analysis of collision avoidance scenarios that provide for a safe bypass of the front obstacle in the case when a collision with an obstacle in the traffic lane cannot be prevented by braking;

- identification of the maximum values of the coefficient of sliding friction of wheels is carried out in all modes of vehicle movement, including acceleration, movement with a constant speed and braking;

- exclusion of the intermittent braking mode, which reduces its effectiveness on uneven and slippery surfaces;

- preventing the wheels from blocking during braking while maintaining directional control;

- keeping the system operational in the event of a malfunction in no more than 3 out of 4 wheel speed sensors.

The technical result is achieved by creating an automatic braking system for a wheeled vehicle, in which the blocks are connected in a certain way.

The drawing (Figure) shows a block diagram of an automatic braking system for a wheeled vehicle.

The automatic braking system of a wheeled vehicle contains sensors 1, 2, 3, 4 of the wheel speed, electrically connected to the microcontroller device 5 for processing information, through communication lines with the interface device 6, vision devices for the front 7 and rear 8 hemispheres, electrically connected with a microcontroller device 5 for processing information through communication lines with a device 9 for interfacing vision devices with a microcontroller device 5, a microcontroller device 5 for processing information includes a unit 10 for analyzing signals from sensors 1, 2, 3, 4 of wheel speeds, a unit 11 for estimating vehicle movement parameters, block 12 for identifying the maximum values of the sliding friction coefficients of the wheels, block 13 for predicting the greatest deceleration without blocking the wheels, block 14 for limiting deceleration by the rear obstacle, block 15 for optimizing control to prevent collisions, block 16 for forming a system control channels, block 17 for generating control actions on the controls 18 of the vehicle: brakes 19, accelerator 20, steering wheel 21, characterized in that the system has blocks 10 for analysis, 11 for evaluation, 12 for identification, 13 for forecasting, 14 for restrictions, 15 for optimization, 16 for generating control signals are made on the basis of microcontroller device 5 with the possibility of software execution of unit 10 for analyzing signals from sensors 1, 2, 3, 4 of wheel speeds, unit 11 for estimating vehicle motion parameters, unit 12 for identifying maximum values of sliding friction coefficients of wheels, unit 13 predicting the greatest deceleration without blocking the wheels, block 14 for limiting deceleration by a rear obstacle, block 15 for optimizing braking control, block 16 for generating control signals for controlling actions on vehicle controls 18, block 10 for analyzing signals from sensors 1, 2, 3, 4 of wheel speeds completed with the possibility of detecting faulty sensors, the data of which are excluded from further analysis, the block 12 for identifying the maximum values of the sliding friction coefficients is made with the possibility of evaluating these parameters, at least according to a signal from one wheel speed sensor on each side, the block 13 for predicting the greatest deceleration without blocking the wheels is configured to evaluate this parameter in the absence of a signal from the wheel speed sensors according to the tuning data input from the input device 22 and displaying the tuning data, the block 14 for limiting deceleration by the rear obstacle is made taking into account the restrictions on safe rebuilding into adjacent rows, the block 15 for optimizing control braking is made with the ability to automatically select the best sequence of control actions on the brakes, accelerator and steering wheel to prevent collisions with obstacles in the front and rear hemispheres, the signal generation unit 16 is controlled and is configured to activate a light alarm about imitation of braking in the event of a dangerous reduction in the distance with a rear obstacle and activate an alarm in case of predicting an imminent collision with obstacles, while the response threshold of the braking system in the block 15 for optimizing braking control is set by software in a multiple number of times less than the maximum deceleration without blocking the wheels to compensate for the influence of possible forecast errors due to unaccounted factors, while the system is additionally equipped with a device 22 for input and display of tuning data, a device 17 for generating control actions on the brake controls 19, an accelerator 20 and a steering wheel 21, and a device 23 the formation of sound and light alarms is made with the possibility of transmitting an emergency control signal to unmanned vehicles located at the back and is connected to the device 17 for generating control actions on vehicle controls (see. Figure).

The proposed system works as follows.

When the vehicle is moving, the sensors 1, 2, 3, 4 generate signals about the frequencies of rotation of the wheels of the vehicle, and since they are electrically connected to the microcontroller device 5, these signals are constantly fed to the microcontroller device 5 for information processing via communication lines with the interface device 6 , which includes the program unit 10 for analyzing the signals of the wheel speed sensors, which compares their value with the operating range of the sensor signals and identifies the sensors that have malfunctions in the form of a signal loss at the boundary time interval, while the automatic readings of such a sensor are excluded from further analysis (see . Figure).

Data on the spatial position of obstacles in the front and rear hemispheres are received from vision devices for the front 7 and rear 8 hemispheres, electrically connected to the microprocessor device 5 for information processing by means of communication lines with the device 9 for interfacing vision devices with the microcontroller device 5.

Further, in the microcontroller device 5 for processing information, the program unit for evaluating 11 parameters of the vehicle's movement compares the signals from the sensors 1, 2, 3, 4 of the wheel speed of the vehicle and receives data characterizing the parameters of the vehicle's movement (Certificate of state registration of the computer program No. 2009616286. The program "INCA-SPORT version 2.0" / Buznikov S.E., Elkin D.S.// Rospatent 2009).

In block 12 for identifying the maximum values of the sliding friction coefficients of wheels based on the obtained estimates of the velocities of longitudinal sliding of wheels, traction and braking accelerations of the center of mass, the angle of rotation of the steered wheels, the distribution of masses along the axes of the vehicle, the maximum values of the coefficients of sliding friction of wheels are identified using software this function (Certificate of state registration of a computer program No. 2007610818 "Identification of the maximum values of the sliding friction coefficients of the wheels of a car" / Buznikov S.E., Elkin D.S.// Rospatent, 2007).

In block 13 for predicting the greatest deceleration without blocking the wheels, on the basis of the obtained estimates of the maximum values of the sliding friction coefficients of the wheels and the tuning data of the vehicle, the boundary values of the control actions on the wheel brakes at the border of their blocking are determined and from them and the greatest control effect on the brakes, limited by the design of the brake system the minimum is selected, which ensures the fulfillment of sufficient conditions for the absence of wheel blocking during braking.

The value of the found value of the boundary control action on the braking system is used to determine the maximum deceleration of the vehicle under specific driving conditions.

In block 14 of limiting the deceleration of the rear obstacle, the data on the distances to the nearest obstacles in the front and rear hemispheres, coming from the vision devices 16 and 17 of limiting the deceleration of the rear obstacle, are processed by software and allow obtaining information about the speed, relative position and acceleration of obstacles in the lane vehicle and on adjacent traffic lanes (Certificate of state registration of the computer program No.2019618610 "Program for monitoring the position of the slave unmanned vehicle relative to the stern of the leading vehicle according to the video camera" / Buznikov S.E., Lutsenko E.V., Strukov V.O. , Loginov I.D. // Rospatent, 2019, Certificate of state registration of the computer program No. 2019662025 "Program for determining the relative spatial position of the driven car relative to the leading one according to the radar data" / Buznikov S.E., Elkin D.S, Strukov V. O., Loginov I.D. // Rospatent, 2019).

The value of the deceleration of the controlled vehicle is determined by the distance to the rear obstacle and its speed, limiting its deceleration at which a collision with a rear obstacle is excluded. The minimum of the largest deceleration without wheel blocking and rear obstacle limiting deceleration forms the upper limit of permissible deceleration, ensuring the prevention of wheel locking and collision with a rear obstacle.

In block 15 of the optimization of braking control by the distance to the front obstacle and its speed, the required deceleration value is determined, sufficient to prevent a collision with the front obstacle (Certificate of state registration of the computer program No. 2017610762 "Program for the control of automatic braking of a wheeled vehicle" / Buznikov S. E., Elkin D.S., Strukov V.O. // Rospatent, 2017). If the value of the required deceleration exceeds the threshold level and does not exceed the upper limit of permissible decelerations, then a control signal for the brake system and a control signal for the accelerator are generated. The value of the threshold level of deceleration is set in the tuning data in a certain number of times less than the maximum deceleration without locking the wheels to compensate for the influence of unaccounted factors when predicting the greatest deceleration without locking the wheels. Among the unaccounted for factors affecting the dynamic characteristics of braking are the presence of moisture on the working surfaces of the brakes, their temperature, the state of the road surface with variable sliding friction coefficients, which is due to the alternation of areas of clean asphalt and asphalt covered with a layer of ice and snow.

If the required deceleration exceeds the upper limit of permissible decelerations, then if the conditions for preventing collisions with obstacles in adjacent traffic lanes are met, a sequence of steering control signals is generated to avoid the obstacle.

If the deceleration limitation value by the rear obstacle turns out to be less than the maximum deceleration without blocking the wheels, then in the block 15 of optimization of braking control, a signal is generated to simulate braking in order to increase the distance with the rear obstacle to a safe level and then is transmitted to the block 16 for generating control signals for control actions, and further to the device 23 for generating sound and light alarms.

If the required deceleration value exceeds the upper limit of permissible decelerations and the conditions for preventing collisions with obstacles are not met, the sound and light alarm generating device 23 generates a sound and light alarm activation signal in order to warn others about an imminent collision.

The block 16 for generating control signals for control actions on the vehicle controls 18 is implemented in software in the microcontroller device 5 based on the choice of the optimal scenario of braking control in the block 15 for optimizing braking control.

In the block 17 for generating control actions on the controls 18 of the vehicle, the control signals of the block 16 are converted by means of the actuators into control actions on the controls 18 of the vehicle: brakes 19, accelerator 20, steering wheel 21.

The device 22 input and display of adjustment data is intended for input, correction and display of settings of the proposed system.

The device 23 for generating sound and light alarms is used both for its main purpose and to simulate braking in the case when the distance to the rear vehicle is less than safe, and also in the case of predicting a collision with obstacles, its emergency mode is activated.

The difference in the design features of the proposed system and its functioning in comparison with the known designs are described below.

If in the system the blocks 10 for analysis, 11 for evaluation, 12 for identification, 13 for prediction, 14 for restrictions, 15 for optimization and 16 for generating control signals are made on the basis of the microcontroller device 5 in the form of program blocks operating with the possibility of programmatically executing the functions of the block 10 for analyzing signals from sensors 1, 2, 3, 4 wheel speed, unit 11 for estimating vehicle motion parameters, unit 12 for identifying maximum values of wheel sliding friction coefficients, unit 13 for predicting the greatest deceleration without blocking the wheels, unit 14 for limiting deceleration by a rear obstacle, unit 15 for optimizing braking control, unit 16 generating signals for the unit 17 of control actions on the vehicle controls 18, such an implementation can significantly speed up the processes of analyzing the signals of the sensors 1, 2, 3, 4 of the wheel speed, estimating the parameters of the vehicle movement, identifying the maximum values the coefficients of sliding friction of wheels, predicting the greatest deceleration without blocking the wheels, limiting deceleration by a rear obstacle, optimizing braking control, correctly assess the situation and promptly form a sequence of control actions on the controls 18 of the vehicle (see. Figure).

Moreover, the unit 10 for analyzing the signals of the sensors 1, 2, 3, 4 of the wheel speeds is made with the possibility of detecting faulty sensors, the data of which are excluded from further analysis, the block 12 for identifying the maximum values of the sliding friction coefficients of the wheels is made with the possibility of evaluating these parameters, at least according to a signal from one wheel speed sensor on each side, the unit 13 for predicting the maximum deceleration value without blocking the wheels is made with the possibility of evaluating this parameter in the absence of signals from the wheel speed sensors according to the tuning data input from the device 22 for input and display of tuning parameters, the unit 14 limiting deceleration by the rear obstacle is made with the possibility of taking into account the restrictions on safe lane changes to adjacent rows, the block 15 for optimizing braking control is made with the possibility of automatically selecting the best sequence of control actions on the brakes 19, the accelerator 20 and the steering wheel with 21 to prevent collisions with obstacles in the front and rear hemispheres, the block 16 for generating control signals is configured to activate a light alarm when imitating braking in the event of a dangerous reduction in the distance by a rear obstacle and activating an emergency light and sound alarm in case of predicting an imminent collision with obstacles, when In this case, the response threshold of the braking system in block 15 is set by software to a multiple of the maximum deceleration without blocking the wheels to compensate for the influence of possible forecast errors and unaccounted for factors.

Claims (1)

The automatic braking system of a wheeled vehicle contains sensors (1, 2, 3, 4) of the wheel speed, electrically connected to the microcontroller device 5 for processing information through communication lines with the interface device (6), vision devices for the front (7) and rear ( 8) hemispheres, electrically connected to the microcontroller device (5) for processing information by means of communication lines with the device (9) for pairing vision devices with a microcontroller device (5), the microcontroller device (5) for processing information includes a unit (10) for analyzing sensor signals (1 , 2, 3, 4) wheel speeds, unit (11) for estimating vehicle motion parameters, unit (12) for identifying maximum values of sliding friction coefficients of wheels, unit (13) for predicting the greatest deceleration without blocking the wheels, unit (14) for limiting deceleration rear obstacle, block (15) control optimization to avoid collisions the unit (16) for generating control signals, unit (17) for generating control actions on the controls (18) of the vehicle: brakes (19), accelerator (20), steering wheel (21), characterized in that the system contains blocks ( 10) analysis, (11) estimation, (12) identification, (13) prediction, (14) constraints, (15) optimization, (16) generation of control signals are made on the basis of a microcontroller device (5) with the possibility of program execution of the block (10 ) analysis of signals from sensors (1, 2, 3, 4) of wheel rotation frequencies, unit (11) for estimating vehicle motion parameters, unit (12) for identifying maximum values of sliding friction coefficients of wheels, unit (13) for predicting the greatest deceleration without blocking the wheels, a unit (14) for limiting deceleration by a rear obstacle, a unit (15) for optimizing braking control, a unit (16) for generating control signals for controlling actions on the vehicle controls (18), the unit (10) for analyzing the signals of the sensors (1, 2, 3, 4) of the wheel speed is configured to identify faulty sensors, the data of which are excluded from further analysis, the unit (12) for identifying the maximum values of the sliding friction coefficients is configured to evaluate these parameters, at least according to the signal from one wheel speed sensor on each side, the unit (13) for predicting the greatest deceleration without blocking the wheels is configured to estimate this parameter in the absence of a signal from the wheel speed sensors according to the tuning data input from the input device (22) and display of the tuning data, the block (14) for limiting the deceleration by the rear obstacle is made taking into account the restrictions on safe lane change to adjacent rows, the block (15) for optimizing the braking control is made with the possibility of automatically selecting the best sequence of control actions on the brakes, accelerator and steering wheel to prevent collisions with obstacles in the front and rear hemispheres, the block (16) for generating control signals is configured to activate a light alarm about imitation of braking in the event of a dangerous reduction in the distance with a rear obstacle and activate an alarm in case of predicting an inevitable collision with obstacles, while the brake response threshold of the system in the block (15) for optimization of braking control is set by software in a multiple number of times less than the maximum deceleration without blocking the wheels to compensate for the influence of possible forecast errors due to unaccounted factors, while the system is additionally equipped with a device (22) for input and display of tuning data, a device ( 17) the formation of control actions on the controls for the brakes (19), the accelerator (20) and the steering wheel (21), and the device (23) for the formation of sound and light alarms is configured to transmit an emergency control signal to unmanned vehicles means located at the rear, and is connected to the device (17) for generating control actions on the vehicle controls.

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