CN115384461B - Automatic braking method and system for commercial vehicle and commercial vehicle - Google Patents

Automatic braking method and system for commercial vehicle and commercial vehicle Download PDF

Info

Publication number
CN115384461B
CN115384461B CN202211012755.4A CN202211012755A CN115384461B CN 115384461 B CN115384461 B CN 115384461B CN 202211012755 A CN202211012755 A CN 202211012755A CN 115384461 B CN115384461 B CN 115384461B
Authority
CN
China
Prior art keywords
commercial vehicle
braking
load
strategy
automatic
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202211012755.4A
Other languages
Chinese (zh)
Other versions
CN115384461A (en
Inventor
王晓亮
樊华春
于勤
曾应龙
廖程亮
徐炜
张周平
袁欣
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Jiangxi Isuzu Motors Co Ltd
Original Assignee
Jiangxi Isuzu Motors Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Jiangxi Isuzu Motors Co Ltd filed Critical Jiangxi Isuzu Motors Co Ltd
Priority to CN202211012755.4A priority Critical patent/CN115384461B/en
Publication of CN115384461A publication Critical patent/CN115384461A/en
Application granted granted Critical
Publication of CN115384461B publication Critical patent/CN115384461B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T7/00—Brake-action initiating means
    • B60T7/12—Brake-action initiating means for automatic initiation; for initiation not subject to will of driver or passenger
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T7/00—Brake-action initiating means
    • B60T7/12—Brake-action initiating means for automatic initiation; for initiation not subject to will of driver or passenger
    • B60T7/22—Brake-action initiating means for automatic initiation; for initiation not subject to will of driver or passenger initiated by contact of vehicle, e.g. bumper, with an external object, e.g. another vehicle, or by means of contactless obstacle detectors mounted on the vehicle
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
    • B60T8/17—Using electrical or electronic regulation means to control braking
    • B60T8/171—Detecting parameters used in the regulation; Measuring values used in the regulation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
    • B60T8/17—Using electrical or electronic regulation means to control braking
    • B60T8/172—Determining control parameters used in the regulation, e.g. by calculations involving measured or detected parameters
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
    • B60T8/17—Using electrical or electronic regulation means to control braking
    • B60T8/1755—Brake regulation specially adapted to control the stability of the vehicle, e.g. taking into account yaw rate or transverse acceleration in a curve
    • B60T8/17558—Brake regulation specially adapted to control the stability of the vehicle, e.g. taking into account yaw rate or transverse acceleration in a curve specially adapted for collision avoidance or collision mitigation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T2201/00—Particular use of vehicle brake systems; Special systems using also the brakes; Special software modules within the brake system controller
    • B60T2201/02—Active or adaptive cruise control system; Distance control
    • B60T2201/022—Collision avoidance systems
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T2210/00—Detection or estimation of road or environment conditions; Detection or estimation of road shapes
    • B60T2210/30—Environment conditions or position therewithin
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T2250/00—Monitoring, detecting, estimating vehicle conditions

Landscapes

  • Engineering & Computer Science (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Regulating Braking Force (AREA)

Abstract

The invention provides an automatic braking method and system for a commercial vehicle and the commercial vehicle, wherein the method comprises the following steps: acquiring external environment information of the commercial vehicle, judging whether the commercial vehicle collides at the next moment according to the external environment so as to send out a trigger signal at the pre-collision moment; monitoring the load changes of the front and rear axles of the commercial vehicle to respectively obtain the load data of the front and rear axles of the commercial vehicle; comparing the load data with the historical load in the load-braking efficiency comparison table to determine the braking efficiency of the commercial vehicle under the current load, and formulating an automatic braking strategy for avoiding collision according to the braking efficiency when receiving a trigger signal; and sending an automatic braking command to a control unit of a braking system of the commercial vehicle so that the braking system controls the commercial vehicle to automatically brake according to an automatic braking strategy. The problem that in the prior art, the braking efficiency of an automatic braking system is inconsistent due to different load conditions in the running process of a commercial vehicle, and the driving safety cannot be guaranteed is solved.

Description

Automatic braking method and system for commercial vehicle and commercial vehicle
Technical Field
The invention relates to the technical field of vehicle control, in particular to an automatic braking method and system for a commercial vehicle and the commercial vehicle.
Background
Through market research, most of the automatic braking systems on the market are loaded on passenger cars at present, and for commercial cars with large loading capacity and large load distribution influenced by loaded cargoes, special automatic braking systems are not available.
Compared with a passenger car, the commercial car has the functional characteristics of large carrying capacity and large light-load full-load distribution difference, and an automatic braking system of the passenger car is directly transplanted and converted into the commercial car, so that the problem that the braking efficiency of the automatic braking system is inconsistent due to different load conditions in the driving process of the commercial car and the driving safety cannot be guaranteed is caused.
Disclosure of Invention
Based on the above, the invention aims to provide an automatic braking method and system for a commercial vehicle and the commercial vehicle, and aims to solve the problem that in the prior art, the braking efficiency of an automatic braking system is inconsistent due to different load conditions in the running process of the commercial vehicle, and the driving safety cannot be ensured.
A first aspect of the present invention provides a method for automatically braking a commercial vehicle, the method comprising:
acquiring external environment information of the commercial vehicle in the running process of the commercial vehicle, and judging whether the commercial vehicle collides at the next moment according to the external environment so as to send out a trigger signal at the pre-collision moment;
monitoring the load changes of the front and rear axles of the commercial vehicle to respectively obtain the load data of the front and rear axles of the commercial vehicle;
comparing the load data with the historical load in a load-braking efficiency comparison table to determine the braking efficiency of the commercial vehicle under the current load, and formulating an automatic braking strategy for avoiding collision according to the braking efficiency when the trigger signal is received;
and sending an automatic braking command to a control unit of a braking system of the commercial vehicle so that the braking system controls the commercial vehicle to automatically brake according to the automatic braking strategy.
According to one aspect of the above technical solution, in a driving process of a commercial vehicle, external environment information of the commercial vehicle is obtained, and whether the commercial vehicle collides at the next moment is judged according to the external environment, so as to send out a trigger signal at a pre-collision moment, which specifically includes:
in the running process of the commercial vehicle, acquiring an external environment image through a preset first environment sensing device and acquiring an external environment obstacle signal through a preset second environment sensing device so as to obtain external environment information of the commercial vehicle;
determining the distance between the side surface of the commercial vehicle facing the obstacle and the angle of the obstacle relative to the commercial vehicle according to the external environment image and the external environment obstacle signal;
judging whether the commercial vehicle runs in the current direction according to the current speed and collides with the obstacle at the next moment according to the distance between the side surface of the commercial vehicle facing the obstacle and the angle of the obstacle relative to the commercial vehicle;
if so, a trigger signal is output at the pre-crash time.
According to an aspect of the foregoing technical solution, before the step of monitoring load changes of front and rear axles of the commercial vehicle to obtain load data of the front and rear axles of the commercial vehicle, the method includes:
acquiring historical loads of a historical commercial vehicle under different load scenes and braking efficiency under different load scenes so as to formulate a load-braking efficiency comparison table;
the method specifically comprises the steps of monitoring the load change of the front and rear axles of the commercial vehicle to respectively obtain the load data of the front and rear axles of the commercial vehicle, and comprises the following steps of:
according to the historical load, the load of the front and rear axles of the commercial vehicle is estimated to obtain a load analog signal;
and converting the load analog signal into load data in an analog-to-digital mode.
According to an aspect of the above technical solution, comparing the load data with the historical load in the load-braking effectiveness comparison table to determine the braking effectiveness of the commercial vehicle under the current load, and when the trigger signal is received, formulating an automatic braking strategy for avoiding collision according to the braking effectiveness, specifically including:
comparing the load data with a historical load in a load-braking effectiveness comparison table;
determining the braking efficiency of the commercial vehicle under the current load;
when the trigger signal is received, combining the braking efficiency with the current state of a braking system, and formulating an automatic braking strategy for avoiding collision;
the current state of the braking system is a quantized state of friction force applied by a brake pad and a brake disc in the braking system.
According to an aspect of the above technical solution, the automatic braking strategy is:
the braking cycle of the braking system corresponding to each wheel is divided into a plurality of subcycles, and the braking force generated by the braking system corresponding to each wheel in each subcycle is distributed and regulated in the plurality of subcycles of the braking cycle.
According to one aspect of the above technical solution, the step of sending an automatic braking command to a control unit of a braking system of the commercial vehicle, so that the braking system controls the commercial vehicle to brake according to the automatic braking strategy comprises:
the braking system is controlled by a PID control logic algorithm to eliminate errors by PID control after errors are generated between the control target and the automatic braking strategy.
According to an aspect of the foregoing solution, after the step of sending an automatic braking command to the control unit of the braking system of the commercial vehicle, so that the braking system controls the commercial vehicle to perform automatic braking according to the automatic braking strategy, the method further includes:
when the braking system controls the commercial vehicle to automatically brake according to the automatic braking strategy and collision with an obstacle cannot be avoided, a control instruction is sent to a control unit of an electronic hand brake system of the commercial vehicle so as to control the electronic hand brake system to automatically brake.
A second aspect of the present invention is to provide an automatic braking system for a commercial vehicle, the system comprising:
the environment monitoring module is used for acquiring external environment information of the commercial vehicle in the running process of the commercial vehicle, judging whether the commercial vehicle collides at the next moment according to the external environment so as to send out a trigger signal at the pre-collision moment;
the load monitoring module is used for monitoring the load change of the front and rear axles of the commercial vehicle so as to respectively acquire the load data of the front and rear axles of the commercial vehicle;
the strategy generation module is used for comparing the load data with the historical load in the load-braking efficiency comparison table to determine the braking efficiency of the commercial vehicle under the current load, and when the trigger signal is received, an automatic braking strategy for avoiding collision is formulated according to the braking efficiency;
and the strategy execution module is used for sending an automatic braking instruction to a control unit of the braking system of the commercial vehicle so that the braking system controls the commercial vehicle to automatically brake according to the automatic braking strategy.
According to an aspect of the foregoing technical solution, the policy generation module is specifically configured to:
comparing the load data with a historical load in a load-braking effectiveness comparison table;
determining the braking efficiency of the commercial vehicle under the current load;
when the trigger signal is received, combining the braking efficiency with the current state of a braking system, and formulating an automatic braking strategy for avoiding collision;
the current state of the braking system is a quantized state of friction force applied by a brake pad and a brake disc in the braking system.
A third aspect of the present invention provides a commercial vehicle, on which the automatic braking system for a commercial vehicle according to the above-mentioned technical solution is mounted.
Compared with the prior art, the automatic braking system and method for the commercial vehicle and the commercial vehicle have the beneficial effects that:
in the running process of the commercial vehicle, whether the commercial vehicle collides at the next moment is judged by analyzing external environment information, so that a trigger signal is sent out at the moment of pre-collision, and the load change of a front shaft and a rear shaft is monitored in time, so that the current load of the commercial vehicle is determined, the braking efficiency of the commercial vehicle under the current load can be determined, an automatic braking strategy is formulated according to the braking efficiency after the trigger signal is received, an automatic braking system is controlled to automatically brake according to the automatic braking strategy, the problem that the braking efficiency of the automatic braking system is inconsistent due to different load conditions in the running process of the commercial vehicle is solved, and the adaptability and the robustness of the automatic braking system of the commercial vehicle under different load conditions are greatly improved while the safety of a driver and passengers are ensured.
Drawings
FIG. 1 is a schematic flow chart of a method for automatically braking a commercial vehicle according to a first embodiment of the present invention;
FIG. 2 is a block diagram of a commercial vehicle automatic braking system in a third embodiment of the present invention;
the following detailed description will further illustrate the invention with reference to the above-described drawings.
Detailed Description
In order that the invention may be readily understood, a more complete description of the invention will be rendered by reference to the appended drawings. Several embodiments of the invention are presented in the figures. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.
It will be understood that when an element is referred to as being "mounted" on another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like are used herein for illustrative purposes only.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.
Example 1
Referring to fig. 1, a flowchart of a method for automatically braking a commercial vehicle according to a first embodiment of the present invention is shown, and the method includes steps S10-S40:
step S10, acquiring external environment information of the commercial vehicle in the running process of the commercial vehicle, and judging whether the commercial vehicle collides at the next moment according to the external environment so as to send out a trigger signal at the pre-collision moment;
in the driving process of the commercial vehicle, the external environment information of the commercial vehicle can be acquired through the camera, or through radar devices such as a laser radar, or through the camera and the radar devices, the external environment of the commercial vehicle can be acquired simultaneously, so that the external environment information of the commercial vehicle is generated.
The method is characterized in that a high-definition camera is arranged at the top of a vehicle head, the number of the cameras can be one or more, the placement positions are behind the front glass of the commercial vehicle, the cameras can determine the relative positions with the millimeter wave radar through software internal and external parameter calibration, and original data are provided for detecting moving and static targets on a driving road through sensing data fusion; the millimeter wave radar arranged in the front grille in front of the vehicle head can continuously emit millimeter wave frequency band radio waves to sense the front Fang Jing and dynamic objects.
In this embodiment, through the external environment information, it can be determined in which lane the commercial vehicle is currently located, whether there is an obstacle in each direction of the commercial vehicle, and the like, where the obstacle includes a fixed obstacle and a moving obstacle, so as to determine whether the commercial vehicle collides with the collision object at the next moment; for example, if the collision with the collided object is to occur after 3s without taking any avoidance measures, then a trigger signal is sent out at the moment of the collision, that is, the moment of pre-collision, and after the system receives the trigger signal, a series of avoidance measures can be taken to avoid the collision, for example, emergency steering or emergency braking is adopted.
Step S20, monitoring the load change of the front and rear axles of the commercial vehicle to respectively acquire the load data of the front and rear axles of the commercial vehicle;
in general, the load change of the commercial vehicle is caused by the difference in load, for example, the commercial vehicle has a large load.
Specifically, load data of the front and rear axles of the commercial vehicle can be obtained by monitoring load changes of the front and rear axles of the commercial vehicle. In this embodiment, the load changes of the front and rear axles are monitored by displacement sensors, one end of each displacement sensor is mounted on the frame, the other end of each displacement sensor is mounted on the axle, and each displacement sensor corresponds to one wheel, so that the deformation degree of each suspension of the front and rear axles can be determined by the displacement sensor, and the load data of the front and rear axles of the commercial vehicle can be correspondingly determined.
Step S30, comparing the load data with the historical load in a load-brake efficiency comparison table to determine the brake efficiency of the commercial vehicle under the current load, and formulating an automatic brake strategy for avoiding collision according to the brake efficiency when the trigger signal is received;
it should be noted that when two identical vehicles adopt the same braking system, the heavier the vehicle is, the longer the braking distance is, and the lower the braking efficiency is; that is, the greater the load of the commercial vehicle, the lower the braking performance thereof, and the longer the required braking distance, so that the braking operation needs to be performed in advance in the actual braking process.
The load-braking efficiency comparison table comprises the braking efficiency of the same vehicle model under different load conditions, namely the braking capacity of the same vehicle model under different load conditions; for example, commercial vehicles have an infinite braking effectiveness approaching 100% in the unloaded condition, and only 75% or less in the half-load condition, and 50% or less in the full-load condition.
In this embodiment, after the load of the front and rear axles of the commercial vehicle is monitored, the load data of the front and rear axles of the commercial vehicle is determined, and then the braking efficiency of the commercial vehicle under the current load is determined by comparing the load data with the historical load in the load-braking efficiency comparison table, and the key effect is played for the formulation of the automatic braking strategy by determining the braking efficiency of the commercial vehicle under the current load.
That is, after determining the braking effectiveness of the commercial vehicle under the current load, an automatic braking strategy for avoiding a collision is output for the braking effectiveness of the commercial vehicle after receiving the trigger signal.
For example, when the braking efficiency of the commercial vehicle is high, for example, 90%, the braking distance is short, the required braking time is short, and the braking start time can be late and the braking end time can be early in the automatic braking process; in contrast, when the braking performance of the commercial vehicle is low, the braking distance of the commercial vehicle is longer, and the required braking time is longer, that is, the braking start time is required earlier or/and the braking end time is required later, than in the case of higher braking performance.
And step S40, an automatic braking instruction is sent to a control unit of a braking system of the commercial vehicle, so that the braking system controls the commercial vehicle to automatically brake according to the automatic braking strategy.
The braking system of the commercial vehicle comprises a braking disc, a braking sheet and a hydraulic mechanism for controlling the braking sheet to contact with the braking disc, wherein the braking system is controlled by a control unit, and the control unit is used for receiving a control instruction so as to control the hydraulic mechanism to output extrusion force to the braking sheet, so that the braking sheet and the braking disc are contacted with each other, rubbed and heated to gradually consume the inertia force of the vehicle movement.
In this embodiment, after sending an automatic braking command to the control unit of the braking system of the commercial vehicle, the control unit will control the commercial vehicle to perform automatic braking according to a preset automatic braking strategy, for example, intermittent braking (i.e. spot braking) or full-scale braking to control the commercial vehicle to perform braking.
It should be noted that, what kind of automatic braking strategy is adopted by the braking system to control the commercial vehicle to automatically brake is all confirmed based on the actual load of the commercial vehicle, and of course, dynamic adjustment may also be performed based on the actual performance of the commercial vehicle in an automatic process.
Compared with the prior art, the automatic braking method for the commercial vehicle has the beneficial effects that:
in the running process of the commercial vehicle, whether the commercial vehicle collides at the next moment is judged by analyzing external environment information, so that a trigger signal is sent out at the moment of pre-collision, and the load change of a front shaft and a rear shaft is monitored in time, so that the current load of the commercial vehicle is determined, the braking efficiency of the commercial vehicle under the current load can be determined, an automatic braking strategy is formulated according to the braking efficiency after the trigger signal is received, an automatic braking system is controlled to automatically brake according to the automatic braking strategy, the problem that the braking efficiency of the automatic braking system is inconsistent due to different load conditions in the running process of the commercial vehicle is solved, and the adaptability and the robustness of the automatic braking system of the commercial vehicle under different load conditions are greatly improved while the safety of a driver and passengers are ensured.
Example two
A second embodiment of the present invention provides an automatic braking method for a commercial vehicle, which is substantially identical to the automatic braking method for a commercial vehicle shown in the first embodiment, except that:
in this embodiment, during a running process of a commercial vehicle, external environment information of the commercial vehicle is obtained, and whether the commercial vehicle collides at the next moment is judged according to the external environment, so as to send out a trigger signal at a pre-collision moment, which specifically includes:
in the running process of the commercial vehicle, acquiring an external environment image through a preset first environment sensing device and acquiring an external environment obstacle signal through a preset second environment sensing device so as to obtain external environment information of the commercial vehicle;
determining the distance between the side surface of the commercial vehicle facing the obstacle and the angle of the obstacle relative to the commercial vehicle according to the external environment image and the external environment obstacle signal;
judging whether the commercial vehicle runs in the current direction according to the current speed and collides with the obstacle at the next moment according to the distance between the side surface of the commercial vehicle facing the obstacle and the angle of the obstacle relative to the commercial vehicle;
if so, a trigger signal is output at the pre-crash time.
In this embodiment, before the step of monitoring the load changes of the front and rear axles of the commercial vehicle to obtain the load data of the front and rear axles of the commercial vehicle, the method includes:
acquiring historical loads of a historical commercial vehicle under different load scenes and braking efficiency under different load scenes so as to formulate a load-braking efficiency comparison table;
the method specifically comprises the steps of monitoring the load change of the front and rear axles of the commercial vehicle to respectively obtain the load data of the front and rear axles of the commercial vehicle, and comprises the following steps of:
according to the historical load, the load of the front and rear axles of the commercial vehicle is estimated to obtain a load analog signal;
and converting the load analog signal into load data in an analog-to-digital mode.
In this embodiment, comparing the load data with the historical load in the load-braking effectiveness comparison table to determine the braking effectiveness of the commercial vehicle under the current load, and when the trigger signal is received, formulating an automatic braking strategy for avoiding collision according to the braking effectiveness, which specifically includes:
comparing the load data with a historical load in a load-braking effectiveness comparison table;
determining the braking efficiency of the commercial vehicle under the current load;
when the trigger signal is received, combining the braking efficiency with the current state of a braking system, and formulating an automatic braking strategy for avoiding collision;
note that, the automatic braking strategy shown in this embodiment is: the braking cycle of the braking system corresponding to each wheel is divided into a plurality of subcycles, and the braking force generated by the braking system corresponding to each wheel in each subcycle is distributed and regulated in the plurality of subcycles of the braking cycle.
The current state of the braking system is a quantized state of friction force applied by a brake pad and a brake disc in the braking system.
In this embodiment, the step of sending an automatic braking command to the control unit of the braking system of the commercial vehicle, so that the braking system controls the commercial vehicle to brake according to the automatic braking strategy includes:
the braking system is controlled by a PID control logic algorithm to eliminate errors by PID control after errors are generated between the control target and the automatic braking strategy.
After the step of sending an automatic braking instruction to the control unit of the braking system of the commercial vehicle so that the braking system controls the commercial vehicle to automatically brake according to the automatic braking strategy, the method further comprises the following steps:
when the braking system controls the commercial vehicle to automatically brake according to the automatic braking strategy and collision with an obstacle cannot be avoided, a control instruction is sent to a control unit of an electronic hand brake system of the commercial vehicle so as to control the electronic hand brake system to automatically brake.
Compared with the prior art, the automatic braking method for the commercial vehicle has the beneficial effects that:
in the running process of the commercial vehicle, whether the commercial vehicle collides at the next moment is judged by analyzing external environment information, so that a trigger signal is sent out at the moment of pre-collision, and the load change of a front shaft and a rear shaft is monitored in time, so that the current load of the commercial vehicle is determined, the braking efficiency of the commercial vehicle under the current load can be determined, an automatic braking strategy is formulated according to the braking efficiency after the trigger signal is received, an automatic braking system is controlled to automatically brake according to the automatic braking strategy, the problem that the braking efficiency of the automatic braking system is inconsistent due to different load conditions in the running process of the commercial vehicle is solved, and the adaptability and the robustness of the automatic braking system of the commercial vehicle under different load conditions are greatly improved while the safety of a driver and passengers are ensured.
Example III
Referring to fig. 2, a block diagram of an automatic braking system for a commercial vehicle according to a third embodiment of the present invention is shown, the system includes: an environment monitoring module 10, a load monitoring module 20, a policy generation module 30, and a policy enforcement module 40.
The environment monitoring module 10 is configured to obtain external environment information of the commercial vehicle during a driving process of the commercial vehicle, and determine whether the commercial vehicle collides at a next moment according to the external environment, so as to send a trigger signal at a pre-collision moment;
in the driving process of the commercial vehicle, the external environment information of the commercial vehicle can be acquired through the camera, or through radar devices such as a laser radar, or through the camera and the radar devices, the external environment of the commercial vehicle can be acquired simultaneously, so that the external environment information of the commercial vehicle is generated.
The method is characterized in that a high-definition camera is arranged at the top of a vehicle head, the number of the cameras can be one or more, the placement positions are behind the front glass of the commercial vehicle, the cameras can determine the relative positions with the millimeter wave radar through software internal and external parameter calibration, and original data are provided for detecting moving and static targets on a driving road through sensing data fusion; the millimeter wave radar arranged in the front grille in front of the vehicle head can continuously emit millimeter wave frequency band radio waves to sense the front Fang Jing and dynamic objects.
In this embodiment, through the external environment information, it can be determined in which lane the commercial vehicle is currently located, whether there is an obstacle in each direction of the commercial vehicle, and the like, where the obstacle includes a fixed obstacle and a moving obstacle, so as to determine whether the commercial vehicle collides with the collision object at the next moment; for example, if the collision with the collided object is to occur after 3s without taking any avoidance measures, then a trigger signal is sent out at the moment of the collision, that is, the moment of pre-collision, and after the system receives the trigger signal, a series of avoidance measures can be taken to avoid the collision, for example, emergency steering or emergency braking is adopted.
The load monitoring module 20 is configured to monitor load changes of front and rear axles of the commercial vehicle, so as to respectively obtain load data of the front and rear axles of the commercial vehicle;
in general, the load change of the commercial vehicle is caused by the difference in load, for example, the commercial vehicle has a large load.
Specifically, load data of the front and rear axles of the commercial vehicle can be obtained by monitoring load changes of the front and rear axles of the commercial vehicle. In this embodiment, the load changes of the front and rear axles are monitored by displacement sensors, one end of each displacement sensor is mounted on the frame, the other end of each displacement sensor is mounted on the axle, and each displacement sensor corresponds to one wheel, so that the deformation degree of each suspension of the front and rear axles can be determined by the displacement sensor, and the load data of the front and rear axles of the commercial vehicle can be correspondingly determined.
The policy generation module 30 is configured to compare the load data with a historical load in a load-braking effectiveness comparison table to determine a braking effectiveness of the commercial vehicle under a current load, and when the trigger signal is received, formulate an automatic braking policy for avoiding collision according to the braking effectiveness;
it should be noted that when two identical vehicles adopt the same braking system, the heavier the vehicle is, the longer the braking distance is, and the lower the braking efficiency is; that is, the greater the load of the commercial vehicle, the lower the braking performance thereof, and the longer the required braking distance, so that the braking operation needs to be performed in advance in the actual braking process.
The load-braking efficiency comparison table comprises the braking efficiency of the same vehicle model under different load conditions, namely the braking capacity of the same vehicle model under different load conditions; for example, commercial vehicles have an infinite braking effectiveness approaching 100% in the unloaded condition, and only 75% or less in the half-load condition, and 50% or less in the full-load condition.
In this embodiment, after the load of the front and rear axles of the commercial vehicle is monitored, the load data of the front and rear axles of the commercial vehicle is determined, and then the braking efficiency of the commercial vehicle under the current load is determined by comparing the load data with the historical load in the load-braking efficiency comparison table, and the key effect is played for the formulation of the automatic braking strategy by determining the braking efficiency of the commercial vehicle under the current load.
That is, after determining the braking effectiveness of the commercial vehicle under the current load, an automatic braking strategy for avoiding a collision is output for the braking effectiveness of the commercial vehicle after receiving the trigger signal.
For example, when the braking efficiency of the commercial vehicle is high, for example, 90%, the braking distance is short, the required braking time is short, and the braking start time can be late and the braking end time can be early in the automatic braking process; in contrast, when the braking performance of the commercial vehicle is low, the braking distance of the commercial vehicle is longer, and the required braking time is longer, that is, the braking start time is required earlier or/and the braking end time is required later, than in the case of higher braking performance.
And the strategy execution module 40 is used for sending an automatic braking instruction to a control unit of the braking system of the commercial vehicle so that the braking system controls the commercial vehicle to automatically brake according to the automatic braking strategy.
The braking system of the commercial vehicle comprises a braking disc, a braking sheet and a hydraulic mechanism for controlling the braking sheet to contact with the braking disc, wherein the braking system is controlled by a control unit, and the control unit is used for receiving a control instruction so as to control the hydraulic mechanism to output extrusion force to the braking sheet, so that the braking sheet and the braking disc are contacted with each other, rubbed and heated to gradually consume the inertia force of the vehicle movement.
In this embodiment, after sending an automatic braking command to the control unit of the braking system of the commercial vehicle, the control unit will control the commercial vehicle to perform automatic braking according to a preset automatic braking strategy, for example, intermittent braking (i.e. spot braking) or full-scale braking to control the commercial vehicle to perform braking.
It should be noted that, what kind of automatic braking strategy is adopted by the braking system to control the commercial vehicle to automatically brake is all confirmed based on the actual load of the commercial vehicle, and of course, dynamic adjustment may also be performed based on the actual performance of the commercial vehicle in an automatic process.
In this embodiment, the policy generation module is specifically configured to:
comparing the load data with a historical load in a load-braking effectiveness comparison table;
determining the braking efficiency of the commercial vehicle under the current load;
when the trigger signal is received, combining the braking efficiency with the current state of a braking system, and formulating an automatic braking strategy for avoiding collision;
the current state of the braking system is a quantized state of friction force applied by a brake pad and a brake disc in the braking system.
Compared with the prior art, the commercial vehicle automatic braking system shown in the embodiment is adopted, and has the beneficial effects that:
in the running process of the commercial vehicle, whether the commercial vehicle collides at the next moment is judged by analyzing external environment information, so that a trigger signal is sent out at the moment of pre-collision, and the load change of a front shaft and a rear shaft is monitored in time, so that the current load of the commercial vehicle is determined, the braking efficiency of the commercial vehicle under the current load can be determined, an automatic braking strategy is formulated according to the braking efficiency after the trigger signal is received, an automatic braking system is controlled to automatically brake according to the automatic braking strategy, the problem that the braking efficiency of the automatic braking system is inconsistent due to different load conditions in the running process of the commercial vehicle is solved, and the adaptability and the robustness of the automatic braking system of the commercial vehicle under different load conditions are greatly improved while the safety of a driver and passengers are ensured.
Example IV
A fourth embodiment of the present invention provides a commercial vehicle equipped with the commercial vehicle automatic brake system described in the above third embodiment.
The commercial vehicle is a pickup truck, a minibus, a minivan or the like.
In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
The foregoing examples illustrate only a few embodiments of the invention and are described in detail herein without thereby limiting the scope of the invention. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the invention, which are all within the scope of the invention. Accordingly, the scope of protection of the present invention is to be determined by the appended claims.

Claims (5)

1. A method of automatically braking a commercial vehicle, the method comprising:
acquiring external environment information of the commercial vehicle in the running process of the commercial vehicle, and judging whether the commercial vehicle collides at the next moment according to the external environment so as to send out a trigger signal at the pre-collision moment;
monitoring the load changes of the front and rear axles of the commercial vehicle to respectively obtain the load data of the front and rear axles of the commercial vehicle; the load change of the front axle and the rear axle is monitored through displacement sensors, one end of each displacement sensor is arranged on the frame, the other end of each displacement sensor is arranged on the axle, and each displacement sensor corresponds to one wheel, so that the deformation degree of each suspension of the front axle and the rear axle can be determined through the displacement sensors, and the load data of the front axle and the rear axle of the commercial vehicle can be correspondingly determined;
comparing the load data with the historical load in a load-braking efficiency comparison table to determine the braking efficiency of the commercial vehicle under the current load, and formulating an automatic braking strategy for avoiding collision according to the braking efficiency when the trigger signal is received;
sending an automatic braking instruction to a control unit of a braking system of the commercial vehicle so that the braking system controls the commercial vehicle to automatically brake according to the automatic braking strategy;
wherein the automatic braking strategy is:
dividing a braking period of a braking system corresponding to each wheel into a plurality of subcycles, and distributing and adjusting braking force to be generated by the braking system corresponding to each wheel in each subcycle in the plurality of subcycles of the braking period;
when the braking system controls the commercial vehicle to automatically brake according to the automatic braking strategy and collision with an obstacle cannot be avoided, a control instruction is sent to a control unit of an electronic hand brake system of the commercial vehicle so as to control the electronic hand brake system to automatically brake;
in the running process of the commercial vehicle, acquiring external environment information of the commercial vehicle, judging whether the commercial vehicle collides at the next moment according to the external environment so as to send out a trigger signal at the pre-collision moment, wherein the method specifically comprises the following steps of:
in the running process of the commercial vehicle, acquiring an external environment image through a preset first environment sensing device and acquiring an external environment obstacle signal through a preset second environment sensing device so as to obtain external environment information of the commercial vehicle;
determining the distance between the side surface of the commercial vehicle facing the obstacle and the angle of the obstacle relative to the commercial vehicle according to the external environment image and the external environment obstacle signal;
judging whether the commercial vehicle runs in the current direction according to the current speed and collides with the obstacle at the next moment according to the distance between the side surface of the commercial vehicle facing the obstacle and the angle of the obstacle relative to the commercial vehicle;
if yes, outputting a trigger signal at the pre-collision moment;
before the step of monitoring the load change of the front and rear axles of the commercial vehicle to obtain the load data of the front and rear axles of the commercial vehicle respectively, the method comprises the following steps:
acquiring historical loads of a historical commercial vehicle under different load scenes and braking efficiency under different load scenes so as to formulate a load-braking efficiency comparison table;
the method specifically comprises the steps of monitoring the load change of the front and rear axles of the commercial vehicle to respectively obtain the load data of the front and rear axles of the commercial vehicle, and comprises the following steps of:
according to the historical load, the load of the front and rear axles of the commercial vehicle is estimated to obtain a load analog signal;
analog-to-digital converting the load analog signal into load data;
comparing the load data with a historical load in a load-braking efficiency comparison table to determine the braking efficiency of the commercial vehicle under the current load, and when the trigger signal is received, formulating an automatic braking strategy for avoiding collision according to the braking efficiency, wherein the method specifically comprises the following steps:
comparing the load data with a historical load in a load-braking effectiveness comparison table;
determining the braking efficiency of the commercial vehicle under the current load;
when the trigger signal is received, combining the braking efficiency with the current state of a braking system, and formulating an automatic braking strategy for avoiding collision;
the current state of the braking system is a quantized state of friction force applied by a brake pad and a brake disc in the braking system.
2. The automatic braking method of a commercial vehicle according to claim 1, wherein the step of transmitting an automatic braking command to a control unit of a braking system of the commercial vehicle to cause the braking system to control the commercial vehicle to brake according to the automatic braking strategy comprises:
the braking system is controlled by a PID control logic algorithm to eliminate errors by PID control after errors are generated between the control target and the automatic braking strategy.
3. A commercial vehicle automatic braking system, characterized in that the system is applied to the commercial vehicle automatic braking method according to claim 1 or 2, the system comprising:
the environment monitoring module is used for acquiring external environment information of the commercial vehicle in the running process of the commercial vehicle, judging whether the commercial vehicle collides at the next moment according to the external environment so as to send out a trigger signal at the pre-collision moment;
the load monitoring module is used for monitoring the load change of the front and rear axles of the commercial vehicle so as to respectively acquire the load data of the front and rear axles of the commercial vehicle;
the strategy generation module is used for comparing the load data with the historical load in the load-braking efficiency comparison table to determine the braking efficiency of the commercial vehicle under the current load, and when the trigger signal is received, an automatic braking strategy for avoiding collision is formulated according to the braking efficiency;
the strategy execution module is used for sending an automatic braking instruction to a control unit of a braking system of the commercial vehicle so that the braking system controls the commercial vehicle to automatically brake according to the automatic braking strategy;
wherein the automatic braking strategy is:
dividing a braking period of a braking system corresponding to each wheel into a plurality of subcycles, and distributing and adjusting braking force to be generated by the braking system corresponding to each wheel in each subcycle in the plurality of subcycles of the braking period;
and when the braking system controls the commercial vehicle to automatically brake according to the automatic braking strategy and collision with an obstacle cannot be avoided, a control instruction is sent to a control unit of an electronic hand brake system of the commercial vehicle so as to control the electronic hand brake system to automatically brake.
4. The automatic braking system of a commercial vehicle according to claim 3, wherein the strategy generation module is specifically configured to:
comparing the load data with a historical load in a load-braking effectiveness comparison table;
determining the braking efficiency of the commercial vehicle under the current load;
when the trigger signal is received, combining the braking efficiency with the current state of a braking system, and formulating an automatic braking strategy for avoiding collision;
the current state of the braking system is a quantized state of friction force applied by a brake pad and a brake disc in the braking system.
5. A commercial vehicle, characterized in that the commercial vehicle automatic brake system according to claim 3 or 4 is mounted.
CN202211012755.4A 2022-08-23 2022-08-23 Automatic braking method and system for commercial vehicle and commercial vehicle Active CN115384461B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202211012755.4A CN115384461B (en) 2022-08-23 2022-08-23 Automatic braking method and system for commercial vehicle and commercial vehicle

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202211012755.4A CN115384461B (en) 2022-08-23 2022-08-23 Automatic braking method and system for commercial vehicle and commercial vehicle

Publications (2)

Publication Number Publication Date
CN115384461A CN115384461A (en) 2022-11-25
CN115384461B true CN115384461B (en) 2024-03-01

Family

ID=84120674

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202211012755.4A Active CN115384461B (en) 2022-08-23 2022-08-23 Automatic braking method and system for commercial vehicle and commercial vehicle

Country Status (1)

Country Link
CN (1) CN115384461B (en)

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA1210707A (en) * 1984-02-14 1986-09-02 Adrian Bettenson Vehicle brake
CN102897169A (en) * 2011-07-25 2013-01-30 通用汽车环球科技运作有限责任公司 Collision avoidance maneuver through differential braking
CN107672580A (en) * 2017-09-27 2018-02-09 交通运输部公路科学研究所 A kind of the automobile long dynamic monitoring of down hill braking efficiency, warning system and method
CN110422151A (en) * 2019-07-18 2019-11-08 浙江吉利新能源商用车集团有限公司 A kind of vehicle auxiliary braking method, device, system and terminal
CN110525429A (en) * 2019-08-31 2019-12-03 武汉理工大学 A kind of commercial vehicle emergency braking method based on V2X
CN111252066A (en) * 2020-01-19 2020-06-09 一汽解放汽车有限公司 Emergency braking control method and device, vehicle and storage medium
CA3119616A1 (en) * 2020-06-04 2021-12-04 Caterpillar Underground Mining Pty. Ltd. Method and control system for controlling machine
CN114604209A (en) * 2022-03-17 2022-06-10 西安法士特汽车传动有限公司 VCU emergency braking auxiliary control system and method for pure electric commercial vehicle
CN114889635A (en) * 2022-03-29 2022-08-12 徐州徐工汽车制造有限公司 Vehicle automatic driving control system, method, commercial vehicle and storage medium

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA1210707A (en) * 1984-02-14 1986-09-02 Adrian Bettenson Vehicle brake
CN102897169A (en) * 2011-07-25 2013-01-30 通用汽车环球科技运作有限责任公司 Collision avoidance maneuver through differential braking
CN107672580A (en) * 2017-09-27 2018-02-09 交通运输部公路科学研究所 A kind of the automobile long dynamic monitoring of down hill braking efficiency, warning system and method
CN110422151A (en) * 2019-07-18 2019-11-08 浙江吉利新能源商用车集团有限公司 A kind of vehicle auxiliary braking method, device, system and terminal
CN110525429A (en) * 2019-08-31 2019-12-03 武汉理工大学 A kind of commercial vehicle emergency braking method based on V2X
CN111252066A (en) * 2020-01-19 2020-06-09 一汽解放汽车有限公司 Emergency braking control method and device, vehicle and storage medium
CA3119616A1 (en) * 2020-06-04 2021-12-04 Caterpillar Underground Mining Pty. Ltd. Method and control system for controlling machine
CN114604209A (en) * 2022-03-17 2022-06-10 西安法士特汽车传动有限公司 VCU emergency braking auxiliary control system and method for pure electric commercial vehicle
CN114889635A (en) * 2022-03-29 2022-08-12 徐州徐工汽车制造有限公司 Vehicle automatic driving control system, method, commercial vehicle and storage medium

Also Published As

Publication number Publication date
CN115384461A (en) 2022-11-25

Similar Documents

Publication Publication Date Title
CN110155046B (en) Automatic emergency braking hierarchical control method and system
JP4878945B2 (en) Automatic braking control device
US9180881B2 (en) Braking control system and method for vehicle
CN1255294C (en) Seat belt device and seat belt device control method
US10589740B2 (en) Automated collision mitigation system of a vehicle and method thereof
US20060155469A1 (en) Crash-safe vehicle control system
US20100194593A1 (en) Neural network for intelligent transportation systems
JP2000099899A (en) Method and system for finding optimum vehicle travel interval distance
WO2007023666A1 (en) Automatic brake control device
CN1498803A (en) Vehicle braking controller
CN103547940A (en) Monitoring apparatus and method
SE538252C2 (en) Procedure and systems for safety improvement when driving a motor vehicle
US20220415180A1 (en) Operation of a vehicle platoon with a plurality of motor vehicles
JP4869792B2 (en) Automatic braking control device
CN115384461B (en) Automatic braking method and system for commercial vehicle and commercial vehicle
US11890939B2 (en) Driver assistance system
CN114038238A (en) Collision early warning system and method based on driving state of second vehicle in front
JP2021509376A (en) A system and method for determining when an object detected by an anti-collision sensor on one vehicle body of an articulated vehicle includes another vehicle body of the vehicle.
CN116279341B (en) Safety braking method and device, electronic equipment and storage medium
US20220194372A1 (en) Vehicle control system and vehicle control method
JP4869791B2 (en) Automatic braking control device
JP2007196901A (en) Automatic braking control device
JP2007210594A (en) Automatic braking control device
CN115639562B (en) Commercial vehicle blind spot detection system, braking method, commercial vehicle and storage medium
AU2021456002A1 (en) A method for controlling a maximum allowed speed of an autonomous vehicle

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant