KR102582456B1 - Brake control apparatus and control method of brake apparatus - Google Patents

Abstract

A braking control device installed in a vehicle including a wheel includes a braking unit that applies braking torque to the wheel; and a control unit electrically connected to the brake unit, wherein the control unit controls the brake unit to apply braking torque to the wheel based on the position of the brake pedal, and controls the brake unit to apply braking torque to the wheel while the vehicle is traveling on an incline. The braking unit may be controlled to generate a braking torque that is smaller than the driving torque of the engine and larger than the minimum braking torque of the slope.

Description

Braking control device and control method of the braking device {BRAKE CONTROL APPARATUS AND CONTROL METHOD OF BRAKE APPARATUS}

The disclosed invention relates to a braking control device and a method of controlling a braking device, and more particularly, to a braking control device and a method of controlling a braking device including a traction control system (TCS).

Vehicles are essentially equipped with a braking device to perform braking, and braking control devices that control the braking device in various ways have been proposed for the safety of drivers and passengers.

Recently, vehicles are equipped with traction control (TCS) to improve traction. Traction control controls the drive torque provided to the wheel to prevent wheel spin (or slip).

The vehicle's braking control device is equipped with a Brake Traction Control System (BTCS) to improve the vehicle's traction. Braking traction control can apply braking torque to the wheel to prevent left and right asymmetric spin of the wheel due to uneven friction coefficient (Split mu) of the road surface.

However, despite conventional traction control, a roll-back phenomenon in which the vehicle is pushed backward may still occur when the vehicle is driven on a slope at low speed.

For the above reasons, one aspect of the disclosed invention seeks to provide a braking control device and a method of controlling the braking device that can prevent rollback when driving on a slope at low speed.

According to one aspect of the disclosed invention, a braking control device installed in a vehicle including a wheel includes: a braking unit that applies braking torque to the wheel; and a control unit electrically connected to the brake unit, wherein the control unit controls the brake unit to apply braking torque to the wheel based on the position of the brake pedal, and controls the brake unit to apply braking torque to the wheel while the vehicle is traveling on an incline. The braking unit may be controlled to generate a braking torque that is smaller than the driving torque of the engine and larger than the minimum braking torque of the slope.

According to one aspect of the disclosed invention, a method of controlling a braking device installed in a vehicle including a wheel includes applying braking torque to the wheel based on the position of a brake pedal of the vehicle; This may include generating a braking torque that is smaller than the driving torque of the engine of the vehicle and greater than the minimum braking torque of the incline while the vehicle is traveling on an incline.

According to one aspect of the disclosed invention, a braking control device including a wheel and a wheel cylinder corresponding to the wheel includes: a piston pump supplying hydraulic pressure to the wheel cylinder to apply braking torque to the wheel; a drive motor that drives the piston pump; a flow path extending from the piston pump to the wheel cylinder; At least one valve opening the flow path; and a control unit electrically connected to the drive motor and the at least one valve, wherein the control unit determines the driving torque when the driving torque of the engine of the vehicle is greater than the minimum braking torque of the slope while the vehicle is traveling on the slope. Control at least one of the drive motor and the at least one valve to generate a braking torque substantially equal to the minimum braking torque if the driving torque is less than the minimum braking torque while the vehicle is traveling on an incline. At least one of the driving motor and the at least one valve may be controlled to generate the same braking torque.

According to one aspect of the disclosed invention, a braking control device and a method of controlling the braking device that can prevent rollback when driving on a slope at low speed can be provided.

Thereby, the brake control device and the braking method of the vehicle can prevent the vehicle from rolling back and allow the vehicle to climb the incline even if the driver slightly depresses the accelerator pedal while the brake traction control is activated on the incline.

1 shows a drive system and a braking system included in a vehicle according to one embodiment.
2 shows a hydraulic circuit of a braking control device according to one embodiment.
Figure 3 shows a control block of a braking control device according to one embodiment.
Figure 4 is a diagram for calculating the minimum braking torque for braking a vehicle according to one embodiment.
Figure 5 shows changes in driving torque and braking torque of a vehicle according to one embodiment.
Figure 6 shows the operation of a braking control device according to one embodiment.

Like reference numerals refer to like elements throughout the specification. This specification does not describe all elements of the embodiments, and general content or overlapping content between the embodiments in the technical field to which the disclosed invention pertains is omitted. The term 'unit, module, member, block' used in the specification may be implemented as software or hardware, and depending on the embodiment, a plurality of 'unit, module, member, block' may be implemented as a single component, or It is also possible for one 'part, module, member, or block' to include multiple components.

Throughout the specification, when a part is said to be “connected” to another part, this includes not only direct connection but also indirect connection, and indirect connection includes connection through a wireless communication network. do.

Additionally, when a part "includes" a certain component, this means that it may further include other components rather than excluding other components, unless specifically stated to the contrary.

Throughout the specification, when a member is said to be located “on” another member, this includes not only cases where a member is in contact with another member, but also cases where another member exists between the two members.

Terms such as first and second are used to distinguish one component from another component, and the components are not limited by the above-mentioned terms.

Singular expressions include plural expressions unless the context clearly makes an exception.

The identification code for each step is used for convenience of explanation. The identification code does not explain the order of each step, and each step may be performed differently from the specified order unless a specific order is clearly stated in the context. there is.

Hereinafter, the operating principle and embodiments of the disclosed invention will be described with reference to the attached drawings.

1 shows a drive system and a braking system included in a vehicle according to one embodiment.

The vehicle 1 includes a body that forms its exterior and accommodates the driver and/or luggage, a chassis that includes component parts of the vehicle 1 other than the body, and on which the vehicle 1 can move. It includes a wheel (2) that rotates so that the

Referring to FIG. 1 , vehicle 1 includes a drive system 10 and a braking system 40 .

The drive system 10 generates driving torque for driving the vehicle 1 and includes an engine 11, an engine control module 12, and a transmission 21.

The engine 11 includes a cylinder and a piston and can generate driving torque for the vehicle 1 to run. The transmission 21 includes a plurality of gears and can transmit the driving torque generated by the engine 11 to the wheels. In particular, the transmission 21 includes a differential gear that allows the left and right wheels to rotate at different rotational speeds due to the driving torque of the engine 11.

The engine control module 12 is an electronic control unit (Electronic Control Control Unit) for controlling the rotation speed (rpm, revolution per minute) and/or driving torque of the engine 11 in response to the driver's intention to accelerate through the accelerator pedal 11a. Unit, ECU).

The braking system 40 generates braking torque to stop the vehicle 1 and includes a braking device 41 and a braking control module (Electronic Brake Control Module, EBCM) 100.

The braking device 41 may include a brake caliper 42 installed on the wheel 2 of the vehicle 1, as shown in FIG. 1. The brake caliper 42 includes a pair of brake pads provided on both sides of the brake disc 43 connected to the wheel 2. The brake caliper 42 can press the brake disc 43 on both sides of the brake disc 43 by fluid pressure or mechanical pressure. Due to friction between the brake pad of the brake caliper 42 and the brake disc 43, the rotation of the brake disc 43 and the wheel 2 may be stopped.

In addition, the brake caliper 42 receives a pressurized medium (e.g., brake oil) from the braking control device 100, and the brake pad is pressed against the brake disc by the pressure of the pressurized medium (hereinafter referred to as “hydraulic pressure”). It may include wheel cylinders 44a, 44b (see FIG. 2), which are brought into contact.

The braking control device wheel 2 is provided with a wheel speed sensor 180 that detects the rotational speed of the wheel 2.

The braking control device 100 may include a hydraulic circuit for supplying hydraulic pressure to the wheel cylinder in response to the driver's intention to brake through the brake pedal 101, and an electronic control unit for controlling the hydraulic circuit.

The braking control device 100 may control the hydraulic pressure supplied to the wheel cylinder of the braking device 41 to temporarily release the braking of the wheel in response to the slip of the wheel 2 when braking the vehicle 1 ( Anti-lock Braking Systems (ABS).

The brake control device 100 supplies wheel cylinders of the brake device 42 to selectively brake the wheels 2 in response to oversteering and/or understeering when steering the vehicle 1. The hydraulic pressure can be controlled (electronic stability control, ESC).

Additionally, the braking control device 100 may control the rotation of the wheel 2 in response to the spin of the wheel 2 when the vehicle 1 is driven. For example, in response to the spin of the wheel 2 detected when the vehicle 1 is starting, the brake control device 100 may apply the wheel cylinder of the brake device 42 to temporarily brake the wheel 2. The supplied hydraulic pressure can be controlled. In response to the spin of the wheel 2 detected while the vehicle 1 is running, the braking control device 100 may control the engine control module 12 to reduce the torque of the engine 11, and may also control the wheel The hydraulic pressure supplied to the wheel cylinder of the braking device 42 can be controlled to temporarily brake (2).

The driving system 10 and braking system 40 may communicate with each other through a vehicle communication network. For example, electrical components transmit data through Ethernet, MOST (Media Oriented Systems Transport), Flexray, CAN (Controller Area Network), LIN (Local Interconnect Network), etc. You can give and receive.

For example, the engine control module 12 may transmit the rotation speed of the engine 11, the driving torque of the engine 11, the displacement of the accelerator pedal 11a, etc. through a communication network.

The braking control device 100 receives data including the rotation speed of the engine 11, the driving torque of the engine 11, the displacement of the accelerator pedal 11a, the gear position of the transmission 21, etc. through a communication network. , the braking device 41 can be controlled based on the received data.

For example, while the vehicle 1 is stopped on an incline, the driver can change the shift lever from the parking position (P) to the driving position (D). When the driver takes his or her foot off the brake pedal 101 to press the accelerator pedal 11a, the vehicle 1 may be pushed back by gravity. To prevent this, the braking control device 100 sets the brake pedal 101 to the reference position (when the vehicle 1 is stopped on an incline and the gear position of the transmission 21 is the driving position D). The braking device 42 can still be controlled to brake the vehicle 1 even if the brake pedal is moved to the position of the brake pedal when the foot is released from . (hereinafter referred to as Hill Start Assist, HSA)

Figure 2 shows a hydraulic circuit of a braking control device according to one embodiment.

Referring to Figure 2, the brake control system vehicle 1 is provided with a brake pedal 101 that accepts the driver's intention to brake. The braking control device 100 includes a reservoir 103 that stores pressurized media (e.g., brake oil, etc.), a master cylinder 104 that generates hydraulic pressure by moving the brake pedal 101, and a brake pedal ( A piston pump 160 that generates hydraulic pressure in response to detecting the movement of 101), a drive motor 150 that drives the piston pump 160, and a master cylinder 104 and/or piston pump 160. It includes a hydraulic circuit 110 connected to the wheel cylinders 44a and 44b.

The piston pump 160 includes a cylinder 161 and a piston 162, and the internal space of the cylinder 161 is divided into a first pressure chamber 161a and a second pressure chamber 161b by the piston 162. It can be.

The piston pump 160 may generate hydraulic pressure by moving the piston 162 in response to the movement of the brake pedal 101. A brake pedal sensor 130 that detects movement of the brake pedal 101 may be provided, and the piston 162 of the piston pump 160 may move based on the output of the brake pedal sensor 130.

The drive motor 150 may generate rotational force to move the piston 162. The rotational force of the drive motor 150 is converted into reciprocating motion force through a power transmission unit (eg, a plurality of gears), and the piston 162 can reciprocate by the reciprocating force converted from the power transmission unit.

The hydraulic circuit 110 hydraulically connects the piston pump 160 to the wheel cylinders 44a and 44b, and can transmit or block the hydraulic pressure generated by the piston pump 160 to the wheel cylinders 44a and 44b.

The hydraulic circuit 110 includes a main flow path 111 connecting the piston pump 160 to the wheel cylinders 44a and 44b, and also includes a hydraulic pressure control unit 117 on the main flow path 111 and inlet valves ( 113a, 113b) and outlet valves 114a, 114b are provided.

The hydraulic control unit 117 may be hydraulically connected to the first pressure chamber 161a and the second pressure chamber 161b of the piston pump 160 and may include a plurality of valves. The hydraulic pressure control unit 117 may guide the hydraulic pressure generated by the piston pump 160 to the wheel cylinders 44a and 44b. For example, the hydraulic pressure control unit 117 may guide the hydraulic pressure generated in the first pressure chamber 161a to the wheel cylinders 44a and 44b while the piston 162 advances, and the piston 162 During this backward movement, the hydraulic pressure generated in the second pressure chamber 161b can be guided to the wheel cylinders 44a and 44b.

In the hydraulic control unit 117, the main flow path 111 is branched into a first main flow path 111a and a second main unit 111b, and the first main flow path 111a is connected to the first wheel 2a. It extends to the first wheel cylinder 44a, and the second main flow path 111b extends to the second wheel shield 44b associated with the second wheel 2b. Here, the first wheel 2a and the second wheel 2b may be wheels provided on the left and right sides of the vehicle 1, respectively. For example, the first wheel 2a may be a left front wheel or a left rear wheel, and the second wheel 2b may be a right front wheel or a right rear wheel.

Inlet valves 113a and 113b and outlet valves 114a and 114b may be provided in each of the first main passage 111a and the second main unit 111b.

The inlet valves 113a and 113b are disposed on the main flow paths 111a and 111b connecting the piston pump 160 with the wheel cylinders 44a and 44b. A first inlet valve 113a may be provided in the first main flow passage 111a, and a second inlet valve 113b may be provided in the second main unit 111b. The inlet valves 113a and 113b may allow or block hydraulic pressure transmitted from the piston pump 160 to the wheel cylinders 44a and 44b. The inlet valves 113a and 113b may be normally open solenoid valves.

The outlet valves 114a and 114b are disposed on the flow path connecting the wheel cylinders 44a and 44b with the reservoir 103. A first outlet valve 114a is provided on the flow path connecting the first wheel cylinder 44a with the reservoir 103, and a second outlet is provided on the flow path connecting the second wheel cylinder 44b with the reservoir 103. A valve 114b is provided. The outlet valves 114a and 114b may allow or block the hydraulic pressure of the wheel cylinders 44a and 44b from being discharged to the reservoir 103. The outlet valves 114a and 114b may be normally closed solenoid valves.

The hydraulic circuit 110 further includes an auxiliary passage 112 connecting the master cylinder 104 to the wheel cylinder 44a and a cut valve 118 provided on the auxiliary passage 112.

The cut valve 118 may prevent the hydraulic pressure of the master cylinder 104 from being provided to the wheel cylinder 44a. In other words, the cut valve 118 may block the hydraulic pressure of the master cylinder 104 and allow the hydraulic pressure of the piston pump 160 to be provided to the wheel cylinders 44a and 44b.

If the piston pump 160 is malfunctioning or out of control, the cut valve 118 may be opened, and the opening of the cut valve 118 may allow hydraulic pressure from the master cylinder 104 to be provided to the wheel cylinder. there is. The cut valve 118 may be a normally open solenoid valve that is normally open to allow connection of the piston pump 160 and the wheel cylinders 44a and 44b when power is lost.

The hydraulic circuit 110 further includes check valves installed at appropriate flow path positions to prevent reverse flow of brake oil. The valves included in the braking control device 100, such as the inlet valves 113a and 113b, the outlet valves 114a and 114b, the hydraulic control unit 117, the cut valve 118, and the check valve, are integrated into the valve block. can be formed.

The braking control device 100 may further include a pressure sensor 140 that measures the hydraulic pressure of the hydraulic circuit 110.

When the driver steps on the brake pedal 101, the piston pump 160 can supply hydraulic pressure to the wheel cylinders 44a and 44b through the hydraulic pressure control unit 117 and the inlet valves 113a and 113b.

Additionally, the braking control device 100 may generate and control hydraulic pressure to realize the previously described ABS and/or ESC and/or BTCS. Additionally, the braking control device 100 may close the inlet valves 113a and 113b and maintain the hydraulic pressure of the wheel cylinders 44a and 44b to provide HSA.

Figure 3 shows a control block of a braking control device according to one embodiment. Figure 4 is a diagram for calculating the minimum braking torque for braking a vehicle according to one embodiment.

As shown in FIG. 3, the brake control device vehicle 1 includes a brake pedal sensor 130 that detects the movement of the brake pedal 101 and a wheel speed sensor 180 that detects the rotational speed of the wheel 2. A motion sensor 190 that detects the movement of the vehicle 1 is provided. The braking control device 100 includes a pressure sensor 140 that detects the pressure in the hydraulic circuit 110, a piston pump 160 that generates hydraulic pressure to supply to the wheel cylinders 44a and 44b, and a piston pump 160. ), a drive motor 150 that drives the piston pump 160, a valve block 170 that opens or closes a passage that guides the hydraulic pressure generated by the piston pump 160 to the wheel cylinders 44a and 44b, and a braking control device 100. ) includes a control unit 120 that controls the operation of.

The brake pedal sensor 130 can detect the moving distance and/or moving speed at which the brake pedal 101 moves according to the driver's intention to brake, and generates an electrical output signal ( A pedal signal) may be provided to the control unit 120. The control unit 120 may determine the driver's intention to brake depending on the pedal signal from the brake pedal sensor 130.

The pressure sensor 140 is provided on the hydraulic circuit 110 that provides hydraulic pressure to the wheel cylinders 44a and 44b, and can detect the hydraulic pressure of the pressurized medium on the hydraulic circuit 110. The pressure sensor 140 may provide the control unit 120 with an electrical output signal (pressure signal) depending on the sensed hydraulic pressure. The control unit 120 may determine the hydraulic pressure generated by the master cylinder 104 and/or the piston pump 160 depending on the pressure signal from the pressure sensor 140.

The location and number of pressure sensors 140 are not limited. For example, the pressure sensor 140 may be provided at a location capable of detecting hydraulic pressure generated by the master cylinder 104 and/or the piston pump 160. Additionally, a sufficient pressure sensor 140 may be provided to detect the hydraulic pressure generated by the master cylinder 104 and/or the piston pump 160.

The wheel speed sensor 180 can detect the rotational speed of the wheel 2 provided in the vehicle 1. The wheel speed sensor 180 is installed on each of a plurality of wheels (eg, four wheels) and can detect the rotation speed of each of the plurality of wheels. For example, the wheel 2 of the vehicle 1 may be provided with a tooth-shaped ring with a plurality of metal poles formed on the outer peripheral surface, and the wheel speed sensor 180 includes a bar-shaped permanent magnet and a coil wound around the permanent magnet. may include. The vane speed sensor 180 is provided around the tooth-shaped ring so that the pole (N-pole or S-pole) of the permanent magnet faces the tooth-shaped ring of the wheel 2. The rotation of the tooth-shaped ring due to the rotation of the wheel 2 causes a change in the magnetic field around the permanent magnet, and the coil of the wheel speed sensor 180 produces an electrical signal (alternating current signal) corresponding to the change in the magnetic field around the permanent magnet. can be transmitted to the control unit 120. The control unit 120 may identify the rotation speed of the wheel 2 based on the electrical signal from the wheel speed sensor 180.

The motion sensor 190 may detect the movement of the vehicle 1, including the linear acceleration and rotational acceleration of the vehicle 1, and provide an electrical signal corresponding to the movement of the vehicle 1 to the control unit 120. . For example, the motion sensor 190 may detect the vertical acceleration, longitudinal acceleration, and lateral acceleration of the vehicle 1 based on changes in the gravitational acceleration acting on the vehicle 1. Additionally, the motion sensor 190 may detect the yaw rate, roll rate, and pitch rate of the vehicle 1 using rotational inertia or Coriolis force.

The piston pump 160 may generate hydraulic pressure by receiving rotational force from the drive motor 150. The piston pump 160 includes, for example, a cylinder 161 and a piston 162, and can generate hydraulic pressure by moving the piston 162 due to rotation of the drive motor 150.

The drive motor 150 may generate rotational force in response to a drive signal from the control unit 120. Rotational force generated by the drive motor 150 may be provided to the piston pump 160. The driving motor 150 may include, for example, a brushless direct current motor (BLDC motor), a permanent magnet synchronous motor (PMSM), a direct current motor, or an induction motor.

The valve block 170 may include a plurality of valves of the braking control device 100. For example, the valve block 170 may include inlet valves 113a, 113b, outlet valves 114a, 114b, hydraulic pressure control unit 117, and cut valve 118 shown in FIG. 2. .

The valve block 170 may open or close a passage included in the hydraulic circuit 110 in response to a control signal (open signal or close signal) from the controller 120. For example, the valve block 170 provides a flow path that guides hydraulic pressure from the master cylinder 104 to the wheel cylinders 44a and 44b, as shown in FIG. 2, or directs hydraulic pressure to the piston as shown in FIG. 2. A flow path guiding from the pump 160 to the wheel cylinders 44a and 44b may be provided.

The control unit 120 includes an output signal (pedal signal) of the brake pedal sensor 130, an output signal (pressure signal) of the pressure sensor 140, an output signal (wheel speed signal) of the wheel speed sensor 180, and a motion sensor ( The driving motor 150 and the valve block 170 can be controlled based on the output signal (motion signal) of 190). In addition, the control unit 120 can obtain data related to the driving of the vehicle 1 from the engine control module 12 through a vehicle communication network, and the drive motor 150 based on the data related to the driving of the vehicle 1 ) and valve block 170 can be controlled.

The control unit 120 may include a plurality of semiconductor devices and may be called variously, such as ECU (Electronic Control Unit). The control unit 120 includes a CAN transceiver 123, a memory 122, and a processor 121. The CAN transceiver 123, memory 122, and processor 121 may each be implemented as separate semiconductor devices, or may be implemented as a single semiconductor device. The control unit 120 may include a plurality of processors and/or a plurality of memories.

The CAN transceiver 123 may receive data related to the driving of the vehicle 1 from the engine control module 12 through a vehicle communication network. For example, the can transceiver 123 may receive data including the displacement of the accelerator pedal 11a and the driving torque of the engine 11 from the engine control module 12, and may send the received data to the processor 121. ) can be passed on.

The memory 122 can remember/store programs and data for braking the vehicle 1 depending on the driver's will to brake. For example, the memory 122 stores programs and data for controlling the drive motor 150 and the valve block 170 to provide hydraulic pressure to the wheel cylinders 44a and 44b depending on the driver's intention to brake. You can save it. In addition, the memory 122 includes a drive motor 150 and a valve block ( 170) can remember/save programs and data that control it.

The memory 122 may provide programs and data to the processor 121 and store temporary data generated during the operation of the processor 121.

The memory 122 includes volatile memories such as Static Random Access Memory (S-RAM) and Dynamic Random Access Memory (D-RAM), Read Only Memory (ROM), and Epi-ROM ( It may include non-volatile memory such as Erasable Programmable Read Only Memory (EPROM) and flash memory. The memory 122 may include one semiconductor device or a plurality of semiconductor devices.

The processor 121 may provide control signals to the driving motor 150 and the valve block 170 according to the program and data provided from the memory 122. For example, the processor 121 may provide a drive signal for generating hydraulic pressure to the drive motor 150, and provide an opening/closing signal for guiding the hydraulic pressure from the piston pump 160 to the wheel cylinders 44a and 44b. It can be provided to the valve block 170.

The processor 121 may include an operation circuit, a memory circuit, and a control circuit. The processor 121 may include one semiconductor device or a plurality of semiconductors. Additionally, the processor 121 may include one core or a plurality of cores within one semiconductor device. This processor 121 may be called variously, such as MPU (Micro Processing Unit).

In this way, the control unit 120 may control the drive motor 150 and/or the valve block 170 to brake the vehicle 1 depending on the output signal output from the brake pedal sensor 130.

The vehicle (1) is stopped on a slope, the gear position of the transmission (21) is changed from the parking position (P) to the driving position (D), and the brake pedal 101 is set to the reference position (brake when the driver takes his foot off the brake pedal) When moving to the pedal position, the control unit 120 may control the drive motor 150 and/or the valve block 170 to maintain braking of the vehicle 1. In other words, the HSA function of the braking control device 100 is engaged on a slope.

Wheel spin (slip) may occur while the vehicle 1 is starting or driving on a road with a low coefficient of friction. For example, spin may occur in the drive wheel (wheel driven by the drive system), and the vehicle 1 may not move forward and may slip due to wheel spin.

Additionally, wheel spin (slip) may occur while the vehicle 1 is starting or driving on a road with an uneven coefficient of friction (split-mu). For example, spin may occur in either the left or right drive wheel. When spin occurs in the wheel, the driving torque of the engine 11 may be biased and provided to the wheel in which the spin occurred due to the differential gear. As a result, the vehicle 1 may not move forward and may slip on the road.

The braking control device 100 can control the spin of the wheels to improve traction (the force with which the vehicle wants to move) on a road surface with a low friction coefficient or a road surface with an uneven friction coefficient. The control unit 120 may detect the spin of the wheel 2 based on the difference in rotation speed between the wheels (for example, the difference in rotation speed between the driving wheel and the driven wheel). When detecting wheel spin greater than the target spin, the control unit 120 may control the driving torque and braking torque so that the wheel spin is smaller than the target spin. For example, the control unit 120 may provide a message to the engine control module 12 to reduce the driving torque of the engine 11, and may apply braking to the wheel in order to reduce the rotation speed of the wheel for which spin is detected. Braking torque can be applied. In particular, when the spin of either the left wheel or the right wheel is detected, the control unit 120 may apply braking torque to the wheel for which spin was detected to balance the driving torque of the left wheel and the right wheel.

The control unit 120 may control the drive motor 150 and/or the valve block 170 to prevent the vehicle 1 from rolling back due to a lack of driving torque while the vehicle 1 is traveling at a low speed on an incline. . For example, if the driver presses the accelerator pedal 11a weaker or takes his or her foot off the accelerator pedal 11a while the vehicle 1 is driving at a low speed on an incline, the vehicle 1 may move backwards due to the acceleration of gravity. there is. To prevent this, when the vehicle 1 is traveling at a low speed on an incline, the braking control device 100 may generate braking torque to prevent the vehicle 1 from rolling back. In other words, the BTCS function of the braking control device 100 may be intervened while the vehicle 1 is driving on an incline.

Specifically, the control unit 120 may identify whether the vehicle 1 is located on a ramp and the degree of inclination of the ramp based on the output signal of the motion sensor 190. For example, the control unit 120 may identify whether the slope of the ramp is 10% or more. The slope of the ramp is defined as 0% for the slope of the road perpendicular to the direction of gravitational acceleration, 100% for the slope of the road parallel to the direction of gravitational acceleration, and can be expressed as a percentage between vertical and parallel. .

The control unit 120 may identify whether the slope of the ramp on which the vehicle 1 is located is greater than or equal to a predetermined slope. For example, the control unit 120 may identify whether the slope of the ramp is 10% or more.

The control unit 120 may determine the speed of the vehicle (hereinafter referred to as “vehicle speed”) based on the output signal of the wheel speed sensor 180. For example, the control unit 120 may determine the vehicle speed based on the rotational speed of the driven wheel and identify whether the vehicle speed is less than a predetermined reference speed. For example, the control unit 120 may identify whether the vehicle speed is less than 5 Kph (Km per hour).

The control unit 120 may determine the displacement of the accelerator pedal 11a based on communication data from the engine control module 12. The control unit 120 may identify whether the displacement of the accelerator pedal 11a is greater than a predetermined reference displacement.

The control unit 120 may determine the spin of the wheel based on the output signal of the wheel speed sensor 180. For example, the control unit 120 may determine the spin of the wheel based on the difference between the rotation speed of the driving wheel and the rotation speed of the driven wheel, and may identify whether the spin of the wheel is less than a predetermined reference spin. there is. For example, the control unit 120 may identify whether the wheel spin is less than 1 Kph.

If the slope of the ramp is less than the standard slope, the vehicle speed is greater than the standard speed, the displacement of the accelerator pedal 11a is less than the standard displacement, or the spin of the wheel is greater than the standard spin, the controller 120 performs braking traction control. Braking torque can be determined based on wheel spin. The control unit 120 may control the driving motor 150 and the valve block 170 to provide hydraulic pressure corresponding to the determined braking torque to the wheel cylinders 44a and 44b.

If the slope of the ramp is greater than the standard slope, the vehicle speed is less than the standard speed, the displacement of the accelerator pedal 11a is greater than the standard displacement, and the spin of the wheel is less than the standard spin, the control unit 120 prevents the vehicle 1 from rolling back. Braking torque can be varied.

The control unit 120 may determine the driving torque of the engine 11 based on communication data from the engine control module 12. The controller 120 may identify whether the braking torque according to the braking traction control is smaller than the driving torque of the engine 11.

If the braking torque according to the braking traction control is not less than the driving torque of the engine 11, the control unit 120 may control the braking control device 100 to generate the same braking torque as the driving torque of the engine 11. In other words, the control unit 120 may control the drive motor 150 and the valve block 170 to provide hydraulic pressure corresponding to the driving torque of the engine 11 to the wheel cylinders 44a and 44b.

If the braking torque according to the brake traction control is less than the driving torque of the engine 11, the control unit 120 may identify whether the braking torque according to the brake traction control is more than the minimum braking torque that does not roll back on the slope.

The controller 120 may determine the minimum braking torque that does not cause rollback on an incline. For example, as shown in FIG. 4 , a driving resistance force (F_grade_resistance) due to the slope may act on the vehicle 1 on a slope. The control unit 120 may determine the minimum braking torque based on the driving resistance due to the incline (F_grade_resistance).

For example, driving resistance due to incline (F_grade_resistance) can be calculated by [Equation 1].

[Equation 1]

Here, F_grade_resistance represents the driving resistance, M_veh represents the mass of the vehicle 1, g represents the gravitational acceleration, α_gr represents the slope of the ramp, and sin() may represent a sine function. The mass of the vehicle 1 can be defined in advance, the gravitational acceleration is a constant, and the slope of the ramp can be calculated from the output of the motion sensor 190.

The minimum braking torque can be calculated by [Equation 2].

[Equation 2]

Here, T represents the minimum braking torque, and Rtire_radius represents the dynamic radius of the wheel (2). The dynamic radius of the wheel 2 may represent the distance between the rotation axis of the wheel 2 and the ground while the vehicle 1 is running, and may be defined in advance.

The controller 120 may compare the braking torque according to the braking traction control with the minimum braking torque on the slope and determine whether the braking torque according to the braking traction control is greater than or equal to the maximum braking torque.

If the braking torque according to the braking traction control is less than the minimum braking torque for the slope, the controller 120 may control the braking control device 100 to generate a braking torque equal to the minimum braking torque for the slope. In other words, the control unit 120 may control the drive motor 150 and the valve block 170 to provide hydraulic pressure corresponding to the minimum braking torque on the slope to the wheel cylinders 44a and 44b.

If the braking torque according to the braking traction control is more than the minimum braking torque for the slope, the control unit 120 may control the braking control device 100 to maintain the braking torque according to the braking traction control. In other words, the control unit 120 may control the drive motor 150 and the valve block 170 to provide hydraulic pressure corresponding to the braking torque according to braking traction control to the wheel cylinders 44a and 44b.

In this way, the control unit 120 can control the braking control device 100 to generate braking torque to prevent rollback during low-speed driving on an incline.

Specifically, the control unit 120 determines the driving torque of the engine 11 and the minimum braking torque on the slope, and identifies whether the driving torque of the engine 11 is greater than or equal to the minimum braking torque on the slope. If the driving torque of the engine 11 is greater than the minimum braking torque of the slope, the control unit 120 may control the braking control device 100 to generate a braking torque that is substantially the same as the driving torque of the engine 11. Additionally, if the driving torque of the engine 11 is less than the minimum braking torque of the slope, the braking control device 100 may be controlled to generate a braking torque that is substantially equal to the minimum braking torque of the slope.

Figure 5 shows changes in driving torque and braking torque of a vehicle according to one embodiment.

5, the braking torque generated by the braking control device 100 while the vehicle 1 is running is explained.

When the vehicle 1 is located on a slope, as shown in (a) of FIG. 5, at time T0, the engine control module 12 can identify the driver's intention to accelerate through the accelerator pedal 11a, and FIG. 5 As shown in (b), the engine 11 can be controlled to generate driving torque corresponding to the displacement of the accelerator pedal 11a. Additionally, the engine control module 12 may transmit information about the displacement of the accelerator pedal 11a and information about the driving torque of the engine 11 to the braking control device 100 through a communication network.

As shown in (c) of FIG. 5, the braking control device 100 can detect the spin of the wheel 2 at time T1. For example, the braking control device 100 may detect the spin of the wheel 2 based on the difference between the rotational speed of the driving wheel and the rotational speed of the driven wheel.

When the spin of the wheel 2 is detected, the BTCS function of the braking control device 100 is activated, as shown in (d) of FIG. 5.

Due to activation of the BTCS function, the braking control device 100 can supply hydraulic pressure for braking to the wheel cylinder, as shown in (e) of FIG. 5. At this time, the braking control device 100 may generate braking torque that is substantially equal to the driving torque of the engine 11 and is no greater than the driving torque of the engine 11.

As shown in (c) of FIG. 5, the spin of the wheel 2 can be reduced due to activation of the BTCS function.

Thereafter, as shown in (a) of FIG. 5, at time T2, the engine control module 12 can identify the intention to decelerate through the accelerator pedal 11a, and accelerate as shown in (b) of FIG. 5. The engine 11 may be controlled to generate reduced driving torque in response to the displacement of the pedal 11a. Additionally, the engine control module 12 may transmit information about the displacement of the accelerator pedal 11a and information about the reduced driving torque of the engine 11 to the braking control device 100 through a communication network.

The braking control device 100 may reduce braking torque in response to the reduced driving torque of the engine 11.

The braking control device 100 may compare the reduced braking torque and the minimum braking torque. The minimum braking torque represents the minimum braking torque that does not roll back on the slope where the vehicle 1 is located, and can be calculated using [Equation 1] and [Equation 2] described above.

When the reduced braking torque reaches the minimum braking torque, the braking control device 100 may generate a braking torque that is substantially equal to the minimum braking torque and is no less than the minimum braking torque. In other words, if the driving torque of the engine 11 is less than the minimum braking torque, the braking control device 100 may generate a braking torque that is substantially equal to the minimum braking torque and is not less than the minimum braking torque.

Thereby, when the driver takes his or her foot off the accelerator pedal 11a on a slope, the vehicle 1 can be prevented from rolling back.

Figure 6 shows the operation of a braking control device according to one embodiment.

6, the operation 1000 of the braking control device 100 is described.

The braking control device 100 identifies whether the slope of the road is greater than or equal to the reference slope (1010).

The controller 120 may determine the degree of slope of the road based on the output of the motion sensor 190 and compare the degree of slope of the road with the reference degree of slope.

If the slope of the road is greater than or equal to the standard slope (Yes in 1010), the braking control device 100 identifies whether the vehicle speed is less than the standard vehicle speed (1020).

The control unit 120 can determine the vehicle speed based on the output of the wheel speed sensor 180 and compare the vehicle speed with the reference vehicle speed.

If the vehicle speed is less than the reference vehicle speed (Yes in 1020), the braking control device 100 identifies whether the accelerator pedal displacement is greater than the reference displacement (1030).

The control unit 120 may determine the accelerator pedal displacement based on communication data received from the engine control module 12 and compare the accelerator pedal displacement with the reference displacement.

If the accelerator pedal displacement is greater than the reference displacement (Yes in 1030), the braking control device 100 identifies whether the spin of the wheel 2 is less than the reference spin (1040).

The control unit 120 may determine the spin of the wheel 2 based on the output of the wheel speed sensor 180 and compare the spin of the wheel 2 with the reference spin.

The slope of the road is not more than the standard slope (No in 1010), or the vehicle speed is not less than the standard vehicle speed (No in 1020), or the accelerator pedal displacement is not more than the standard displacement (No in 1030), or the wheel (No in 1030) If the spin in 2) is not less than the reference spin (No in 1040), the braking control device 100 outputs braking torque according to BTCS control (1045).

The control unit 120 may calculate the target braking torque based on the spin of the wheel 2, and may control the driving motor 150 and/or the valve block 170 to generate the calculated target braking torque.

If the spin of the wheel 2 is less than the reference spin (Yes in 1040), the braking control device 100 identifies whether the target braking torque is less than the driving torque of the engine 11 (1050).

The control unit 120 may calculate a target braking torque based on the spin of the wheel 2 and determine the driving torque based on communication data received from the engine control module 12. The control unit 120 may compare the target braking torque with the driving torque.

If the target braking torque is not less than the driving torque of the engine 11 (No in 1050), the braking control device 100 outputs a braking torque that is substantially equal to the driving torque and is no greater than the driving torque (1055).

The control unit 120 may change the target braking torque to a value that is substantially equal to the driving torque and is not greater than the driving torque. Additionally, the control unit 120 may control the driving motor 150 and/or the valve block 170 to generate a changed target braking torque.

If the target braking torque is less than the driving torque of the engine 11 (Yes at 1050), the braking control device 100 identifies whether the target braking torque is greater than or equal to the minimum braking torque (1060).

The control unit 120 may calculate the minimum braking torque using [Equation 1] and [Equation 2] based on the output of the motion sensor 190 and compare the target braking torque with the minimum braking torque.

If the target braking torque is not greater than or equal to the minimum braking torque (No in 1060), the braking control device 100 outputs a braking torque that is substantially equal to the minimum braking torque and is no less than the minimum braking torque (1065).

The control unit 120 may change the target braking torque to a value that is substantially equal to the minimum braking torque and is not smaller than the minimum braking torque. Additionally, the control unit 120 may control the driving motor 150 and/or the valve block 170 to generate a changed target braking torque.

If the target braking torque is greater than or equal to the minimum braking torque (Yes in 1060), the braking control device 100 outputs the current target braking torque (1070).

The controller 120 may control the driving motor 150 and/or the valve block 170 to generate the current target braking torque.

As described above, while the vehicle 1 is traveling at a low speed on a slope, the braking control device 100 may output a braking torque that is smaller than the driving torque of the engine 11 and greater than the minimum braking torque on the slope. Thereby, rollback of the vehicle 1 is prevented.

Meanwhile, the disclosed embodiments may be implemented in the form of a recording medium that stores instructions executable by a computer. Instructions may be stored in the form of program code, and when executed by a processor, may create program modules to perform operations of the disclosed embodiments. The recording medium may be implemented as a computer-readable recording medium.

As described above, the disclosed embodiments have been described with reference to the attached drawings. A person skilled in the art to which the present invention pertains will understand that the present invention can be practiced in forms different from the disclosed embodiments without changing the technical idea or essential features of the present invention. The disclosed embodiments are illustrative and should not be construed as limiting.

1: Vehicle 2: Wheel
10: drive system 10a: accelerator pedal
11: Engine 12: Engine control module
21: Transmission 40: Braking system
41: Braking device 42: Brake caliper
43: brake disc 44a, 44b: wheel cylinder
100: braking control device 101: brake pedal
103: reservoir 104: master cylinder
110: Hydraulic circuit 111: Main flow path 3
112: Auxiliary flow path 113a, 113b: Inlet valve
114a, 114b: outlet valve 117: hydraulic control unit
118: cut valve 120: control unit
121: Processor 122: Memory
123: can transceiver 130: brake pedal sensor
140: pressure sensor 150: driving motor
160: piston pump 161: cylinder
162: piston 170: valve block
180: wheel speed sensor 190: motion sensor

Claims (17)

In the braking control device installed on a vehicle including wheels,
a braking unit that applies braking torque to the wheel; and
It includes a control unit electrically connected to the braking unit,
The control unit,
Controlling the brake unit to apply braking torque to the wheel based on the position of the brake pedal,
Controlling the braking unit to generate a braking torque that is smaller than the driving torque of the vehicle's engine and greater than the minimum braking torque of the incline while the vehicle is traveling on an incline,
The control unit,
If the slope of the ramp is greater than or equal to the reference slope, the speed of the vehicle is less than the reference speed, the displacement of the accelerator pedal of the vehicle is greater than or equal to the reference displacement, and the spin of the wheel is less than the reference value, then the driving torque is less than the minimum braking force. Controlling the braking unit to generate a braking torque greater than the torque,
Determine a target braking torque based on the spin of the wheel,
A braking control device that controls the braking unit to generate braking torque equal to the driving torque when the target braking torque is greater than or equal to the driving torque. The method of claim 1, wherein the control unit,
A braking control device that identifies the minimum braking torque based on driving resistance due to the degree of inclination of the slope. delete delete The method of claim 1, wherein the control unit,
Determine a target braking torque based on the spin of the wheel,
A braking control device that controls the brake unit to generate a braking torque equal to the minimum braking torque when the target braking torque is less than the minimum braking torque. The method of claim 1, wherein the control unit,
Determine a target braking torque based on the spin of the wheel,
If the target braking torque is less than the driving torque and more than the minimum braking torque, a braking control device for controlling the brake unit to generate the determined target braking torque. The method of claim 1, wherein the control unit,
A braking control device that controls the brake unit to generate braking torque equal to the driving torque when the driving torque is greater than or equal to the minimum braking torque. The method of claim 1, wherein the control unit,
A braking control device that controls the brake unit to generate a braking torque equal to the minimum braking torque when the driving torque is less than the minimum braking torque. In the control method of a braking device installed in a vehicle including a wheel and a wheel cylinder corresponding to the wheel,
apply braking torque to the wheel based on the position of the vehicle's brake pedal;
While the vehicle is traveling on an incline, generate a braking torque that is smaller than the driving torque of the vehicle's engine and greater than the minimum braking torque on the incline,
Generating a braking torque that is less than the driving torque of the vehicle's engine and greater than the minimum braking torque of the slope,
If the slope of the ramp is greater than or equal to the reference slope, the speed of the vehicle is less than the reference speed, the displacement of the accelerator pedal of the vehicle is greater than or equal to the reference displacement, and the spin of the wheel is less than the reference value, then the driving torque is less than the minimum braking force. Including generating a braking torque greater than the torque,
determine a target braking torque based on the spin of the wheel;
If the target braking torque is greater than or equal to the driving torque, generating a braking torque equal to the driving torque. The method of claim 9, wherein the minimum braking torque is,
A control method of a braking device based on driving resistance depending on the degree of inclination of the ramp. delete delete 10. The method of claim 9, wherein generating a braking torque that is less than a driving torque of the engine of the vehicle and greater than a minimum braking torque of the slope comprises:
determine a target braking torque based on the spin of the wheel;
If the target braking torque is less than the minimum braking torque, generating a braking torque equal to the minimum braking torque. 10. The method of claim 9, wherein generating a braking torque that is less than a driving torque of the engine of the vehicle and greater than a minimum braking torque of the slope comprises:
determine a target braking torque based on the spin of the wheel;
If the target braking torque is less than the driving torque and more than the minimum braking torque, generating the determined target braking torque. 10. The method of claim 9, wherein generating a braking torque that is less than a driving torque of the engine of the vehicle and greater than a minimum braking torque of the slope comprises:
If the driving torque is greater than or equal to the minimum braking torque, generating a braking torque equal to the driving torque. 10. The method of claim 9, wherein generating a braking torque that is less than a driving torque of the engine of the vehicle and greater than a minimum braking torque of the slope comprises:
If the driving torque is less than the minimum braking torque, generating a braking torque equal to the minimum braking torque. In the braking control device installed in a vehicle including a wheel and a wheel cylinder corresponding to the wheel,
a piston pump that supplies hydraulic pressure to the wheel cylinder to apply braking torque to the wheel;
a drive motor that drives the piston pump;
a flow path extending from the piston pump to the wheel cylinder;
At least one valve opening the flow path; and
A control unit electrically connected to the drive motor and the at least one valve,
The control unit,
While the vehicle is traveling on a slope, if the driving torque of the engine of the vehicle is greater than the minimum braking torque of the slope, controlling at least one of the driving motor and the at least one valve to generate a braking torque equal to the driving torque,
A braking control device that controls at least one of the drive motor and the at least one valve to generate braking torque equal to the minimum braking torque when the driving torque is less than the minimum braking torque while the vehicle is traveling on an incline.

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