Steering decision device and procedure for vehicles, and steering decision system with the same

Abstract

Steering decision device of a vehicle, which device includes: a mode selection unit (310) configured to receive overlay requests from two or more steering-related control systems, and configured to determine an active state, an inactive state, or a ready state of each of the two or more steering-related control systems that sent the overlay requests, according to the type or priority of the system that sent the overlay request; a ProMode superimposed current calculation unit configured to calculate a final superimposed current value according to the superimposed requirement of the steering-related control system, which is determined by the mode selection unit (310) to be in the active state; and an output unit (350) for the final superposition current, which is configured to output the calculated final superposition current value to an electric power steering device.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention

[0001] The present invention relates to a decision method and a decision device of an electric power steering device of a vehicle, and more particularly relates to a steering decision method and a steering decision device for controlling an electric power steering device when override requests are received from a plurality of steering-related control systems in the vehicle, according to the priority of the steering-related control system that sent the corresponding override request. 2. Description of the state of the art

[0002] An electric power steering apparatus of the vehicle is configured to include: a torque sensor for detecting the torsion of a steering shaft connected to a steering wheel, an electric motor for rotating / moving a steering output shaft or a rack carrier by cooperating with the steering output shaft or the rack carrier, and a steering ECU for controlling the rotation of the electric motor according to a steering torque value measured by the torque sensor.

[0003] Basically, such an electric power steering device generates a steering assist current in proportion to a steering torque according to the driver's operation of a steering wheel and rotates the electric motor. That is, the electric power steering device performs a basic operation to assist the driver's steering effort.

[0004] However, with the recent development of a driving assistance system (DAS) and a demand for autonomous driving, autonomous steering control or active steering control has been developed to automatically operate the electric power steering system regardless of the driver's intention, in addition to a function of merely assisting the driver's steering effort.

[0005] According to autonomous steering control or active steering control, there are various steering-related control systems that affect the vehicle's electric power steering system.

[0006] An example of the vehicle's steering-related control system is a lane keeping support system (LKAS), which detects a driving lane and then steers the vehicle to travel in a specific lane, and steers the vehicle to maintain the lane by operating a steering system regardless of the driver's operation when there is a danger of lane departure.

[0007] In addition, in recent years, in accordance with demands for autonomous driving or the like, a traffic congestion assistance (TJA) system has been developed that performs control of following a leading vehicle in the low-speed driving environment such as a busy area or a congested area in the city center, and the TJA detects the leading vehicle in the congested area and automatically controls a steering system, an engine, and the braking system of a vehicle to thereby follow the leading vehicle.

[0008] Furthermore, a parking assistance system (PAS) detects a parking space to assist the vehicle in parking and automatically controls a steering system to move the vehicle into the parking space. In addition, other steering-related control systems, such as a vehicle stability management (VSM) system, may be provided, and new steering-related control systems not currently available may be added according to future technological developments.

[0009] However, since the steering-related control systems operate the electric power steering system depending on steering control values ​​that are calculated respectively, desired control cannot be performed in the case where two or more steering-related control systems simultaneously operate the electric power steering system.

[0010] In particular, there may be a system that is consistently more important for the safety of the vehicle among different steering-related control systems, and there may be a system that is only more important in a specific driving condition.

[0011] In such an environment where two or more steering-related control systems attempt to simultaneously control the electric power steering system, control of the same is required, but preparation for this has not yet been made.

[0012] From the document DE 10 2009 000 868 A1 closest to the application, a steering decision device is known which comprises a mode selection unit configured to receive overlay requests from two or more steering-related control systems and to determine an active state, an inactive state or a standby state of each of two or more steering-related control systems that have sent the overlay requests, according to the type or priority of the system that has sent the overlay request. SUMMARY OF THE INVENTION

[0013] One aspect of the present invention to solve such a problem is to provide an apparatus and a method for deciding the control operations of the steering-related control systems of an electric power steering apparatus in a vehicle including an electric power steering apparatus and two or more steering-related control systems for controlling the electric power steering apparatus.

[0014] Another aspect of the present invention is to provide an apparatus and method for deciding overlay requests received from two or more steering-related control systems, which are steering device operation commands or requests, in a vehicle having an electric power steering device and two or more steering-related control systems for controlling the electric power steering device.

[0015] Another aspect of the present invention is to provide an apparatus and method for selectively controlling operations of steering-related control systems according to the priority of the steering-related control system when receiving override requests from two or more steering-related control systems. These objects are achieved by a steering decision apparatus according to claim 1, a steering decision system according to claim 10, and a steering decision method according to claim 14.

[0016] According to the aforementioned aspects, an embodiment of the present invention provides a steering decision device of a vehicle, which device includes: a mode selection unit configured to receive overlay requests from two or more steering-related control systems, and configured to determine the active state, the inactive state, or the standby state of each of two or more steering-related control systems that sent the overlay requests, according to the type or priority of the system that sent the overlay request; a per-mode overlay current calculation unit configured to calculate a final overlay current value according to the overlay request of the steering-related control system determined by the mode selection unit to be in the active state;and a final superposition current output unit configured to output the calculated final superposition current value to an electric power steering device;

[0017] Another embodiment of the present invention provides a steering decision system of a vehicle, the system including: an electric power steering apparatus configured to include an electric power steering (EPS) control device, a first target current calculation unit, and an electric motor; two or more steering-related control systems configured to control the electric power steering apparatus;and a steering decision device configured to receive overlay requests from two or more steering-related control systems, configured to determine the active state, inactive state, or standby state of each of the two or more steering-related control systems that sent the overlay requests according to the type of priority of the system that sent the overlay request, and configured to calculate a final overlay current value according to the overlay request of the steering-related control system determined to be in the active state, and then transmit the same to a final target current calculation unit of the electric power steering device.;

[0018] Another embodiment of the present invention provides a steering decision method for a vehicle, including: an overlay receiving step of receiving overlay requests from two or more steering-related control systems; a mode selecting step of determining the active state, inactive state, or standby state of each of two or more steering-related control systems that sent the overlay requests according to the type or priority of the system that sent the overlay request; a per-mode overlay current calculating step of calculating a final overlay current value according to the overlay request of the steering-related control system determined to be in the active state in the mode selecting step;and a final superposition current output step for outputting the calculated final superposition current value to an electric power steering device;

[0019] As described above, according to the present invention, it is possible to decide the control operations of two or more steering-related control systems for the electric power steering apparatus in the vehicle including the electric power steering apparatus and two or more steering-related control systems for controlling the electric power steering apparatus.

[0020] More specifically, when steering device operation commands or requests (overlay requests) are received from two or more steering-related control systems, the steering device operation commands are selectively transmitted to the steering device according to the priority of the steering-related control system, so that optimal steering control can be performed while maintaining the stability of the vehicle.

[0021] When override requests from two or more steering-related control systems are received by the steering-related control systems such as VSM, LKAS, TJA, or PAS that automatically control the electric power steering device regardless of the driver's steering effort, it is possible to set various steering-related controls so that they do not interfere with each other by selectively executing steering control commands according to the priority of VSM, LKAS, TJA, or PAS. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above and other objects and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings in which: Fig. 1 illustrates the internal configuration of a vehicle including an electric power steering apparatus and two or more steering-related control systems (VSM, LKAS, TJA, and PAS) to which the present invention can be applied; Fig. 2 is a block diagram showing an entire steering decision system according to the embodiment of the present invention; Fig. 3 is a view showing the internal configuration of a steering decision device according to the embodiment of the present invention; Fig. 4 illustrates an operation flow of a steering decision device according to the embodiment of the present invention; Fig. 5 illustrates a flowchart of a mode selection process in a steering decision method according to the embodiment of the present invention; and Fig. 6 is a view for explaining a function of a soft transition unit used in the embodiment of the present invention. DETAILED DESCRIPTION OF EMBODIMENTS

[0023] Hereinafter, some embodiments of the present invention will be described in detail with reference to the accompanying illustrative drawings. When designating elements of the drawings by reference numerals, the same elements are designated by the same reference numerals even though they are shown in different drawings. Furthermore, in the following description of the present invention, a detailed description of known functions and configurations contained herein will be omitted if they would impair the clarity of the subject matter of the present invention.

[0024] Additionally, terms such as first, second, A, B, (a), (b), or the like may be used herein when describing components of the present invention. Each of these terms is not used to define an essential feature, order, or sequence of a corresponding component, but is merely used to distinguish the corresponding component from other components. In the event that a particular structural element is described as being "connected," "coupled," or "in contact" with another structural element, this should be interpreted to mean that another structural element may be "connected," "coupled," or "in contact" with the structural elements, as well as that the particular structural element may be directly connected or in direct contact with another structural element.

[0025] Fig. 1 illustrates the internal configuration of a vehicle including an electric power steering apparatus and two or more steering-related control systems (VSM, LKAS, TJA, and PAS) to which the present invention can be applied.

[0026] As in Fig. 1, an electric power steering apparatus and steering-related control systems that send control commands or requests to the electric power steering apparatus to then control the electric power steering apparatus are provided within the vehicle to which the present invention can be applied.

[0027] In this specification, the term "steering-related control systems" is used as a concept that includes all control systems that send steering commands or steering requests to enable a specific steering force to be applied to the electric power steering device for attitude control of the vehicle.

[0028] The steering commands or steering requests may include an override torque request or an override angle request requesting the addition of an additional steering current required by the corresponding steering-related control system to the basic steering assist current of the electric power steering device.

[0029] That is, the steering commands or steering requests supplied to the electric power steering device by the corresponding steering-related control systems can be expressed in a unit of a desired torque value, steering current value, or rotation angle of the electric motor.

[0030] The steering-related control systems that may be employed in the present invention may include, but are not limited to, a vehicle stability management (VSM) system 110, a lane keeping assistance (LKA) system 120, a traffic jam assistance (TJA) system 130, and a parking assistance system (PAS) 140.

[0031] The Vehicle Stability Management (VSM) system 110 maintains the stability of the vehicle body by integrally controlling a suspension device, a braking device, an engine driving force, and a steering device when vehicle stability is not ensured. This may occur, for example, in a case where: the vehicle body is unstable during braking because the traveling road surface is slippery or because the friction coefficients of the road surface are different for the left and right wheels; or the vehicle body is unstable when cornering due to improper steering operation by the driver.

[0032] Hereinafter, in this description, the vehicle stability management system is abbreviated as VSM, and the VSM 110 may cooperate with various sensors such as a wheel sensor 114 of the vehicle or with a subsystem such as an electronic stability control (ESC) 112 to maintain the vehicle attitude.

[0033] The lane keeping support system (LKAS) 120 can detect the lane using a front camera 122 or the like, and can perform lane-keeping control, which performs lane-keeping control by operating the steering system regardless of the driver's operation when there is a danger of lane departure. Hereinafter, the lane keeping support system will be abbreviated as LKA in this specification.

[0034] The traffic congestion assistance (TJA) system 130 performs control of following a leading vehicle in a low-speed driving environment, such as a busy area or a congested area in a city center. It detects the leading vehicle in the congested area using the front camera 122 and automatically controls a steering system, an engine, and a braking system of the vehicle to thereby follow the leading vehicle. Hereinafter, the traffic congestion assistance system will be abbreviated as TJA.

[0035] The steering-related control systems such as LKA or TJA, which perform steering control in the driving course of the vehicle independent of the driver's steering intention, are collectively referred to as a driving steering system in this specification.

[0036] The driving guidance system is separated from the general vehicle stability management (VSM) system or the parking assistance system (PAS) and may further include a lane change assistance system (LCA), an adaptive cruise control system (ACC) or an intelligent cruise control system (SCC), as well as LKA and TJA.

[0037] The Lane Change Assistance (LCA) system operates the steering system through the driver's intention or automatic control to then assist the vehicle in the process of changing lanes or to change lanes automatically.

[0038] The adaptive cruise control system (ACC) or intelligent cruise control system (SCC) integrally controls a steering device, an engine drive mechanism, and a braking device of the vehicle to thereby follow a forward target such as a preceding vehicle or the lane while the vehicle is traveling.

[0039] Although only LKA and TJA are described below as an example of the driving guidance system, the same description can be applied to other systems such as LCA or ACC (SCC).

[0040] The parking assistance system (PAS) 140 automatically or semi-automatically assists the parking of the vehicle. It detects a parking space and obstacles using a camera 122 or an ultrasonic sensor 142, and then assists the vehicle in moving toward the parking space by actuating the electric power steering device. Hereinafter, the parking assistance system will be abbreviated as PAS in this description.

[0041] The steering-related control systems such as the VSM 110, the LKA 120, the TJA 130, or the PAS 140, when activated, calculate an override steering current required for operation in their mode and then transmit it to the electric power steering (EPS) device 160, and the electric power steering device adds the override steering current to the basic steering assist current to then determine the final target current and then actuate the motor.

[0042] In some cases, when two or more steering-related control systems of the VSM 110, the LKA 120, the TJA 130, and the PAS 140 are activated simultaneously, two or more superimposed steering currents are added to perform steering control. Accordingly, desired steering control cannot be performed.

[0043] For example, when the VSM is also activated due to the occurrence of slippage of the vehicle body in the running state in which the LKA is in operation, a superimposed steering current value A of the LKA and a superimposed steering current value B of the VSM are added to then perform control of the electric power steering device.

[0044] In this case, a steering current of magnitude A is required to maintain the lane (LKA). However, the LKA and VSM cannot operate sufficiently if the steering control is performed with a value of A+B.

[0045] In addition, the steering-related control systems may have a priority.

[0046] For example, the VSM may have a higher priority than the PAS because the VSM, which is related to controlling the vehicle body in a dangerous situation, is more important than the PAS, which is related to parking assistance in a low-speed situation.

[0047] In addition, the driving guidance system such as the LKA or the TJA can have a priority between the priorities of the VSM and the PAS.

[0048] Therefore, when overlay requests from two or more steering-related control systems having different priorities as described above are transmitted to the electric power steering apparatus, the present invention proposes a method of determining the active mode of the steering-related control system to be activated according to the type and state of the steering-related control system that sent the overlay request, and determining the final overlay steering current according to the determination.

[0049] Fig. Fig. 2 is a block diagram showing an entire steering decision system according to the embodiment of the present invention, and Fig. 3 is a detailed functional block diagram of a steering decision device according to the present invention.

[0050] As in Fig. 2, the entire steering decision system according to the embodiment of the present invention is configured to include: a steering decision device 300 according to the present invention, an electric power steering device 260, and LKA / TJA 220, PAS 230, and VSM 240 corresponding to two or more steering-related control systems.

[0051] That is, although the LKA / TJA 220 is used as an example of a driving steering system in the embodiment of Fig. 2, this is not limited to this.

[0052] The electric power steering device 260 may include an electric power steering (EPS) control device 262 that receives a steering torque value by a driver's steering force from the torque sensor or the like and then generates a steering assist current, a final target current calculation unit 264 that receives a final superimposed current value transmitted from the steering decision device according to the present invention and adds it to the steering assist current value calculated by the aforementioned EPS control device to then calculate a final target current value, and an electric motor 266 controlled by the final target current value.

[0053] The steering decision device 300 according to the present embodiment is a device that performs the following functions: receiving overlay requests from two or more steering-related control systems; determining the active state, inactive state, and standby state of each of the two or more steering-related control systems that sent the overlay requests according to the type or priority of the system that sent the overlay request; calculating the final overlay current value according to the overlay request of the steering-related control system determined to be in the active state; and transmitting it to the final target current calculation unit of the electric power steering device.

[0054] Such a steering decision device may be implemented by hardware and / or software, and may be included within the vehicle as a separate device or may be included as part of a typical vehicle control system.

[0055] In addition, the steering decision device 300 may be configured to include: a mode selection unit 310 for determining the state of the steering-related control system that sent the overlay request from the two or more steering-related control systems, a per-mode overlay current calculation unit, and a final overlay current output unit 350.

[0056] In the present specification, the "overlay request" refers to a request message sent from the steering-related control system such as VSM, LKA / TJA, or PAS to the steering decision device according to the present invention to perform the vehicle body target control, and may include an overlay torque value, an overlay steering angle value, overlay motor rotation angle information, or the like.

[0057] In addition, the “superimposed current (value)” is a motor current value created based on a superimposed torque value, a superimposed steering angle value, or superimposed motor rotation angle information included in the superimposed request sent from each steering-related control system to be sent to the steering device, and is a separate concept from the basic steering assist angle generated by the EPS control device 262 based on a driver's steering torque.

[0058] The "final superimposed current (value)" means a superimposed current value of an individual steering-related control system selected by the steering decision device according to the present invention, and the final superimposed current is added to the basic steering assist current of the electric power steering device to thereby determine the final target current for driving the electric motor.

[0059] The mode selection unit 310 included in the steering decision device 300 performs the following functions: receiving overlay requests from two or more steering-related control systems; and determining the active state, inactive state, or standby state of each of the two or more steering-related control systems that sent the overlay requests according to the type or priority of the system that sent the overlay request.

[0060] Specifically, in the case where there is an override request from the second steering-related control system while the first steering-related control system is activated, if the priority of the second steering-related control system is higher than the priority of the first steering-related control system, the mode selection unit 310 allows the second steering-related control system to be in the active state and allows the first steering-related control system to be in the inactive state. In addition, if the priority of the first steering-related control system is higher than the priority of the second steering-related control system, the mode selection unit 310 maintains the first steering-related control system in the active state and allows the second steering-related control system to be in the standby state.

[0061] In addition, when the overlay requests are input simultaneously or sequentially from two or more steering-related control systems, the mode selection unit 310 may allow the steering-related control system having a higher priority to be in the active state and may allow the steering-related control system having a lower priority to be in the standby state, of the corresponding steering-related control systems.

[0062] The operation of selecting the mode by the mode selection unit 310 will be described in detail below with reference to the Fig. 4 and Fig. 5 described.

[0063] Two or more steering-related control systems including the first and second steering-related control systems according to the present invention may include, but are not limited to, a vehicle stability management (VSM) system, a lane keeping assist (LKA) system, a traffic jam assist (TJA) system, and a parking assist system (PAS).

[0064] That is, the steering-related control systems may include other types of control systems for controlling the electric power steering device, such as VSM, LKA, TJA, and PAS, and the respective steering-related control systems are assigned priorities in consideration of an effect on the vehicle, the driving condition, or the like.

[0065] For example, among VSM, LKA, TJA, and PAS, the VSM may have the highest priority and the PAS may have the lowest priority, while the LKA and TJA have the same priority.

[0066] In addition, the priority of the steering-related control system may be constantly assigned or may vary with the driving condition.

[0067] For example, in the case where a slippery road condition is detected, the VSM may have the highest priority, and the LKA, TJA, and PAS may have the same lower priority. Additionally, in the case of a speed lower than a specific value, the TJA or PAS may have the highest priority, and the VSM and LKA may have lower priorities than these.

[0068] The priority of the steering-related control system may be given by the corresponding system considering the effect of the steering control on the vehicle stability or driving comfort, and another steering-related control system with a constant priority may be added to the VSM, the LKA, the TJA, and the PAS.

[0069] For convenience, the following description assumes that: the VSM has the first priority; the LKA and the TJA have the same second priority; and the PAS has the third priority.

[0070] The per-mode superposition current calculation unit included in the steering decision device 300 according to the present invention may perform a function of calculating a final superposition current value according to the superposition request of the steering-related control system determined by the mode selection unit to be in the active state, and more specifically, it may include a VSM functional unit 340 for calculating a VSM superposition current, an LKA / TJA functional unit 320 for calculating an LKA or TJA superposition current, and a PAS functional unit 330 for calculating a PAS superposition current.

[0071] The active state refers to the state in which the corresponding superposition current is reflected by the steering-related control system to the final target current value, and more simply, it refers to the state in which the corresponding steering-related control system operates.

[0072] In addition, the inactive state refers to the state in which the operation in the active state is stopped by the mode selecting unit, and is different from the standby state described later in that the stopped state is maintained until the overlay request is sent again to the steering decision device.

[0073] The standby state refers to the state in which the operation is halted until the operation of the currently activated steering-related control system is completed, and the standby mode is converted to the active mode after the overlay request of the activated steering-related control system is executed, which is different from the inactive mode in which the halted mode is maintained until the overlay request is sent to the steering decision device again.

[0074] The mode selection unit 310 may determine the state of each steering-related control system that sent the overlay request and may then create at least one flag (i.e., at least one of an active flag, an inactive flag, or a standby flag) to then transmit the same to the per-mode overlay current calculation unit.

[0075] In the present description, for convenience, the active character or state is expressed as "1", the inactive character or state is expressed as "0", the ready flag or state is expressed as "S", and the state in which the overlay request is received is expressed as "R".

[0076] At least one of the VSM functional unit 340, the LKA / TJA functional unit 320, and the PAS functional unit 330 constituting the ProMode superposition current calculation unit may include a soft transition unit that gradually changes the superposition current when its state is changed.

[0077] For example, in the case of a transition of the corresponding steering-related control system from the inactive state or the standby state to the active state, the soft transition unit performs a function of gradually increasing the corresponding superposition current from zero to a target value. In contrast, in the case of a transition of the corresponding steering-related control system from the active state to the inactive / standby state, the soft transition unit performs a function of gradually decreasing the corresponding superposition current from the current value to zero.

[0078] An example of a change in the superposition current through the soft transfer unit is described in detail below with reference to the Fig. 6 described.

[0079] According to the smooth transition unit, it is possible to ensure the safety of the vehicle body and enhance a driver's steering feeling by preventing an abrupt change in the superposition current when the activated steering-related control system is changed.

[0080] As described above, in the case of using the steering decision apparatus and the steering decision systems according to the embodiment of the present invention, safe steering control can be performed by selectively or sequentially controlling the operation depending on the priority or the like even when overlay requests are input from a plurality of steering-related control systems such as VSM, LKA, TJA or PAS.

[0081] Fig. 4 illustrates an operation procedure by the steering decision device according to the embodiment of the present invention.

[0082] The description of Fig. 4 is assumed that VSM, LKA, TJA and PAS are provided as an example for the steering-related control systems and the VSM has the first priority, the LKA and the TJA have the same second priority and the PAS has the third priority.

[0083] The left table shows the state (before) at the time the steering decision device of the present invention receives the overlay requests, and the right table shows the state (after) after the mode selection by the steering decision device of the present invention is completed.

[0084] In addition, as described above, the active state is expressed as "1", the inactive state is expressed as "0", the standby state is expressed as "S", and the state in which the overlay request is received is expressed as "R".

[0085] Points 1 to 3 in Fig. 4 show the case where the overlay request is received from a single steering-related control system, respectively. In this case, the steering-related control system that sent the overlay request is activated to operate according to a typical method instead of using the steering decision device according to the present invention. That is, a overlay current of the activated steering-related control system is generated and sent to the electric power steering device to then actuate the electric steering motor.

[0086] Points 4 to 7 in Fig. 4 correspond to the case where overlay requests from two or more steering-related control systems are received simultaneously or successively at a short interval in a state where there is no steering-related control system enabled for operation.

[0087] In this case, the mode selection unit 310 of the steering decision device determines the steering-related control system having a higher priority as being in the active state (1) and determines the steering-related control system having a lower priority as being in the standby state (S) from the two or more steering-related control systems that have sent the overlay requests.

[0088] For example, when the overlay requests are received simultaneously from the VSM and the PAS, as shown in item 5, the VSM with a higher priority is selected to be in the active state (1), and the PAS with a lower priority is determined to be in the standby state (S).

[0089] When the overlay requests are received simultaneously from all three steering-related control systems, the VSM, the LKA / TJA and the PAS, as shown in item 7, only the VSM with the highest priority is selected to be in the active state (1), and the LKA / TJA and the PAS with lower priorities than this are determined to be in the standby state (S).

[0090] The overlay requests of the steering-related control systems determined to be in the standby state (S) can be performed only if there is no other overlay request after the operation of the currently activated steering-related control system is completed.

[0091] The standby state (S) may be maintained for a constant period of time, and may be converted to the inactive state (0) after a predetermined time has elapsed by using a timer function.

[0092] In addition, after the operation of the steering-related control system in the active state, it can be determined whether the standby state (S) is released or not and whether re-execution is to be performed or not by detecting the surrounding situation using a separate sensor.

[0093] For example, if the PAS is in the standby state while the VSM is in the active state (point 5 of Fig. 4) It can be determined whether a PAS button continues to be pressed or whether an image of the parking space is captured by a camera after the termination of the VSM control, and then the operation of the PAS can be performed in the standby state.

[0094] Points 8 to 13 of Fig. 4 correspond to the case in which overlay requests are received from one or more of the second other steering-related control systems while the first steering-related control system is in the active state.

[0095] In this case, when the priority of the second steering-related control system is higher than the priority of the first steering-related control system, the mode selection unit 310 of the steering decision device 300 configures the second steering-related control system to be in the active state (1) and converts the first steering-related control system to the inactive state (0).

[0096] On the other hand, when the priority of the first steering-related control system is higher than the priority of the second steering-related control system, the mode selection unit 310 maintains the active state (1) of the first steering-related control system, and configures the second steering-related control system to be in the standby state (S).

[0097] For example, as stated in point 10 of Fig. 4, in the state in which the LKA / TJA is activated, when an overlay request is received from the VSM having a higher priority than the same, the VSM is configured to be in the active state, and the LKA / TJA is stopped in operation to then be converted to the inactive state.

[0098] In contrast, as stated in point 11 of Fig. 4, in the state in which the LKA / TJA is activated, when an overlay request is received from the PAS having a lower priority than the same, the LKA / TJA is maintained in the active state (1), and the PAS is configured to be in the standby state (S).

[0099] That is, when the override request is received from the steering-related control system having a higher priority than that of the steering-related control system currently in operation, the previous control of the operation is immediately stopped so that the control corresponding to the higher priority having a greater effect on the vehicle can be operated without error.

[0100] When the override request is received from the steering-related control system that has a lower priority than the steering-related control system currently in operation, the previous control of the operation is continued, and the later received override request waits for a while to be executed after the previous control is completed. Therefore, two or more controls can be executed consecutively to thereby improve the efficiency.

[0101] Fig. 5 illustrates a flowchart of a mode selection process in a steering decision method according to the embodiment of the present invention.

[0102] The steering decision method according to the present invention can be implemented by the steering decision device as shown in Fig. 3 shown, which is implemented inside the vehicle.

[0103] The entire steering decision method according to the present invention may include: an overlay receiving step of receiving overlay requests from two or more steering-related control systems; a mode selecting step of determining the active state, inactive state, or standby state of each of the two or more steering-related control systems that sent the overlay requests according to the type or priority of the system that sent the overlay request; a per-mode overlay current calculating step of calculating a final overlay current value according to the overlay request of the steering-related control system determined to be in the active state in the mode selecting step; and a final overlay current outputting step of outputting the calculated final overlay current value to an electric power steering device.

[0104] Of the above operations, the mode selection step will be explained in detail with reference to Fig. 5 described.

[0105] In the mode selection step of the steering determination method according to the present invention, first, the steering decision device receives overlay requests from the steering-related control systems such as VSM, LKA, TJA, or PAS provided in the vehicle (S510).

[0106] Next, it is determined whether or not one of the steering-related control systems is operating (S520), and if no steering-related control system is operating, it is determined whether or not two or more overlay requests have been received (S530).

[0107] If there is a steering-related control system that is operating in step S520, it is determined whether or not the priority of the steering-related control system that sent the overlay request is higher than the priority of the steering-related control system that is currently operating (S540).

[0108] If the priority of the steering-related control system that sent the overlay request is higher than the priority of the steering-related control system that is currently operating, the state of the steering-related control system in operation is converted to the inactive state (0), and the steering-related control system that sent the overlay request is configured to be in the active state (1) (S542).

[0109] If the priority of the steering-related control system that sent the overlay request is lower than the priority of the steering-related control system that is currently operating, the state of the steering-related control system that is currently operating is maintained in the active state (1), and the steering-related control system that sent the overlay request is configured to be in the standby state (S) (S544).

[0110] If no steering-related control system is in operation and there are two or more overlay requests in step S530, the steering-related control system having a higher priority is configured to be in the active state (1), and the one or more remaining steering-related control systems of the two or more steering-related control systems that sent the overlay requests having the lower priorities are configured to be in the standby state (S) (S532).

[0111] Of course, if no steering-related control system is in operation and there is an overlay request in step S530, the operation of the corresponding steering-related control system may be performed (S534).

[0112] Fig. 6 is a view for explaining a function of the soft transition unit used in the embodiment of the present invention.

[0113] As described above, according to the present invention, at least one of the VSM functional unit 340, the LKA / TJA functional unit 320, or the PAS functional unit 330 included in the ProMode superimposed current calculation unit of the steering decision device 300 may include a soft transition unit that gradually changes the superimposed current when its state is changed.

[0114] Fig. 6 explains the effect of the soft transition unit and illustrates, for example, how in point 10 of Fig. 4, the case where the overlay request is received from the VSM having a higher priority than the LKA / TJA while the LKA / TJA is in operation.

[0115] In this case, the LKA / TJA is changed from the active state to the inactive state, and the VSM is configured to be in the active state.

[0116] Therefore, as in Fig. 6, the LKA / TJA superimposed current is supplied to the electric power steering apparatus at the time before the mode change, and it is required that the VSM superimposed current be added to the target steering current after the mode change.

[0117] At this time, in order to prevent an abrupt change in the current between two superposition currents (between the LKA / TJA superposition current and the VSM superposition current), the soft transition unit 342 included in the VSM functional unit 340 performs control such that the current between two superposition currents is gradually changed (dashed line) during the mode change period (Δt).

[0118] For this purpose, the superposition current calculation unit (the VSM functional unit) activated when the mode is changed may receive the final superposition current value (the LKA / TJA current) at the time immediately before the mode change from the superposition current calculation unit (the LKA / TJA functional unit) previously operated, and may perform a gradual increase or decrease of the superposition current by using the soft transition unit 342.

[0119] Even if the steering-related control system activated by the steering decision device is changed according to the present embodiment, since an abrupt change in the control current supplied to the electric steering motor can be prevented by the smooth transition unit, it is possible to provide stable steering control and steering feel.

[0120] As described above, according to the steering decision device and the related method in the embodiment of the present invention, when superimposing requests from two or more steering-related control systems are received by the steering-related control systems (such as VSM, LKA, TJA, or PAS) for automatically controlling the electric power steering apparatus regardless of a driver's steering force, steering control commands can be selectively executed according to the priority of the VSM, LKA, TJA, or PAS, thereby setting various steering-related controls so as not to interfere with each other.

Claims

[1] Steering decision device of a vehicle, which device comprises: a mode selection unit (310) configured to receive overlay requests from two or more steering-related control systems, and configured to determine an active state, an inactive state, or a standby state of each of two or more steering-related control systems that sent the overlay requests, according to the type or priority of the system that sent the overlay request; a per-mode overlay current calculation unit configured to calculate a final overlay current value according to the overlay request of the steering-related control system determined by the mode selection unit (310) to be in the active state; and a final superimposed current output unit (350) configured to output the calculated final superimposed current value to an electric power steering device. [2] A steering decision device of a vehicle according to claim 1, wherein the steering-related control systems are at least one of a vehicle stability management (VSM) system (110), a driving steering system, or a parking assist system (PAS) (140). [3] A steering decision device of a vehicle according to claim 1 or 2, wherein the driving steering system includes at least one of a lane keeping assistance (LKA) system (120), a traffic congestion assistance (TJA) system (130), a lane change assistance (LCA) system, or an adaptive cruise control (ACC) system. [4] A vehicle steering decision device according to claim 2 or 3 as dependent on claim 2, wherein the VSM (110) has the highest priority and the PAS (140) has the lowest priority. [5] A steering decision device of a vehicle according to any one of claims 1 to 4, wherein the pro-mode superimposed current calculation unit includes: a VSM functional unit (340) for calculating a VSM superimposed current; an LKA / TJA functional unit (320) for calculating an LKA or TJA superimposed current; and a PAS functional unit (330) for calculating a PAS superimposed current. [6] A steering decision device of a vehicle according to claim 5, wherein at least one of the VSM functional unit (340), the LKA / TJA functional unit (320) or the PAS functional unit (330) includes a soft transition unit (322, 332, 342) which gradually changes the corresponding superimposed current in the event of its transition from the inactive state or the standby state to the active state. [7] A steering decision device of a vehicle according to any one of claims 1 to 6, wherein, in the case where there is an override request of the second steering-related control system while the first steering-related control system is activated, when the priority of the second steering-related control system is higher than the priority of the first steering-related control system, the mode selection unit (310) allows the second steering-related control system to be in the active state and allows the first steering-related control system to be in the inactive state, and when the priority of the first steering-related control system is higher than the priority of the second steering-related control system, the mode selection unit (310) maintains the first steering-related control system in the active state and allows the second steering-related control system to be in the standby state. [8] A steering decision device of a vehicle according to any one of claims 1 to 7, wherein, when overlay requests are input from the first and second steering-related control systems, the mode selection unit (310) of the first and second steering-related control systems allows the steering-related control system having a higher priority to be in the active state and allows the steering-related control system having a lower priority to be in the standby state. [9] A steering decision device of a vehicle according to any one of claims 5 to 8, insofar as this claim is dependent on claim 5, wherein at least one of the VSM functional unit (340), the LKA / TJA functional unit (320) or the PAS functional unit (330) includes a soft transition unit which gradually changes the corresponding superimposed current in the event of its transition from the inactive state or the standby state to the active state. [10] Steering decision system of a vehicle, which system comprises: an electric power steering apparatus (260) configured to include an electric power steering (EPS) controller (262), a final target current calculation unit (264), and an electric motor (266); two or more steering-related control systems configured to control the electric power steering device (260); and a steering decision device configured to receive overlay requests from two or more steering-related control systems to determine an active state, an inactive state or a standby state of each of two or more steering-related control systems that have sent the overlay requests, according to the type of the system that sent the overlay request or the priority thereof, and calculating a final overlay current value according to the overlay request of the steering-related control system determined to be in the active state, and then sending the same to a final target current calculation unit (264) to the electric power steering apparatus (260). [11] A steering decision system of a vehicle according to claim 10, wherein in the case where an override request of the second steering-related control system is present while the first steering-related control system is activated, when the priority of the second steering-related control system is higher than the priority of the first steering-related control system, the steering decision device allows the second steering-related control system to be in the active state and allows the first steering-related control system to be in the inactive state, and when the priority of the first steering-related control system is higher than the priority of the second steering-related control system, the steering decision device keeps the first steering-related control system in the active state and allows the second steering-related control system to be in the standby state. [12] A steering decision system of a vehicle according to claim 10 or 11, wherein the first and second steering-related control systems are at least one of a vehicle stability management (VSM) system (240), a cruise control system including at least one of a lane keeping assist (LKA) system (220) or a traffic congestion assist (TJA) system (220), or a parking assist system (PAS) (230), and the VSM (240) has the highest priority and the PAS (230) has the lowest priority. [13] A steering decision system of a vehicle according to any one of claims 10 to 12, wherein the steering decision device includes: a VSM functional unit (340) for calculating a VSM superimposed current; an LKA / TJA functional unit (320) for calculating an LKA or TJA superimposed current; and a PAS functional unit (330) for calculating a PAS superimposed current, and wherein at least one of the VSM functional unit (340), the LKA / TJA functional unit (320), or the PAS functional unit (330) includes a soft transfer unit (322, 332, 342) which gradually changes the corresponding superimposed current in the event of its transition from the inactive state or standby state to the active state. [14] Steering decision method of a vehicle, which method comprises: Receiving overlay requests from two or more steering-related control systems; determining an active state, an inactive state, or a ready state of each of two or more steering-related control systems that sent the overlay requests, according to the type or priority of the system that sent the overlay request; Calculating a final overlay current value according to the overlay requirement of the steering-related control system, which was determined to be in the active state when determining the state; and Outputting the calculated final superposition current value to an electric power steering device (260). [15] The method of claim 14, wherein in determining the state in the case where an overlay request of the second steering-related control system is present while the first steering-related control system is activated, if the priority of the second steering-related control system is higher than the priority of the first steering-related control system, the second steering-related control system is configured to be in the active state and the first steering-related control system is configured to be in the inactive state, and when the priority of the first steering-related control system is higher than the priority of the second steering-related control system, the first steering-related control system is maintained in the active state and the second steering-related control system is configured to be in the standby state.

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