Patent Description:
The present invention relates to an apparatus, a method and a computer readable storage medium for calculating torque of an electric vehicle for exiting drift driving.

Drift driving is a driving method in which a driver intentionally slides a rear wheel while maintaining control of a vehicle in order to maintain a high exit speed in a corner, thereby causing oversteering and passing the corner. In an electric vehicle, the above-described drift driving may be implemented by distributing torque to only a rear wheel motor. From <CIT> an apparatus for calculating torque of a vehicle for exiting drift driving, the apparatus comprising: a processor; and a non-transitory computer-readable storage medium storing a program which, when executed by the processor, causes the processor to perform: determining a driver's intention to exit drift driving based on an opening degree of an accelerator pedal and a steering angle, and calculating target torque of a front wheel motor based on the opening degree of the accelerator pedal when the intention to exit drift driving is determined, wherein the determining a driver's intention comprises: determining that there is an intention to exit drift driving when the steering angle is less than a first reference steering angle and the opening degree of the accelerator pedal is greater than a first reference opening degree.

An aspect of the present invention is to provide an apparatus, a method, and a computer-readable storage medium for calculating torque of a vehicle for exiting drift driving.

In addition, an aspect of the present invention is to provide an apparatus, a method, and a computer-readable storage medium for accurately setting target torque of a front wheel motor required for exiting drift driving, and preventing non-linear behavior of the vehicle due to abrupt torque application.

According to an aspect of the present invention, an apparatus for calculating torque of a vehicle for exiting drift driving according to claim <NUM> is provided. The apparatus includes a processor and a non-transitory computer-readable storage medium storing a program which, when executed by the processor, causes the processor to perform: determining a driver's intention to exit drift driving based on an opening degree of an accelerator pedal and a steering angle; and calculating target torque of a front wheel motor based on the opening degree of the accelerator pedal when the driver's intention to exit drift driving is determined.

According to an aspect of the present invention, a method for calculating torque of a vehicle for exiting drift driving according to claim <NUM> is provided. The method includes a first operation of determining a driver's intention to exit drift driving based on an opening degree of an accelerator pedal and a steering angle; and a second operation of calculating target torque of a front wheel motor based on the opening degree of the accelerator pedal, when the driver's intention to exit drift driving is determined.

According to an aspect of the present invention, a non-transitory computer-readable storage medium may store a program which, when executed by a processor, causes the processor to perform the method.

The above and other aspects, features, and advantages of the present invention will be more clearly understood from the following detailed description, taken in conjunction with the accompanying lead-outs, in which:.

Hereinafter, embodiments in the present invention will be described hereinafter with reference to the accompanying drawings. The invention may, however, be exemplified in many different forms and should not be construed as being limited to the specific embodiments set forth herein. Rather, these embodiments are provided so that this invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, the same reference numerals will be used throughout to designate the same or like elements, and the shapes and dimensions of elements may be exaggerated for clarity.

<FIG> is a block diagram of an overall system <NUM> including an apparatus <NUM> for calculating torque of a vehicle according to an embodiment of the present invention.

In illustrating the present invention, a vehicle V illustrated in <FIG> may be an All-Wheel Drive (AWD) electric vehicle having a front wheel motor <NUM> for driving a front wheel <NUM> and a rear wheel motor <NUM> for driving a rear wheel <NUM>, respectively. Also, in illustrating the present invention, the vehicle V is illustrated on a premise that it is an electric vehicle, but the vehicle V may also be an internal combustion engine vehicle in which the front wheel <NUM> and the rear wheel <NUM> may be driven independently.

In addition, the present invention is based on the premise that the above-described vehicle V is in a drift driving state, and how the vehicle exits the drift driving state, that is, the purpose of the present invention is that how to determine a driver's intention to exit drift driving, and how to obtain the target torque of the front wheel motor <NUM> when the driver's intention to exit drift driving is determined.

First, a driving information detector <NUM> may detect a state of the vehicle V and transmit the same to the apparatus <NUM> for calculating torque.

To this end, the driving information detector <NUM> may include a sensor for detecting an opening degree of an accelerator pedal, a sensor for detecting a steering angle, a sensor for measuring acceleration in a longitudinal or a lateral direction, and the like.

Meanwhile, the motor controller <NUM> may control driving and torque of motors <NUM> and <NUM> according to the torque transmitted from the apparatus <NUM> for calculating torque, and store electricity generated from the motors <NUM> and <NUM> during regenerative braking to a battery <NUM>. To this end, one or a plurality of microprocessors may be provided in the motor controller <NUM>, and the one or a plurality of microprocessors may be operated by a program set to execute a method for driving the motors <NUM> and <NUM> and controlling the torque.

The battery <NUM> may be comprised of a plurality of unit cells, and supply a driving voltage to the motors <NUM> and <NUM>, and may be charged with a voltage generated by the motors <NUM> and <NUM> during regenerative braking.

Meanwhile, the brake controller <NUM> may control a brake by controlling hydraulic pressure supplied to brake cylinders of respective driving wheels <NUM> and <NUM>. For this purpose, one or a plurality of microprocessors may be provided in the brake controller <NUM>, and the one or the plurality of microprocessors may operate according to a program set for executing a method for controlling hydraulic pressure.

Meanwhile, the torque calculating apparatus <NUM> may include a determination unit <NUM> and torque calculating unit <NUM>.

The determination unit <NUM> of the apparatus for calculating torque <NUM> may determine a driver's intention to exit drift driving based on an opening degree of an accelerator pedal and a steering angle.

According to an embodiment of the present invention, the determination unit <NUM> may determine that there is a driver's intention to exit drift driving when the steering angle is less than a first reference steering angle and the opening degree of the accelerator pedal is greater than a first reference opening degree.

<FIG> is a view illustrating a process of obtaining a cumulative count value for determining a driver's intention to exit drift driving according to an embodiment of the present invention.

Specifically, as illustrated in <FIG>, the determination unit <NUM> may count a time at which the steering angle is less than a first reference steering angle and the opening degree of the accelerator pedal is greater than a reference opening degree and cumulate the same, and in this case, when a cumulative count value K is greater than or equal to a preset first cumulative count value K1, the determination unit <NUM> may determine that there is an intention to exit drift driving.

That is, as illustrated in <FIG>, a point in time T1 at which the cumulative count value K is a first cumulative count value K1 may be determined as a point in time at which there is an intention to exit drift driving.

Meanwhile, the determination unit <NUM> may count a time at which the steering angle is less than a first reference steering angle and an opening degree of an accelerator pedal is greater than a reference opening degree. When the steering angle is greater than a second reference steering angle, the second steering angle being greater than the first steering angle, the determination unit <NUM> may reset a cumulative count value K. This is because, in this case, it may be determined that the driver desires drift driving again.

Here, the second reference steering angle may be a value, greater than the first reference steering angle, which is to provide a dead time to prevent frequent reset. It should be noted that the second reference steering angle and the first steering angle as described above are not limited to specific values in the present invention, since the second reference steering angle and the first steering angle, described above are values that can be set according to needs of those skilled in the art.

Meanwhile, when the driver's intention to exit drift driving is determined, the torque calculating unit <NUM> of the torque calculating apparatus <NUM> may calculate a target torque of the front wheel motor <NUM> based on the opening degree of the accelerator pedal.

According to an embodiment of the present invention, the torque calculating unit <NUM> may calculate the target torque of the front wheel motor <NUM> by multiplying the required torque according to the opening degree of the accelerator pedal by a sensitivity factor SF according to the opening degree of the accelerator pedal and a weight factor WF according to the cumulative count value K. Hereinafter, a process of calculating the target torque of the front wheel motor will be described in detail with reference to <FIG>.

<FIG> is a view illustrating a process of calculating a target torque of a front wheel motor according to an embodiment of the present invention.

As illustrated in <FIG>, first, the torque calculating unit <NUM> may be configured to multiply required torque according to an opening degree of an accelerator pedal by a sensitivity factor SF according to an opening degree of an accelerator pedal using a multiplier 152c.

Here, the required torque according to the opening degree of the accelerator pedal is torque distributed to the front wheel motor <NUM> among the total required torque according to the opening degree of the accelerator pedal, and may have a preset value. The required torque according to the opening degree of the accelerator pedal may be less than or excessive to target torque required to exit drift driving.

Accordingly, in the present invention, the target torque of the front wheel motor required for exiting drift driving can be accurately set by multiplying the required torque having a preset value by the sensitivity factor to obtain the target torque.

The above-described sensitivity factor SF is a factor for changing a magnitude of the required torque according to the opening degree of the accelerator pedal, and a relationship between the opening degree of the accelerator pedal and the sensitivity factor SF may be implemented in a form of a linear function as shown in reference numeral 152b, but it should be noted that it is not necessarily limited to only the linear function.

The torque calculating unit <NUM> may calculate a target torque of the front wheel motor <NUM>, by extracting the sensitivity factor SF according to the opening degree of the accelerator pedal with reference to the relationship 152b between the opening degree of the accelerator pedal and the corresponding sensitivity factor, and multiplying the extracted sensitivity factor SF by the required torque described above using a multiplier 152c.

Thereafter, the torque calculating unit <NUM> may calculate the target torque according to the cumulative count value K by multiplying the calculated target torque by the weight factor WF according to the cumulative count value.

Here, the weight factor WF may have a value, proportional to the cumulative count value to reach the target torque at a point in time at which the cumulative count value K becomes a second cumulative count value K2, greater than the first cumulative count value K1.

It should be noted that the relationship between the cumulative count value K and the weight factor WF may be implemented in a form of a linear function as shown in a reference numeral 152a, but is not necessarily limited to the linear function.

The torque calculating unit <NUM> may obtain a target torque according to the cumulative count value K, by multiplying the weight factor WF corresponding to the cumulative count value K and the target torque using a multiplier 152c with reference to the relationship 152a between the cumulative count value K and the weight factor WF.

Also, according to an embodiment of the present invention, the torque calculating apparatus <NUM> may further include a low-pass filter 152d to remove noise of the target torque according to the cumulative count value K.

Meanwhile, <FIG> are views for comparing and illustrating a motor torque during normal driving and drift driving and during exiting drift driving, <FIG> illustrates torque applied to the front wheel motor <NUM> and the rear wheel motor <NUM> during normal driving, <FIG> illustrates torque applied to the front wheel motor <NUM> and the rear wheel motor <NUM> during drift driving, and <FIG> illustrates torque applied to the front wheel motor <NUM> and the rear wheel motor <NUM> during exiting drift driving. In addition, a reference numeral <NUM> may denote a total required torque according to the opening degree of the accelerator pedal, a reference numeral <NUM> may denote torque applied to the rear wheel motor <NUM> among the total required torque, and a reference numeral <NUM> may denote torque applied to the front wheel motor <NUM> among the total required torque.

As illustrated in <FIG>, in normal driving, the total required torque <NUM> according to the opening degree of the accelerator pedal is distributed to the front wheel motor <NUM> and the rear wheel motor <NUM> according to the opening degree of the accelerator pedal at a constant ratio and applied thereto.

As illustrated in <FIG>, during drift driving, torque is applied only to the rear wheel motor <NUM> according to the opening degree of the accelerator pedal, whereas torque is not applied to the front wheel motor <NUM>. Thereby, slip can be induced in the rear wheel <NUM>, and drift driving may be performed.

As illustrated in <FIG>, when exiting drift driving, it can be seen that the torque <NUM> also gradually increases in the front wheel motor <NUM> from a point in time at which the cumulative count value K is a first cumulative count value K1.

Meanwhile, <FIG> is a diagram illustrating actually measured data according to an embodiment of the present invention. In <FIG>, a reference numeral <NUM> may denote torque of the rear wheel motor <NUM>, a reference numeral <NUM> may denote torque of the front wheel motor <NUM>, a reference numeral <NUM> may denote a steering angle, a reference numeral <NUM> may denote an opening degree of the accelerator pedal, and a reference numeral <NUM> may denote acceleration in a longitudinal direction.

As illustrated in <FIG>, when exiting drift driving, it can be seen that acceleration <NUM> in a longitudinal direction also increases as the torque <NUM> of the front wheel motor <NUM> gradually increases from a point in time at which the cumulative count value K is a first cumulative count value K1, and both the front wheel motor <NUM> and the rear wheel motor <NUM> are driven.

As described above, according to an embodiment of the present invention, in a vehicle during drift driving, the driver's intention to exit drift driving may be determined based on the opening degree and the steering angle of the accelerator pedal, and thereafter, by driving the front wheel motor by calculating the target torque of the front wheel motor based on the opening degree of the accelerator pedal, and it is possible to exit drift driving.

In addition, according to an embodiment of the present invention, when calculating the above-described target torque, the target torque of the front wheel motor required for exiting drift driving may be accurately set by multiplying a magnitude of the preset required torque according to the opening degree of the accelerator pedal by the sensitivity factor according to the opening degree of the accelerator pedal.

In addition, according to an embodiment of the present invention, by multiplying the above-described target torque by a weight factor according to the cumulative count value, the target torque applied to the front wheel motor may be smoothly increased, thereby preventing non-linear behavior of the vehicle due to abrupt torque application.

<FIG> is a flowchart illustrating a method of calculating torque of a vehicle according to an embodiment of the present invention.

Hereinafter, a method (S600) of calculating the torque of a vehicle according to an embodiment of the present invention will be illustrated with reference to <FIG>.

Referring to <FIG>, the method (S600) of calculating torque of a vehicle according to an embodiment of the present invention may be initiated by the operation of determining a driver's intention for exiting drift driving based on an opening degree of an accelerator pedal and a steering angle in the determination unit <NUM> (S601).

According to an embodiment of the present invention, the determination unit <NUM> may determine that there is an intention to exit drift driving when the steering angle is less than a first reference steering angle, and the opening degree of the accelerator pedal is greater than a first reference opening degree.

Specifically, as described above, the determination unit <NUM> may count a time at which the steering angle is less than a first reference steering angle and the opening degree of the accelerator pedal is greater than a first reference opening degree and cumulate the same, and in this case, when a cumulative count value K is greater than or equal to a first cumulative count value K1, the determination unit <NUM> may determine that there is an intention for exiting drift driving.

Meanwhile, according to the embodiment of the present invention, as described above, the determination unit <NUM> may count a time at which the steering angle is less than a first reference steering angle and the opening degree of the accelerator pedal is greater than a reference opening degree, and reset a cumulative count value K when the steering angle is greater than a second reference steering angle.

Next, when a driver's intention to exit drift driving is determined, the torque calculating unit <NUM> may calculate target torque of a front wheel motor <NUM> based on the opening degree of the accelerator pedal (S602).

According to an embodiment of the present invention, the torque calculating unit <NUM> may calculate the target torque of the front wheel motor <NUM> by multiplying the required torque according to the opening degree of the accelerator pedal by a sensitivity factor SF according to the opening degree of the accelerator pedal and a weight factor WF according to the cumulative count value K.

Specifically, the torque calculating unit <NUM> may extract the sensitivity factor SF according to the opening degree of the accelerator pedal with reference to a relationship 152b between the opening degree of the accelerator pedal and the corresponding sensitivity factor, and may calculate the target torque of the front wheel motor <NUM>, by multiplying the extracted sensitivity factor SF by the required torque described above using a multiplier 152c as described above.

Thereafter, the torque calculating unit <NUM> may calculate the target torque according to the cumulative count value K by multiplying the calculated target torque by a weight factor WF according to the cumulative count value, where the weight factor WF may have a value proportional to the cumulative count value to reach the target torque when the cumulative count value K becomes a second cumulative count value K2, greater than the first cumulative count value K1, as described above.

Finally, the motor controller <NUM> may drive the front wheel motor <NUM> according to the calculated target torque (S603).

As described above, according to an embodiment of the present invention, the driver's intention to exit drift driving may be determined based on the opening degree and the steering angle of the accelerator pedal in a vehicle during drift driving, and thereafter, the front wheel motor may be driven by calculating the target torque of the front wheel motor based on the opening degree of the accelerator pedal, such that it is possible to exit drift driving.

In addition, according to an embodiment of the present invention, when calculating the above-described target torque, a magnitude of the required torque preset according to the opening degree of the accelerator pedal may be multiplied by a sensitivity factor according to the opening degree of the accelerator pedal, thereby accurately setting the target torque of the front wheel motor required for exiting drift driving.

In addition, according to an embodiment of the present invention, the target torque applied to the front wheel motor may be smoothly increased by multiplying the above-described target torque by a weight factor according to the cumulative count value, thereby preventing nonlinear behavior of the vehicle due to abrupt torque application.

Meanwhile, <FIG> is a block diagram of torque calculating apparatus according to an embodiment of the present invention, and is a block diagram applicable to the torque calculating apparatus shown in <FIG>.

As illustrated in <FIG>, the torque calculating apparatus <NUM> may include an input interface <NUM>, an output interface <NUM>, a processor <NUM>, and a memory <NUM>, and the input interface <NUM>, the output interface <NUM>, the processor <NUM>, and the memory <NUM> may be interconnected via a system bus <NUM>.

In an embodiment of the present invention, the memory <NUM> may be used to store a program, an instruction or a code stored in the memory <NUM>, and the processor <NUM> may perform a program, a command, or a code stored in the memory <NUM>, control the input interface <NUM> to receive a signal, and control the output interface <NUM> to transmit the signal. The memory <NUM> described above may include read-only memory and random access memory, and may provide instructions and data to the processor <NUM>.

In an embodiment of the present invention, the processor <NUM> may be a Central Processing Unit (CPU), and may be another general-purpose processor, a Digital Signal Processor (DSP), or an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other programmable logic device, discrete gate or transistor logic device, discrete hardware component, or the like. A general-purpose processor may be a microprocessor, or the processor may be any conventional processor, or the like. The above-described processor <NUM> may perform the operation of the above-described torque calculating apparatus when executing the program, the instruction or the code stored in the memory <NUM>.

In one implementation process, the method of <FIG> may be achieved by an integrated logic circuit of hardware in the processor <NUM> or an instruction in a form of software. The contents of the method disclosed in relation to the embodiment of the present invention may be implemented to be performed and completed by a hardware processor, or may be performed and completed by a combination of hardware and software modules of the processor. The software module may be disposed in a storage medium such as random access memory, flash memory, read-only memory, programmable read-only memory or electrically erasable programmable memory, registers, and the like. The corresponding storage medium is located in the memory <NUM>, and the processor <NUM> reads information from the memory <NUM> and implements the contents of the above-described method in combination with hardware. In order to avoid duplication, detailed descriptions thereof will be omitted herein.

As set forth above, according to an embodiment of the present invention, in a vehicle in drift driving, a driver's intention to exit drift driving may be determined based on an opening degree of an accelerator pedal and a steering angle, and thereafter, by calculating target torque of a front wheel motor based on the opening degree of the accelerator pedal and driving the front wheel motor, it is possible to exit drift driving.

In addition, according to an embodiment of the present invention, when calculating the above-described target torque, the target torque of the front wheel motor required for exiting drift driving may be accurately set by multiplying a predetermined required torque according to the opening degree of the accelerator pedal by a sensitivity factor according to the opening degree of the accelerator pedal.

In addition, according to an embodiment of the present invention, the target torque applied to the front wheel motor may be smoothly increased by multiplying the above-described target torque by a weight factor according to the cumulative count value, thereby preventing non-linear behavior of the vehicle due to abrupt torque application.

Claim 1:
An apparatus (<NUM>) for calculating torque of a vehicle for exiting drift driving, the apparatus comprising:
a processor (<NUM>); and
a non-transitory computer-readable storage medium (<NUM>) storing a program which, when executed by the processor (<NUM>), causes the processor (<NUM>) to perform:
determining a driver's intention to exit drift driving based on an opening degree of an accelerator pedal and a steering angle, and
calculating target torque of a front wheel motor (<NUM>) based on the opening degree of the accelerator pedal when the intention to exit drift driving is determined,
wherein the determining a driver's intention comprises:
counting a time at which the steering angle is less than a first reference steering angle, and the opening degree of the accelerator pedal is greater than a first reference opening degree and cumulate the same, and
when a cumulative count value (K) is greater than or equal to a preset first cumulative count value (K1), determining that there is an intention to exit drift driving.