KR102471005B1 - Method and apparatus for ramp and weight estimation - Google Patents

Abstract

A ramp and weight estimation method according to an embodiment of the present invention includes estimating engine acceleration by dividing a driving force by an empty vehicle weight; estimating vehicle acceleration based on the engine acceleration and wheel acceleration; estimating gradient acceleration based on the measured acceleration and the estimated vehicle acceleration; calculating a weight based on the estimated gradient acceleration; calculating a current mass based on the engine acceleration, the estimated acceleration, and the unloaded vehicle weight; and determining a final estimated mass based on the calculated current mass.

Description

Method and apparatus for ramp and weight estimation {Method and apparatus for ramp and weight estimation}

The present invention relates to a method and apparatus for estimating a slope and weight.

The prior art vehicle state estimation method may estimate the vehicle state based on values measured by an engine installed in the vehicle, a longitudinal acceleration sensor, and a wheel speed sensor.

1 is a view showing a vehicle state according to the prior art.

Referring to FIG. 1 , the vehicle state estimation method of the prior art is a method of estimating a slope, and wheel acceleration may be estimated by differentiating a wheel speed 50 of a vehicle 10 . Through this, the difference between the measured acceleration 30 of the vehicle and the wheel acceleration can be estimated as a slope.

In addition, the vehicle state estimation method of the prior art is a method of estimating weight and can estimate acceleration using a vehicle engine torque value. remind. The estimated acceleration may be engine acceleration. Through this, the estimated weight can be estimated by multiplying the basic weight of the vehicle and the engine acceleration/wheel acceleration.

Since the existing weight estimation logic according to the vehicle state estimation technique of the prior art uses the engine torque value, it is estimated only when the accelerator pedal is depressed. For this reason, there is a problem in that an error increases on a road without slope correction because estimation is frequently performed on an uphill.

An object of the present invention is to provide a method and apparatus for estimating a slope and weight having a slope and weight independent estimation algorithm.

The tasks of the present invention are not limited to the tasks mentioned above, and other tasks not mentioned will be clearly understood by those skilled in the art from the description below.

A ramp and weight estimation method according to an embodiment of the present invention includes estimating engine acceleration by dividing a driving force by an empty vehicle weight; estimating vehicle acceleration based on the engine acceleration and wheel acceleration; estimating gradient acceleration based on the measured acceleration and the estimated vehicle acceleration; calculating a weight based on the estimated gradient acceleration; calculating a current mass based on the engine acceleration, the estimated acceleration, and the unloaded vehicle weight; and determining a final estimated mass based on the calculated current mass.

According to an embodiment, the estimating engine acceleration may include correcting engine torque based on a first low pass filter (LPF); correcting an engine speed based on the second LPF; vehicle gear ratio calculation step; calculating a driving torque based on the engine torque, the engine speed, the vehicle gear ratio, and a third LPF; and calculating longitudinal force and engine acceleration based on the driving torque.

Depending on the embodiment, the vehicle acceleration may be estimated based on the vehicle acceleration estimating tire radius, wheel driving torque, braking torque, aerodynamic stability, and rolling resistance.

Depending on the embodiment, in the estimating the gradient acceleration, the gradient acceleration may be estimated based on the wheel acceleration, the gradient acceleration, and a weight offset.

Depending on the embodiment, the gradient acceleration may be estimated based on the measured acceleration, the estimated acceleration, and the weight offset.

According to an embodiment, the gradient acceleration estimating step may include a starting determination step; stopping decision step; flatness judgment step; and an offset fixing condition step.

According to an embodiment, the weight calculation step may include a step of excluding rapid acceleration/deceleration stop driving; Excluding turning situations; Steep slope exclusion step; and slow and fast exclusion steps.

According to an embodiment, the current mass calculating step may calculate the current mass based on Equation 7 below.

According to an embodiment, the step of determining the final estimated mass may include a mass calculation step; mass difference calculation step; calculating filter coefficients according to weights; and filtering the mass estimation value.

An apparatus for estimating ramp and weight according to an embodiment of the present invention includes an engine acceleration estimating unit for estimating engine acceleration by dividing a driving force by an empty vehicle weight; a vehicle acceleration estimation unit estimating a vehicle acceleration based on the engine acceleration and the wheel acceleration; a gradient acceleration estimation unit estimating a gradient acceleration based on the measured acceleration and the estimated vehicle acceleration; a weight calculating unit calculating weights based on the estimated gradient acceleration; a current mass calculator configured to calculate a current mass based on the engine acceleration, the estimated acceleration, and the unloaded vehicle weight; and a final estimated mass determiner configured to determine a final estimated mass based on the calculated current mass.

According to an embodiment, the engine acceleration estimation unit corrects engine torque based on a first LPF (Low Pass Filter), corrects engine speed based on a second LPF, calculates a vehicle gear ratio, and calculates the engine torque and the engine speed. Driving torque may be calculated based on the speed, the vehicle gear ratio, and the third LPF, and longitudinal force and engine acceleration may be calculated based on the driving torque.

Depending on the embodiment, the vehicle acceleration estimator may estimate the gradient acceleration based on the wheel acceleration, the gradient acceleration, and the weight offset.

Depending on the embodiment, the gradient acceleration may be estimated based on the gradient acceleration, the wheel acceleration, the gradient acceleration, and a weight offset.

Depending on the embodiment, the gradient acceleration may be estimated based on the measured acceleration, the estimated acceleration, and the weight offset.

Depending on the embodiment, the gradient acceleration estimator may determine a slope based on a start determination condition, a stop determination condition, a flat surface determination condition, and an offset fixed condition.

Depending on the embodiment, the weight calculation unit may perform a step of excluding sudden acceleration/deceleration stop running, a step of excluding a turning situation, a step of excluding a steep slope, and a step of excluding low speed and high speed.

According to an embodiment, the current mass calculation unit may calculate the current mass based on Equation 7 below.

According to an embodiment, the final estimated mass determining unit calculates a current mass, calculates a difference between the current mass and the estimated mass, calculates a filter coefficient according to a weight, and filters the estimated mass value based on the estimated mass and the mass difference. can do.

The above aspects of the present invention are only some of the preferred embodiments of the present invention, and various embodiments in which the technical features of the present invention are reflected are detailed descriptions of the present invention to be detailed below by those skilled in the art. It can be derived and understood based on.

Effects of the method and apparatus for estimating the slope and weight according to the present invention are described as follows.

It has the advantage of reducing errors due to weight estimation on uphill and downhill by reflecting the slope and weight independent estimation algorithm.

The effects obtainable in the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the description below. will be.

The accompanying drawings are provided to aid understanding of the present invention, and provide embodiments of the present invention together with a detailed description. However, the technical features of the present invention are not limited to specific drawings, and features disclosed in each drawing may be combined with each other to form a new embodiment.
1 is a view showing a vehicle state according to the prior art.
2 is a block diagram of a ramp and weight estimation device according to an embodiment of the present invention.
3 is a diagram illustrating a mass estimation method according to an embodiment of the present invention.
4 is a diagram illustrating an engine acceleration estimation method according to an embodiment of the present invention.
5 is a diagram illustrating gradient acceleration data according to a method for estimating gradient acceleration according to an embodiment of the present invention.
6 is a diagram illustrating a method for correcting a slope according to an embodiment of the present invention.
7 is a diagram illustrating data of a correction gradient acceleration calculation and a mass estimation correction method according to an embodiment of the present invention.
8 is a flowchart illustrating a method for determining a final estimated mass according to an embodiment of the present invention.
9 is a diagram illustrating a sequence of determining a weight offset and a slope according to an embodiment of the present invention.
10 is a diagram showing a simulation result of a real vehicle test on a flat surface according to an embodiment of the present invention.
11 is a diagram showing a simulation result of a real vehicle test on a ramp according to an embodiment of the present invention.

Hereinafter, an apparatus and various methods to which embodiments of the present invention are applied will be described in more detail with reference to the drawings. The suffixes "module" and "unit" for components used in the following description are given or used together in consideration of ease of writing the specification, and do not have meanings or roles that are distinct from each other by themselves.

In the description of the embodiment, in the case where it is described as being disposed in "above (above) or below (below)", "before (front) or after (rear)" of each component, "upper (above) or lower (below)" (below)" and "before (front) or after (rear)" include both arrangements in which two elements are in direct contact with each other or one or more other elements are disposed between the two elements.

Also, terms such as first, second, A, B, (a), and (b) may be used in describing the components of the present invention. These terms are only used to distinguish the component from other components, and the nature, order, or order of the corresponding component is not limited by the term. When an element is described as being “connected,” “coupled to,” or “connected” to another element, that element is or may be directly connected to the other element, but there is another element between the elements. It will be understood that elements may be “connected”, “coupled” or “connected”.

In addition, terms such as "include", "comprise" or "have" described above mean that the corresponding component may be inherent unless otherwise stated, excluding other components. It should be construed as being able to further include other components. All terms, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs, unless defined otherwise. Commonly used terms, such as terms defined in a dictionary, should be interpreted as consistent with the meaning in the context of the related art, and unless explicitly defined in the present invention, they are not interpreted in an ideal or excessively formal meaning.

2 is a block diagram of a ramp and weight estimation device according to an embodiment of the present invention.

Referring to FIG. 2 , the ramp and weight estimation apparatus of the present invention includes an engine acceleration estimation unit 100, a vehicle acceleration estimation unit 120, a gradient acceleration estimation unit 130, a weight calculation unit 140, and a current mass calculation unit 150. ), and a final estimated mass determination unit 160.

The engine acceleration estimator 100 may estimate the driving force as the tolerance increment value as the engine acceleration.

The engine acceleration estimator 100 may receive engine torque information and output corrected engine torque by applying a first low pass filter (LPF) to the received engine torque information.

The engine acceleration estimator 100 may receive engine speed information and output a corrected engine speed by applying a second low pass filter (LPF) to the received engine speed information.

The engine acceleration estimator 100 may calculate the gear ratio by Equation 1 below. The second LPF is as shown in Equation 1.

[Equation 1]

When gear ratio = final reduction ratio x gear ratio x efficiency, the gear ratio is the gear ratio for each gear stage, and the final reduction ratio is the gear ratio of the final reduction device.

The engine acceleration estimator 100 may receive gear stage information and output a value obtained by multiplying the final reduction ratio, gear ratio, and efficiency as a gear ratio based on the received gear stage information.

The engine acceleration estimation unit 100 may calculate a driving torque by applying a third LPF to the corrected engine torque, the corrected engine speed, and the calculated vehicle gear ratio. The engine acceleration estimator 100 may calculate the driving torque by Equation 2 below. The third LPF is equal to Equation 2.

[Equation 2]

Drive torque = engine torque x gear ratio - engine inertia torque

In this case, the engine inertia torque is a value obtained by multiplying an acceleration estimated based on wheel speed by a moment value.

The engine acceleration estimator 100 may calculate the longitudinal force and the engine acceleration based on the braking pressure information, the wheel acceleration 50 information, and the driving torque information.

The engine acceleration estimator 100 may calculate the tire longitudinal force by Equation 3 below.

[Equation 3]

When tire longitudinal force = (average braking torque - wheel driving torque) / wheel radius + resistance due to wheel acceleration, the average braking torque is the average of the braking torque of four wheels arranged in the vehicle, and the wheel driving torque is the product of the driving torque and the gear ratio.

The vehicle acceleration estimator 120 may receive measurement acceleration 30 information from an acceleration sensor. At this time, the measured acceleration 30 information may have a different value from the actual vehicle acceleration due to the inclusion of vehicle pitch and acceleration terms. The measured acceleration 30 may be a value measured using a gyro sensor or the like.

The vehicle acceleration estimator 120 may estimate the estimated acceleration based on the engine torque. At this time, the estimated acceleration may have the same tendency as the measured acceleration 30 during vehicle acceleration. Accordingly, the vehicle acceleration estimator 120 may estimate a wheel speed reflecting the actual behavior of the vehicle and estimate acceleration based on the estimated wheel speed. The vehicle acceleration estimator 120 may estimate the vehicle acceleration based on the tire radius, wheel driving torque, braking torque, aerodynamic stability, and rolling resistance.

The vehicle acceleration estimator 120 may estimate the vehicle acceleration by Equation 4 below.

[Equation 4]

Estimated acceleration based on engine torque

= {r _wheel ·( T _eng - T _brake ) - (F _aero + F _rolling )}/M

= vehicle actual acceleration (wheel acceleration) + incline acceleration

Here, r _wheel is the radius of the tire, T _eng is the wheel driving torque, T _brake is the braking torque, _Faero is the aerodynamic resistance, F _rolling is the rolling resistance, and M is the weight of the vehicle.

The gradient acceleration estimation unit 130 may calculate the difference between the measured acceleration and the estimated acceleration. The gradient acceleration estimation unit 130 may estimate the gradient acceleration based on the wheel acceleration, the gradient acceleration, and the weight offset.

The gradient acceleration estimator 130 may estimate the measured acceleration by Equation 5 below.

[Equation 5]

Measured acceleration (sensor) = Estimated acceleration based on engine torque

= r _wheel ·( T _eng - T _brake ) / M - (F _aero + F _rolling )/M

= vehicle actual acceleration (wheel acceleration) + slope acceleration + weight offset

= a _x,wheel + g sin( Θ ) + ax _offset

At this time, r _wheel is the radius of the tire, T _eng is the wheel driving torque, T _brake is the braking torque, F _aero is the aerodynamic resistance, F _rolling is the rolling resistance, and the _{ax, wheel} is the wheel acceleration , g sin( Θ ) is the gradient acceleration, ax _offset is the weight offset, and M is the weight of the vehicle. In this case, the wheel acceleration may be the actual acceleration of the vehicle.

The gradient acceleration of Equation 5 can be calculated by Equation 6 below.

[Equation 6]

Incline acceleration = measured acceleration (sensor) - estimated acceleration (wheel acceleration) - weight offset

At this time, the gradient may be atan (gradient acceleration/g) ≒ gradient acceleration x 0.1.

Therefore, the gradient acceleration estimator 130 may estimate based on the measured acceleration, the estimated acceleration, and the weight offset.

The weight calculator 140 may reflect an optimal estimation state through a map for each condition of the vehicle state. The vehicle state may include a deceleration and constant speed excluding state, a steep slope excluding state, a rapid acceleration excluding state, and a low-speed and high-speed excluding state.

For example, in a state where deceleration and constant speed driving are excluded, the weight may be increased from 0 to 1 in a section where the model acceleration is 0.5 m/s ² to 2 m/s ² .

For example, in a state where deceleration and constant speed driving are excluded, the weight may be increased from 0 to 1 in a section where the wheel acceleration 50 is 0.3 m/s ² to 1 m/s ² .

For example, when a steep slope is excluded, the weight may be reduced from 1 to 0 in a section where the slope is 4% to 6%.

For example, in the case of a sudden acceleration situation excluded state, the weight may be reduced from 1 to 0 in a section where the driving force change amount is 150 n to 350 n.

For example, in the case of the low speed and high speed exclusion states, the weight may be increased from 0 to 1 in a section where the vehicle speed is 20 kph to 40 kph. In addition, in a section where the vehicle speed is 90 kph to 120 kph, the weight is can be reduced from 1 to 0.

For example, the weight may be increased from 0 to 1 in a section where the driving force is 800n to 1160n.

The current mass calculation unit 150 may estimate the current mass by Equation 7 below.

[Equation 7]

Current Mass = (Engine Acceleration / Actual Acceleration) x Unladen Weight

In this case, the empty vehicle weight may be the weight of a vehicle not loaded with people or luggage.

In this case, the actual acceleration may be the sum of the estimated acceleration and the corrected gradient acceleration.

The final estimated mass determiner 160 may determine the final estimated mass based on weight-based filtering.

The final estimated mass determination unit 160 may calculate the mass by Equation 8 below.

[Equation 8]

Current Mass = Estimated Force / Estimated Acceleration

In this case, the estimated force may be an absolute value of a difference between engine force and brake force.

The final estimated mass determination unit 160 may calculate the mass difference according to Equation 9 below.

[Equation 9]

Mass Difference = Current Mass - Estimated Mass

The final estimated mass determiner 160 may calculate filter coefficients according to weights.

The final estimated mass determination unit 160 may calculate the estimated mass by Equation 10 below.

[Equation 10]

Estimated Mass = Estimated Mass + Weight x Mass Difference

In this case, the weight is a value obtained by calculating filter coefficients calculated based on the driving state of the vehicle.

3 is a diagram illustrating a mass estimation method according to an embodiment of the present invention.

Referring to FIG. 3, the mass estimation method of the present invention can be estimated using the basic dynamics equation F = ma.

FIG. 3(a) is a diagram illustrating a situation in which one driver is on board, and FIG. 3(b) is a diagram illustrating a situation in which an additional driver boards and luggage is loaded into the vehicle.

Referring to FIG. 3(b), when an additional person rides in the vehicle and the weight loading 80 is performed, additional engine torque may be required to generate the same acceleration as the vehicle of FIG. 3(a). At this time, the force applied to the vehicle of FIG. 3(b) can be estimated by F=ma. In this case, a may be acceleration required to maintain acceleration estimated based on wheel speed. F may be increased power due to additional engine torque.

At this time, the increased force can be estimated by Equation 11 below.

[Equation 11]

Estimated Power = (Engine Power - Brake Power) - Aerodynamic Resistance - Rolling Resistance

4 is a diagram illustrating an engine acceleration estimation method according to an embodiment of the present invention.

Referring to FIG. 4 , in the engine acceleration estimation method, the engine acceleration estimation unit 100 may receive engine torque and correct the engine torque (S110).

After the step S110, the engine acceleration estimation unit 100 may receive the engine speed and correct the engine speed (S120).

After the step S120, the engine acceleration estimator 100 may receive the gear stage and calculate a vehicle gear ratio (S130).

After the step S130, the engine acceleration estimator 100 may calculate the driving torque based on the corrected engine torque, the corrected engine speed, and the calculated vehicle gear ratio (S140).

After the step S140, the engine acceleration estimator 100 may calculate the longitudinal tire force based on the driving torque (S150).

5 is a diagram illustrating gradient acceleration data according to a method for estimating gradient acceleration according to an embodiment of the present invention.

5(a) is data showing a case where the slope is an upper slope,

Referring to FIG. 5(a) , when the slope of the road is an upward slope, the acceleration measured by the sensor may be greater than the acceleration estimated by the wheel acceleration 50 and the engine acceleration.

Therefore, since the gradient acceleration is the difference between the measured acceleration and the estimated acceleration, when the gradient of the road is an upward gradient, the gradient acceleration may act in a downward gradient direction.

Referring to FIG. 5(b) , when the slope of the road is downward, the acceleration measured by the sensor may be smaller than the acceleration estimated by the wheel acceleration 50 and the engine acceleration.

Therefore, since the gradient acceleration is the difference between the measured acceleration and the estimated acceleration, when the gradient of the road is downward, the gradient acceleration may act in an upward direction.

6 is a diagram illustrating a method for correcting a slope according to an embodiment of the present invention.

Referring to FIG. 6(a), the gradient acceleration estimator 130 may calculate the difference between the measured acceleration and the estimated acceleration.

The gradient acceleration estimator 130 may estimate the measured acceleration by Equation 5 above.

Referring to FIG. 6( b ), as an offset weight is loaded on the vehicle, a pitch 70 of the vehicle may occur due to the weight loading of the object.

In addition, according to the generation of the pitch, the acceleration sensor of the vehicle is tilted, and thus an offset may occur.

At this time, the slope estimation unit 130 may calculate the weight offset by Equation 12 below, assuming that the vehicle has stopped on a flat surface.

[Equation 12]

Incline acceleration = 0 = measured acceleration (sensor) - estimated acceleration (wheel acceleration) - weight offset

Weight offset = measured acceleration (sensor) - estimated acceleration (wheel acceleration)

Through this, the slope estimation unit 130 may calculate the corrected slope acceleration by calculating the weight offset when the vehicle is stopped.

7 is a diagram illustrating data of a correction gradient acceleration calculation and a mass estimation correction method according to an embodiment of the present invention.

Referring to FIG. 7, a wheel acceleration 50 sensor, an average value of gradient acceleration, and a reflected gradient acceleration are shown.

Through this, it is possible to calculate corrected gradient acceleration filtering data through the difference between the gradient acceleration 33 and the cumulative average of the gradient acceleration. The accuracy of the estimated current mass may be improved by reflecting the actual acceleration through the filtering data.

The current mass using the filtering data can be output by Equation 7 below.

[Equation 7]

Current Mass = (Engine Acceleration / Actual Acceleration) x Unladen Weight

In this case, the engine acceleration may be the actual acceleration + the additional acceleration due to the weight + the additional acceleration due to the slope, and the actual acceleration may be the estimated acceleration + the corrected gradient acceleration.

8 is a flowchart illustrating a method for determining a final estimated mass according to an embodiment of the present invention.

Referring to FIG. 8 , the final estimated mass determiner 160 may determine the final estimated mass based on weight-based filtering. The final estimated mass determination unit 160 may perform mass calculation (S210). At this time, the mass calculation may be performed by Equation 8 above.

After the step S210, the final estimated mass determination unit 160 may perform a mass difference calculation (S220). At this time, the mass difference calculation may be performed by Equation 9 above.

The final estimated mass determination unit 160 may calculate filter coefficients according to weights (S230).

After the step S330, the final estimated mass determination unit 160 may calculate the estimated mass by Equation 10 above (S240).

9 is a diagram illustrating a sequence of determining a weight offset and a slope according to an embodiment of the present invention.

Referring to FIG. 9 , the method for determining the weight offset and slope may determine whether the conditions for determining the start of the vehicle are satisfied (S310). The departure determination condition may be that the gear stage < 1 stage and the brake may be OFF.

If the above step S310 is satisfied, the starting Flag signal may be True (S315).

If the step S310 is not satisfied, it may be determined whether the vehicle stop determination condition is satisfied (S320). The vehicle stop determination condition may be speed < 1 m/s ² , and the start flag may be FALSE.

If the step S320 is satisfied, the stop offset can be calculated. In this case, the offset may be a cumulative average (S325).

If the step S320 is not satisfied, the gradient acceleration 33 may be calculated (S330).

After step 330, it may be determined whether the condition for determining the level of the vehicle is satisfied (S340). The flatness determination conditions may be speed > 1 m/s ² , gradient acceleration < flatland standard, and the offset fixed flag may be FALSE.

If step 340 is satisfied, a flatland offset can be calculated. At this time, the offset may be a cumulative average (S345).

If step 340 is not satisfied, an offset difference may be calculated (S350).

After the step S350, an offset fixing condition may be determined (S360). The offset fixing conditions may be offset difference < 0.05 m/s ² and flat land offset accumulation time > 5 seconds.

If the step S360 is satisfied, the corrected gradient acceleration = gradient acceleration - flat offset can be performed (S370).

If the step S360 is not satisfied, corrected gradient acceleration = gradient acceleration - stop offset can be performed (S380).

10 is a diagram showing a simulation result of a real vehicle test on a flat surface according to an embodiment of the present invention.

10 is a case in which the driver and 430 kg are loaded, and the basic weight of the vehicle is 1730 kg, driving on a flat surface according to an embodiment of the present invention.

10(a) is a diagram showing data according to time and speed. Referring to FIG. 10 (a), the speed is maintained constant, and there is a section in which the speed decreases between about 140 and 160 seconds.

10(b) is a diagram showing data according to time and reliability. Referring to FIG. 10(b), a section in which the computational reliability is 0 exists between the time range of 150 and about 550.

10(c) is a diagram showing data according to time and gradient acceleration. Referring to FIG. 10(c), the gradient acceleration range of 0 to 140 can be estimated as a flat area.

10(d) is a diagram showing data according to time and estimated mass. Referring to FIG. 11(d), a period of 160 seconds to 1000 seconds, in which the estimated mass according to the above calculation is higher than the actual mass, can be estimated as the high weight normal period.

11 is a diagram showing a simulation result of a real vehicle test on a ramp according to an embodiment of the present invention.

11 illustrates a case in which a vehicle drives on a ramp and a flat ground in combination, a driver and a passenger ride, and a basic weight of the vehicle is 1340 kg according to an embodiment of the present invention.

11(a) is a diagram showing data according to time and speed. Referring to FIG. 11(a), the vehicle speed changes, and the vehicle speed approaches zero after about 160 seconds.

11(b) is a diagram showing data according to time and reliability. Referring to FIG. 11(b), there is a section in which the calculation reliability is 0 in the section where the time is about 700 seconds.

11(c) is a diagram showing data according to time and gradient acceleration. Referring to FIG. 121c), it is possible to estimate a section with an upward slope of 5% in a section where the time is between 100 and 120 seconds and between 130 and 140 seconds.

11(d) is a diagram showing data according to time and estimated mass. Referring to FIG. 11(d), it is possible to estimate a section where the calculated mass is greater than the actual mass in a section where the time is about 700. Through this, it can be estimated that it is in a reset state due to the continuation of the stopped state.

The method according to the above-described embodiment may be produced as a program to be executed on a computer and stored in a computer-readable recording medium. Examples of the computer-readable recording medium include ROM, RAM, CD-ROM, and magnetic memory. Tape, floppy disk, optical input data storage system, etc. The computer-readable recording medium is distributed to computer systems connected through a network, so that computer-readable codes can be stored and executed in a distributed manner. In addition, functional programs, codes, and code segments for implementing the above-described method can be easily inferred by programmers in the technical field to which the embodiment belongs.

110: engine acceleration estimation unit
120: vehicle acceleration estimation unit
130: gradient acceleration estimation unit
140: weight calculation unit
150: current mass calculation unit
160: final estimated mass determination unit

Claims (19)

estimating engine acceleration by dividing the driving force by the vehicle weight;
estimating vehicle acceleration based on the engine acceleration and wheel acceleration;
estimating gradient acceleration based on the measured acceleration and the estimated vehicle acceleration;
calculating a weight based on the estimated gradient acceleration;
calculating a current mass based on the engine acceleration, the estimated acceleration, and the unloaded vehicle weight; and
Determining a final estimated mass based on the calculated current mass
including,
The final estimated mass determination step is
calculating the current mass;
calculating a difference between the current mass and the estimated mass;
calculating filter coefficients according to weights; and
and filtering a mass estimate based on the estimated mass and the mass difference. According to claim 1,
The engine acceleration estimation step is
Correcting engine torque based on a first LPF (Low Pass Filter);
correcting an engine speed based on the second LPF;
vehicle gear ratio calculation step;
calculating a driving torque based on the engine torque, the engine speed, the vehicle gear ratio, and a third LPF; and
A method for estimating a slope and a weight comprising calculating a longitudinal force and an engine acceleration based on the driving torque. According to claim 1,
The vehicle acceleration estimation step is
A ramp and weight estimation method for estimating the vehicle acceleration based on tire radius, wheel driving torque, braking torque, aerodynamic stability and rolling resistance. According to claim 1,
The gradient acceleration estimation step is
A ramp and weight estimation method for estimating a slope acceleration based on the wheel acceleration, the slope acceleration, and a weight offset. According to claim 4,
The gradient acceleration is
A method of estimating a slope and weight based on the measured acceleration, the estimated acceleration, and the weight offset. According to claim 1,
The gradient acceleration estimation step is
Departure judgment step;
stopping decision step;
flatness judgment step; and
A ramp and weight estimation method including an offset fixed condition step. According to claim 1,
The weight calculation step is
a step excluding rapid acceleration/deceleration stop driving;
Excluding turning situations;
Steep slope exclusion step; and
A method for estimating a ramp and weight including at least one of low speed and high speed exclusion steps. According to claim 1,
The current mass calculation step is
A ramp and weight estimation method for calculating the current mass based on Equation 7 below.
[Equation 7]
Current Mass = (Engine Acceleration / Actual Acceleration) x Unladen Weight
(actual acceleration: estimated acceleration + corrected gradient acceleration) delete A computer-readable recording medium in which a program for realizing the method for estimating a slope and a weight according to any one of claims 1 to 8 is recorded. an engine acceleration estimator for estimating engine acceleration by dividing the driving force by the empty vehicle weight;
a vehicle acceleration estimation unit estimating a vehicle acceleration based on the engine acceleration and the wheel acceleration;
a gradient acceleration estimation unit estimating a gradient acceleration based on the measured acceleration and the estimated vehicle acceleration;
a weight calculating unit calculating weights based on the estimated gradient acceleration;
a current mass calculator configured to calculate a current mass based on the engine acceleration, the estimated acceleration, and the unloaded vehicle weight; and
A final estimated mass determining unit for determining a final estimated mass based on the calculated current mass
including,
The final estimated mass determination unit
Calculate the current mass,
Calculate a difference between the current mass and the estimated mass;
Calculate the filter coefficient according to the weight,
A ramp and weight estimation device for filtering a mass estimation value based on the estimated mass and the mass difference. According to claim 11,
The engine acceleration estimation unit
Correcting engine torque based on a first LPF (Low Pass Filter);
correcting the engine speed based on the second LPF;
Calculate vehicle gear ratio,
calculating a drive torque based on the engine torque, the engine speed, the vehicle gear ratio, and a third LPF;
A ramp and weight estimation device for calculating longitudinal force and engine acceleration based on the driving torque. According to claim 11,
The vehicle acceleration estimation unit
A ramp and weight estimation device for estimating the vehicle acceleration based on tire radius, wheel driving torque, braking torque, aerodynamic stability and rolling resistance. According to claim 11,
The gradient acceleration estimation unit
A ramp and weight estimation device for estimating a slope acceleration based on the wheel acceleration, the slope acceleration, and a weight offset. According to claim 11,
The gradient acceleration estimation unit
Estimating the gradient acceleration based on the measured acceleration, the estimated acceleration, and the weight offset
Ramp and weight estimator. According to claim 11,
The gradient acceleration estimation unit
A ramp and weight estimation device that determines a ramp based on a start determination condition, a stop determination condition, a level determination condition, and an offset fixed condition. According to claim 11,
The weight calculator
A ramp and weight estimation device that performs at least one of a rapid acceleration/deceleration stop driving exclusion step, a turning situation exclusion step, a steep slope exclusion step, and a low speed and high speed exclusion step. According to claim 11,
The current mass calculation unit
A ramp and weight estimation device that calculates the current mass based on Equation 7 below.
[Equation 7]
Current Mass = (Engine Acceleration / Actual Acceleration) x Unladen Weight
(actual acceleration: estimated acceleration + corrected gradient acceleration) delete

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