KR20030080926A - System and method to measure engine torque of driving vehicle - Google Patents

Abstract

PURPOSE: A system and a method for measuring engine torque of a running vehicle are provided to stabilize a state of a vehicle by allowing a user to easily measure performance of an engine using various devices installed in an engine. CONSTITUTION: An engine torque measuring system includes a speed sensor(10), an engine R.P.M measuring sensor(20), an accelerator meter(30), a weather measuring device and a data collecting device(40). The speed sensor(10) is installed at an outer portion of a door so as to measure a speed of a running vehicle. The engine R.P.M measuring sensor(20) is engaged with a wire positioned adjacent to an ignition coil of an engine so as to measure a pulse, thereby measuring an engine R.P.M. The weather measuring device is provided at an outer portion of the vehicle. The data collecting device(40) collects information transferred from the speed sensor(10), engine R.P.M measuring sensor(20), and accelerator meter(30).

Description

Engine Torque Measurement System and Method for Real Vehicles {SYSTEM AND METHOD TO MEASURE ENGINE TORQUE OF DRIVING VEHICLE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and a system for measuring torque output from an engine of a vehicle to a transmission, that is, engine torque, and more particularly, a speed sensor for measuring a driving vehicle speed, a sensor for measuring an engine speed, and an acceleration of the vehicle. Accelerometer for measuring the weather and the weather measurement device for measuring the weather conditions of the road and the information from the speed sensor, the rotation speed measurement sensor and the accelerometer collect and analyze the real-time weather information of the meteorological measurement device to the standard atmosphere The present invention relates to a method and system for measuring engine torque of a running vehicle, comprising a data collecting device for calculating a standard value corrected in a state.

In general, the resistance received by a vehicle during driving is rolling resistance (Rr), air resistance (Ra), gradient resistance (Rg), and acceleration resistance (Ri), and the sum of these resistances is referred to as total driving resistance. The pre-run resistance is expressed by Equation 1 below.

Rt = Rr + Ra + Rg + Ri

In the above Equation 1, when both Rg and Ri are 0, it is called a flat constant speed running resistance and means a resistance received when the flat road is driven at a constant speed. In addition, the case where only Rg is 0 is called a flat acceleration driving resistance, and it means the state which accelerates a flat path.

In the above, rolling resistance (Rr) refers to the resistance between the tire and the road surface when the vehicle is traveling on the road. The rolling resistance varies according to the condition of the road, the type and structure of the tire, the speed of the vehicle and the air pressure of the tire.Typically, when the total weight of the vehicle is W and the rolling resistance coefficient is μ _r , the following equation 2 It is expressed as

Rr = μ _r and W

Air resistance (Ra) is a resistance due to friction with the air received by the vehicle when driving, the shape resistance according to the shape of the vehicle body, the induction resistance that makes the vehicle feel lifted at high speed, and the frictional resistance caused by the viscosity with the air For example, turbulence is formed by various irregularities on the surface of the vehicle body, and surface resistance generated and internal resistance caused by air introduced into the vehicle. The air resistance is proportional to the square of the vehicle speed, and when the front projection area of the car is A (㎡), the running speed is V (km / hr), and the air resistance coefficient is μ _a , it is expressed as Equation 3 below.

Ra = μ _a-A and V ²

Gradient resistance (Rg) is a resistance that is physically received when driving on hills or sloped roads. As shown in Fig. 1, the gradient resistance received when a vehicle having a total weight of W travels a sloped road having a draft angle of θ is expressed as in Equation 4 below. As can be seen from the figure, the total weight W is divided by the component W 'perpendicular to the gradient plane and the component W x Sinθ parallel to it.

[Figure 1]

Rg = W x Sinθ

Acceleration resistance (Ri) refers to the resistance generated when the vehicle accelerates, and is formed by two types of resistance considering only the acceleration of the vehicle that does not include the resistance required for the acceleration of the rotating part and the rotating part. It is expressed as

Ri = (a ÷ g) x (W + ΔW)

Where a is the acceleration (m / sec ² ), g is the acceleration of gravity (m / sec ² ), W is the gross weight (N) of the vehicle, and ΔW is the weight (N) that corresponds to the inertia of the rotating part. The moment of inertia of the rotating part along with the engine, power train, axle, wheels, etc. is replaced by the weight of the effective radius of the drive shaft.

Normally, the engine performance can be determined from the output torque of the engine when the engine performance is expressed by the driving force of the vehicle against the driving resistance. The measurement of engine output torque is very important for engine development and performance test of actual vehicles, but currently available technology measures engine rotation speed (rpm) during engine operation and does not measure output torque.

Here, as is well known, the torque is, for example, the force to rotate the bolt when tightening the bolt with a spanner, the vertical distance from the position of holding the spanner to the center of the bolt (L), which acts to turn the bolt. If the force is F (N), the torque T (Nm) generated at this time is expressed by the following equation (6).

T = F x ℓ

When the engine is rotating, the force to turn the object is acting. This rotational force is called the shaft torque of the engine, and the relationship between the driving force and the shaft torque is expressed by the following equation.

P = (Ti i _s i _f η _m ) / r

here,

P: driving force (N)

T: Shaft torque of engine (Nm)

i _s : Gear ratio of the transmission

i _f : Gear ratio of longitudinal reduction gear

η _m : Power transmission efficiency from the engine to the drive wheels

r is the dynamic load radius (m) of the drive wheel.

There are two commonly used torque measurement methods. The most common method is to obtain the torque by dividing the output by the angular velocity by measuring the output and angular velocity separately. The other method is the clutch axle of the power train. Strain gauges attached to the surface of the probe measure the torsion of the clutch shaft and detect the signal indicating the measured torsion through the slip ring incorporated in the clutch. Applicable only when tested in and there is a problem that can not be applied when the engine is mounted on a vehicle.

In addition, recently reported technology uses a method of magnetic elasticity, but this method is also based on the measurement of the fine twist of the clutch shaft and can be applied to the real-time torque measurement while the engine is running. However, the measurement of the magnetic elasticity is a situation that there is a problem that needs to modify a portion of the clutch shaft.

The present invention has been made to solve the above-mentioned problems according to the prior art, an object of the present invention is to mount a variety of devices for measuring the engine torque in a running vehicle by running a vehicle without going through the chassis dynamometer The present invention provides a system and method for measuring engine torque.

In addition, another object of the present invention to stabilize the state of the car by inducing the continuous management of the car by easily measuring the performance of the engine for the driving vehicle, and to induce the driver safer vehicle operation.

1 is a perspective view showing a device mounting position of a measuring system in a vehicle according to the present invention;

2A to 2C are block flow diagrams showing a method for obtaining the engine torque of the present invention.

3 is a flowchart showing information input and output up to the engine torque calculation according to the present invention.

<Description of Symbols for Main Parts of Drawings>

10 speed sensor 20 engine speed measurement sensor

30 Accelerometer 40 Data Collector

60 humidity, thermometer 70 barometer

In order to achieve the above object, a feature of the present invention is to measure the engine torque of a running vehicle.

Features of the system for measuring the engine torque of a running vehicle according to the present invention is a speed sensor for measuring the running vehicle speed is installed outside the door (door) of the vehicle; A sensor for measuring the engine speed by measuring the engine; and an accelerometer for measuring the acceleration of the vehicle; and a meteorological measuring device for measuring the weather conditions of the road; and transmitted from the speed sensor, the speed sensor, and the accelerometer. And a data collecting device configured to calculate a standard value obtained by correcting the real-time weather information of the weather measuring device to a standard standby state after collecting and analyzing the received information.

In addition, the method for measuring the engine torque of a running vehicle according to the present invention comprises the steps of: mounting a measuring device in the vehicle; and obtaining a value of the free driving force; and obtaining a driving resistance value; and calculating the driving force of the vehicle running And the step of obtaining the engine torque.

Looking at the theoretical prior to explaining the present invention, it is possible to move the vehicle by the driving force (Pe) minus the total driving resistance (Rt) from the above-described driving force (P). Expressed by Equation 8, having a lot of driving force means that the acceleration force is improved. When the driving force decreases and becomes zero, the driving speed of the vehicle is indicated.

Pe = P-Rt

Rewriting Equation 8 using Equations 1 and 7 results in Equation 9 as follows.

Pe = (T i _s i _f η _m ) / r-(Rr + Ra + Rg + Ri)

In the equation (9), when driving on the flat land, Rg = 0, and if there is no free driving force, the following equation (10).

(T · i _s i _f η _m ) / r = Rr + Ra + Ri

By substituting the equations for the driving resistances into the above equations, the following equation 11 can be obtained.

(T · i _s i _f η _m ) / r = {(μ _r W) + (μ _a ㆍ V ² ) + (a ÷ g) x (W + ΔW)}

The engine torque T is obtained from Equation 11 as follows.

T = r / (i _s i _f η _m ) x {(μ _r W) + (μ _a ㆍ V ² ) + (a ÷ g) x (W + ΔW)}

By performing a vehicle test on the basis of Equation 12 and substituting the respective measured values, the engine torque in the actual vehicle state can be measured.

That is, the engine torque of the vehicle can be easily calculated based on the above theory, and each of these is analyzed and calculated through experiments on a chassis dynamometer, which is a common experimental device, and an experiment on a real vehicle driving on an actual road. Comparing the engine torque value of can be confirmed the usefulness of the present invention for the engine torque measurement in the actual vehicle state and the progress of the present invention can be confirmed.

Hereinafter, the engine torque measurement method of a running vehicle according to the present invention will be described in detail with reference to the accompanying drawings through a preferred experimental example for the method and the system as follows.

In the following description of the present invention, if it is determined that the detailed description of the related well-known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description will be avoided. Terms to be described later are terms defined in consideration of functions in the present invention, and may be changed according to intentions or customs of users or operators. Therefore, the definition should be made based on the contents throughout the specification.

In the accompanying drawings, Figure 1 is a perspective view schematically showing the mounting position of the device in the vehicle in the measurement system of the present invention, Figures 2a to 2c is a block flow diagram showing a method for obtaining the engine torque of the present invention in sequence, 3 is a block diagram of input and output of information between the apparatus and data until the engine torque of the present invention is calculated.

The vehicle used for the experiment of the present invention used the Lanos 98 year produced by Daewoo Motor, a Korean automobile manufacturer, the detailed specifications are shown in Table 1.

TABLE 1

Specification of test vehicle

Item Specifications Vehicle Maker Daewoo Model Lanos Length 4240 mm Width 1680 mm Height 1430 mm Tread Front 1405 mm Rear 1425 mm Wheel base 2,520 Curb weight 1,065 Mileage 35,000 km Engine Type E-TEC SOHC Displacement 1,498cc Max. Power 88PS / 5,600rpm Max. Torque 13.6kgfm / 3,200rpm Idle Speed 850 ± 25rpm

First, in order to check the overall performance of the test vehicle, it is generally used as a device that reproduces the same state as the actual driving of a road and is tested by using a chassis dynamometer that can comprehensively understand the performance of the vehicle. Experiment with the performance of the vehicle and check the results. The specifications of the chassis dynamometer are shown in Table 2 below.

TABLE 2

Specification of Chassis Dynamometer

Item Specifications Maker BOSCH Model FLA203 Power absorption 300kw Max. permissiable weight 3.5ton Max. roll speed 70km / h Roll size 31.8 cm

The engine vehicle is measured by calculating the load on the roller by driving the test vehicle on a roller of the chassis dynamometer. The test condition for the above test is to check the condition of the vehicle to be tested on the chassis dynamometer. At this time, the outside air condition is measured by the equipment mounted on the chassis dynamometer and used as a correction factor when calculating the engine torque with the load on the roller.

After checking the test conditions, the test method of the test vehicle in the chassis dynamometer is as follows.

Step 1 Warm up the test vehicle at 80km / h for 30 minutes.

In step 2, the gear is shifted to the second gear and then driven in an idle state.

Step 3 When the test vehicle stabilizes, accelerate by pushing the accelerator pedal to the end (WOT; Wide Open Throttle).

Step 4 When the engine speed is higher than 5,000 rpm, release the accelerator pedal and complete the test.

Repeat the test of Step 5 and Step 2 to Step 5 five times to take the average value of each data.

As described above, the engine torques measured by the engine speeds measured in the chassis dynamometer for the test vehicle are shown in Table 3 below.

TABLE 3

Engine Torque Measurement Result by Engine Speed in Chassis Dynamometer for Test Vehicle

Engine speed (rpm) Engine torque (Nm) 1200 89.3 1400 93.0 1600 97.0 1800 98.8 2000 101.2 2200 102.9 2400 106.1 2600 110.2 2800 111.2 3000 112.6 3200 112.6 3400 112.9 3600 109.4 3800 105.6 4000 102.8 4200 101.8 4400 98.7 4600 91.0 4800 81.6 5000 69.9 5200 55.7

The engine performance of the vehicle tested by the chassis dynamometer is measured value and the Korean Industrial Standard B6005-1 (reciprocating dong internal combustion engine-performance-Part 1: Standard air condition, output, fuel consumption, lubricating oil consumption and test method) It was corrected to the standard atmospheric value (atmospheric pressure 100kPa, atmospheric temperature 298 ° K, relative humidity 30%). This is to apply a reference value. The modified formula used at this time is as shown in Equation 13.

P _r = α _a x P _y

here,

P _r : Axis power under standard atmospheric conditions (kw)

α _a : correction factor

P _y : Axis power under atmospheric condition during test (kw)

The correction coefficient α _a is obtained by the following equation (14).

α _a = {(P _r -ψ _r P _sr ) / (P _y -ψ _y P _sy )} ^1.2 x (T _y / T _r ) ^0.6

here,

P _r : Standard atmospheric pressure (kPa)

P _y : Atmospheric pressure during the test (kPa)

ψ _r : saturated steam partial pressure at standard atmospheric conditions (kPa)

ψ _y : relative humidity at atmospheric conditions (%)

P _sr : Saturated water vapor partial pressure (kPa) at standard atmospheric conditions

P _sy : Saturated water vapor partial pressure (kPa) at atmospheric conditions during the test

T _y : Thermodynamic temperature of the atmosphere during the test (° K)

T _r : Thermodynamic temperature of the atmosphere under standard atmospheric conditions (° K)

Therefore, substituting the atmospheric conditions (atmospheric pressure 100.6kPa, atmospheric temperature 289 ° K, relative humidity 50%) of the test site into Equation 14 described above, the correction coefficient is α _a = 0.9741.

Equation 14 is used when the correction coefficient α _a is in the range of 0.93 to 1.07, the intake temperature at the engine inlet is in the range of T _r ± 10 ° K and the dry air pressure is in the range of 80 to 110 kPa.

In addition, the mechanical efficiency (η _m ) of the power train is calculated as 0.90, and the revised engine performance is shown in Table 4, which is shown in Figure 2.

TABLE 4

Engine performance by chassis dynamometer

[Figure 2]

Engine performance graph

Now, with reference to the accompanying Figures 1 to 3 will be described to measure the engine torque in the actual vehicle state.

In order to measure the engine torque in the actual vehicle state, the acceleration of the vehicle must be measured. In order to measure the acceleration, the vehicle speed, the engine speed, and the acceleration must be measured.

The measurement of the vehicle speed calculates the time reflected by shooting light on a road to be tested by installing a speed sensor 10 having the specifications shown in Table 5 below the door of the vehicle as shown in FIG. Measure the vehicle speed.

TABLE 5

Specification of speed sensor

Item Specifications Maker DATRON Model DLS-1 Dimensions 175 x 70 x 78 mm Weight 1.6 kg Measurement range 0.5 to 400 km / h Output signal Frequency 0 to 40 kHz Analog 0-10V Stand off distance 300 mm Environment Operation temperature -35 to + 55 ° C Storage temperature -40 ~ + 90 ℃ Relative humidity 80% at 40 ℃

The engine speed can be measured by measuring the pulse of a sensor of a gasoline engine tachometer 20 having the specifications shown in the following Table 4 by biting the wiring on the ignition coil side as shown in FIG. The engine speed of the vehicle is displayed on the engine speed measuring device.

TABLE 4

Specification of Engine Speed Measuring Device

Item Specifications Maker ONO SOKKI Model SE-152 Dimensions 180x121x144mm Weight 1.4 kg Sensor IP-292 Measurement range 500 to 10,000 rpm Power supply 12 VDC Analog Output 0-10V Operating temperature range 0 to 40 V

The acceleration is measured by installing an accelerometer 30 having the specifications shown in Table 6 in the center console of the test vehicle, and measuring the acceleration of the vehicle at the time of acceleration.

TABLE 6

Specification of accelerometer

Item Specifications Maker DATRON Model A453-0001 Dimensions 29x66x45mm Weight 140 g Measurement range ± 1 g Power supply 12 to 15 VDC Analog Output ± 5V Operating temperature range 0 to 70 V Storage temperature range -55 to 100 ℃

The data collection device 40 for importing various data is installed in a vehicle having the specifications shown in Table 7 below, and has a function of collecting, analyzing, and outputting signals measured from various sensors when the vehicle is driven.

TABLE 7

Specification of data collection device

Item Specifications Maker DATRON Model μEEP-30 Dimensions 260x230x151mm Weight 4.0kg Power supply 10 to 30 VDC Operating temperature range -15 to + 60 ° C Data memory capacity 260 MB Interface Keyboard / VGA

In addition to the above, when performing a performance test of a vehicle in a real vehicle state, weather conditions such as wind direction, wind speed, temperature, humidity, and atmospheric pressure of a test road should be measured and corrected to a standard atmospheric state. E) consists of wind and anemometer, temperature and hygrometer and barometer.

In order to measure the wind direction and the wind speed on the road of the running vehicle, there are many types of measuring instruments, but in the present invention, a wind direction and an anemometer (Wind direction and Velocity Meter) having the specifications shown in Table 8 is used.

TABLE 8

Specifications of wind direction and anemometer

Item Specifications Maker OTA Model No.24 Dimensions 70x60x1100mm Weight 1.4 kg Measurement range 0 to 22 m / s

In addition, the specifications of the humidity and temperature meter 60 for measuring the humidity and temperature of the test road and the barometer 70 for measuring the atmospheric pressure are shown in Table 9 and Table 2, respectively. Same as 10

TABLE 9

Specifications of humidity and thermometer

Item Specifications Maker VAISALA Model HM34 Dimensions 57 x 160 x 27 mm Weight 250 g Power supply 9V Battery Measurement range Humidity 0-100% RH Temperature -20 ~ 60 ℃

TABLE 10

Specifications of barometer

Item Specifications Maker ISUZU Model 3-1050-11 Dimensions 26x70x100mm Weight 135 g Power supply 12 VDC Measurement range 1050 to 790 hPa Operating temperature range -20 ~ + 70 ℃

In the above, the apparatus necessary for constructing a system for measuring engine torque in a real vehicle state has been described.

The most important thing besides the above apparatus is a test road for running performance test of a test vehicle. Normally, the driving performance test related to the powertrain is carried out on a flat surface, and the precision measurement test is performed on the well-paved asphalt bar. The place where the test of the present invention was conducted is well known to domestic automobile companies. It is a stone gate dike located in Dangjin-gun, Chungcheongnam-do, Korea. The selected test road has a total length of 9.5 km and a slight curvature at the 3.5 km point. Driving tests are generally carried out on a 6 km straight road in a two-way round trip.

Now, with reference to the accompanying Figure 2a will be described a method for measuring the driving force of the actual vehicle step by step.

First, in order to check whether the test conditions are satisfied, a step (S1) of checking the state of the test vehicle (VEHICLE) in the driving state and measuring the weight of the test vehicle and adding 136kg of payload including the driver Go through (S2). At this time, the test roads are checked and the weather conditions are checked. If snow or rain, the average wind speed is more than 5m / s or the instantaneous wind speed is more than 7m / s, the test is not performed.

After the above test conditions are satisfied, the test vehicle is equipped with the above-described measuring device (S3), and the test vehicle is warmed up by driving at a speed of 80 km / h for about 30 minutes (warm-up) (S4). After shifting to two gears, the vehicle travels in an idle state (S5). When the test vehicle stabilizes and the test vehicle is stabilized, the accelerator pedal is pressed to the end (WOT; Wide Open Throttle) and accelerated (S6). S7), when the engine speed is higher than 5,200rpm, take off the accelerator pedal and finish the test (S8), and then repeat the test of Steps 2 to 5 five times to obtain the average value of each data (S9). . Substituting the value of the acceleration for each engine speed in the standard standby state into the equation for the spare driving force (Pe) to obtain the driving force (Pe) according to the engine speed (S10).

To explain the above method in more detail, the clearance test was to accelerate acceleration in the driving state of the test vehicle and to measure the acceleration. As the vehicle speed increased, the engine speed increased and the acceleration also changed. Normally, the acceleration of a vehicle means the free driving force of the test vehicle. The decrease in speed as the acceleration value increases is because the driving resistance increases in proportion to the square of the speed.

Automatic transmission cars, unlike manual transmissions, are equipped with a torque converter that delivers power to the engine and power converter inside the transmission. It is in this state that the most power is being delivered. At this time, if you start suddenly, the acceleration of about 0.55 ~ 0.60g appears. In the case of a manual transmission car, since power is not transmitted before starting, it is necessary to accelerate rapidly while operating the clutch pedal. Therefore, the acceleration of the vehicle is lower than that of the automatic transmission vehicle, and the pitching of the vehicle may be greater due to the inability to operate the clutch.

Therefore, the test vehicle is a two-gear gear and the engine speed is idle and the engine speed is rapidly accelerated while the engine speed is 1,200 rpm. The acceleration of the place was measured and continued to 5,200 rpm. The results are shown in Table 11, and Figure 3 shows them graphically.

TABLE 11

Acceleration value for engine speed

[Figure 3]

Acceleration Value Comparison

Now, the driving force can be obtained with the acceleration value measured for each engine speed because the driving resistance can be obtained as the acceleration resistance because the driving force is used to accelerate the car. Therefore, the above formula of acceleration resistance may be used. In addition, the driving force Pe = Ri,

Pe = Ri = (a ÷ g) x (W + ΔW)

Becomes Calculating by substituting each value into the above equation,

Pe = 12.7244 x 10 ³ xa (N)

The above formula was tested under normal atmospheric conditions (atmospheric pressure 100.8kPa, atmospheric temperature 280 ° K, relative humidity 55%) and should be corrected to standard atmospheric conditions (atmospheric pressure 100kPa, atmospheric temperature 298 ° K, relative humidity 30%). .

The modified formula uses the following equation (15) used in the standby state where the above equation (14) cannot be used.

P _r = P _x / α

here,

P _r : Axis power under standard atmospheric conditions (kw)

P _x : Shaft output at ambient conditions in use (kw)

α: output adjustment coefficient

The output adjustment coefficient α is given by the following equation (16).

α = k-0.7 x (1-k) x (1 / η _m -1)

Where k is the city output ratio and η _m is the mechanical efficiency.

The city output ratio k is given by the following equation (17).

k = {(P _x -c Ψ _x P _sx ) / (P _r -c Ψ _r P _sr )} ^m x (T _r / T _x ) ⁿ x (T _cr / T _cx ) ^s

here,

P _x : Atmospheric pressure at the place of use (kPa)

P _r : Standard atmospheric pressure (kPa)

c: humidity coefficient

Ψ _x : Relative Humidity (%) at ambient conditions

Ψ _r : relative humidity (%) at standard atmospheric conditions

P _sr : Saturated water vapor partial pressure (kPa) at standard atmospheric conditions

P _sx : Partial saturated steam at atmospheric pressure (kPa)

T _r : Thermodynamic temperature of the atmosphere at standard atmospheric conditions (° K)

T _x ; Atmospheric thermodynamic temperature at the place of use (° K)

T _cr : Thermodynamic temperature of the air cooler coolant at standard atmospheric conditions (° K)

T _cx : Thermodynamic temperature of the air cooler coolant at the point of use (° K) ^s

m: Dry air partial pressure ratio or atmospheric pressure ratio index

n: thermodynamic temperature ratio index of the atmosphere

s: Thermodynamic temperature ratio index of air supply cooler coolant

By substituting the respective values into Equation 17, k can be obtained.

That is, k = {(100.8-1x0.55) / (100-1x0.94)} ¹ x (298/280) ^0.5 = 1.0440. In the case of output adjustment, if the index of expression is adjusted, c = 1, m = 1, n = 0.5, and s = 0 for a spark ignition engine (no supercharged engine) using liquid fuel.

If k = 1.0440 obtained above is substituted into Equation 16,

α = 1.0474

Will be obtained. Applying this again to the free drive formula, it becomes the free drive in the standard atmosphere. In other words,

Pe = (12.7244 x 10 ³ x α) / 1.0474 = 12.1486 x 10 ³ x α (N)

Therefore, if the acceleration value according to the engine speed is substituted here, the values for the spare driving force are obtained. This is shown in Table 12, which is shown in Figure 4.

TABLE 12

Free driving force for engine speed

[Figure 4]

Relation diagram of spare driving force according to engine speed

A method for measuring a running resistance value will now be described with reference to FIG. 2B.

First, check the condition of the vehicle to be tested in the driving state (R1), measure the weight of the test vehicle, and add 136kg of payload including the driver (R2) to check the conditions for the driving resistance test. At this time, the condition of the test road should be checked and the weather condition also checked. If it is snow or rain, it cannot be tested. The outside air temperature should be within the range of -1 ~ 32 ℃, the average wind speed should be 4.44m / s or less and the instantaneous maximum wind speed should be 5.56m / s or less, and the atmospheric pressure can be tested only at 914 ~ 1050 hPa. The slope of the road within the test section shall be at most 0.5% and the slope should be constant within ± 0.1%.

After checking whether the test conditions are satisfied as described above, close all the doors of the test vehicle (V) (R3), and maintain the constant speed for at least 3 seconds after acceleration at a speed of 8 km / h higher than the highest point of the test speed (R4). After connecting the gear neutral and the clutch, the tester will travel from 96km / h to 28km / h or less and record the test results in 3 seconds or less (R5), and stop recording (R6) below the lowest point of the test speed. Ends. After completion of the test, the gear is put in and ready for retesting (R7). In order to reduce the test error, record at least 12 times (6 round trips) from the R3 step to the R7 step in the same test section and record them in sequence, and record the average outside condition at each test (R8).

It is better not to change lanes during the above test. If it is unavoidable, change lanes slowly at a distance of more than 500m and stop the test and retest when changing lanes.

After inputting and executing the result of the running resistance test using the other performance analysis program registered in "SAE Paper J1263" (R9), the running resistance value Rr calculated by the engine speed calculated through the program is calculated (R10). ).

In the above description, the performance calculation program of "SAE Paper J1263" uses the following calculation formulas.

① vehicle frontal area of the test vehicle

If the front area of the test vehicle is known, the actual value shall be used. Otherwise, the following equation shall be used.

A = 0.8 x (H101) x (W103)

here,

A: Front projection area of the test vehicle (㎡)

H101: Height of test vehicle (m)

W103: Overall width of the test vehicle (m)

② Vehicle weight

It includes the tolerance weight of the test vehicle and the load capacity of 136 kg.

Test vehicle weight = Vehicle curb weight + Payload (kgf)

③ Actual vehicle weight

If the exact value is not known as the sum of the weight of the test vehicle and the weight of inertia of the equivalent parts of rotation, the value is taken as

Me = 1.03 x M (kgf)

here,

Me: Effective vehicle weight

M: Test vehicle weight

④ drive line component inertia weight

If the exact value is not known as the inertia weight of the equivalent part of rotation to the drive shaft of the test vehicle, the value calculated by the following formula is taken.

MDLC = 0.015 x M (kgf)

Where MDLC: Drive line component inertia weight

⑤ Dynamometer inertia weight of chassis dynamometer

As the inertial weight of the chassis dynamometer corresponding to the weight of the test vehicle, the equivalent inertia weight corresponding to the test vehicle weight is taken from the equivalent inertial weight table in Table 13 below.

TABLE 13

Equivalent Inertia Weight Table

Car weight Equivalent Inertia Weight kg lb kg lb 992.2-1048.8 2188-2312 1020.6 2250 1048.9 to 1105.5 2313-2437 1077.3 2375 1105.6 ~ 1162.2 2438-2562 1134.0 2500 1162.3-1218.9 2563-2687 1190.7 2625 1219.0 to 1275.6 2688 ~ 2812 1247.4 2750 1275.7 to 1332.3 2813 ~ 2937 1304.1 2875 1332.4 to 1389.0 2938-3062 1360.8 3000 1389.1 ~ 1445.7 3063-3187 1417.5 3125 1445.8 to 1502.4 3188 ~ 3312 1474.2 3250 1502.5 ~ 1559.1 3313 ~ 3437 1530.9 3375

In the actual vehicle test, the other vehicle is tested 16 times by the test vehicle, and the running resistance is calculated from the 12 test results. In order to obtain the running resistance, the data shown in Table 15 is outputted when the data of the following Table 14 is input to the performance analysis program registered in SAE Paper J1263.

TABLE 14

Input data of other performance analysis program

TABLE 15

Execution result output data of other performance analysis program

The driving resistance received by the test vehicle in the actual vehicle state is expressed by the rolling resistance and the air resistance as the following equation (18),

F = F ₀ + F ₂ x V ²

here,

F: Running resistance (N)

F ₀ : rolling resistance (N), same as μ _r x W

F ₂ : Sum of air resistance coefficient and front projection area (kg / m)

V: Speed of car (km / h)

As a result of substituting the corresponding values into Equation 18,

F ₀ = 33.4 (lb) x 0.4536 (kgf / lb) = 15.15 (kgf)

F ₂ = 0.0218 (lb / ft) x 0.4536 (kg / lb) x 1 / 0.3048 (ft / m)

x (1 (h ² ) x 1000 ² x 1 (m ² )) / (1 (km ² ) x 3600 ² x 1 (s ² ))

= 2.4996 x 10 ^-3 (N · h ² / km ² )

To express the running resistance for each engine speed, the following equation 19 is used.

V = (nx 2 x πx rx 60) / (i _s xi _f x 1000)

here,

V: Vehicle speed (km / h)

r: Dynamic load radius of the tire (= 0.278m)

i _s : Gear ratio of the transmission (= 2.048)

i _f : Gear ratio of longitudinal reduction gear (= 4.176)

By substituting the engine speed in Equation 19, the vehicle speed and the driving resistance can be obtained as shown in Table 16.

TABLE 16

As a result of running resistance

This is shown graphically in Figure 5.

[Figure 5]

Running resistance graph

When the driving force P is obtained from the allowable driving force Pe and the total driving resistance Rt obtained through the actual vehicle test, the driving force is given by Pe = P-Rt of Equation 8

P = Pe + Rt

Becomes

Therefore, when the driving force in accordance with the engine speed and the total running resistance are added, the driving force in the actual vehicle state is shown in Table 17, which is shown in Figure 6.

TABLE 17

Free driving force for engine speed

[Figure 6]

Relationship between engine speed and clearance

The engine torque T in the actual vehicle state is obtained by the driving force P obtained through the actual vehicle test as described above. In this case, using the equation (7) to obtain the driving force (P),

P = (Ti i _s i _f η _m ) / r

Engine torque T is

T = (P xr) / (i _s ㆍ i _f ㆍ η _m )

Where r = 0.278 (m), i _s = 2.048, i _f = 4.176, and η _m = 0.90,

T = 0.0361 x P (Nm)

Becomes

Therefore, the engine torque in the actual vehicle state can be obtained by substituting the driving force value according to the engine speed. This value is shown in Table 18.

TABLE 18

Engine performance by driving

[Figure 7]

Engine performance by driving

As described above, the engine torque measured by the chassis dynamometer and the engine torque measured in the driving state are shown in Table 19, and Fig. 8 shows this as a graph.

TABLE 19

Comparison between engine performance

[Figure 8]

Comparison between engine performance

Compared to the engine torque measured by the chassis dynamometer as described above, the engine torque measured in driving condition was 1.69% lower in all the ranges, and showed a slight difference by the engine speed. Figure 9 illustrates this relationship.

[Figure 9]

Graph showing difference in engine performance

As described above, the measured values of the engine torque of the chassis dynamometer and the running vehicle are slightly different from each other, but this is an error within the range of use, so there is no problem in its utilization.

It is a very useful invention having the effect of measuring the engine torque of a running vehicle without passing through the chassis dynamometer through the engine torque measuring system and method of the running vehicle of the present invention.

Another effect of the present invention is to easily measure the engine performance of the driving vehicle to induce the continuous management of the car to stabilize the state of the car and induce the driver to drive the vehicle safer.

Claims (7)

In measuring engine torque of a running vehicle, Is installed outside the door of the vehicle speed sensor 10 for measuring the running vehicle speed; And Engine speed measurement sensor 20 for measuring the rotational speed of the engine by measuring the pulse (pulse) by biting the wiring of the ignition coil side of the vehicle engine; and Accelerometer 30 is mounted on the vehicle for measuring the acceleration; And A meteorological measuring device (E) installed on the outside of the vehicle and for measuring weather conditions of a road on which a running vehicle runs; and A data collecting device 40 for collecting and analyzing information transmitted from the speed sensor, the rotation speed measuring sensor, and the accelerometer, and then calculating a standard value corrected in real time weather information received from the weather measuring device to a standard standby state; The engine torque measurement system of a real running vehicle, characterized in that it comprises a; characterized in that to output the information processing data for calculating the engine torque of the actual vehicle. The method according to claim 1, The meteorological measuring device (E) Wind direction and anemometer 50 for measuring the wind direction and wind speed of the road; and Humidity and thermometer 60 for measuring the humidity and temperature of the road; and A barometer 70 for measuring the atmospheric pressure of the roadway; Engine torque measurement system of a running vehicle, characterized in that consisting of. In the method for measuring the engine torque of a running vehicle, Mounting a speed sensor, an engine speed sensor, an accelerometer, and a data collection device to a vehicle; and Calculating a standard value obtained by correcting the information of the data collecting device and the real-time weather information received from the weather measuring device to a standard standby state; and Obtaining a spare driving force value Pe of the vehicle; and Obtaining a running resistance value Rr of the vehicle; and Calculating a driving force P of the vehicle by using the marginal driving force value Pe and the driving resistance value Rr; And Obtaining engine torque (T) of a vehicle by substituting the driving force (P) for an engine torque formula; Engine torque measurement method of the vehicle running, characterized in that consisting of. The method of claim 3, wherein The marginal driving force value Pe Checking the state of the vehicle in the driving state to check whether the test condition is satisfied (S1); and Measuring the weight of the vehicle (V) and adding a payload (136 kg) including a driver (S2); and Mounting the aforementioned measuring device on the test vehicle (S3); and Warming up the test vehicle at a speed of 80 km / h for about 30 minutes (S4); and Shifting the gear stage to the second stage and driving in an idle state (S5); When the test vehicle is stabilized by stepping on the accelerator pedal to the end (WOT; Wide Open Throttle) to accelerate (S6); Measuring the acceleration of the place where the engine speed is increased by 200 rpm in increments of 200 rpm according to the acceleration up to 5,200 rpm (S7); and When the engine speed is higher than 5,200rpm step (S8) to step off the accelerator pedal and end the test; and Performing a test from Step S4 to Step S8 five times to obtain an average value of each data (S9); And, Obtaining an allowable driving force Pe according to the engine speed by substituting the equation for the allowable driving force Pe corrected to the standard atmospheric condition by the acceleration value for each engine speed (S10); Method for measuring the engine torque of a vehicle during driving, characterized in that the composition is obtained. The method of claim 3, wherein The running resistance value Rr is Checking the state of the vehicle in a running state (R1); and Measuring the weight of the vehicle and adding 136 kg of payload including the driver (R2); and Closing all doors of the vehicle (R3); and Maintaining a constant speed for at least 3 seconds after the acceleration at a speed of 8km / h higher than the highest point of the test speed (R4); After the gear neutral and the clutch connection, the test results are recorded in a unit of 3 seconds or less at a speed of 96 km / h or more and 28 km / h or less (R5); Terminating the test by stopping recording at or below the lowest point of the test speed (R6); and After the end of the test to put the gears and preparing for retest (R7); and, At least 12 tests from the step R3 to the step R7 in the same test interval to record in order, but recording the external state at each test to obtain the average value (R8); And, Inputting and executing the running resistance value by using the other performance analysis program registered in "SAE Paper J1263" (R9); And Obtaining a running resistance value Rr for each engine speed calculated and executed through the program (R10); Method for measuring the engine torque of a vehicle during driving, characterized in that the composition is obtained. The method of claim 3, wherein Equation for the engine torque (T) is T = 0.0361 x P (Nm) An engine torque measuring method of a vehicle while running. The method according to claim 4, Equation for the spare driving force (Pe) corrected to the standard standby state Pe = 12.1486 x 10 ³ x α (N) An engine torque measuring method of a vehicle while running.