JPH0665977B2 - Automatic speed control method in vehicle mode test - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an automatic speed control method, particularly a double roller chassis dynamo, in a vehicle mode test for an exhaust gas test or the like. The present invention relates to what is utilized to perform appropriate vehicle speed feedback control even during acceleration and deceleration.

[Prior Art] When running a vehicle on a double-roller chassis dynamo with an automatic driving device and conducting a test (mode test) of exhaust gas and fuel consumption under various operating conditions, a tacho generator connected to an idle roller and pulse generation The speed is detected by the detector, and the detected value is fed back to control the speed of the vehicle.

[Problems to be Solved by the Invention] The following problems have been encountered in such a mode test by the conventional automatic driving device.

Disturbance of the speed signal occurs due to the longitudinal movement of the vehicle that occurs during acceleration, deceleration, and gear shift, and accurate speed automatic control cannot be performed due to the disturbance of the speed signal.

Due to such drawbacks, in the mode test, the driver rides on the vehicle, predicts the next mode while comparing the speed detected by the idle roller with a predetermined driving schedule, and The problem was solved.

The test data varies due to individual differences among drivers.

The present invention has been made to solve these problems, and provides an automatic speed control method in a vehicle mode test capable of performing appropriate speed control even during gear shifting, acceleration, and deceleration. To aim.

[Related Art] Japanese Patent Laid-Open No. 60-253839 and Japanese Patent Laid-Open No. 61-734 disclose a technique of dividing one target value into two depending on whether acceleration or deceleration is performed.

[Means for Solving the Problems] In the mode test of the vehicle performed by running the vehicle on a double-roller chassis dynamo having two rollers, a drive roller and an idle roller, the present invention sets the wheels of the vehicle to the above-mentioned two. The rollers are rotated in contact with each other, the rotation speeds are detected by speed detection sensors respectively connected to the rollers, and these two detection values are input to the multipliers and set for the purpose of the mode test. Acceleration is calculated by calculating the speed set value, weights for multiplying the detection values of the two rollers by this acceleration are calculated, and these weights are input to the respective multipliers, where the above two detection values are multiplied. Then, the two obtained calculation results are added together to calculate a weighted average speed value, and the vehicle speed is calculated based on the calculated speed value. It is characterized by feedback control.

[Operation] When carrying out the mode test of the vehicle based on such a method, it operates as follows.

The vehicle is moved so that its wheels are located on the two rollers of the double chassis dynamo, the drive roller and the idle roller. Then, the wheel is rotated on the two rollers. Then, the rotation speeds of the two rollers are detected by speed detection sensors provided in the rollers. Then, these two detected values are respectively input to the multipliers. On the other hand, the acceleration is calculated by calculating the speed set value set for the purpose of the mode test.
Since this acceleration has a fixed relationship with the two speed detection values of the drive roller and the idle roller, a weight to be multiplied by the two speed detection values is calculated from this acceleration. Each of these weights is input to the multiplier, where 2
It is multiplied by two speed detection values. The two calculated results thus obtained are added together to calculate a weighted average speed value, and the speed of the vehicle is feedback-controlled by this speed value.

In this way, two of idle roller and drive roller
The speed detection values of the two rollers are not fed back as they are, but they are fed back after weighted averaging.
Appropriate speed values are obtained even during acceleration and deceleration, and speed control is performed using this, which enables automatic operation in the mode test.

[Embodiment] An automatic speed control method in a vehicle mode test according to the present invention will be described with reference to the drawings.

FIG. 1 is an overall block diagram showing an embodiment of the control method of the present invention.

The vehicle 10 has its drive wheels 12 (rear wheels in this case) located above the double-chassis dynamo 14. The drive wheel 12 is positioned in contact with both the idle roller 16 provided on the rear side and the drive roller 18 provided on the front side. Here, when the vehicle 10 travels, that is, the drive wheels 12 rotate, the idle roller 16 and the drive roller 18 also rotate. The idle roller is a roller that rotates without applying a load, and the drive roller is a roller that applies a load to wheels and rotates. The idle roller 16 is connected to a speed detection sensor 20 that generates a pulse according to this rotation.
Then, the speed detection value obtained here is converted into the DC voltage signal a by the frequency-voltage converter (F / V) 22 and then input to the multiplier 22. The drive roller 18 is connected to the multiplier 30 via the speed detection sensor 26 and the frequency-voltage converter 28. Then, as in the case described above, it is converted into a DC voltage signal b corresponding to the rotation of the drive roller 18 and input to the multiplier 30. On the other hand, the speed setting value, which is the speed setting value for performing the mode test, is the acceleration calculator.
Entered in 32. Then, here, the predicted acceleration value k is calculated from the speed setting value. Generally, the acceleration predicted value k is calculated by differentiating the speed setting value. further,
The acceleration calculator 32 stores a weight value to be multiplied by the speed detection values (DC voltage signals a, b) obtained from the idle roller 16 and the drive roller 18 according to the predicted acceleration value k. This weight is obtained by actually running the vehicle on the double roller chassis dynamo and measuring the relationship between the speed detection value and the acceleration predicted value k obtained from the two rollers at that time. The relationship between the weight and the speed value is stored as a feedback distribution curve for each vehicle type, the predicted acceleration value k is applied to this feedback distribution curve, and the weights c and d are output. For example, the weights c and d are calculated as follows. First,
The control coefficient F (k) is obtained from the predicted acceleration value k. That is, when the predicted acceleration value k is 0.1 G, the control coefficient F
When (k) is 0.7 and the predicted acceleration value k is -0.1G, the control coefficient F (k) is 0.6, and when running at constant speed (the predicted acceleration value k is 0), the control coefficient F (k) is 0.2. A feedback distribution curve that outputs such a value is stored. The weights c and d are calculated by distributing the control coefficient F (k) to the weight c for the idle roller 16 and the weight d for the drive roller 18 as follows.

c = F (k) d = 1-C = 1-F (k) Here, the control coefficient is set to a number between 0 and 1.

The weights c and d thus obtained are input to the multipliers 24 and 30, respectively, where they are multiplied by the DC voltage signals a and b corresponding to the respective speed detection values, and the control signals e and f are output. It That is, the following control signals e and f are obtained.

e = c · a f = d · b = (1-c) b Then, the control signals e output from the multipliers 24 and 30 are
f is added and the corrected speed signal g is obtained.

g = e + f = c · a + (1-c) b The corrected speed signal g thus obtained is the weighted average without changing the absolute values of the DC voltage signals a and b which are signals corresponding to the speed detection value. It has been made.

The corrected speed signal g is input to the control amplifier 34 and used as a signal for feedback. And this control amplifier
A speed setting value is also input to 34, and the result of these comparisons is output as an operation signal. With this operation signal, the actuator 36 mounted on the vehicle 8 is operated,
The wheels 12 are controlled to rotate at the set speed. The actuator 36 is usually provided with two throttle actuators that adjust the opening of the throttle and a brake actuator that adjusts the brake, and the rotation speed of the wheels is controlled by this.

During acceleration and deceleration, drive roller 18 and wheels 12
There may be a case where a slip occurs between them, and the correct rotational speed of the wheel, that is, the traveling speed of the vehicle cannot be obtained from the rotational speed of the drive roller 18. Therefore, the weight of the speed detection value on the idle roller 16 side is increased. Further, since the above-mentioned slip hardly occurs during traveling at a constant speed, the weight of the speed detection value on the drive roller 16 side is increased. In this way, the error in speed detection is removed,
Stable control can be performed. Therefore, the speed of the vehicle can be controlled according to the speed set value command, and a desired mode test can be performed.

When tacho generators are used as the speed detection sensors 16 and 18, the frequency-voltage converters 22 and 28 are unnecessary.

[Effects] As described above, according to the automatic speed control method in the vehicle mode test of the present invention, the following effects can be obtained.

It is possible to perform a mode test of exhaust gas, fuel consumption, etc. by unmanned automatic operation on a double chassis dynamos, which was difficult in the past.

Variations in test data due to individual differences among drivers are eliminated, and stable tests can be performed.

It is possible to follow the command vehicle speed with the minimum accelerator work, and it is possible to perform a test close to that when a human is driving.

[Brief description of drawings]

FIG. 1 is a block diagram showing the circuit of an embodiment according to the method of the present invention. 10 …… Vehicle 12 …… Wheels 14 …… Double roller chassis Dynamo 16 …… Idle roller 18 …… Drive roller 22,28 …… Frequency-voltage converter 24,30 …… Multiplier 32 …… Acceleration calculator 34… ... Control amplifier

Claims (2)

[Claims] 1. In a mode test of a vehicle performed by running the vehicle on a double roller chassis dynamo having two rollers, a drive roller and an idle roller, the wheels of the vehicle are rotated in contact with each other on the two rollers. The rotation speed is detected by the speed detection sensor connected to each of the rollers, the two detection values are input to the multipliers, and the speed set value set for the purpose of the mode test is calculated to calculate the acceleration. Is calculated, and the weight by which the detection values of the two rollers are multiplied by this acceleration is calculated, and this weight is input to each of the multipliers, where
One detection value is multiplied, the two obtained calculation results are added together to calculate a weighted average speed value, and the speed of the vehicle is feedback-controlled by the calculated speed value. Automatic speed control method in mode test. 2. An automatic vehicle mode test according to claim 1, wherein a weight value obtained from said drive roller and multiplied by a detected value is increased when said acceleration value is large. Speed control method.