JPH05346373A - Operating method of equipment for collision experiment of vehicle - Google Patents

Abstract

PURPOSE:To improve sharply the precision of a separation speed on the basis of two detection points without using a complicated arithmetic device, by selecting or modifying an optimum curve of transfer to a fixed speed on the basis of a taken-up length of a tractive rope between the two detection points. CONSTITUTION:The weight of a vehicle C to be tested is set and acceleration is made along a rise curve SL and at a prescribed rate. At this time, speeds and running resistance values at the time when the vehicle C passes a point tp1 near a starting point, at which the speed of the vehicle C is very low, and a point tp2 in a relatively low speed region in which the acceleration is made at a prescribed acceleration are detected, the constant of a running resistance function in storage is modified thereby and the running resistance function of a whole system is set. Thereby the running resistance value at a target speed, i.e., a driving force of a drive motor, in other words, the amount of elongation of a tractive rope, can be estimated. By measuring the amount of elongation of the rope at the time of the maximum acceleration caused by a prescribed driving force from the amount of the rope taken up during the time required for passing between the two points, on the other hand, the amount of contraction of the rope after the target speed is reached can be estimated, and an optimum curve of decrease of acceleration to the target speed can be selected on the basis of the aforesaid amount of contraction and the amount of inertia which is the load of the rope.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention drives a take-up drum of a towing rope by a drive motor to accelerate the vehicle under test by towing the towing rope, and when a predetermined speed is reached. The present invention relates to a driving method of a collision test device for a vehicle, in which a vehicle under test is disconnected from a tow rope and the vehicle under test collides with an object by coasting.

[0002]

2. Description of the Related Art In this type of driving method, the applicant of the present invention has shown that, as shown in FIG. 2, a vehicle or a towing trolley (drive truck) is provided at three points (tp1, tp2, tp3) on the acceleration road of the vehicle under test. 3) Passing detectors for moving objects C such as Lee) are provided, and the driving force of the drive motor at the time of passing each of these detection points is detected or calculated, and at the same time between each detection point (tp1
And tp2, and between tp2 and tp3), the take-up length of the tow rope is measured by the take-up drum, and the running resistance value and the tow lobe of the entire system at the target speed are measured. We first proposed a method of operating a vehicle collision test system, which is characterized by estimating the damping vibration phenomenon of the vehicle, obtaining the optimum acceleration curve, and then operating the drive motor according to this acceleration curve. By the way, the summary of the above proposal is as follows.

That is, in this type of driving method, a heavy vehicle to be tested has to be accelerated to a predetermined high speed in a traveling path of a limited length, so that the acceleration is considerably large. Therefore, the traction rope is greatly stretched during acceleration. Then, the speed of the vehicle under test approaches a predetermined target speed, and when the acceleration is gradually reduced in order to properly match the speed, the traction rope stretched because the driving force of the drive motor is reduced contracts, Tow lo
The elasticity of the pump and the inertia of the vehicle under test interact with each other,
Vibration is generated in the direction in which the length of the tow rope changes.

Therefore, no matter how the speed of the take-up drum is correctly adjusted to the target speed, the speed of the vehicle under test is not stable immediately because the towing rope is expanding and contracting.
There is a problem that it is very difficult to match the speed of the vehicle under test to the target value within a short time limited by the length of the traveling path.

In order to solve this problem, in the above proposal, the following equation 4 between the running resistance F of a moving object and its speed v, which is well known in the world, is established. Pay attention to three points on the acceleration road,
Three or more passage detectors for moving objects such as Lees are provided, and the driving force F of the drive motor at the time when each passage detector detects the passage of a moving object is obtained by measurement or calculation, and v for each of them is calculated. The running resistance function of the entire system is calculated from the values of F and F.

[0006]

[Equation 4]

Further, the winding length of the pulling rope by the winding drum between the detection points is measured, and the pulling rope is compared by comparing this length with the actual distance between the detection points. Is seeking the amount of growth.

On the other hand, the spring constant and damping constant of the traction rope can be set before the experiment.
The damping vibration phenomenon of the traction rope is estimated from these data, and the optimum acceleration diminishing curve for minimizing the vibration of the traction rope is obtained.After that, the drive motor is operated according to this curve. When the speed of the winding drum reaches the target speed, the speed of the vehicle under test is simultaneously adjusted to the target speed.

[Problems to be Solved by the Present Invention]

An object of the above invention is to perform a vehicle collision experiment in which the vehicle under test can be immediately separated at a predetermined speed at a target speed without performing a test run in advance, and can be made to collide with an object at a desired highly accurate collision speed. To get the operating method of the device.

To this end, a plurality of passage detectors for the moving object C such as the vehicle or dolly are provided at at least three points (tp1, tp2, tp3) on the acceleration running path of the vehicle under test, and the passage detection is performed at the time when the passage is detected. By solving simultaneous quadratic equations from the respective values of v and F, the running resistance function of the entire system is obtained, and at the same time, the extension amount of the traction rope is obtained.

Then, the damping vibration phenomenon of the traction rope is estimated from these data, an optimum acceleration gradual curve for minimizing the vibration of the traction rope is obtained, and the acceleration by the constant driving force is obtained. The drive motor is operated in accordance with this gradual decrease curve when shifting from the target speed to the target constant speed.

[0012] However, according to the verification by the inventor of the present applicant by the actual machine, the rope-pulling type collision experiment device using the above method has achieved great results, and the rope-pulling type collision experiment before that has been achieved. In the device, even if the weight of the vehicle under test is limited to a considerably narrow range, the speed error is ± 1.0 to 1.5 Km / h and 120 Km / h at the target speed of 100 Km / h.
In terms of h, about ± 2 km / h was the common sense level of the general public, but for a wide range of vehicles from 1 ton to 20 tons, ± 0.5 km at speeds up to 140 km / h. The separation speed accuracy of less than / h was greatly improved.

However, in the above example, the towed vehicle was used immediately before being discarded and was manufactured under the bad condition that the running resistance value could not be estimated. Since it is manufactured, the accuracy of vehicle separation speed is high over a wide range of gravity and speed, while it is a relatively expensive device.

Therefore, the inventor of the present applicant proposes the above-mentioned proposal in consideration of the case where the vehicle under test is a new vehicle or a vehicle in normal use and the running resistance function does not change so much if the vehicle types are the same. In the invention of claim 3, the number of passage detectors required to be three or more is set to two, and a complicated arithmetic device is not used. Therefore, a collision experiment device which is more economical and can exhibit the performance close to the above-mentioned example is provided. It is intended to provide a driving method.

[0015]

The method for operating the vehicle collision test apparatus according to the present invention is such that the winding drum of the tow rope is driven by the drive motor and the vehicle under test reaches a predetermined speed. In the driving method of the collision test device for a vehicle in which the joint with the tow rope is cut off and the vehicle under test collides against the object by coasting, the point where the speed of the vehicle under test is extremely low near the starting point of the vehicle under test. Acceleration road of tp1 and point t of relatively low speed range
A moving object passage detector is provided on the acceleration traveling path of p2, and the driving force of the drive motor at the time of passing these detection points tp1 and tp2 is detected or calculated, and the pulling rope by the winding drum between the detection points is obtained. For the purpose of measuring the take-up length of the machine and using the constant speed transfer curve stored in advance to minimize the vibration of the tow rope and transfer to the target speed in a short time. It is characterized in that the optimum one is selected and corrected, and the drive motor is operated according to the modified curve at the time of shifting to the constant speed.

[0016]

The present invention will be described in detail below with reference to the embodiment shown in FIG.

First, in the method of estimating the running resistance value of the entire system at the target speed in the prior application, three points at which the extension of the traction rope (in other words, the traction force) hardly changes are selected,
In this method, a running resistance function is obtained by solving simultaneous quadratic equations from v and F at these points, and the target speed value is substituted into this to find the running resistance value at the target speed.

Therefore, since three sets of values of v and F are theoretically required, three moving object passage detectors must be provided, and simultaneous simultaneous quadratic equations can be calculated within a limited time. I had no choice but to do the complicated task of solving it.

On the other hand, in the present application, when considering the above-mentioned equation (4) of the running resistance function of the entire system, an average running resistance function of the entire system is stored in advance for each vehicle type. ..

[0020]

[Equation 4]

Of the values of A, B, and C, the value of B (Bc) for the vehicle is originally small, and the running resistance of the mechanical system other than the vehicle hardly depends on the vehicle type of the vehicle under test. Since the respective constants Am, Bm, and Cm are considered to be almost invariable, B (= Bm + Bc) is not changed and only A and C are modified to be regarded as the running resistance function of the entire system. It doesn't come off too much. This is because there is an idea that the running resistance function of the vehicle is regarded as the following Equation 5.

[0022]

[Equation 5]

Therefore, the moving object passage detector is placed at a point tp near the starting point of the vehicle under test where the speed of the vehicle under test is extremely low.
1 and two points on the acceleration traveling path of a point tp2 at which the vehicle is accelerated in a relatively low speed range and with a constant driving force, and the values of v and F when the moving object C passes through these two points , After correcting only A and C of the stored constants of the running resistance function,
It can be regarded as a running resistance function of the entire system.

Thus, if the running resistance function of the entire system is determined, the running resistance value at the target speed, that is, the driving force of the drive motor can be estimated, in other words, the extension amount of the traction rope at that time can be estimated. become.

And, on the one hand, the above-mentioned tp1 and t
Since the amount of expansion of the rope at the maximum acceleration by a constant driving force is measured from the amount of winding of the winding drum's towing rope while passing through p2, the towing rope after these target speeds is measured. It is possible to estimate the amount of contraction of the rope, and from this value and the amount of inertia that is the load of the traction rope, it is possible to select the optimum acceleration diminishing curve to the target speed.

Hereinafter, the case where the drive motor is a DC shunt winding motor, which is generally used as a large-scale collision experiment device, will be taken up, and its operation method will be described in the order of actual experiments.

First, the weight of the vehicle under test C is set,
As a result, acceleration is started with a preset rising curve (current value rising curve) SL and constant acceleration. At this time, a point at which the speed and current value of the vehicle under test at or near the starting point are extremely low (tp1 point), and a point in a relatively low speed region where the rising curve SL ends and acceleration is performed at a constant current value ( A total of two passage detectors for the moving object C such as a vehicle or a tow truck (dolly) are provided at tp2 point). Then, at the points tp1 and tp2, the speed of the winding drum at the time when the passage of the vehicle under test is detected is v1,
If v2 and the driving force of the drive motor obtained by the measurement or calculation at that time are F1 and F2, the following formula 1 (two formulas) is established.

[0028]

[Equation 1]

At point tp1, the vehicle under test C is tested.
Since the speed of is close to “0”, the approximate value of this F1 (the number is a half-width) can be considered as A. Next, by taking the difference between the two expressions of the above expression 1, the following expression 2 is derived.

[0030]

[Equation 2]

Also here, as described above, if the fact that v1 (numbers are half-width) can be regarded as "0" in comparison with v2 (numbers are half-width), the above equation 2 is used. Can be regarded as Equation 3 as follows.

[0032]

[Equation 3]

Since the value of Bm (B for mechanical device), which occupies most of B, is invariable with respect to the type of vehicle, B (= Bm + B) including the amount of the vehicle under test in advance is also included.
If the value of c) is stored, the approximate value of C can be obtained by a very simple calculation.

Since the values of A and C can be approximately obtained by the above-mentioned simple operation, the running resistance function of the entire system can be defined by the above-mentioned formula 4.

On the other hand, in the winding drum, the winding length of the traction rope is measured. The speed detection signal can be used for this purpose, and the winding length of the tow rope can be easily measured by counting the number of pulses of the speed detection pulse oscillator, for example.

The running resistance function of the entire system is estimated by the above method, and the running resistance value of the entire system at the time of the target speed, in other words, the traction force required by the drive motor at that time, that is, the traction force proportional to this value, is obtained. The length of the tow rope can be estimated.

On the other hand, by measuring the winding length of the tow rope while the vehicle under test C travels between points tp1 and tp2, and comparing it with the actual distance during this period, acceleration is achieved with the maximum driving force. You can know the amount of extension of the tow rope inside. Then, the contraction length of the traction rope when the target speed of the vehicle under test is matched can be predicted from both values.

Therefore, in consideration of the expected contraction length of the traction rope and the inertial amount of the vehicle under test that is the load of the traction rope, the constant speed transition curve stored in advance is selected. It is possible to select and correct the optimum one for the purpose of minimizing the vibration of the tow rope and shifting to the target speed in a short time.

[0039]

As is apparent from the above description, the conventional operation method requires three moving object passage detectors, but the present invention requires two detectors. it can.
Therefore, the equipment can be simplified.

At the same time, the calculation for determining the running resistance is simplified, and the optimum constant is selected from those stored in advance for the constant speed transition curve and is corrected, so that the running resistance is determined and thereafter. The gradual decrease of acceleration curve can be determined in a short time using a simple arithmetic device.

Therefore, according to the present invention, the economical efficiency of the equipment as a whole is high.

[Brief description of drawings]

FIG. 1 shows “time (horizontal axis X)” of a vehicle under test according to the present invention.
~ Speed (vertical axis Y) "curve.

FIG. 2 is a “time (horizontal axis X) to speed (vertical axis Y)” curve of a vehicle under test in a conventional example.

[Explanation of symbols]

Vc ... Vehicle speed under test, Vm ... Drive motor speed, tp1, tp2 ... Time of detection of passage of vehicle under test by each passage detector, tc ... Time of disconnection of tow rope and vehicle under test

Claims (1)

[Claims] 1. A winding drum of a tow rope is driven by a drive motor, and when the vehicle under test reaches a predetermined speed, the connection with the tow rope is cut off and the vehicle under test is subjected to coasting. In the driving method of the collision experiment device of the vehicle that collides with an object,
Passing detectors for moving objects are respectively provided on the acceleration running path at a point tp1 where the speed of the vehicle under test is extremely low near the starting point of the vehicle under test and the acceleration running path at a point tp2 in a relatively low speed range. The driving force of the drive motor when passing through the detection points tp1 and tp2 is detected or calculated, and the winding length of the pulling rope by the winding drum between the detection points tp1 and tp2 is measured. From the stored constant speed transfer curve, select the optimum one for the purpose of minimizing the vibration of the tow rope and moving to the target speed in a short time, and modify it. ,
A method for operating a vehicle collision experiment device, characterized in that the drive motor is operated in accordance with the modified curve at the time of shifting to a constant speed.