Vehicle Crash Test Equipment

Abstract

To solve the problem that the vehicle speed deviates from a predetermined speed at a separation position of a vehicle by feeding back the traction speed at the position where the influence of expansion and contraction of a traction rope is minimized.SOLUTION: A vehicle collision test device includes: a traction rope 1; a drum 2 for pulling the traction rope 1; a plurality of sheaves 3 (3A, 3B) engaged with the traction rope 1; a motor 4 for driving the drum 2; and control means 5 for controlling the motor 4 based on a traction speed command Vref. In a collision test in which a vehicle 7 is connected to a connection point C set on the traction rope 1 via a dolly 6, which is connection / disconnection switching means, a sheave speed detection part 31 is installed on the sheave 3B at a position closest to the connection point C of the vehicle, and the sheave speed Vs detected by the sheave speed detection part 31 is inputted to the control means 5 to control the motor 4.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a vehicle crash test device that can minimize the effects of expansion and contraction of a tow rope during a vehicle crash test. [Background technology]

[0002] Conventionally, automobile manufacturers have conducted crash tests in which vehicles are actually collided with each other to evaluate the strength of the vehicle body and the effects of the collision, assuming a vehicle collision accident. An example of this type of vehicle crash test device is shown in Patent Document 1.

[0003] FIG. 5 shows a configuration that belongs to the closed-loop system described in the document.

[0004] This vehicle collision test device includes a towing rope 101, a drum 102 that tows this towing rope 101, a plurality of sheaves 103 that engage with the towing rope 101, a motor 104 that drives the drum 102, motor speed detection means 104a that detects the speed of the motor 104, and control means 105 that converts the detected motor speed into an actual towing speed in a conversion section 105a, feeds it back, and inputs a torque command Tr to the motor 104 through a PI control section 152 based on the deviation from the towing speed command Vref.

[0005] The vehicle 107 is connected to the towing rope 101 via a connection / disconnection switching means 106, and after the vehicle 107 is run on a running path 108, it is disconnected by the connection / disconnection switching means 106 and crashed into an object 109 at a predetermined speed, thereby conducting a test.

[0006] 6 shows a velocity diagram and an acceleration diagram that are the execution reference when the control means 105 issues the traction speed command Vref. The acceleration is set so as to be completed within the basic acceleration time A. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 7-35651 DISCLOSURE OF THE INVENTION [Problem to be solved by the invention]

[0008] However, since the vehicle 107 must be accelerated to a predetermined high speed within the limited length of the running path 108, the acceleration is large, and the towing rope 101 has a spring constant, so it is stretched greatly during acceleration and then contracts before the acceleration ends.

[0009] This expansion and contraction of the towing rope 101 causes a deviation between the speed of the vehicle 107 and the speed of the motor 104. For this reason, in response to the towing speed command shown in Fig. 7, the actual vehicle speed oscillates, overshooting and undershooting after acceleration is complete, as shown in Fig. 8, causing the vehicle speed (actual towing speed) to deviate from the predetermined speed (target towing speed) at the release position P of the vehicle 107. This problem becomes more pronounced as the towing rope 101 becomes longer.

[0010] The present invention has been made with an eye on such problems, and aims to solve such problems by feeding back the towing speed from a position that is least affected by the expansion and contraction of the towing rope. [Means for solving the problem]

[0011] In order to achieve the above object, the present invention takes the following measures.

[0012] That is, the vehicle collision test device according to the present invention comprises a tow rope, a drum for towing the tow rope, a plurality of sheaves engaged with the tow rope, a motor for driving the drum, and control means for controlling the motor based on a towing speed command, and a vehicle is connected to a connection point set on the tow rope via a disconnection switching means to perform a collision test, When the vehicle accelerates in any of the acceleration ranges of the early stage, the middle stage, and the final stage of acceleration, the vehicle accelerates in the acceleration range. a sheave speed detection unit is provided on the sheave located closest to the connection point of the vehicle; When the vehicle accelerates in the acceleration range, The sheave speed detected by the sheave speed detector is input to the control means to control the motor.

[0013] This allows the towing speed command to be corrected to the towing speed at the point closest to the vehicle, thereby suppressing vibrations that cause the vehicle speed to overshoot or undershoot after acceleration is complete, thereby suppressing the amount by which the vehicle speed deviates from the specified speed.

[0014] Specifically, it is preferable that the motor is provided with a motor speed detection unit, and the control means controls the motor by feeding back the detected motor speed to the traction speed command, and corrects the traction speed command based on the detected sheave speed.

[0015] With this configuration, the motor is basically controlled by a feedback system configured between the motor speed and the traction speed command. Even if the feedback system is operating properly during acceleration and deceleration, corrections are made based on the sheave speed when the traction rope expands or contracts. With this configuration, the original feedback system includes the motor's transfer function, so appropriate motor control based on the motor's characteristics can be performed while suppressing vibrations that cause the vehicle speed to overshoot or undershoot after acceleration is complete.

[0016] Alternatively, it is preferable that the control means does not feed back the speed of the motor, but feeds back the detected sheave speed to the traction speed command to control the motor.

[0017] With this configuration, the motor is basically controlled by a feedback system formed between the sheave speed and the traction speed command. Therefore, the traction speed command can be directly feedback-controlled based on the nearest sheave speed, with almost no effect from the expansion and contraction of the traction rope. With this configuration, the feedback system does not include the motor's transfer function, so even though optimal control may not be achieved in terms of responsiveness, the feedback system can be configured with as few parts as possible, provided there are no particular problems.

[0018] The present invention is suitable for cases where smoothing control is performed at least at the beginning or end of acceleration.

[0019] In particular, smoothing control is useful for preventing vehicle overshooting and meandering, but if it is affected by the expansion and contraction of the tow rope, not only will its intended effect be lost, but it may even have the opposite effect. Therefore, by applying the present invention, the deviation between the target towing speed and the actual towing speed of the vehicle caused by the expansion and contraction of the tow rope is suppressed, and the effectiveness of smoothing control can be appropriately achieved. [Effects of the Invention]

[0020] According to the present invention as described above, it is possible to provide a vehicle collision test device that can not only suppress the amount by which the vehicle speed deviates from a predetermined speed, but also suppress the vibrations caused by this speed deviation (the actual towing speed of the vehicle being higher or lower than the target towing speed), and can stabilize the posture of the vehicle and a dummy installed inside the vehicle. [Brief explanation of the drawings]

[0021] [Figure 1] 1 is a schematic diagram illustrating the configuration of a vehicle collision test device according to a first embodiment of the present invention. [Figure 2] FIG. [Figure 3] FIG. 4 is a diagram showing an actual vehicle speed relative to a towing speed command. [Figure 4] FIG. 10 is a diagram showing a second embodiment of the present invention. [Figure 5] FIG. 1 is a schematic diagram illustrating the configuration of a conventional vehicle collision test device. [Figure 6] Velocity and acceleration diagrams that are the basis for executing the traction speed command. [Figure 7] FIG. [Figure 8] FIG. 4 is a diagram showing an actual vehicle speed relative to a towing speed command. DETAILED DESCRIPTION OF THE INVENTION

[0022] A first embodiment of the present invention will be described below with reference to the drawings.

[0023] The basic configuration of the vehicle collision test device shown in Figure 1 is the same as that described above with reference to Figure 5, and includes a tow rope 1, a drum 2 that tows this tow rope 1, multiple sheaves 3 that engage with the tow rope 1, a motor 4 that drives the drum 3, and control means 5 that controls the motor 4 based on a towing speed command Vref.The device is configured so that a vehicle 7 is connected to the tow rope 1 via a connection / disconnection switching means 6, the vehicle 7 is caused to run on a running path 8, and then the vehicle 7 is detached by the connection / disconnection switching means 6 and caused to collide with an object 9 at a predetermined speed to conduct a test.

[0024] The towing rope 1 is endless, and in this embodiment, it is wound around a drum 2 located at one end and a return sheave 3A located at the other end, and an intermediate sheave 3B located in the middle portion is engaged with the towing rope 1 at two points and rotates synchronously, so that the towing rope 1 circulates endlessly through winding / releasing by the drum 2.

[0025] A variable speed motor (such as a DC motor or an inverter motor) or a constant speed motor equipped with an acceleration / deceleration device is used as the motor 4 to enable traction at various speeds and accelerations. The motor 4 is provided with a motor speed detection unit 4a.

[0026] The control means 5 retrieves the traction speed command Vref from the memory unit 5b and uses it as an input signal, and also converts the motor speed detected by the motor speed detection unit 4a into an actual traction speed by the conversion unit 5a and feeds it back to the addition / subtraction unit 51. Based on the deviation from the traction speed command Vref, the control means 5 inputs a torque command Tr to the motor 4 through the PI control unit 52.

[0027] In addition to actual vehicles, dummy vehicles are used as vehicle 1. A dolly 6 is placed at connection point C as a connection / disconnection switching means, and vehicle 7 is connected to dolly 6 via a connecting wire 6a. After traveling along travel path 8, vehicle 7 is separated when dolly 6 releases the connection of connecting wire 6a, and then collides with an object 9. Object 9 is an obstacle or another vehicle.

[0028] The control means 5 stores data relating to the velocity diagram and acceleration diagram shown in FIG. 6 in the storage unit 5b, and generates the traction speed command Vref based on this data.

[0029] In order to accelerate the vehicle 7 to a predetermined high speed on the limited length of roadway 8 in accordance with the speed diagram and acceleration diagram of Fig. 6, various conditions are set and stored in memory 5b so that the acceleration is increased to a predetermined value in the early stage of acceleration, a constant acceleration is maintained in the middle stage of acceleration, and then the vehicle accelerates until just before the vehicle separation point in the final stage of acceleration without losing speed, and the acceleration is completed within basic acceleration time A. In this case, in order to stabilize the behavior of the vehicle 7 during towing, a rounding control region is set in the early stage and final stage of acceleration, and control is performed to avoid sudden acceleration and deceleration.

[0030] Specifically, the acceleration is increased to a predetermined value in the early acceleration region t1, and then a constant acceleration is maintained in the middle constant acceleration region t2. Then, in the final acceleration region t3, the vehicle accelerates without dropping speed until just before the vehicle separation position P, and acceleration control is performed along an S-shaped acceleration line as shown in Figs. 6 and 7 as a whole.

[0031] In this configuration, as described above, the vehicle 7 must be accelerated to a predetermined high speed within the limited length of the roadway 8, so the acceleration is large and the tow rope 1 is stretched greatly during acceleration due to its spring constant. When the speed of the vehicle 7 approaches the predetermined target speed and the acceleration is reduced to properly match that speed, the driving force of the motor 4 decreases and the tow rope 1 contracts from its stretched state. Furthermore, if it contracts too much, it will return to its original state and try to extend again.

[0032] For this reason, even if the towing rope 1 is being towed at a predetermined towing speed at the position of drum 2 shown in Figure 1, the expansion and contraction of the towing rope 1 will cause a discrepancy between the speed of the vehicle 7 connected to the towing rope 1 at the position of dolly 6 and the speed of the motor 4 (the actual towing speed at the position of drum 2), and in response to the towing speed command in Figure 7, the actual vehicle speed (measured value) will oscillate, overshooting and undershooting after acceleration is complete, as shown in Figure 8, causing the vehicle speed to deviate from the predetermined speed at the separation position P of the vehicle 7.

[0033] Therefore, in this embodiment, as shown in Figure 1, a sheave speed detection unit 31 is provided on the sheave 3 (intermediate sheave 3B) located closest to the dolly 6 placed at the connection point C of the vehicle 7, and the sheave speed Vs detected by this sheave speed detection unit 31 is input to the control means 5 as an estimated vehicle speed to control the motor 4.

[0034] Specifically, not only is the motor speed fed back to the traction speed command Vref for feedback control, but the detected sheave speed Vs and the traction speed command Vref are input to an adding / subtracting unit 53, and the deviation ε therebetween is input to the adding / subtracting unit 51, thereby correcting the traction speed command Vref.

[0035] When control is performed under this configuration, even if the traction speed V of the towing rope 1 matches the traction speed command Vref at the position of the drum 2 during acceleration or deceleration, if the towing rope 1 is in the process of extending from the drum 2 to the position of the dolly 6, which is the connection point C, and the vehicle 7 is slower than the target speed, a positive deviation ε occurs between the traction speed command Vref and the sheave speed Vs, a positive correction is applied to the traction speed command Vref, and the vehicle 7 is accelerated. Conversely, if the towing rope 1 is in the process of retracting and the vehicle 7 is faster than the target speed, a negative deviation ε occurs between the traction speed command Vref and the sheave speed Vs, a negative correction is applied to the traction speed command Vref, and the vehicle 7 is decelerated.

[0036] That is, according to this embodiment, the motor drive is changed in a direction that compensates for the state in which the vehicle 7 has not yet achieved the desired speed due to the extension or contraction of the towing rope 1.

[0037] As described above, the vehicle collision test device of this embodiment comprises a towing rope 1, a drum 2 that tows the towing rope 1, a plurality of sheaves 3 (3A, 3B) that engage with the towing rope 1, a motor 4 that drives the drum 2, and a control means 5 that controls the motor 4 based on the towing speed command Vref.A collision test is performed by connecting a vehicle 7 to a connection point C set on the towing rope 1 via a dolly 6, which is a connection / disconnection switching means.A sheave speed detection unit 31 is provided on the sheave 3B that is closest to the connection point C of the vehicle 7, and the sheave speed Vs detected by this sheave speed detection unit 31 is input to the control means 5 to control the motor 4.

[0038] In this way, the towing speed command Vref can be corrected to the towing speed at the position closest to the vehicle 7. This operates to suppress vibrations that cause the vehicle speed to overshoot or undershoot after acceleration is complete, and as a result, it is possible to suppress the amount by which the speed of the vehicle 7 deviates from the predetermined speed.

[0039] Furthermore, the vibrations caused by this speed deviation (the actual towing speed of vehicle 7 being higher or lower than the target towing speed) are suppressed, stabilizing the posture of vehicle 7 and suppressing fluctuations in the left-right and front-to-back pitch behavior of vehicle 7 at the start and end of towing acceleration, as well as misalignment of the measurement dummy mounted on vehicle 7, thereby improving the accuracy of the data collected in the crash test.

[0040] Specifically, the motor 4 is provided with a motor speed detection unit 4a, and the control means 5 converts the detected motor speed into an actual traction speed using a conversion unit 4b and feeds it back to the traction speed command Vref to control the motor 4, and also corrects the traction speed command Vref based on the detected sheave speed Vs.

[0041] With this configuration, the motor 4 is basically controlled by a feedback system configured between the motor speed (actual traction speed) and the traction speed command Vref. Even if the feedback system is operating properly during acceleration and deceleration, if the traction rope 1 expands or contracts, a deviation ε occurs between the traction speed command Vref and the sheave speed Vs, and correction is made based on this deviation ε. In this way, the original feedback system includes the motor's transfer function, making it possible to perform appropriate motor control based on the motor's characteristics while suppressing vibrations that cause the vehicle speed to overshoot or undershoot after acceleration is complete.

[0042] In particular, smoothing control is performed when reducing acceleration at the beginning and end of acceleration. The above control suppresses the deviation between the target towing speed and the actual towing speed of the vehicle 7 caused by the expansion and contraction of the towing rope 1, thereby enabling the smoothing control to be performed effectively.

[0043] (Second embodiment) A second embodiment of the present invention will now be described with reference to FIG.

[0044] This embodiment is basically the same as the first embodiment, and comprises a towing rope 1, a drum 2 that tows the towing rope 1, a plurality of sheaves 3 (3A, 3B) that engage with the towing rope 1, a motor 4 that drives the drum 2, and a control means 5 that controls the motor 4 based on a towing speed command Vref.A collision test is performed by connecting a vehicle 7 to a connection point C set on the towing rope 1 via a connection / disconnection switching means, and a sheave speed detection unit 31 is provided on the sheave 3B that is closest to the vehicle connection point C, and the sheave speed Vs detected by this sheave speed detection unit 31 is input to the control means to control the motor 4.

[0045] However, the control means 5 does not feed back the speed of the motor 4, but instead feeds back the detected sheave speed Vs to the traction speed command Vref in the addition / subtraction unit 54 to control the motor 4.

[0046] With this configuration, the motor 4 is basically controlled by a feedback system configured between the sheave speed Vs and the traction speed command Vref. Therefore, the traction speed command Vref can be feedback-controlled directly based on the nearest sheave speed Vs, with almost no effect from the expansion and contraction of the traction rope 1. In this way, since the feedback system does not include the transfer function of the motor 4, it is possible that optimal control will not be achieved in terms of responsiveness, but the feedback system can be configured with as few parts as possible, provided that there are no particular problems.

[0047] Although the embodiments of the present invention have been described above, the specific configurations of the various components are not limited to the above-described embodiments.

[0048] For example, in the above embodiment, the towing rope 1 is stretched between one drum 2 and multiple sheaves 3 (3A, 3B), but it is also possible to wind the towing rope between a pair of winding / releasing drums and a return sheave, and configure the system so that the vehicle is towed and detached via the dolly by driving one drum, and the dolly is returned to its original position by driving the other drum, and connect a motor to the drum and control it with a control means.

[0049] In addition, although the tow rope in the above embodiment is stretched in an oval shape, the form of the stretching and the number of sheaves are not limited, for example, the tow rope may be stretched in a curved state with an intermediate sheave disposed along the way depending on the layout. Even if there are three or more sheaves, if the control of the present invention is performed at the end of acceleration, the sheave closest to the connection point on the travel path at the end of acceleration is specified as one.

[0050] Of course, if it is desired to apply the control of the present invention also at the beginning and middle of acceleration, the sheaves closest to the vehicle on the road at the beginning and middle of acceleration may be different.

[0051] Furthermore, in the above embodiment, the control means employs PI control, but it may employ P control or PID control.

[0052] In the above embodiment, the traction rope is stretched in an endless manner, but it may be in an endless manner.

[0053] Other configurations can also be modified in various ways without departing from the spirit of the present invention. [Explanation of symbols]

[0054] 1...Tow rope 2...Drums 3, 3A, 3B...Sheave 4...Motor 5...Control means 6...Connect / disconnect switching means (dolly) 7...Vehicle 31...Sheave speed detector C...Connection point Vref…Traction speed command Vs…Sheave speed

Claims

1. A crash test device comprising a towing rope, a drum for towing the towing rope, a plurality of sheaves engaged with the towing rope, a motor for driving the drum, and control means for controlling the motor based on a towing speed command, wherein a vehicle is connected to a connection point set on the towing rope via a connection / disconnection switching means, When the vehicle accelerates in any one of an early stage, a middle stage, and a final stage of acceleration, a sheave speed detection unit is provided in a sheave that is closest to a connection point of the vehicle accelerating in the acceleration range, a sheave speed detection unit for detecting a sheave speed when the vehicle accelerates within the acceleration range, the sheave speed being input to the control means to control the motor;

2. 2. The vehicle collision test apparatus according to claim 1, wherein the motor is provided with a motor speed detection unit, and the control means controls the motor by feeding back the detected motor speed to the towing speed command, and corrects the towing speed command based on the detected sheave speed.

3. 2. The vehicle crash test apparatus according to claim 1, wherein said control means controls said motor by feeding back a detected sheave speed to said traction speed command without feeding back the speed of said motor.

4. 4. The vehicle collision test device according to claim 1, wherein smoothing control is performed at least at the beginning or end of acceleration.

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