JPH0314130B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a towing vehicle speed control system.

In the conventional test water tank, as shown in FIG. 1, a towing vehicle 2 supported by traveling wheels 3 runs on a running rail 1 by a drive motor 4, and the traveling speed of the towing vehicle 2 is as follows. The speed set by the speed setting dial 14 is held as an electric signal in the set speed holding circuit 15, and from this a signal is inputted to the control circuit 16 to run at a predetermined speed, and the control circuit 16 accordingly controls the motor drive circuit. 17, and according to the control signal, the motor drive circuit 17
drives the drive motor 4 with high precision.

On the other hand, in order to accurately monitor the ground speed of the towing vehicle, a speed detection touch roller 11 is kept in contact with the traveling rail 1, and a pulse generator 12 connected to this roller generates a pulse signal proportional to the ground speed. The ground speed signal detected by the ground speed detection circuit 13 is fed back to the control circuit 16, where it is compared with the set speed and corrected to a predetermined set speed. The generated control signal is output to the motor drive circuit 17, and a highly accurate ground speed is maintained.

In addition, the clamp beam 7 attached to the specimen 6
is gripped by a clamp 8 installed on the towing vehicle 2, the towing vehicle 2 and the specimen 6 are made to travel at the same ground speed, and the flow field measurement sensor 9 is moved around the specimen 6 by the flow field measurement sensor support device 10. It is suspended and fixed on the water surface, and accurately measures the flow around the supply body 6 during running.

In the test tank, the tank water 5 is usually not completely still, and the residual flow changes as the test progresses, so it is not appropriate to analyze the measured values based on the ground speed of the test model ship. Therefore, a water speed meter 18 is installed in front of the towing vehicle 2, and its signal is input to the water speed detection circuit 19, which calculates the value of the water speed. It has gained.

However, the residual flow generated in the tank water 5 in the test tank changes depending on the location in the tank and with time, so even if you set the ground speed constant and drive, the water speed will change. Correspondingly, the flow around the specimen 6 also changes.

Therefore, conventionally, the average value of the velocity relative to water within a certain measurement interval is calculated, and analysis is performed based on that value.

However, if this method is used, the error will be small if the residual flow is small, but if the residual flow is large or varies depending on the location, the water speed facing the specimen 6 and the water speed meter This causes a difference in the measured water speed, increasing the measurement error, and since the specimen 6 is always being towed at different water speeds, the phenomenon is not stable, so the measured values are Strictly speaking, this is not a correct value.

The present invention has been proposed in view of the above circumstances, and is a towing vehicle that improves the reliability and accuracy of measurements by controlling the speed of the towing vehicle so that the speed of the specimen relative to the water is constant. A towing vehicle speed control device for a towing vehicle traveling along the longitudinal direction of a water tank and pulling a supply body, the purpose of which is to provide a towing vehicle speed control device for a towing vehicle that runs along the longitudinal direction of a water tank and pulls a supply body, wherein the ground speed of the towing vehicle V _D (t) ground speed detection devices 12 and 13 for detecting the ground speed, and water speed detection devices 18 and 19 for detecting the water speed Vc(t) attached to the towing vehicle at a distance L in front of the specimen; a residual flow velocity calculating device 23 that calculates a residual flow velocity ΔVc(t) which is a speed difference between the water velocity Vc(t) and the ground velocity V _D (t); A part of the residual flow _velocity storage device 24 that stores in time series the ground speed integral value 20 that calculates the time integral value ∫ ^t ₀ V _D (t) dt of the above ground speed, and Ground speed integral value storage device 2 that stores integral values in chronological order
2 and at time T, L=∫ ^T _T- △ _t(T) V _D (t)
A part of the control delay time calculation device 22 that calculates the control delay time Δt(T) corresponding to dt and the time T−Δt based on the stored residual flow velocity ΔV _c (t).
Correction residual flow velocity △V _c [T-△t
(T)], the correction residual flow velocity △V _c [T-△t(T)], the ground speed V _D (t), and the towing vehicle. The towing vehicle speed control device is characterized in that it includes a part of the control device 24 and 16 for calculating the traveling speed of the towing vehicle based on the speed setting values 14 and 15.

An embodiment of the present invention will be explained with reference to the drawings.
FIG. 2 is a block diagram of the control circuit.

In the above figure, the same symbols as in Fig. 1 indicate the same equipment and members as in the figure, respectively: 20 is the ground speed integration circuit, 21 is the position setting switch, 22 is the control delay time calculation circuit, and 23 is the residual flow velocity. The arithmetic circuit 24 is a corrected speed arithmetic circuit.

In the above figure, a ground speed integration circuit 20 is connected to the ground speed detection circuit 13, and its output is input to a control delay time calculation circuit 22. The output of the position setting switch 21, which inputs the distance L between the water speed meter 18 and the test model ship 6, is also input to the control delay time calculation circuit 22, and the output of this circuit is input to the corrected speed calculation circuit 24. In addition, the outputs of the set speed holding circuit 15 and the residual flow velocity calculation circuit 23 are input to the corrected speed calculation circuit 24, the output of the corrected speed calculation circuit 24 is input to the control circuit 16, and the output of the ground speed detection circuit 13 is inputted. The output is also input to the residual flow velocity calculation circuit 23. The control circuit 16 has a built-in switch (not shown) for switching between controlling based on ground speed and water speed.

In such a device, the distance between the specimen 6 and the water velocity meter 18 is L, and the intended water velocity of the specimen 6 is
Vc, the ground speed of the towing vehicle obtained by the ground speed detection circuit 13 at time t, V _D (t), the towing vehicle at the position of the water speed meter 18 in the water tank obtained by the water speed detection circuit 19; Vc
(t), and the residual flow velocity is △ _vc (t).

Then, the water speed vc (t 1 ) detected by the water speed meter 18 at ^a certain time t ₁ after the towing vehicle 2 shifts to steady running is Vc (t ₁ ) = V _D (t ¹ ) +△ _Vc (t ₁ ) …(1) △ _Vc (t ₁ )−V _D (t ₁ ) …(2) After this, the towing vehicle 2 travels a distance L, and the position of the water speed meter 18 at t ₁ If the time when the specimen 6 reaches _t2 is L=∫ _t2t1 V _D (t) dt...(3), and in order to set the water velocity of the specimen 6 at this time to Vc, the towing The ground speed of pulling vehicle 2 must be V _D (t ₂ ) = Vc - △ _Vc (t ₁ )...(4).

Here, the residual flow flows from the position of the current meter 18 to the specimen 6.
The time required to reach the position (t ₂ - t ₁ ) is the control delay time.

In the present invention, the residual flow velocity calculation circuit 23 calculates residual flow based on the water velocity Vc (t) output from the water velocity detection circuit 19 and the ground velocity V _D (t) output from the ground velocity detection circuit 13. The flow velocity △ _Vc (t) is calculated and output to the corrected speed calculation circuit 24.
Now, this signal is stored in a storage device in chronological order.

On the other hand, the ground speed V _D (t) output from the ground speed detection circuit 13 is integrated in the ground speed integration circuit 20, and the value ∫ _t0 V _D (t)dt is output to the control delay time calculation circuit 22.

The control delay time calculation circuit 22 stores the value of ∫ _t0 V _D (t)dt in time series, and inputs the relative distance value L from the position setting switch 21, so that at a certain time T
, Δt(T) is calculated such that L=∫ _{TT- Δt(T)} V _D (t)dt, and this is output to the corrected speed calculation circuit 24 as the control delay time at time T.

The corrected speed calculation circuit 24 calculates △V D as the corrected speed at a certain time T from the residual flow rate △V _D (t) input and stored from the residual flow rate _calculation circuit 23.
Extract the value of [T-△ _t (T)] and subtract it from the input V _D from the set speed holding circuit 15. Formula (5) V _D = Vc-△ _Vc [T-△ _t (T)] ...(5) is performed and this value is output to the control circuit 16 as the corrected speed.

In the case of control based on water speed, the control circuit 16 receives this signal and controls the motor drive circuit 17 to cause the towing vehicle 2 to travel, and in the case of control based on ground speed, it performs the same control as the conventional one. Do this.

As described above, in the present invention, based on the water speed detected by the water speed meter 18, at any position input from the position setting switch 21, the water speed is set at the speed set by the speed setting dial 14. Since the flow rate is controlled so that the velocity relative to the water is always constant, the flow around the specimen 6 can be precisely measured.

Note that the present invention can also be applied to the verification of current meters.

In short, according to the present invention, in a towing vehicle speed control device for a towing vehicle that travels along the longitudinal direction of a water tank and pulls a specimen, the towing vehicle's ground speed V _D
(t) ground speed detection devices 12 and 13 that detect
Water speed detection devices 18 and 19 are attached to the towing vehicle at a distance L in front of the specimen and detect the water speed Vc(t), and the water speed Vc(t) and the ground speed V _D Residual flow velocity △Vc which is the velocity difference from (t)
(t), a part of the residual flow velocity storage device 24 that stores the residual flow velocity ΔVc(t) in time series, and the time integral value of the ground velocity V _D ∫ ^t ₀ V _D (t) Ground speed integral value 2 to calculate dt
0, a part of the ground speed integral value storage device 22 that stores the above-mentioned ground speed integral value in chronological order, and time T.
A control delay time calculation device that calculates a control delay time △t(T) corresponding to L=∫ ^T _T- △ _t(T) V _D (t) dt based on the stored integral value of the ground speed. 22 and the stored residual flow velocity △V _c
(t), a part of the correction speed calculation device 24 that calculates the correction residual flow velocity △V _c [T-△t(T)] corresponding to the time T-△t(T), and Residual flow velocity △V _c [T - △t (T)] and the above ground speed V _D (t)
and the speed setting values 14 and 15 of the towing vehicle,
The present invention provides a towing vehicle speed control device with high accuracy by using a towing vehicle speed control device characterized in that it includes a portion of the control device 24 and 16 for calculating the traveling speed of the towing vehicle. is extremely useful for industry.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a known speed control device for a towing vehicle for a test aquarium, and FIG. 2 is a block diagram showing an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1...Traveling rail, 2...Tow truck, 3...Traveling wheel, 4...Drive motor, 5...Aquarium water, 6...
... Specimen, 7 ... Clamp beam, 8 ... Clamp, 9 ... Flow field measurement sensor, 10 ... Flow field measurement sensor support device, 11 ... Touch roller, 1
2...Pulse generator, 13...Ground speed detection circuit, 14...Speed setting dial, 15...Set speed holding circuit, 16...Control circuit, 17...Motor drive circuit, 18...Water speed meter , 19...Water speed detection circuit, 20...Ground speed integration circuit, 21...
... Position setting switch, 22 ... Control delay time calculation circuit, 23 ... Residual flow speed calculation circuit, 24 ... Correction speed calculation circuit, Vc ... Water speed, V _D ... Ground speed.

Claims (1)

[Scope of Claims] 1. In a towing vehicle speed control device for a towing vehicle that travels along the longitudinal direction of a water tank and pulls a specimen, a towing vehicle speed control device for detecting a ground speed V _D (t) of the towing vehicle; A distance L is placed in front of the speed detection devices 12 and 13 and the specimen.
The water speed detection devices 18 and 19 attached to the towing vehicle detect the water speed Vc (t), and the speed difference between the water speed Vc (t) and the ground speed V _D (t). a residual flow velocity calculation device 23 that calculates a certain residual flow velocity ΔVc(t); a residual flow velocity storage device (part of 24) that stores the residual flow velocity ΔVc(t) in time series; A ground speed integral value 20 for calculating the time integral value of ground speed V _D ∫ ^t ₀ V _D (t) dt and a ground speed integral value storage device (one part of 22) that stores the above-mentioned ground speed integral value in time series. part), at time T, calculate the control delay time △t(T) corresponding to L=∫ ^T _T- △ _t(T) V _D (t) dt based on the stored integral value of the above ground speed. Control delay time calculation device (part of 22) and the stored residual flow velocity △V _c
a correction speed calculation device (a part of 24) that calculates a correction residual flow velocity △V _c [T-△t(T)] corresponding to time T-△t(T) based on (t); Correction residual flow velocity △V _c [T-△t(T)] and the above ground speed V _D
(t) and a speed setting value 14, 15 of the towing vehicle, the towing vehicle is characterized by comprising a control device (a part of 24 and 16) that calculates the traveling speed of the towing vehicle. Speed control device.