JPH09110373A - Zero point compensating method of swing angle sensor for swing preventing control - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a zero point compensating method of a swing angle sensor for swing preventing control angle sensor, dispensing with any zero point variation in this sensor, and offering such a sensor as capable of detecting a highly accurate swing angle. SOLUTION: In this swing angle sensor for swing preventing control to detect a deviation angle after combining two sensors installed both fixed and movable sides together for detecting the swing angle with a lifting load, an extent of sensor output being contained in an output part of the sensor 6 at the fixed side is separated of its DC part alone with a filter, through which a zero point of the swing angle sensor is compensated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a zero-point correction method of a shake angle sensor for steady rest control, and in particular, it is effective in eliminating the zero point variation of the shake angle sensor and achieving a steady rest control accuracy. The present invention relates to a zero-point correction method for a shake control deflection angle sensor.

[0002]

2. Description of the Related Art Conventionally, for detecting the deflection angle of a suspended load by a crane or the like, as shown in FIG. When hanging a load by hoisting or lowering the rope, a fixed-side sensor 6 fixed to a girder or a club of a crane and a movable-side sensor 4 movably attached to a mounting bracket so as to be tilted together by tilting of the load. And a sensor rope 3 having one end fastened to the movable sensor, and a sensor rope winding motor 2 that winds the other end of the sensor rope to keep the tension of the sensor rope constant. There is. Therefore, in the conventional deflection angle sensor configured as described above, when the suspended load 1 swings, the movable side that can freely tilt through the sensor rope 3 that is given a constant tension to the sensor rope winding motor 2 The sensor 4 tilts, and an output proportional to the tilt angle θ is obtained.

[0003]

In the conventional steady-state control deflection angle sensor described above, when the suspended load 1 swings, the movable side sensor 4 that follows the swing load 1 also tilts, and an output proportional to this tilt angle θ is obtained. However, this is true only in the static state. However, the internal structure of the movable side sensor 4 has a small pendulum inside the sensor, and this pendulum tilts and converts this amount into an electric signal. Therefore, in addition to the swing angle θ of the suspended load 1, the crane 5 Since the traveling acceleration α of the moving sensor 4 is input to the movable side sensor 4, the pendulum inside the sensor 4 also reacts to this acceleration α, and the movable side sensor 4 alone detects the swing angle θ of the suspended load 1 with high accuracy. Is impossible. As a countermeasure against this, in the prior art, the fixed side sensor 6 is combined. That is, the acceleration α of the crane 5 is input to both the moving-side sensor 4 and the fixed-side sensor 6, so if the difference between the sensor outputs of both is taken, the output by α becomes 0, and only θ is obtained as the output value. It is composed. However, the basic principle of this method is that the mounting surface of the fixed-side sensor 6 does not change its inclination while the deflection angle sensor is in use, but since the crane moves on the traveling rail during operation, Due to the level change of the rail, the fixed side sensor mounting surface is inclined by Δ, so that the deflection angle sensor output becomes θ−Δ instead of θ, and the sensor zero point fluctuation occurs. That is, the movable side sensor output Θ1
Is Θ1 = θ + f (α) (1) Fixed-side sensor output Θ2 is Θ2 = f (α) + Δ (2) Θ0 = Θ1-Θ2 = θ + f (α)-{f (α) + Δ} = θ-Δ (3) Here, θ is the deflection angle of the suspended load f (α): Sensor output fluctuation due to crane acceleration Δ: Fixed-side sensor inclination angle α: Crane acceleration θ0: Deflection angle sensor output. Therefore, if the mounting surface of the reference side deflection angle sensor is tilted during operation, the deflection angle sensor will change as it is at 0 point, and there is a problem that there is a limit to improving the precision of the steady stop control. It is an object of the present invention to provide a zero-point correction method for a shake-prevention shake angle sensor, which eliminates the zero-point fluctuation of the shake angle sensor and provides a sensor capable of highly accurate shake angle detection.

[0004]

In order to achieve the above object, a method of correcting a zero point of a shake angle sensor for steady-state control according to the present invention is a DC output using a filter for a sensor output included in a sensor output of a fixed side. It is characterized in that only the minute is separated and the zero point of the shake angle sensor is corrected.

According to the zero-point correction method of the steady-state control shake angle sensor of the present invention having the above-mentioned structure, the output of the mounting surface inclination is separated from the detected value of the reference side shake angle sensor by combining a filter, and this value is separated. Since the zero point fluctuation of the shake angle sensor is corrected by the above, the zero point fluctuation of the shake angle sensor can be eliminated, and the shake angle can be detected with high accuracy.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a zero-point correction method for a steady-angle control shake angle sensor according to the present invention will be described below with reference to the drawings.

In the figure, reference numeral 1 is a suspended load, and this suspended load 1 winds a suspended load wire rope 8 around which a hook 7 is stretched around a winding drum 9 to suspend the suspended load 1 and also a crane girder or The fixed side sensor 6 is fixed to the club, the movable side sensor 4 is movably attached to the mounting bracket so as to be tilted together with the tilt of the suspended load, and the other end side of the sensor rope 3 having one end fastened to the movable side sensor. Is wound around the sensor rope winding motor 2, and the tension of the sensor rope is always kept constant.

Therefore, when the suspended load 1 swings, the movable side sensor 4 which can freely tilt through the sensor rope 3 which is given a constant tension to the sensor rope winding motor 2 tilts, and is proportional to the tilt angle θ. Output is obtained. However,
The states described above can be established only in the static state. Therefore, since the traveling acceleration α of the crane 5 is input to the movable side sensor 4 in addition to the deflection angle θ of the suspended load 1,
The pendulum inside the sensor 4 also reacts to this acceleration α, and it is impossible for the movable sensor 4 alone to detect the swing angle θ of the suspended load 1 with high accuracy. Therefore, the fixed-side sensor 6 is combined, the acceleration α of the crane 5 is input to both the moving-side sensor 4 and the fixed-side sensor 6, the difference between the sensor outputs of both sensors is taken, and the output component due to the acceleration α of the crane 5 is output. Is set to 0 so that only θ can be obtained as an output value.

The zero point fluctuation of this deflection angle sensor, the above (3)
In the formula, Δ component has been a major obstacle in performing high-precision steady rest control. As a countermeasure against this, as is apparent from the equation (2), the 0-point variation Δ is combined with the f (α) component in the output of the fixed-side sensor output Θ2, and from this, Δ
Separate this through a filter to extract only
Is added to the equation (3) so that Θ0 = θ.

A zero-point correction circuit of the deflection angle sensor of the present invention is shown in FIG. The acceleration α of the crane acting on the fixed-side sensor 6 is a combination of the command acceleration β from the traveling control device and the noise component, that is, the vibration acceleration δ (t) generated by the deflection of each part of the crane, and is given by the following formula. α = β + δ (t) (4) where β: commanded acceleration δ (t): vibrational acceleration. Therefore, the output waveform of the fixed-side sensor output Θ2 is as shown in FIG.

Therefore, the output Θ through the noise filter is
3 is

(Equation 1) And the smooth waveform shown in FIG. 4 is obtained.

In order to separate the direct current component, that is, Δ in FIG. 4, the following method is adopted. That is, since the command acceleration β is known, the theoretical deflection angle model f
From (β), the theoretical deflection angle is calculated, and the following theoretical formula is obtained through a filter.

(Equation 2) Here, f (β): theoretical deflection angle obtained by commanded acceleration Θ4: theoretical deflection angle through a filter

This is shown in FIG. 5, which does not include Δ. Therefore, the difference Θ5 between the output Θ3 through the noise filter and the theoretical deflection angle Θ4 through the filter is

(Equation 3) Δ is Θ5≈Δ for the DC component and has the value shown in FIG. 6, which means that the 0-point variation Δ is separated from the fixed-side sensor output Θ2.

Therefore, the corrected output .THETA.6 is: .THETA.6 = .THETA.0 + .THETA.5 = .THETA .-. DELTA. +. DELTA. =. THETA.

[0015]

According to the steady angle control deflection angle sensor of the present invention, even if the entire crane is tilted due to the level change of the traveling rail, the zero point fluctuation of the deflection angle sensor does not occur, and accurate deflection angle detection is possible. It becomes possible and highly accurate steady rest control becomes possible.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a first embodiment of a steady-angle control shake angle sensor of the present invention.

FIG. 2 is a block diagram showing a zero point variation correction control method of the present invention.

FIG. 3 is an output waveform diagram at the stage of separating 0-point variation.

FIG. 4 is an output waveform diagram at a stage of separating 0-point variation.

FIG. 5 is an output waveform diagram at the stage of separating 0-point variation.

FIG. 6 is an output waveform diagram at the stage of separating 0-point variation.

[Explanation of symbols]

 1 Suspended Load 2 Sensor Rope Winding Motor 3 Sensor Rope 4 Movable Side Sensor 5 Crane 6 Fixed Side Sensor 7 Hook 8 Wire Rope 9 Winding Drum

Claims (1)

[Claims] 1. A steady-state deflection deflection angle sensor for detecting a deflection angle of a suspended load by combining a fixed side sensor and a movable side sensor, the sensor output included in the fixed side sensor output. Is corrected by using a filter to separate only the direct current component, and the zero point of the shake angle sensor is corrected.