Device and method for measuring the parameters of angular movements of a lifting machine rope

Claims

1. A device for measuring the parameters of angular movements of a rope of a lifting machine, in the body of which a collar is built in, through which the rope is passed, and the body of the device is also secured by means of a hinged or flexible connection to the body of the lifting mechanism of the crane, inside the body of the device there are installed two micromechanical accelerometers with a sensitivity axis perpendicular to the rope and directed along the axes of movement of the load, connected with the coordinate system of the crane, a microcontroller for processing signals from the accelerometers, an interface unit for transmitting data from the microcontroller to the crane control system via a wired or wireless communication channel, characterized in that it additionally contains two angular velocity sensors with axes of sensitivity perpendicular to the rope and corresponding to the axes of movement of the load, connected with the coordinate system of the crane.

2. A method of using a device for measuring the parameters of angular movements of a rope of a lifting machine, which involves the initial setting of the sensors used, characterized in that Using built-in accelerometers, the established angles of inclination of the rope and their predictions due to the action of an external force on the load are determined according to the relationship: , Where - the established angle of deviation of the rope from the vertical and its forecast due to the action of an external force on the load, corresponding to the k-th axis of movement of the load, k = 1, 2; this angle is necessary to correct the position of the load in the horizontal plane; - current accelerometer readings with a sensitivity axis along the k-th axis of load movement, filtered on a low-pass filter to eliminate high-frequency measurement interference; - the accelerometer zero offset determined at the stage of its initial alignment along the k-th axis of load movement; g - acceleration of gravity; Using built-in angular velocity sensors, angular velocities and general rope tilt angles are determined using the following dependencies: , where ω k - angular velocity of the rope corresponding to the k-th axis of movement of the load; - output signal of the angular velocity sensor corresponding to the k-th axis of load movement; - angular velocity drift, determined at the stage of initial alignment of the angular velocity sensors, corresponding to the k-th axis of load movement; - the current value of the total angle of deviation of the rope from the vertical, corresponding to the k-th axis of movement of the load; - initial value of the angle after the initial exhibition and adjustment of the rope angle readings; t is the current time, and t0 is its initial value after the initial setting and adjustment of the rope tilt angle readings; the deflection angles of the load rope corresponding to free vibrations are determined by the dependence , Where - the angle of deviation of the rope from the vertical axis, caused by the free oscillatory motion of the load, corresponding to the k-th axis of movement of the load; this angle, together with ω k necessary for organizing vibration damping; - low-frequency part of the signal , which approximately describes the actual deviation of the suspension cable from the vertical axis due to the action of an external force; carry out adjustments to the readings of the current values ​​of the inclination angles of the cargo rope, according to the ratios that change the parameters : Where - denotes the filtering of the output module of the angular velocity sensor corresponding to the k-th axis of load movement, on a real differentiating link with an assigned filter time constant T ф ; - differentiation operator; - selected small positive numbers corresponding to angular and linear accelerations, indicating, if the specified inequalities are valid, that the rope is in a steady vertical state; symbol " " denotes the condition "identically less than over period τ", i.e. the variable is less than the specified value identically over a time interval of duration no less than the specified τ.

3. The device according to paragraph 1, characterized in that for each axis of sensitivity of the accelerometers and each axis of sensitivity of the angular velocity sensors, not one accelerometer or one angular velocity sensor is used, but a group of them connected to a microcontroller.

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