Patent classifications
B66C13/063
Controller for a lifting device, and method for operating same
A controller controls a plurality of drives of a lifting device, wherein the controller is configured to perform a kinematic transformation of spatial position and orientation coordinates of a body and controls the drives based on the kinematic transformation. The drives can be electric drives. At least six drives are provided and regulated, so that their number exceeds the number of spatial position and orientation coordinates of the body. The lifting device is thus overdetermined.
LQR-based anti-sway control method and system for lifting system
The present invention provides a linear quadratic regulator (LQR)-based anti-sway control method for a hoisting system, comprising the following steps: obtaining a target position of a trolley, and obtaining a planned real-time path of the trolley according to the maximum velocity v.sub.m and maximum acceleration a.sub.m of the trolley; establishing a dynamic model of the hoisting system according to a Lagrange's equation, for the Lagrange's equation, the trolley displacement x, the spreader sway angle θ, and the rope length l of the hoisting system being selected as generalized coordinate directions; observing lumped disturbance d using an extended state observer, and compensating for same in a controller, the lumped disturbance d comprising the dynamic model error and external disturbance to the hoisting system; tracking the planned real-time path of the trolley by a Q matrix and an R matrix using a linear quadratic regulator controller. The LQR-based anti-sway control method for a hoisting system provided by the present invention can make the hoisting system operate more smoothly, reduce sway during operation, and quickly eliminate sway when in place while observing the lumped disturbance using an extended state observer.
CARGO CRANE, CARGO-CRANE SWING PREVENTION METHOD, AND CARGO CONVEYANCE METHOD
A cargo crane including an arm turning mechanism that turns a crane arm; an arm luffing mechanism that adjusts the luffing angle; an arm extension and contraction mechanism that adjusts the arm length; and a control device that calculates a trajectory in which a suspended cargo is conveyed, and that controls the mechanisms. The control device calculates the trajectory so as to be a straight line trajectory as viewed from at least the vertical direction; calculates a turning angle θ, a luffing angle φ, and an arm length L so as to cause the trajectory to be the straight line trajectory by using the cargo start position, the cargo target position, a maximum speed v.sub.max, a suspended cargo swing cycle T, and a start-up time T.sub.1; and controls the mechanisms so as to achieve the calculated turning angle θ, luffing angle φ, and arm length L.
When performing the conveyance from an arbitrary cargo start position to an arbitrary cargo target position, it is possible to control swing prevention without constraint condition and with a simple control system. There is provided a cargo crane including an arm turning mechanism (4) that turns a crane arm (2); an arm luffing mechanism (3) that adjusts the luffing angle; an arm extension and contraction mechanism (5) that adjusts the arm length; and a control device that calculates a trajectory in which a suspended cargo (7) is conveyed, and that controls the arm turning mechanism (4), the arm luffing mechanism (3), and the arm extension and contraction mechanism (5). The control device calculates the trajectory so as to be a straight line trajectory as viewed from at least the vertical direction, according to the cargo start position and the cargo target position; calculates a turning angle θ, a luffing angle φ, and an arm length L so as to cause the trajectory to be the straight line trajectory by using the cargo start position, the cargo target position, a maximum speed v.sub.max, a suspended cargo swing cycle T, and a start-up time T.sub.1; and controls the arm turning mechanism (4), the arm luffing mechanism (3), and the arm extension and contraction mechanism (5) so as to achieve the calculated turning angle θ, luffing angle φ, and arm length L.
DYNAMIC LIFT-OFF CONTROL DEVICE, AND CRANE
A dynamic lift-off control device that is mounted on a crane including a boom and a winch for winding a wire rope and that controls dynamic lift-off of a suspended load, wherein: the dynamic lift-off control device comprises a load detection unit that detects a load acting on the boom, and a control unit that controls a winding action of the winch and a hoisting action of the boom; and the control unit controls the hoisting of the boom by using a control signal, which is generated on the basis of the change over time in the value detected by the load detection unit and to which a filter for attenuating a frequency component in a prescribed range, to suppress swaying of the suspended load is applied.
Crane
A crane is provided. A slewing base camera detects a load W that is suspended by a wire rope, the current coordinate location of the load is calculated from the location of the detected load, the current coordinate location of a tip end of a boom is calculated from the position of a crane, a target velocity signal that was inputted from a manipulation tool is converted into a target coordinate location of the load, a wire rope direction vector is calculated from the current coordinate location of the load and the target coordinate location of the load, a target location of the tip end of the boom for the target coordinate location of the load is calculated from a wire rope reel-out amount and the wire rope direction vector, and an actuator operation signal is generated.
Crane and method for acquiring length of slinging tool
This crane is provided with: a boom; a wire rope suspended down from a leading end section of the boom; a suspender that is fixed to a lower end of the wire rope and is for suspending a slinging tool for hanging a load; a calculation unit that calculates a first load, which is the weight of a member that is suspended down from the suspender; a slinging tool database unit that stores information pertaining to the slinging tool corresponding to the first load; a determination unit that determines whether a load is being suspended from the suspender; and a control unit that acquires the information pertaining to the slinging tool corresponding to the first load from the slinging tool database unit if the load is being suspended, and sets the vertical length of the slinging tool on the basis of the acquired information pertaining to the slinging tool.
WORK MACHINE CONTROL SYSTEM AND CRANE
This control system comprises: a signal processing unit generating a signal related to the target operating amount of an actuator; a feedback control unit that controls the actuator based on the difference between the signal related to the target operating amount and a signal related to the fed-back operating amount; a feed-forward control unit that controls the actuator based on the signal related to the target operating amount in cooperation with the feedback control unit, and learns the characteristics of the actuator by adjusting a weighting factor based on a teacher signal; and a calculation unit that calculates information related to the deflection of the work machine. The signal processing unit corrects intermediate information, which is generated in the process of generating the signal related to the target operating amount, based on the information related to the deflection, and generates the signal related to the target operating amount.
DYNAMIC FLEX COMPENSATION, COORDINATED HOIST CONTROL, AND ANTI-SWAY CONTROL FOR LOAD HANDLING MACHINES
Various example embodiments relate to motion control of a target such as a suspended load. An apparatus may comprise: a floating base comprising an exteroceptive observation system configured to measure a position or velocity of at least one target with respect to a reference coordinate frame moving with the floating base. The floating base may further comprise an inertial measurement unit configured to measure at least one inertial state of the floating base with respect to an inertial reference coordinate frame. Position or velocity compensation for the at least one target may be performed based on the at least one inertial state of the floating base.
Device for stabilizing a hoisted object
Disclosed are various embodiments for stabilizing a hoisted object. A hoisted object such as a litter can have a tendency spin while being retrieved on a lift line. A device may be connected to the hoisted object to reduce a spin or other angular velocity of the hoisted object. The device may monitor stability of the hoisted object and determine that the hoisted object is unstable. The device may be configured to rotate at least one flywheel to apply torque to an enclosure of the device.
First-order dynamic sliding mode variable structure-based bridge crane anti-swing method
A bridge crane anti-swing method based on first-order dynamic sliding mode variable structure includes steps of: constructing a two-dimensional bridge crane system model and a crane system control model, respectively; performing differentiation on two sliding mode surfaces containing swing angle dynamic change and rope length dynamic change to obtain a crane position dynamic sliding surface s1 and a rope length dynamic sliding mode surface s2, respectively; combining a displacement x, a length l and a swing angle θ in the two-dimensional bridge crane system model with the crane position dynamic sliding surface s1 and rope length dynamic sliding mod surface s2 in the crane system control model to obtain a relationship among a horizontal traction force f1, an along-rope traction force f2, the displacement x, the length l and the swing angle θ.