US 2012/0234787 A1Published application

Method of swing stopping control and system of swing stopping control of suspended load of crane

AssigneeFuji Electric Co., Ltd.

InventorsHideto UEDA, Takayuki Kaneko, Hisashi Yoshizaki

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Abstract

A method of swing stopping control of a suspended load of a crane including a hoist and a trolley solves an equation of motion, given as an equation with respect to the deviation angle of a suspended load from the vertical direction when the trolley travels, for the trolley acceleration to thereby obtain the value of the acceleration or deceleration of the trolley, obtains speed patterns corresponding to the values of the acceleration or deceleration, drives the trolley according to the obtained speed patterns, and carries out control so that the deviation angle of the suspended load from the vertical direction becomes zero at the time when the acceleration or deceleration of the trolley is ended. Thus, even if the length of a rope holding the suspended load up is changed, a required speed pattern is produced to permit highly accurate positioning.

Claims6

Dependent claims

A method of swing stopping control of a suspended load of a crane having a hoist carrying out lifting and lowering of a load suspended by a rope and a trolley traveling on a track while holding the suspended load up, the method comprising:

solving an equation of motion, given below as the equation (1) with respect to the deviation angle of a suspended load from the vertical direction when the trolley travels, for trolley acceleration to thereby obtain the value of one of the acceleration and deceleration of the trolley given below as the expression (2);
obtaining speed patterns corresponding to the values of the one of the acceleration and deceleration;
driving the trolley according to the obtained speed patterns;
and
carrying out control so that the deviation angle of the suspended load from the vertical direction becomes zero at the time when the one of the acceleration and deceleration is ended:
L
r
·

2

θ

t
2
+
2
·

L
r

t
·

θ

t
+
g


θ
=
-
α
(
1
)
where Lr is the lope length, θ is the deviation angle of the suspended load (rope) from the vertical direction, g is the gravitational acceleration and α is one of the acceleration and deceleration of the trolley, and
α

(
t
)
=
[
L
r
g

(
2

π
/
T
s
)
2
-
1
]

α


k
·
cos

(
2

π
T
s
)

t
+
α


k
+
α
k
g
·
2


V
h
·
(
2

π
T
s
)
·
sin

(
2

π
T
s
)

t
(
2
)
where α(t) is one of the acceleration and deceleration of the trolley, Lr is the rope length, g is the gravitational acceleration, Ts is the reference swinging period of the suspended load, αk is one of the reference acceleration and deceleration of the trolley, Vh is the hoist speed and t is the time elapsed from the initiation of one of the acceleration and deceleration.

116 more elements

Dependencies are inferred from the claim text.