Offshore crane heave compensation control system and method using visual ranging

Patent metadata

Field	Value
Publication number	US-2018370775-A1
Application number	US-201616064458-A
Country	US
Kind code	A1
Filing date	Dec 22, 2016
Priority date	Dec 22, 2015
Publication date	Dec 27, 2018
Grant date	—

Abstract

Provided is an offshore crane heave compensation control system and method using video rangefinding to achieve heave compensation in a directly driven pump-controlled electro-hydraulic heave compensator. The heave compensation and the heave compensator are applicable for special operation and control requirements on a fixed offshore platform and allow the crane to achieve steady lifting of a load away from or lowering of a load on to a supply vessel without being influenced by the motion of the supply vessel caused by ocean currents, ocean winds, or ocean waves. Also provided is a test platform for the offshore crane heave compensation control system using video rangefinding. The test platform provides a realistic simulation for all lifting and lowering processes of an offshore platform crane in offshore environments to study the motion control of the provided system.

First claim

1 .- 28 . (canceled)

29 . An offshore crane heave compensation control system using visual ranging, comprising:
a detecting device, a controlling device and actuating device, the heave compensation control system is to achieve heave compensation movement automatically while the offshore crane is loading down and up cargo to the supply vessel, by adding the movement of supply vessel with the same direction and amplitude to the offshore crane, in order to load down and up the cargo to the supply vessel stably, under the condition of ocean waves, the offshore crane can achieve loading down and up the cargo to a supply vessel without being influenced by the heave motion caused by the ocean currents, sea wind or ocean waves; wherein: the detecting device detects the three-dimensional position information of the supply vessel using visual ranging method, transmits the detected parameters of three-dimensional position information to the controlling device, the controlling device controls the actuating device to achieve heave compensation movement automatically while the offshore crane is loading down and up cargo to the supply vessel, by adding the movement of supply vessel with the same direction and amplitude to the offshore crane, in order to load down and up the cargo to the supply vessel stably, under the condition of ocean waves, the offshore crane can achieve loading down and up the cargo to a supply vessel without being influenced by the motion caused by the ocean currents, sea wind or ocean waves; the offshore platform is a fixed offshore platform; the three-dimensional position information means displacement, velocity and acceleration information in various directions which is referred to a rectangular coordinate system including the heave direction and the three-dimensional attitude of the supply vessel; and the movement with the same amplitude and same direction means the supply vessel motion along with the periodic motion of the ocean waves with the same amplitude and same direction.

30 . The offshore crane heave compensation control system using visual ranging of claim 29 , wherein: during the loading up stage, the detecting device detects the heave motion information of the supply vessel using visual ranging method, and the controlling device computes the velocity and acceleration information of the supply vessel, the actuating device adds the motion of the same amplitude and the same direction of the supply vessel heave motion to perform active heave motion compensation and choose the right time to load up, as to avoid the impact loads of the crane wire ropes and achieve loading up the load steadily.

31 . The offshore crane heave compensation control system using visual ranging of claim 29 , wherein: during the loading down stage, the detecting device detects the three-dimensional position information of the supply vessel using a visual ranging method, under the control of the controlling device, the actuating device adds the motion of the same amplitude and the same direction of the supply vessel heave motion during the loading down stage, to ensure that the load is down to the vessel deck at a relative setting speed; furthermore, the supply vessel attitude information can be judged, the right time to loading down can be selected, as to achieve loading down the load steadily.

32 . The offshore crane heave compensation control system using visual ranging of claim 29 , wherein: the actuating device is a direct pump control electro-hydraulic heave compensation device ( 3 ) which includes a servo motor driver ( 4 ), a rotation speed sensor ( 5 ), a displacement sensor ( 7 ), and an at least three pressure sensors ( 6 ); The servo motor driver ( 4 ) drives the direct pump control electro-hydraulic heave compensation device ( 3 ); The rotation speed sensor ( 5 ), the displacement sensor ( 7 ), and at least three pressure sensors ( 6 ) collect the operating parameters of the direct pump control electro-hydraulic heave compensation device ( 3 ) and feed them back to the control system, as to achieve a closed-loop control of the direct pump control electro-hydraulic heave compensation device ( 3 ), in order to load down and up the load steadily and stably.

33 . The offshore crane heave compensation control system using visual ranging of claim 32 , wherein: the direct pump control electro-hydraulic heave compensation device ( 3 ) which includes a servo motor driver ( 4 ), a servo motor ( 16 ), a two-way hydraulic pump ( 17 ), an accumulator ( 13 ), and a quick connector ( 14 ), two overflow valves ( 15 ), a single rod hydraulic cylinder ( 11 ), a movable pulley ( 9 ), a static pulley ( 10 ), at least three pressure sensors ( 6 ), a rotation speed sensor ( 5 ), and a displacement sensor ( 7 ); The servo motor driver ( 4 ) drives the servo motor ( 16 ) to rotate the two-way hydraulic pump ( 17 ); Two output terminals of the two-way hydraulic pump ( 17 ) are connected to a rod chamber and a rodless chamber of the single rod hydraulic cylinder ( 11 ) respectively through the hydraulic pipeline. Two oppositely mounted overflow valves are connected in parallel between the two output terminals of the two-way hydraulic pump ( 17 ); The servo motor ( 16 ) is connected to the rotation speed sensor ( 5 ); The rotation speed sensor ( 5 ), the displacement sensor ( 7 ), servo motor driver ( 4 ), and at least three pressure sensors ( 6 ) are respectively connected to the control computer ( 1 ). The movable pulley ( 9 ) is connected to the piston rod of the single rod hydraulic cylinder ( 11 ); The static pulley ( 10 ) is connected to the bottom of the single rod hydraulic cylinder ( 11 ); The displacement sensor ( 7 ) is installed in the single rod hydraulic cylinder ( 11 ).

34 . The offshore crane heave compensation control system using visual ranging of claim 33 , wherein: the servo motor driver ( 4 ), the servo motor ( 16 ), the two-way hydraulic pump ( 17 ), the accumulator ( 13 ), the quick connector ( 14 ), the two overflow valves ( 15 ), the single rod hydraulic cylinder ( 11 ), the movable pulley ( 9 ), the static pulley ( 10 ), at least three pressure sensors ( 6 ), the rotation speed sensor ( 5 ), and displacement sensor ( 7 ) are integrated into an autonomous device.

35 . The offshore crane heave compensation control system using visual ranging of claim 33 , wherein: the movable pulley ( 9 ), the piston rod of the single rod hydraulic cylinder ( 11 ) and the static pulley ( 10 ) of the direct pump control electro-hydraulic heave compensation device ( 3 ) are located on the same axis.

36 . The offshore crane heave compensation control system using visual ranging of claim 33 , wherein: after the first way of the accumulator ( 13 ) of the direct pump control electro-hydraulic heave compensation device ( 3 ) is connected to one terminal of two oppositely mounted pilot operated check valve ( 18 ), the other terminal of the two oppositely mounted pilot operated check valve ( 18 ) is connected in parallel between the two terminals of the two-way hydraulic pump ( 17 ).

37 . The offshore crane heave compensation control system using visual ranging of claim 33 , wherein: the accumulator ( 13 ) is divided into three ways, the first way is connected to the rod chamber side of the single rod hydraulic cylinder ( 11 ), the second way is connected to the quick connector ( 14 ), and the third way is connected to the first pressure sensor ( 6 ), the two output terminals of the two-way hydraulic pump ( 17 ) are connected to the second pressure sensor ( 6 ) and the third pressure sensor ( 6 ).

38 . The offshore crane heave compensation control system using visual ranging of claim 29 , wherein: the controlling device is a control compu

Assignees

• Univ Zhejiang

Inventors

• Gong Guofang
• Zhang Yakun
• Wu Weiqiang
• Liao Xiangping
• Yang Huayong

Classifications

• F15B2211/20561

  reversible · CPC title

• F15B2211/3051

  Cross-check valves · CPC title

• F15B2211/6309

  the pressure being a pressure source supply pressure · CPC title

• B66C13/22 Primary

  for electric drives (transmitting control pulses B66C13/40; systems or devices of general application H02P) · CPC title

• B66C23/52

  Floating cranes (floating dredgers E02F) · CPC title