CN111055913A - Crane getting-on operation control steering device and method - Google Patents
Crane getting-on operation control steering device and method Download PDFInfo
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- CN111055913A CN111055913A CN201911199484.6A CN201911199484A CN111055913A CN 111055913 A CN111055913 A CN 111055913A CN 201911199484 A CN201911199484 A CN 201911199484A CN 111055913 A CN111055913 A CN 111055913A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D5/00—Power-assisted or power-driven steering
- B62D5/04—Power-assisted or power-driven steering electrical, e.g. using an electric servo-motor connected to, or forming part of, the steering gear
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- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
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- Steering Control In Accordance With Driving Conditions (AREA)
Abstract
The invention discloses a crane getting-on control steering device and method, which are used for determining a target steering angular speed of a steering axle by a control unit according to an inclination angle of a control unit on the premise of effective getting-on control steering. The target steering direction of the vehicle steering axle is consistent with the inclination direction of the control unit, the larger the inclination angle of the control unit is, the larger the target steering angular velocity of the steering axle is, and when the steering axle rotates to the maximum angle, the steering angular velocity is reduced to 0 no matter the inclination angle of the control unit, and if the control unit returns to the middle position, the steering axle is kept at the current position.
Description
Technical Field
The invention relates to the technical field of crane design, in particular to a crane getting-on operation steering device and a crane getting-on operation steering method.
Background
The related description of the terms involved in the present invention is as follows:
a crane: a multi-action hoisting machine, also called a crane, for vertically lifting and horizontally carrying heavy objects within a certain range;
getting on the bus operating room: the lifting device has the functions of lifting objects up and down, left and right, front and back and the like, and is internally provided with an operating space of an operating unit, a display, an accelerator, a seat and the like;
getting on the vehicle to control and run: a crane driving working condition is provided, under which the crane can control the vehicle to drive in an upper vehicle control chamber without returning to a lower vehicle control chamber for operation;
electronic power steering mechanism: the device comprises a mechanical part of an electric steering gear, a motor and a sensor, and is a device for providing power assistance for a driver to operate a steering system through the motor;
a turntable locking pin: a mechanical bolt capable of fixing or separating a swing mechanism and a frame is disclosed, a rotary table locking pin can be locked only when an arm support is right in front of or right behind, and the arm support cannot be swung when the locking pin is in a locking state;
a steering axle: the direction of travel of the vehicle is controlled at the discretion of the driver, the steering wheels (typically the front axle) of the vehicle being angled relative to the longitudinal axis of the vehicle.
A control unit: the vehicle logic and information processing unit is used for converting the acquired system parameters; receiving various control instruction conversion signals of an operator, such as an accelerator instruction; under the management of control software, various control functions are completed, and real-time communication is carried out with the monitoring system.
A manipulation unit: means for controlling the motion of the vehicle, such as handles, knobs, etc.
The crane steering system is used for changing or recovering the traveling direction of the crane and is an important system in the traveling process of the crane. The crane is controlled to run without disassembling the suspension arm and the balance weight, so that the crane is suitable for scenes with narrow operation space and frequent switching between suspension weight and transition, and the transition efficiency and the operation convenience of the crane can be effectively improved. The crane operator can switch the running control mode, can control in the control room after entering the getting-on control running mode, and does not need to enter the cab for running operation.
In the prior art, the getting-on vehicle controls the steering of the vehicle through the control unit in the control room. The control unit turns left, and the vehicle turns left; the control unit turns to the right, and the vehicle turns to the right; when the control unit returns to the neutral position, the steering axle returns to the neutral position, and the steering angle of the steering axle corresponds to the inclination angle of the control unit. And when getting on the bus, the steering control angular velocity is a fixed value, and the calibration is needed according to the vehicle rotation angle range and the steering following time requirement.
The defects of the prior scheme are as follows:
1) in the existing scheme, the inclination angle of the control unit corresponds to the steering angle of the steering axle, and when no person operates the control unit, the control unit automatically returns to the middle position, so that the steering axle cannot be stopped at any angle position;
2) in the existing scheme, when a vehicle steers, in order to reduce tire shake in the steering process, the resolution (the resolution is generally more than 3 degrees) of a target steering angle (the target steering angle refers to an angle value sent to an electric control power-assisted steering controller after being processed by a control unit) of a steering wheel is set to be larger, so that a steering axle cannot steer according to any angle, and operation experience is influenced;
3) the vehicle steering power-assisted angular speed in the existing scheme is a fixed value, cannot be automatically adjusted, and is difficult to realize the micro-motion or quick function of axle steering.
Disclosure of Invention
The invention aims to overcome the defects in the prior art, provides a crane getting-on operation control steering method, and solves the technical problem that a steering control scheme in the prior art cannot stop at any angle position.
In order to solve the technical problem, the invention provides a crane getting-on operation control steering device which is characterized by comprising a control unit, an electric control power-assisted steering mechanism, an electric control power-assisted steering control unit, a steering angle sensor and an operation control unit;
the output end of the control unit is connected with the control unit, the control unit is connected with the electric control assistant steering control unit, the electric control assistant steering control unit is connected with the steering axle through an electric control power-assisted mechanism, and the output end of the angle sensor is connected with the electric control assistant steering control unit;
the control unit is used for receiving the input of the steering angle and the steering angular velocity of a user and transmitting the input information to the control unit;
the control unit is used for receiving the steering angle and the steering angular speed transmitted by the control unit and transmitting a steering angle signal and an angular speed signal to the electric control power-assisted steering control unit;
the electric control power-assisted steering control unit is used for receiving the steering angle and the steering angular speed information output by the control unit to control the electric control power-assisted steering mechanism and transmitting a steering axle angle signal acquired by the angle sensor to the control unit;
the electric control power-assisted steering mechanism is used for providing power-assisted steering to push the steering axle to rotate according to a steering angle and an angular speed;
and the angle sensor is used for detecting the angle of the steering axle and transmitting the angle to the electric control power-assisted steering control unit.
Furthermore, the device also comprises a boarding control running key, and the output end of the boarding control running key is connected with the control unit.
Correspondingly, the invention also provides a crane getting-on operation steering method which is characterized by comprising the following processes:
on the premise that the steering mode is effective in the getting-on control running mode, the control unit determines the target steering angular speed of the steering axle according to the inclination angle of the control unit; the target steering direction of the vehicle steering axle is consistent with the inclination direction of the control unit, and the larger the inclination angle of the control unit is, the larger the target steering angular speed of the steering axle is.
Further, the steering mode includes an getting-on manipulation running mode and a getting-off manipulation form mode.
Further, the control unit judges whether the fact that an operator presses an getting-on operation running key is received, whether the current vehicle is in a static state or not is judged, the electric control power-assisted steering system has no fault, and whether the turntable locking pin is in a locking state or not is judged, and if the four conditions are met simultaneously, the getting-on operation running mode is judged to be effective; and if at least one of the four conditions is not met, judging that the get-off control running mode is effective.
Furthermore, the control unit does not respond to the action of the operation unit within the range of +/-N degrees of the center in the control unit, and the steering axle is kept at the current position.
Further, when the steering axle reaches the deceleration limit angle M, the speed of the steering angular speed is limited, and the steering axle is protected from reaching the axle limit angle X at a smaller angular speed; and if the steering angular speed is smaller than the deceleration limit angle M, the speed of the steering angular speed is not limited.
Further, the steering angle of the steering axle reaches a limit angle X, and the steering angular speed is limited to 0.
Compared with the prior art, the invention has the following beneficial effects: according to the invention, on the premise that the control steering of the upper vehicle is effective, the control unit determines the target steering angular speed of the steering axle according to the inclination angle of the control unit. The target steering direction of the vehicle steering axle is consistent with the inclination direction of the control unit, the larger the inclination angle of the control unit is, the larger the target steering angular velocity of the steering axle is, and when the steering axle rotates to the maximum angle, the steering angular velocity is reduced to 0 no matter the inclination angle of the control unit, and if the control unit returns to the middle position, the steering axle is kept at the current position.
Drawings
FIG. 1 is a schematic diagram of the structure of the apparatus of the present invention;
FIG. 2 is a schematic view of a steering mode switching scheme;
FIG. 3 is a get-on steer vehicle steering scheme.
Detailed Description
The invention is further described below with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.
The purpose of the invention is:
(1) when the control of getting on the bus is selected, the operator controls the steering of the bus by operating the control unit; when the getting-on control is not selected to drive, the getting-on does not participate in the steering control of the vehicle, and the getting-off operation is completely carried out, so that the driving risk caused by the fact that a plurality of operation sources control a steering system at the same time or automatically switch the operation sources is avoided.
(2) An operator controls the steering angular speed of the steering axle by changing the opening size of the control unit, so that the fast turning and slow turning functions of the vehicle during turning are realized; the steering direction of the steering axle is consistent with the inclination direction of the control unit; when the control unit returns to the neutral position, the vehicle turns to a stop, and the steering axle is kept at the current position.
The system hardware mainly comprises a control unit, an electric control power-assisted steering mechanism, an electric control power-assisted steering control unit, an angle sensor and a control unit, wherein the output end of the control unit is connected with the control unit, the control unit is connected with the electric control assistant steering control unit, the electric control power-assisted steering control unit is connected with a steering axle through the electric control assistant steering mechanism, and the output end of the angle sensor is connected with the electric control power-assisted steering control unit.
The functions of the components are described as follows:
1) the control unit is used for receiving the input of the steering angle and the steering angular velocity of a user and transmitting the input information to the control unit; the control unit has the function of automatically returning to the middle position, namely when a user looses the control unit, the control unit returns to the middle position;
2) the control unit is used for receiving the steering angle and the steering angular speed transmitted by the control unit and transmitting a steering angle signal and an angular speed signal to the electric control power-assisted steering control unit;
3) the electric control power-assisted steering control unit is used for receiving the steering angle and the steering angular speed information output by the control unit to control the electric control power-assisted steering mechanism and transmitting a steering axle angle signal acquired by the angle sensor to the control unit;
4) the electric control power-assisted steering mechanism is used for providing power-assisted steering to push the steering axle to rotate according to a steering angle and an angular speed;
5) and the angle sensor is used for detecting the angle of the steering axle and transmitting the angle to the electric control power-assisted steering control unit.
The electric control power-assisted steering mechanism provided by the invention can be realized by a hydraulic control power-assisted steering device, and the angular speed of a steering axle is controlled by changing the steering power of the hydraulic control device.
The angle sensor is used for detecting the angle of the steering axle within the range of +/-72.5 degrees;
the crane steering mode comprises two modes: when the getting-on control running mode is selected, an operator controls the control unit to realize the steering of the getting-on control vehicle; when the get-off control running mode is selected, the getting-on does not participate in the steering control of the vehicle, and the get-off operation is completely carried out, so that the driving risks caused by the fact that a plurality of operation sources control the steering system simultaneously or the operation sources are automatically switched can be avoided in two different modes, and the safety of the product running operation is improved.
When the crane is just powered on, the default steering mode is in the lower vehicle control mode, and then the switching judgment of the steering mode is carried out according to the actual state and the requirement.
In order to realize the conversion of the steering modes, the invention is realized by arranging an upper vehicle control running key, wherein the output end of the upper vehicle control running key is connected with the control unit, the upper vehicle control running key is pressed to indicate that the upper vehicle control running mode is required to be switched, and when the upper vehicle control steering mode is used, the upper vehicle control running key is pressed again to indicate that the lower vehicle control running mode is required to be switched. The getting-on control running key can be realized by adopting a manual switch button in the prior art, and can also be realized by a touch button on a display screen.
The specific process of the steering mode switching is shown in fig. 2, the control unit judges whether an operator presses an upper vehicle control running key (namely, the judgment of switching to the upper vehicle control running mode in fig. 2) is received, whether the current vehicle is in a static state (namely, the judgment that the vehicle speed is less than a limit value V in fig. 2 is used for judging whether the vehicle is in the static state or not) is judged, the electric power steering system has no fault (namely, the electric power steering device in fig. 2 has no fault judgment, and factors influencing the electric power steering action are faults, such as motor undervoltage, thermal protection, angle sensor fault and the like), and whether the turntable locking pin is in a locking state, if the four conditions are met simultaneously, the upper vehicle control running mode is judged to be effective; and if at least one of the four conditions is not met, judging that the get-off control running mode is effective.
On the premise that the getting-on control running mode is effective, the method for controlling steering comprises the following processes:
the control unit determines the target steering angular speed of the steering axle according to the inclination angle of the control unit. The target steering direction of the vehicle steering axle is consistent with the inclination direction of the control unit, the larger the inclination angle of the control unit is, the larger the target steering angular velocity of the steering axle is, when the steering axle rotates to the maximum angle, the steering angular velocity is reduced to 0 no matter the inclination angle of the control unit, and if the control unit returns to the middle position, the steering axle is kept at the current position, and the control unit determines the target steering state of the steering axle according to the position information of the current control unit.
In a specific process, referring to fig. 3, the control unit judges through the inclination angle of the control unit, and if the control unit inclines to the left, the steering axle is controlled to turn to the left until the left maximum steering angle is reached; if the control unit inclines to the right, the steering axle is controlled to turn to the right until the steering angle on the right side is the maximum; if the control unit is positioned at the middle position +/-N degrees (the +/-N degrees are the middle dead zone of the control unit), namely the leftward or rightward inclination angle is smaller than N and is within the dead zone range,The control unit is considered to be in the middle position in the angle range), the control unit does not respond to the action of the operation unit, and the steering axle is kept at the current position.
The inclination angle of the control unit is in direct proportion to the steering angular velocity of the steering axle, and the steering angular velocity is linearly corresponding to the inclination angle of the control unit and can also be used as a curve corresponding to the inclination angle, namely when the control unit reaches the maximum inclination angle P, the steering angular velocity of the steering axle is the maximum set value L of the steering angular velocity. The steering angular speed is related to the current corner of the steering axle, when the steering axle reaches a deceleration limit angle M, the speed of the steering angular speed is limited, and the steering axle is protected from reaching an axle limit angle X at a smaller angular speed; and if the steering angular speed is smaller than the deceleration limit angle M, the speed of the steering angular speed is not limited. The steering angle of the steering axle reaches a limit angle X (the maximum steering angle of the steering axle), and the steering angular speed is limited to 0.
As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.
Claims (8)
1. A crane getting-on operation control steering device is characterized by comprising a control unit, an electric control power-assisted steering mechanism, an electric control power-assisted steering control unit, a steering angle sensor and an operation control unit;
the output end of the control unit is connected with the control unit, the control unit is connected with the electric control assistant steering control unit, the electric control assistant steering control unit is connected with the steering axle through an electric control power-assisted mechanism, and the output end of the angle sensor is connected with the electric control assistant steering control unit;
the control unit is used for receiving the input of the steering angle and the steering angular velocity of a user and transmitting the input information to the control unit;
the control unit is used for receiving the steering angle and the steering angular speed transmitted by the control unit and transmitting a steering angle signal and an angular speed signal to the electric control power-assisted steering control unit;
the electric control power-assisted steering control unit is used for receiving the steering angle and the steering angular speed information output by the control unit to control the electric control power-assisted steering mechanism and transmitting a steering axle angle signal acquired by the angle sensor to the control unit;
the electric control power-assisted steering mechanism is used for providing power-assisted steering to push the steering axle to rotate according to a steering angle and an angular speed;
and the angle sensor is used for detecting the angle of the steering axle and transmitting the angle to the electric control power-assisted steering control unit.
2. The crane getting-on operation steering device according to claim 1, further comprising a getting-on operation running key, wherein an output end of the getting-on operation running key is connected with the control unit.
3. A crane boarding control steering method according to any one of claims 1 to 2, characterized by comprising the following steps:
on the premise that the steering mode is effective in the getting-on control running mode, the control unit determines the target steering angular speed of the steering axle according to the inclination angle of the control unit; the target steering direction of the steering axle is consistent with the inclination direction of the control unit, and the larger the inclination angle of the control unit is, the larger the target steering angular speed of the steering axle is.
4. A crane boarding control steering method as claimed in claim 3, wherein the steering modes include a boarding control travel mode and a disembarking control form mode.
5. The crane getting-on operation steering method according to claim 3, wherein the control unit judges whether the fact that the operator presses the getting-on operation running key is received, whether the current vehicle is in a static state, the electric power steering system has no fault, and the turntable locking pin is in a locking state, and if the four conditions are met simultaneously, the getting-on operation running mode is determined to be effective; and if at least one of the four conditions is not met, judging that the get-off control running mode is effective.
6. The method as claimed in claim 3, wherein if the steering unit is within ± N ° of the neutral position, the control unit does not respond to the operation of the operation unit and the steering axle is maintained at the current position.
7. The crane getting-on operation steering method as claimed in claim 3, wherein when the steering axle reaches the deceleration limit angle M, the speed limitation of the steering angular velocity is started to protect the steering axle from reaching the axle limit angle X at a smaller angular velocity; and if the steering angular speed is smaller than the deceleration limit angle M, the speed of the steering angular speed is not limited.
8. The crane boarding control steering method according to claim 3, wherein the steering angle of the steering axle reaches a limit angle X, and the steering angular velocity is limited to 0.
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CN201911199484.6A CN111055913A (en) | 2019-11-29 | 2019-11-29 | Crane getting-on operation control steering device and method |
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CN201911199484.6A CN111055913A (en) | 2019-11-29 | 2019-11-29 | Crane getting-on operation control steering device and method |
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CN105984492A (en) * | 2015-03-16 | 2016-10-05 | 株式会社捷太格特 | Steering device |
CN109017979A (en) * | 2018-08-09 | 2018-12-18 | 北京智行者科技有限公司 | Rotating direction control method and system |
CN110435757A (en) * | 2019-08-29 | 2019-11-12 | 吉林大学 | A kind of automatically controlled steering system of steeraxle |
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2019
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Patent Citations (7)
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DE10302268A1 (en) * | 2003-01-22 | 2004-07-29 | Zf Lenksysteme Gmbh | Motor vehicle steer-by-wire steering system in which steering is controlled using feedback and a simulation system, with a driving direction prior to failure of the simulation system maintained in the event of its failure |
CN101596915A (en) * | 2009-07-10 | 2009-12-09 | 奇瑞汽车股份有限公司 | A kind of automobile steering system based on line traffic control |
CN101722983A (en) * | 2010-01-14 | 2010-06-09 | 南京航空航天大学 | Electric power-assisted steering system with variable transmission ratio and method for controlling transmission ratio thereof |
CN202671062U (en) * | 2012-06-18 | 2013-01-16 | 徐州重型机械有限公司 | Crane and wheel steering switching device thereof |
CN105984492A (en) * | 2015-03-16 | 2016-10-05 | 株式会社捷太格特 | Steering device |
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Application publication date: 20200424 |