JP2021042018A - Boom operation system - Google Patents

Abstract

To provide a boom operation system capable of presenting a reaction force to an operation lever on the basis of an actually operated force.SOLUTION: A boom operation system S comprises: operation levers 51-54 that are tilted by an operation force; a boom 14 that is driven at a speed corresponding to the tilting angle of each of the operation levers 51-54; a force detector 55 that detects a force applied to a tip of the boom 14; a force controller 40c that calculates an angle or mechanical impedance on the basis of the force detected by the force detector 55; an angle/torque controller 40d that calculates an angle or torque on the basis of the calculated angle or mechanical impedance; and reaction force presentation devices 71-74 that present the calculated angle or torque to the operation levers 51-54.SELECTED DRAWING: Figure 1

Description

The present invention relates to a boom operating system mounted on a mobile crane or the like.

Conventionally, a mobile crane mainly includes a vehicle body having a traveling function, a swivel base mounted on the vehicle body so as to be able to turn horizontally, and a boom mounted on the swivel base so as to be undulating. Each of these components is configured to be driven by a hydraulic actuator. The torque and speed generated by the hydraulic actuator are controlled and adjusted by the operator operating the operating lever.

However, it is not easy to control the hydraulic actuator by the operating lever, and the operability is affected by the undulation angle of the boom, the weight of the suspended load, the position, and the like. Furthermore, in recent years, the so-called by-wire method, in which the hydraulic pressure does not return to the operating lever, is often adopted, and the operation is becoming more difficult.

Therefore, for example, Patent Document 1 discloses a force sense presentation operating lever device in which a reaction force against tilting of the operating lever is generated by electromagnetic means and a part of the reaction force is generated by friction braking means. With this configuration, the operator can feel the reaction force of the operating lever.

Japanese Unexamined Patent Publication No. 2011-28601

However, the conventional technique including the force sense presentation operation lever device of Patent Document 1 does not consider the weight of the suspended load and the operating force of the machine itself. Therefore, the operator could not sense the difference in the weight of the suspended load and the operating condition of the machine.

Therefore, it is an object of the boom operating system of the present invention to provide a boom operating system capable of presenting a reaction force to an operating lever based on an actually acting force.

In order to achieve the above object, the boom operating system of the present invention is a force for calculating an angle or mechanical impedance based on an operating lever, a boom, a force detector, and a force detected by the force detector. The controller, the angle / torque controller that calculates the angle or torque based on the calculated angle or mechanical impedance, and the counter that presents the calculated angle or torque to the operating lever in addition to the operating force. It is equipped with a force presenter.

As described above, the boom operation system of the present invention includes an operation lever, a boom, a force detector, a force controller, an angle / torque controller, and a reaction force presenter. A reaction force can be presented to the operating lever based on the force actually acting on the tip of the. Therefore, operations such as fine adjustment of the position of the suspended load and steady rest can be easily performed.

It is a side view of a mobile crane. It is a block diagram of a boom operation system. It is a block diagram of a boom operation system. It is explanatory drawing of the operation lever. (A) is an explanatory view of a cross lever used for undulating operation and turning operation, and (b) is an explanatory view of a uniaxial lever used for vertical operation. It is an operation diagram about the work in the position which is hard to see.

Hereinafter, examples according to the present invention will be described with reference to the drawings. However, the components described in the following examples are examples, and the technical scope of the present invention is not limited to them.

Examples of the mobile crane provided with the boom operation system (S) of this embodiment include a rough terrain crane, an all terrain crane, and a truck crane. Hereinafter, the rough terrain crane will be described as an example, but the boom operation system (S) according to the present invention can also be applied to other mobile cranes. In addition, the present invention can be applied to aerial work platforms equipped with a boom.

(Structure of mobile crane)
First, the configuration of the mechanical system of the mobile crane will be described with reference to the side view of FIG. As shown in FIG. 1, the rough terrain crane 1 of the present embodiment has a vehicle body 10 which is a main body portion of a vehicle having a traveling function, outriggers 11 provided at four corners of the vehicle body 10, ... It includes a swivel table 12 mounted so as to be able to swivel horizontally, and a boom 14 mounted on the rear portion of the swivel table 12.

The outrigger 11 can slide out / slide outward from the vehicle body 10 in the width direction by expanding / contracting the slide cylinder, and can extend / jack retract in the vertical direction from the vehicle body 10 by expanding / contracting the jack cylinder. Is.

The swivel base 12 has a pinion gear to which the power of the swivel motor 61 is transmitted, and the pinion gear meshes with a circular gear provided on the vehicle body 10 to rotate around a swivel shaft. The swivel base 12 further includes a cockpit 18 arranged on the right front side and a counterweight 19 arranged on the rear side.

Further, a winch 13 for hoisting / lowering the wire 16 is arranged at the rear portion of the swivel base 12. By rotating the winch motor 64 in the forward direction / the reverse direction, the winch 13 rotates in two directions, a winding direction (winding direction) and a winding direction (feeding direction).

The boom 14 is nested by a base end boom 141, an intermediate boom 142 (s) and a tip boom 143, and can be expanded and contracted by a telescopic cylinder 63 arranged inside. A sheave is arranged on the state-of-the-art boom head 144 of the tip boom 143, and a wire 16 is hung around the sheave to hang a hook 17.

The base portion of the base end boom 141 is rotatably attached to a support shaft installed at the rear portion of the swivel base 12, and can be undulated up and down with the support shaft as the center of rotation. An undulating cylinder 62 is bridged between the swivel base 12 and the lower surface of the base end boom 141, and the entire boom 14 can be undulated by expanding and contracting the undulating cylinder 62. ..

(Control system configuration)
Next, the configuration of the control system of the boom operation system S of this embodiment will be described with reference to the block diagram of FIG. The boom operation system S is configured around a controller 40 as a control unit. The controller 40 can be a general-purpose microcomputer having an input port, an output port, an arithmetic unit, and the like.

The controller 40 receives an operation signal from the operation levers 51 to 54 (swivel / undulation lever 51, telescopic lever 53, hoisting / hoisting lever 54), and receives actuators 61 to 64 (swivel motor) via a control valve (not shown). 61, undulating cylinder 62, telescopic cylinder 63, winch motor 64).

As shown in FIG. 4A, the swivel / undulation lever 51 is a cross lever that tilts around two orthogonal axes, and one lever can control two movements (swivel and undulation). .. That is, by tilting the turning / undulating lever 51 to the left, the boom 14 turns to the left, and by tilting to the right, the boom 14 turns to the right. Further, the boom 14 is tilted by tilting the swivel / undulation lever 51 to the back, and the boom 14 is raised by tilting it toward the front.

Then, in the swivel / undulation lever 51 of this embodiment, angle detectors 41 and 42 are installed for each of the swivel and undulation rotation axes in order to detect the angle at which the lever itself is tilted. The turning angle detector 41 is, for example, a potentiometer, which detects a left-right tilt angle and transmits it to the controller 40. Similarly, the undulation angle detector 42 detects the back-front tilt angle and transmits it to the controller 40.

Then, in order to present a reaction force to the swivel / undulation lever 51 according to the force actually acting on the tip of the boom 14, the swivel / undulation lever 51 has a reaction force presenter for each rotation axis of the swivel and undulation. 71 and 72 are installed. The turning reaction force presenter 71 is, for example, an electric motor, and presents the reaction force acting in the turning direction to the turning / undulating lever 51, and the undulating reaction force presenter 72 swivels the reaction force in the undulating direction. / Present to the undulation lever 51.

Next, although not shown, the telescopic lever 53 is a lever that tilts around one axis so that the telescopic operation can be controlled. Further, in the telescopic lever 53 of this embodiment, an angle detector 43 is installed on the rotation axis of the telescopic lever 53 in order to detect the angle at which the lever itself is tilted. The expansion / contraction angle detector 43 detects the back-front tilt angle and transmits it to the controller 40.

Further, in the telescopic lever 53 of the present embodiment, a reaction force presenter 73 is installed on the rotation shaft of the telescopic lever 53 in order to present a reaction force to the telescopic lever 53 according to a force actually acting on the tip of the boom 14. ing. The expansion / contraction reaction force presenter 73 presents the reaction force acting in the expansion / contraction direction to the expansion / contraction lever 53. Here, the case where the angle detector 43 and the reaction force presenter 73 are installed on the telescopic lever 53 has been described, but the present invention is not limited to this, and the movement of the suspended load due to the telescopic operation is restricted. Etc., the angle detector 43 and the reaction force presenter 73 may not be installed on the telescopic lever 53.

Next, as shown in FIG. 4B, the hoisting / unwinding lever 54 is a lever that tilts about one axis, and can control the hoisting operation or the unwinding operation. That is, the winch 13 is wound up by tilting the hoisting / lowering lever 54 toward you, and the winch 13 is hoisted by tilting it toward the back.

The hoisting / hoisting lever 54 of this embodiment is provided with an angle detector 44 on its rotation axis in order to detect the angle at which the lever itself is tilted. The hoisting / hoisting angle detector 43 is, for example, a potentiometer, which detects a back-front tilt angle and transmits it to the controller 40.

Further, in order to present a reaction force to the hoisting / unwinding lever 54 according to the force actually acting on the tip of the boom 14, the hoisting / unwinding lever 54 of the present embodiment has its rotation axis. A reaction force presenter 74 is installed. The hoisting / unwinding reaction force presenter 74 is, for example, an electric motor, and presents a reaction force acting in the vertical direction to the hoisting / unwinding lever 54.

In addition, the weight of the suspended load acts downward on the hoisting / unwinding lever 54, but when no operating force is applied to the lever or when a weak operating force is applied, the reaction force presentation is insensitive. It is controlled to keep it inside. That is, in general, various operating levers are provided with a dead zone in which the actuator does not operate even when the actuator is moved (tilted) by applying an operating force, and the hoisting / lowering lever 54 is maintained in this range. It has become like. By being controlled in this way, it is possible to prevent the lever from moving significantly when the lever is not operated or when the lever is released, and as a result, the boom 14 and the wire 16 do not operate unexpectedly.

Further, the hoisting / lowering lever 54 may be provided with irregularities on the sliding portion in order to give a notch feeling to the original neutral position. In this way, the reason why the original neutral position is notched is that the hoisting / lowering lever 54 is offset by the action of gravity, so that the operator cannot determine the neutral position through the feeling of the hand. This is to prevent it.

Next, the force detector 55 is installed on the boom head 144 of the boom 14, and is for detecting the force acting on the boom head 144 (boom tip reaction force). The force detector 55 includes a load cell that directly detects force by measuring tension, a position measuring device (for example, GPS) that measures position and acceleration and indirectly detects force by time derivative, and acceleration measurement. The device can be used. The detected boom tip reaction force is transmitted to the controller 40.

The controller 40 is a control unit that controls the operation of the boom 14 and the winch 13, and its functional units include a speed converter 40a, a speed controller 40b, a force controller 40c, and an angle / torque controller 40d. And have. Hereinafter, the functions of each functional unit will be described. The functions of the following functional units are performed for each actuator 61 to 64 corresponding to the operation levers 51 to 54.

The speed converter 40a receives the lever voltage from the angle detectors 41 to 44, converts it into a speed command value, and then transmits it to the speed controller 40b. The speed of this actuator is controlled by feedback control.

The speed controller 40b controls the speed of the actuator based on an error (deviation) between the speed command value from the speed converter 40a and the fed-back measured value (feedback control). Specifically, a predetermined current is applied to the control valve corresponding to each actuator based on the error (deviation).

The force controller 40c calculates an angle command or a mechanical impedance command based on the force (boom tip reaction force) detected by the force detector 55. Then, the force controller 40c of the present embodiment is adapted to calculate an angle command or a mechanical impedance command based on the reaction force presentation control based on the force control or the reaction force presentation control based on the impedance control. ..

When calculating the mechanical impedance command by the reaction force presentation control based on the force control, the mechanical impedance command can be calculated as follows, for example.

そして、レバーに与えるべき仮想インピーダンスとして、任意の仮想粘性係数Ｄｍ、仮想ばね係数Ｋｍを用いると、レバーに与えるべき力Ｆｍは下式を用いて決定できる。

When the boom tip reaction force F, the virtual mass Mb, the virtual viscosity coefficient Db, and the virtual spring constant Kb are used as the virtual impedance of the boom tip arbitrarily determined, the virtual motion ddx of the boom tip is used when some of the latest sampling data are used. , Dx, x can be obtained by the following equation.

Then, when an arbitrary virtual viscosity coefficient Dm and virtual spring constant Km are used as the virtual impedance to be applied to the lever, the force Fm to be applied to the lever can be determined by using the following equation.

When calculating the angle command by the reaction force presentation control based on the impedance control, the angle command can be calculated as follows, for example.

Similar to the force control-based reaction force presentation control, equation 1 is used to obtain dx. When P control is performed on the lever using the difference from the target speed command value dxm indicated by the position of the lever and an arbitrary R is used, the force Fm to be applied to the lever can be determined by using the following equation.

The angle / torque controller 40d calculates the angle or torque based on the angle command calculated by the force controller 40c or the mechanical impedance command, and instructs the reaction force presenters 71 to 74. In this way, the so-called bilateral control is realized by presenting the force sense to the operating levers 51 to 54 via the reaction force presenters 71 to 74.

Then, the angle / torque controller 40d of this embodiment adds the calculated angle or mechanical impedance, calculates the angle or torque based on the operating limit angle or the operating limit mechanical impedance, and presents the reaction force. It is designed to instruct the vessels 71 to 74. These operating limit angles or operating limit mechanical impedances are calculated based on the stability limit, the output limit of each actuator, and the like.

(Block diagram of impedance control)
Next, the input / output relationship of each element in impedance control will be described with reference to the block diagram of FIG. First, the boom tip reaction force is measured by the force detector 55 and transmitted to the force controller 40c of the controller 40. The force controller 40c calculates an angle command or a mechanical impedance command based on the received boom tip reaction force, and transmits the angle command or the mechanical impedance command to the comparison unit (white circle in the figure) immediately before the angle / torque controller 40d. Here, the force controller 40c calculates an angle or mechanical impedance based on the above-mentioned force control-based reaction force presentation control or impedance control-based reaction force presentation control.

The comparison unit compares the received angle command or mechanical impedance command with the operating limit angle or operating limit mechanical impedance, and transmits the received angle command or mechanical impedance command to the angle / torque controller 40d within a range that does not exceed the operating limit angle or operating limit mechanical impedance. .. Next, the angle / torque controller 40d calculates an angle or torque command based on the received angle command or mechanical impedance command, and transmits the angle / torque command to the reaction force presenters 71 to 74.

The reaction force presenters 71 to 74 transmit the presented reaction force to the comparison unit based on the received angle or torque command, add it to the operating force, and then transmit it to the angle detectors 41 to 44. Therefore, the operator can feel the reaction force due to the suspended load through the operation levers 51 to 54 in addition to the normal operation feeling of the operation levers 51 to 54 (the presented reaction force does not act).

The angle detectors 41 to 44 detect the angle at which the operating levers 51 to 54 are tilted, convert it into a lever voltage, and then transmit it to the speed converter 40a. The speed converter 40a transmits a speed command value to the comparison unit, compares it with the actual operating speed of the actuator, and transmits an error (deviation) to the speed controller 40b. Finally, the speed controller 40b controls the speed of the actuator based on the error (deviation) (feedback control).

(effect)
Next, the effects of the boom operation system S of this embodiment will be listed and described.

(1) As described above, in the boom operation system S of the present embodiment, the operation levers 51 to 54 tilted by the operation force and the boom driven at a speed corresponding to the tilt angle of the operation levers 51 to 54. 14 and a force detector 55 that detects the force acting on the tip of the boom 14, and a force controller 40c that calculates an angle or mechanical impedance based on the force detected by the force detector 55. An angle / torque controller 40d that calculates an angle or torque based on an angle or mechanical impedance and instructs the reaction force presenter, and an operating lever 51 to 54 that adds the specified angle or torque to the operating force. The reaction force presenters 71 to 74 presented to the above are provided. According to such a configuration, a reaction force (force sense) can be presented to the operating levers 51 to 54 based on the force actually acting on the tip of the boom 14. Therefore, operations such as fine adjustment of the position of the suspended load and steady rest can be easily performed.

In this way, by giving the operator the feeling of directly grasping the tip of the boom with his / her own hand, it becomes easier to grasp the behavior of the suspended load, the steady rest operation becomes easier, and only the visual sense You will be able to grasp the status of suspended loads without relying on them.

For example, the present invention is effective in a dangerous situation at a position where it is difficult to see visually (for example, above a building) as shown in FIGS. 5A and 5B. As shown in FIG. 5A, in the ground cutting and unloading operations, the operator can grasp the situation by the change in the force sense in the vertical direction. Further, as shown in FIG. 5B, in the prohibited horizontal pulling operation, the operator can grasp the horizontal pulling situation by changing the lever load in the horizontal direction.

In addition, it is generally known that it is a good idea to chase the suspended load in order to stop the load swing with a crane or the like. However, according to the present invention, the operation is performed in the direction in which the tension due to the suspended load acts. By making it easier to tilt the levers 51 to 54, the chasing operation becomes easier, and as a result, it becomes easier to prevent the load swing.

(2) Further, the angle / torque controller 40d is added to the calculated angle or mechanical impedance to calculate the angle or torque based on the operating limit angle or the operating limit mechanical impedance, and is a reaction force presenter. Since the instructions are given to 71 to 74, the reaction force presenters 71 to 74 can be operated while considering the stability limit, the output limit of each actuator, and the like.

Further, since the force controller 40c is designed to calculate the angle or the mechanical impedance based on the reaction force presentation control based on the force control or the reaction force presentation control based on the impedance control, the mass M and the damper Optimal impedance control can be executed according to the combination of the values of D and the spring K.

(3) Of the operating levers 51 to 54, the operating lever (winding / winding lever) 54 used for vertical operation is presented with a vertical downward force by the reaction force presenter 74. The position of the operating lever 54 is set to remain within the dead zone when the operating force is equal to or less than a predetermined value, and as a result, the operating lever 54 moves significantly when not operated or when the operating lever 54 is released. , The boom 14 and the wire 16 can be prevented from performing unintended operations.

(4) Further, among the operation levers 51 to 54, the operation lever (winding / winding lever) 54 used for vertical operation is formed so as to give a notch feeling for determining the neutral point. As a result, it is possible to prevent the operator from being unable to determine the neutral point due to the offset due to gravity.

Although the embodiments of the present invention have been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and design changes to the extent that the gist of the present invention is not deviated are described in the present invention. included.

For example, in the present embodiment, the swivel / undulation lever 51 has been described as a cross lever, but the present invention is not limited to this, and two uniaxial levers may be used.

S: Operation system;
1: Rough terrain crane;
10: Body; 12: Swivel; 13: Winch;
14: Boom; 16: Wire; 17: Hook;
40: Controller; 40a: Speed Converter; 40b: Speed Controller;
40c: Force controller; 40d: Angle or torque controller;
41-44: Angle detector;
51: Swivel / undulation lever; 53: Telescopic lever; 54: Hoisting / hoisting lever;
55: Force detector;
61: Swing motor; 62: Undulating cylinder;
63: Telescopic cylinder; 64: Winch motor;
71-74: Reaction force presenter

Claims (4)

The operation lever that is tilted by the operation force and
A boom driven at a speed corresponding to the tilt angle of the operating lever,
A force detector that detects the force acting on the tip of the boom,
A force controller that calculates an angle or mechanical impedance based on the force detected by the force detector,
An angle / torque controller that calculates an angle or torque based on the calculated angle or mechanical impedance,
A boom operating system comprising a reaction force presenter that adds a calculated angle or torque to the operating force and presents it to the operating lever. The angle / torque controller calculates the angle or torque based on the operation limit angle or the operation limit mechanical impedance by adding it to the calculated angle or the mechanical impedance, and instructs the reaction force presenter. The boom operating system according to claim 1. Among the operating levers, the operating lever used for vertical operation is presented with a vertical downward force by the reaction force presenter, and the position of the operating lever is in a state where the operating force is equal to or less than a predetermined value. The boom operating system according to claim 1 or 2, wherein the boom operation system is designed to remain within the dead zone. The operating lever according to any one of claims 1 to 3, wherein the operating lever used for vertical operation is formed so as to give a notch feeling for determining the neutral point. Boom operation system.

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