CN102245491A - Motion control of work vehicle - Google Patents

Abstract

A method for controlling a boom assembly (20) includes providing a boom assembly having an end effector (38). The boom assembly includes an actuator (22, 34) in fluid communication with a flow control valve. A desired coordinate of the end effector of the boom assembly is converted from Cartesian space to actuator space. A deflection error of the end effector based on a measured displacement of the actuator is calculated. A resultant desired coordinate of the end effector is calculated based on the desired coordinate and the deflection error. A control signal for the flow control valve is generated based on the resultant desired coordinate and the measured displacement of the actuator. The control signal is shaped to reduce vibration of the boom assembly. The shaped control signal is transmitted to the flow control valve.

Description

The action control of working truck

The cross reference of related application

The application is the pct international patent application that proposes on October 16th, 2009, with the applicant of national corporation Eaton Corporation name as the All Countries of appointment except that the U.S., and, Chinese citizen QingHui Yuan, United States citizen Jae Y.Lew and Thailand citizen Damrongrit Piyabongkarn are only as the applicant who specifies the U.S..It is 61/105,952 U.S. Provisional Patent Application preceence that the application requires in the sequence number that on October 16th, 2008 proposed.

Background technology

Construction vehicle can be used for providing temporarily approaching to relative inaccessible area.A lot of such vehicles comprise the arm (boom) that possesses a plurality of joints (joint).Can come Control arm by the displacement in control joint.But such control depends on the skilled of operator.

When arm stretched, vibration became a problem.The conventional techniques that is used to reduce or eliminate vibration causes not the system in response to its operator electrically.

Summary of the invention

An example of the present disclosure relates to the method for Control arm assembly.Described method comprises providing to have the terminal arm component of implementing device (end effector).Arm component comprises the actuator that is communicated with the flow-controlling gate fluid.The expectation coordinate of the end of arm component being implemented device is transformed into the actuator space from cartesian space.Calculating is implemented the device offset error based on the end of actuator Displacement Measurement.Calculate the expectation coordinate that the terminal result who implements device obtains according to expectation coordinate and offset error.Generate the control signal of flow-controlling gate based on result expectation coordinate that obtains and the actuator displacement that measures.Control signal by shaping to reduce the vibration of arm component.Control signal after the shaping is sent to flow-controlling gate.

Another example of the present disclosure relates to working truck.Working truck comprises having the terminal arm component of implementing device.Actuator joins arm component to.Actuator is suitable for arm component is positioned.Actuator sensor is suitable for measuring the displacement of actuator.Flow-controlling gate is communicated with the actuator fluid.Controller is connected electrically to flow-controlling gate.Controller is applicable in response to incoming signal ground actuation flow control valve.Controller comprises action controlling schemes (scheme), and the action controlling schemes comprises coordinate transformation module, deflection compensated module, axle control module and input shaper module.The expectation coordinate that coordinate transformation module is implemented device with the end of arm component is transformed into the actuator space by cartesian space.Based on the result of a measurement from actuator sensor, the deflection compensated module is calculated the terminal offset error of implementing device.The axle control module generates control signal according to expectation coordinate, offset error and from the result of a measurement of actuator sensor.The input shaper module is carried out shaping to the control signal that is sent to flow-controlling gate, to reduce the vibration of arm component.

Another example of the present disclosure relates to the damping ratio of calibration arm assembly of use traffic control cock and the method for natural frequency.This method comprises from the pressure signal of pressure sensor reception about the pressure the actuator.For the period 1, record high pressure values and low pressure values and the moment that is associated with these force value.For second round, record high pressure values and low pressure values and the moment that is associated with these force value.According to calculating natural frequency and damping ratio for the force value in first and second cycles and the moment that is associated with force value.

Another example of the present disclosure relates to a kind of method that is used for control signal is carried out shaping for flexible structure (flexible structure).This method comprises according to expectation coordinate generation control signal.Use time-varying input shaping scheme that control signal is carried out shaping.Time-varying input shaping scheme receives the result of a measurement from sensor, infers the natural frequency and the damping ratio of flexible structure according to the result of a measurement of sensor, and according to result of a measurement and the natural frequency of being inferred and damping ratio control signal is carried out shaping.

Below introduction will provide multiple other example.These examples can relate to personal feature and combination of features.Will be seen that top general introduction and following specifying only are exemplary and indicative, and not to embodiment disclosed herein based on wide design limit.

Description of drawings

Fig. 1 is the lateral plan of working truck, and this working truck has the example feature according to the example of principle of the present disclosure;

Fig. 2 is the scheme drawing of control system that is used for the working truck of Fig. 1;

Fig. 3 is the scheme drawing of flow-controlling gate that is suitable for the control system of Fig. 2;

Fig. 4 is the scheme drawing by the action controlling schemes of the controller use of the control system of Fig. 2;

Fig. 5 is the scheme drawing of arm component deflection of the working truck of Fig. 1;

Fig. 6 is the scheme drawing of joint-actuator space conversion;

Fig. 7 is the scheme drawing that is used for determining the method for the damping ratio of arm component and natural frequency;

Fig. 8 is to use flow-controlling gate damping ratio and natural frequency to be carried out the scheme drawing of Calibration Method.

The specific embodiment

To describe the of the present invention exemplary example shown in the accompanying drawing now in detail.Running through accompanying drawing will use identical reference number to refer to same or analogous structure as far as possible.

Referring now to Fig. 1, show exemplary working truck, its integral body is denoted as 10.Working truck 10 comprises a plurality of joints of using linearity and/or revolving actuator (for example cylinder, electrical motor etc.) to be activated.These linearities and revolving actuator are applicable to stretching, extension or withdrawal arm component and the control setting job platform at the arm component end.

Working truck 10 comprises a plurality of flow-controlling gates and a plurality of sensor.Flow-controlling gate is by the electronic control unit controls of working truck 10.Electronic control unit receives the expectation input and receives the measurement input from described a plurality of sensors from the operator.By the usage operation controlling schemes, the electronic control unit output signal is to flow-controlling gate, workplatform is moved to the position of expectation.The action controlling schemes is suitable for reducing the vibration of arm component and the good response that maintenance is imported the operator.

Working truck 10 can be a kind of in the several work vehicle, for example hoisting crane, arm elevator, scissor lift etc., but for for the purpose of the convenience of explanation, working truck 10 will be described to the aerial work platform at this.Aerial work platform 10 is suitable for providing approaching to such zone: because height and/or position, it is difficult to by ground people approaching usually.

In the embodiment shown in fig. 1, aerial work platform 10 comprises the base 12 with a plurality of wheels 14.Aerial work platform 10 further comprises car body 16, and it rotatably is installed to base 12, so car body 16 can be with respect to base 12 rotations.The anglec of rotation of car body 16 is expressed as θ ₁First electrical motor 18 (as shown in Figure 2) makes car body 16 with respect to base 12 rotations.In an example of the present disclosure, first electrical motor 18 is coupled to gear reducer.

Flexible structure 20 is installed to car body 16 by swivel.For the purpose of the convenience that illustrates, flexible structure 20 is described as arm component 20 at this.Arm component 20 can move up and/or down.This angle of rotation θ that moves up and/or down by arm component 20 of arm component 20 ₂Expression.First cylinder 22 (as shown in Figure 2) is applicable to and promotes and reduction arm component 20.First end 24 (as shown in Figure 2) of first cylinder 22 is connected to arm component 20, and second end 26 (as shown in Figure 2) is connected to car body 16.

Arm component 20 comprises bottom arm 28, intermediate arm 30 and top arm 32.Bottom arm 29 is connected to the car body 16 of aerial work platform 10.Middle and top arm 30,32 is a telescopic boom, and it is protruding from bottom arm 28 vertically.As shown in Figure 1, middle and top arm 30,32 is in punctured position.The length l of arm component 20 ₃Can by in the middle of shrinking or stretching and top arm 30,32 change.The length l of arm component 20 ₃Change via second cylinder 34 and corresponding mechanical connection 36.

Job platform 38 is installed to the end of top arm 32.The degree of dip of job platform 38 (pitch) keeps parallel to the ground by the MS master-slave design of Hydraulic System, the yaw direction of job platform 38 (yaw orientation) θ ₅By 42 controls of second electrical motor.

Referring now to Fig. 2, show the rough schematic view of the control system 50 of aerial work platform 10.Control system 50 comprises fluid pump 52, fluid reservoir 54, a plurality of flow-controlling gate 56, a plurality of actuator 58 and controller 60.

In an example of the present disclosure, fluid pump 52 is load sensing pumps.Load sensing pump 52 is communicated with load-sensing valve 150 fluids.Load-sensing valve 150 is suitable for slave controller 60 received signals 152.In an example of the present disclosure, signal 152 is pulse-width signals.

Described a plurality of actuator 58 comprises first and second cylinders 22,34 and first and second electrical motors 18,42.Described a plurality of flow-controlling gate 56 is suitable for controlling described a plurality of actuator 58.By controlling described a plurality of actuator 58, job platform 38 aloft interior being directed to expectation of operation envelope of job platform 10 reaches desired locations.

In an example of the present disclosure, first flow control cock 56a is communicated with first cylinder, 22 fluids, the second flow-controlling gate 56b is communicated with second cylinder, 34 fluids, the 3rd flow-controlling gate 56c is communicated with first electrical motor, 18 fluids, and the 4th flow-controlling gate 56d is communicated with second electrical motor, 42 fluids.The valve that is suitable for use as each flow-controlling gate 56a-56d is described in No.GB2328524 of British patent and U.S. Patent No. 7,518,523, and its disclosed content whole is incorporated into herein as a reference.First control mouthful 66 and second control mouth 68 that each flow-controlling gate 56a-56d comprises the supply port 62 that is communicated with fluid pump 52 fluids, the vessel port 64 that is communicated with fluid reservoir 54 fluids and is communicated with one of described a plurality of actuators 58 fluid.

Control system 50 also comprises a plurality of fluid pressure sensors 70.In an example of the present disclosure, first pressure sensor 70a monitoring is from the fluid pressure of fluid pump 52, and the second pressure sensor 70b monitoring stream is toward the fluid pressure of fluid reservoir 54.The first and second pressure sensor 70a, 70b communicate by letter with controller 60.In an example of the present disclosure, the first and second pressure sensor 70a, 70b communicate by letter with controller 60 by load-sensing valve 150.

Each flow-controlling gate 56a-56d is communicated with the 3rd pressure sensor 70c and the 4th pressure sensor 70d fluid.The third and fourth pressure sensor 70c, 70d monitor the fluid pressure that flows to and come self-corresponding actuator 58 on the first and second control mouths 66,68 respectively.In an example of the present disclosure, the third and fourth pressure sensor 70c, 70d are integrated among the flow-controlling gate 56a-56d.

Control system 50 also comprises a plurality of actuator sensor 72, and it monitors the axial or position of rotation of described a plurality of actuator 58.Described a plurality of actuator sensor 72 is suitable for to the signal of controller 60 transmissions about the displacement (for example position) of described a plurality of actuators 58.

In the embodiment shown in Figure 2, the first and second actuator sensor 72a, 72b monitor the displacement of first and second cylinders 22,34.In an example of the present disclosure, the first and second actuator sensor 72a, 72b are laser sensor.The third and fourth actuator sensor 72c, 72d monitor the rotation of first and second electrical motors 18,42.In an example of the present disclosure, the third and fourth actuator sensor 72c, 72d are the absolute angle coder

Referring now to Fig. 2 and Fig. 3, flow-controlling gate 56a-56d will be described.Since first, second, third with the 4th flow-controlling gate 56a-56d in each is structurally similar, the first, second, third and the 4th flow-controlling gate 56a-56d will be referred to as flow-controlling gate 56.Flow-controlling gate 56 comprises at least one leader stage spool 80 and at least one main stage spool 82.In embodiment shown in Figure 3, flow-controlling gate 56 comprises the first leader stage spool 80a and the second leader stage spool 80b and the first main stage spool 82a and the second main stage spool 82b.

By the fluid pressure of corrective action in the first and second main stage spool 82a, any end of 82b, the position of the first and second leader stage spool 80a, 80b is controlled the position of the first and second main stage spool 82a, 82b respectively.The position control of the first and second main stage spool 82a, 82b is to the rate of flow of fluid of cooresponding actuator 58.

The position of the first and second leader stage spool 80a, 80b is controlled by the first and second actuator 84a, 84b.In an example of the present disclosure, the first and second actuator 84a, 84b are electromagnetic actuators, for example voice coil loudspeaker voice coil.

The first and second valve core position sensor 86a, 86b measure the position of the first and second main stage spool 82a, 82b and will send to controller 60 corresponding to the first and second signal 88a, the 88b of the first and second main stage spool 82a, 82b position.In an example of the present disclosure, the first and second valve core position sensor 86a, 86b are linear variable differential transmitter (LVDT).

Referring now to Fig. 1,2 and Fig. 4, controller 60 is suitable for from the signal of described a plurality of actuator sensor 72 receptions about described a plurality of actuators 58, and from the signal of described a plurality of valve core position sensors 86 receptions about main stage spool 82 positions of flow-controlling gate 56.In addition, controller 60 is suitable for from the input 90 of operator's reception about desired output.Controller 60 sends to signal 92 the first and second actuator 84a, the 84b of flow-controlling gate 56a-56d to activate described a plurality of actuator 58.In an example of the present disclosure, signal 92 is a pulse-width signal.

In embodiment shown in Figure 2, controller 60 is shown as single controller.Yet in an example of the present disclosure, controller 60 comprises a plurality of controllers.In another example of the present disclosure, described a plurality of controllers 60 are integrated in described a plurality of flow-controlling gate 56.

Controller 60 comprises action controlling schemes 100.Action controlling schemes 100 is a closed loop co-operative control scheme.Action controlling schemes 100 comprises tracking generator, coordinate transformation module 104, deflection compensated module 106, axle control module 108 and input shaper module 110.

Tracking generator produces the expectation Carttesian coordinates X that the end that is used for working truck 10 is implemented device (for example job platform 38) based on the input 90 from the operator _d=[x ₀, y ₀, z ₀, φ ₀] ^TCartesian coordinates comprises terminal position and the orientation of implementing device.

In an example of the present disclosure, coordinate transformation module 104 comprises the first coordinate transformation module 104a and the second coordinate transformation module 104b.The first coordinate transformation module 104a is transformed into joint space with coordinate from cartesian space.The second coordinate transformation module 104b is transformed into the actuator space with coordinate from joint space.Table I has been listed for the independent variable of described a plurality of actuators 58 in cartesian space, joint space and actuator space.

Cartesian space	Joint space	The actuator space
			x 0	θ 1	θ 1
y 0	θ 2	L AB
			z 0	l 3	l 3
φ 0	θ 5	θ 5

Relation between Table I-cartesian space, joint space and the actuator space

The first coordinate transformation module 104a will expect Cartesian coordinates X _dBe transformed into the expectation coordinate Θ in the joint space _d=[θ ₁, θ ₂, l ₃, θ ₅] ^TThe forward transform formula of Cartesian coordinates is provided by following formula:

$X^{i-1}=T_i^{i-1}{X}^i,---\left(112\right)$

Wherein, X ⁱBe to have initial point O _iO _i-x _iy _iz _iPosition vector [x in the frame of reference ⁱ, y ⁱ, z ⁱ, 1] ^T

Provide by following formula:

$T_i^{i-1}=\left[\begin{array}{cccc}{\cos \mathrm{\θ}}_i& -\sin {\mathrm{\θ}}_i\cos {\mathrm{\α}}_i& \sin {\mathrm{\θ}}_i\sin {\mathrm{\α}}_i& a_i\cos {\mathrm{\θ}}_i\\ \sin {\mathrm{\θ}}_i& \cos {\mathrm{\θ}}_i\cos {\mathrm{\α}}_i& -\cos {\mathrm{\θ}}_i\sin {\mathrm{\α}}_i& a_i\sin {\mathrm{\θ}}_i\\ 0& \sin {\mathrm{\α}}_i& \cos {\mathrm{\α}}_i& d_i\\ 0& 0& 0& 1\end{array}\right],---\left(114\right)$

It is O _i-x _iy _iz _iFrame of reference is with respect to last frame of reference O _I-1-x _I-1y _I-1z _I-1Homogeneous transformation (position and orientation), wherein, i=1,2 ..., 5.

For with respect to O _I-1-x _I-1y _I-1z _I-1O _i-x _iy _iz _iThe direction cosine of coordinate axle, Be O _I-1At O _I-1-x _I-1y _I-1z _I-1Position in the frame of reference.

In formula 114, the Denavit-Hartenberg labelling method is used to describe kinematic relation.a _iBe the length of common normal, d _iBe initial point O _I-1Arrive z with common normal _I-1Point of crossing between distance, α _iBe joint shaft z _iAnd z _I-1Between with respect to z _I-1Angle, θ _iBe x _I-1And between the common normal with respect to z _I-1Angle.The parameter of job platform 38 provides in Table II.

Table II. the parameter of the Denavit-Hartenberg conversion of the coordinate of Fig. 1 definition

The terminal device position of implementing can (be θ by using the joint displacements value in the equation 116 below with orientation ₁, θ ₂, l ₃, θ ₄, θ ₅) obtain.Under this particular condition, θ ₄Not independent variable, because as shown in Figure 1, θ ₄=θ ₂

$T_5^0={\mathrm{<figure-callout\; id="1"\; label="T"\; filenames="HDA0000068298000000061.png"\; state="\{\{state\}\}">T</figure-callout>}}_1^0\left({\mathrm{\&theta;}}_1\right)T_2^1\left({\mathrm{\&theta;}}_2\right)T_3^2\left({\mathrm{\&theta;}}_3\right)T_4^3\left({\mathrm{\&theta;}}_4\right)T_5^4\left({\mathrm{\&theta;}}_5\right).---\left(116\right)$

For solving equation 116, get initial point O ₅-x ₅y ₅z ₅, O ₅For end is implemented device.If O ₅With respect to O ₀-x ₀y ₀z ₀The position be [x ₀, y ₀, z ₀] ^T, and x ₅With x ₀Between angle be φ ₀, then have O ₀-x ₀y ₀z ₀Middle O ₅-x ₅y ₅z ₅The homogeneous transformation matrix:

$T_5^0=\left[\begin{array}{cccc}\cos {\mathrm{\&phi;}}_0& \sin {\mathrm{\&phi;}}_0& 0& x_0\\ \sin {\mathrm{\&phi;}}_0& -\cos {\mathrm{\&phi;}}_0& 0& y_0\\ 0& 0& 0& z_0\\ 0& 0& 0& 1\end{array}\right].---\left(118\right)$

Multiply by at equation 118 two ends

Obtain following equation:

${{\mathrm{<figure-callout\; id="1"\; label="T"\; filenames="HDA0000068298000000061.png"\; state="\{\{state\}\}">T</figure-callout>}}_1^0{\left({\mathrm{\&theta;}}_1\right)}^{-1}T}_5^0=T_2^1\left({\mathrm{\&theta;}}_2\right)T_3^2\left({\mathrm{\&theta;}}_3\right)T_4^3\left({\mathrm{\&theta;}}_4\right)T_5^4\left({\mathrm{\&theta;}}_5\right),---\left(120\right)$

Its representative is at O ₁-x ₁y ₁z ₁O in the frame of reference ₅The equation 118 and 120 the left side obtain:

$\left[\begin{array}{cccc}\cos {\mathrm{\&theta;}}_1& \sin {\mathrm{\&theta;}}_1& 0& -L_{O_0{\mathrm{<figure-callout\; id="1"\; label="O"\; filenames="HDA0000068298000000061.png"\; state="\{\{state\}\}">O</figure-callout>}}_1}\\ 0& 0& 1& 0\\ \sin {\mathrm{\&theta;}}_1& -\cos {\mathrm{\&theta;}}_1& 0& 0\\ 0& 0& 0& 1\end{array}\right]\left[\begin{array}{cccc}\cos {\mathrm{\&phi;}}_0& \sin {\mathrm{\&phi;}}_0& 0& x_0\\ \sin {\mathrm{\&phi;}}_0& -\cos {\mathrm{\&phi;}}_0& 0& y_0\\ 0& 0& 0& z_0\\ 0& 0& 0& 1\end{array}\right]=$ .(122)

$\left[\begin{array}{cccc}\cos {\mathrm{\&theta;}}_1\cos {\mathrm{\&phi;}}_0+\sin {\mathrm{\&theta;}}_1\sin {\mathrm{\&phi;}}_0& *& *& x_0\cos {\mathrm{\&theta;}}_1+y_0\sin {\mathrm{\&theta;}}_1-L_{O_0{\mathrm{<figure-callout\; id="1"\; label="O"\; filenames="HDA0000068298000000061.png"\; state="\{\{state\}\}">O</figure-callout>}}_1}\\ *& *& *& z_0\\ *& *& *& x_0\sin {\mathrm{\&theta;}}_1-y_0\cos {\mathrm{\&theta;}}_1\\ *& *& *& *\end{array}\right]$

The right of equation 120 obtains:

$\left[\begin{array}{cccc}\cos {\mathrm{\&theta;}}_5& *& *& {-l}_3\sin {\mathrm{\&theta;}}_2\\ *& *& *& l_3\cos {\mathrm{\&theta;}}_2\\ *& *& *& 0\\ *& *& *& *\end{array}\right].---\left(124\right)$

By equation 122 and 124, Cartesian coordinates to joint coordinates conversion can be formulated as:

$\mathrm{\&Theta;}\left(X\right):=\left[\begin{array}{c}{\mathrm{\&theta;}}_1\\ {\mathrm{\&theta;}}_2\\ l_3\\ {\mathrm{\&theta;}}_5\end{array}\right]=\left[\begin{array}{c}\arctan \left(\frac{y_0}{x_0}\right)\\ \arctan \left(\frac{L_{O_0{O}_1}-x_0\cos {\mathrm{\&theta;}}_1-y_0\sin {\mathrm{\&theta;}}_1}{z_0}\right)\\ \frac{z_0}{\cos {\mathrm{\&theta;}}_2}\\ {\mathrm{\&phi;}-\mathrm{\&theta;}}_1\end{array}\right].---\left(126\right)$

Now with reference to Fig. 1,2,4 and 5 deflection compensated module 106 is described.Cartesian coordinates X in expectation _dBe converted into the expectation coordinate Θ in the joint space _dSituation under, deflection compensated module 106 is taken the deflection of arm component 20 into account.Deflection compensated module 106 receives the result of a measurement from described a plurality of actuator sensor 72, the actual axle of the described a plurality of actuators 58 of actuator sensor 72 monitorings to and/or position of rotation.Utilize these result of a measurement, the cooresponding error correcting that deflection compensated module 106 is calculated in the joint space.

For long flexible structure, for example arm component 20, and the deflection of this structure can cause the desirable terminal big error of implementing between device coordinate and the actual end enforcement device coordinate.This offset error is the terminal function of implementing the device coordinate.For instance, for different adjustable heights and length, deflection will be different.As shown in Figure 5, the offset error in the joint space is mainly from the angle of rotation θ of arm component 20 ₂It is little to ignore ground for the offset error of other degree of freedom.Therefore, δ Θ=[0, δ θ ₂, 0,0] ^T

The metastability analysis of deflection compensated is provided below.It is suitable in this case that this metastability is analyzed, because the result of the input shaper module 110 that conduct will be introduced below in more detail, the vibration of arm component 20 is reduced or eliminates.

The deflection of arm component 20 is acted on the gravity of arm component 20 and is acted on the influence of the load of job platform 38.The deflection of arm component 20 is length l of arm component 20 ₃Anglec of rotation θ with arm component 20 ₂Function.Suppose that arm component 20 has the consistent cross-sectional plane that distributes, deflection can use following equation to calculate:

$\mathrm{\&delta;}(l_3,{\mathrm{\&theta;}}_2)=(\frac{\mathrm{mg}{l}_3^3}{3\mathrm{EI}}+\frac{\mathrm{\&rho;g}{l}_3^4}{8\mathrm{EI}})\sin {\mathrm{\&theta;}}_2,---\left(128\right)$

Wherein, E is the modulus of elasticity of arm material, and I is the moment of inertia of the cross-sectional plane of arm, and ρ is a quality length density, and m is the quality of load.If δ is θ ₂:=θ ' ₂-θ ₂Provide by following equation, then have anglec of rotation θ ' ₂The rigid arm assembly can have identical apical position:

$\mathrm{\&delta;}{\mathrm{\&theta;}}_2(l_3,{\mathrm{\&theta;}}_2)=\frac{\mathrm{\&delta;}(l_3,{\mathrm{\&theta;}}_2)}{l_3}=(\frac{\mathrm{mg}{l}_3^2}{3\mathrm{EI}}+\frac{\mathrm{\&rho;g}{l}_3^3}{8\mathrm{EI}})\sin {\mathrm{\&theta;}}_2.---\left(130\right)$

Equation 130 is in joint space, and the actual measured results of actuator sensor 72 is in the actuator space.Therefore, for this conversion, will need actuator to the joint space conversion.

Referring now to Fig. 1,2,4,6 explanations, the second coordinate transformation module 104b.The expectation coordinate Θ that the second coordinate transformation module 104b obtains the result in the joint space _d=Θ _d+ δ Θ is transformed into the actuator space.The actuator space is with reference to described a plurality of actuators 58.In an example of the present disclosure, the actuator space is with reference to first and second cylinders 22,34 and first and second electrical motors 18,42.The Table I that provides has above been listed the independent variable in cartesian space, joint space and actuator space.The independent variable θ of joint space ₁, θ ₂And θ ₅With exist between the corresponding independent variable in actuator space directly corresponding.Yet, now l will be described ₃And L _ABBetween relation.

Referring now to Fig. 6, the scheme drawing of the arm component 20 and first cylinder 22.First end 24 that second end of first cylinder 22 is installed to car body 16, the first cylinders 22 of working truck 10 at the A point is installed to arm component 20 at the B point.The A point is the frame of reference O that is associated with car body 16 ₁-x ₁y ₁z ₁In attachment point, and the B point is the frame of reference O that is associated with arm component 20 ₂-x ₂y ₂z ₂In attachment point.Between A point and B point apart from l _ABAnglec of rotation θ for arm component 20 ₂Function, and can use following formula to calculate:

$l_{\mathrm{AB}}\left({\mathrm{\&theta;}}_2\right)=\sqrt{{\mathrm{<figure-callout\; id="1"\; label="L\; BO"\; filenames="HDA0000068298000000061.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{\mathrm{BO}}_{}}^{{}_1}+{\mathrm{<figure-callout\; id="1"\; label="L\; AO"\; filenames="HDA0000068298000000061.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{\mathrm{AO}}_{}}^{{}_1}-2L_{{\mathrm{AO}}_1}{\mathrm{<figure-callout\; id="1"\; label="L\; BO"\; filenames="HDA0000068298000000061.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{\mathrm{BO}}_{}}\cos \&angle;{\mathrm{BO}}_{1}A\left({\mathrm{\&theta;}}_2\right)},---\left(132\right)$

Wherein, ∠ BO ₁A (θ ₂)=90 °+∠ O ₀O ₁A-θ ₂-∠ BO ₁O ₃

So joint to actuator spatial alternation is:

$Y\left(\mathrm{\&Theta;}\right):=\left[\begin{array}{c}{\mathrm{\&theta;}}_1\\ l_{\mathrm{AB}}\left({\mathrm{\&theta;}}_2\right)\\ l_3\\ {\mathrm{\&theta;}}_5\end{array}\right].---\left(134\right)$

The expectation coordinate Θ that obtains in the result _dBe switched to the actuator space Y _d=[θ ₁, L _AB, l ₃, θ ₅] ^TSituation under, the expectation coordinate Y that the result obtains _dWith actual measured results Y from described a plurality of actuator sensor 72 _aReceive by axle control module 108.Axle control module 108 generates the control signal U that is used for flow-controlling gate 56.

Control signal U is flow order q _nVector.Flow order q _nCorresponding with described a plurality of sensor 58.In an example of the present disclosure, velocity feed forward proportional integral (PI) (PI) controller is used to generate flow order q _nVelocity feed forward PI controller can be:

$q_n=K_{f,n}{\stackrel{.}{y}}_{d,n}+K_{p,n}(y_{d,n}-y_{a,n})+K_{i,n}\&Integral;(y_d-y_a)\mathrm{dt},---\left(136\right)$

Wherein, q _nFor being used for the flow order of valve n, K _{F, n}, K _{P, n}, K _{I, n}Be respectively feedforward, ratio and storage gain, and y _{D, n}And y _{A, n}Be axle n=1,2,3,4 expectation and actual displacement.For first and second cylinders 22,34, gain K _{F, n}, K _{P, n}, K _{I, n}Will be owing to the former of piston area ratio thereby different slightly for each direction.

The exemplary control signal U that is generated by axle control module 108 is U=[q ₁, q ₂, q ₃, q ₄] ^TIn an example of the present disclosure, flow-controlling gate 56 comprises embedded pressure sensor 70, embedded valve core position sensor 88 and internal piloting ring.These sensors and internal piloting ring allow axle control module 108 directly to flow-controlling gate 56 transmitted traffic order q _n, the spool position command is opposite with sending.

Referring now to Fig. 1 and 4 explanation input shaper modules 110.Input shaper module 110 is suitable for reducing the structural vibration in the arm component 20 of working truck 10.

The input shaper scheme suppresses vibration by producing through the order input of shaping.The influence of modeling error can reduce by the pulse number that increases in the input shaper scheme.But along with the increase of the pulse number in the input shaper scheme, the responsibility of order input reduces.

In an example of the present disclosure, the input shaper scheme is a time-varying input shaping scheme.The amount that time-varying input shaping scheme reduces to vibrate simultaneously, keeps good responsibility.In an example of the present disclosure, time-varying input shaping scheme is only used two pulses.In addition, time-varying input shaping scheme uses result of a measurement from described a plurality of actuator sensor 72 so that the control signal with time-varying parameter to be provided.

At first, time-varying input shaping scheme is according to the actual measured results Y from described a plurality of actuator sensor 72 _aInfer the dampingratio (t) and the natural frequency ω of arm component 20 _n(t).The formula of damping ratio and natural frequency is:

ζ(t)＝f _ζ(Y _a)＝f _ζ(l ₃(t))， (138)

ω _n(t)＝f _ω(Y _a)＝f _ω(l ₃(t))， (140)

Wherein, f _ζAnd f _ωBe length l based on arm component 20 ₃Function.Suppose l ₃For the unique advantage control variable in all measurands and can to ignore ground from the influence of load little, these function f _ζAnd f _ωCan calibrate by experiment to determine, or determine by modeling.In an example of the present disclosure, damping ratio function and natural frequency function f are determined in flow-controlling gate 56 respectively _ζAnd f _ω56 pairs of damping ratio function f of flow-controlling gate _ζWith the natural frequency function f _ωDefinite mode will be in following work specific description more.

Next, the amplitude of two pulses is provided by following formula:

$A_1\left(t\right)=\frac{1}{1+K\left(t\right)}---\left(142\right)$

$A_2\left(t\right)=\frac{K\left(t\right)}{1+K\left(t\right)},---\left(144\right)$

Wherein, $K\left(t\right)=\exp \left(\frac{\mathrm{\&zeta;}\left(t\right)\mathrm{\&pi;}}{\sqrt{1-\mathrm{\&zeta;}{\left(t\right)}^2}}\right)$

The time delay of each pulse is:

ΔT ₁(t)＝0 (146)

${\mathrm{\&Delta;T}}_2=\frac{\mathrm{\&pi;}}{{\mathrm{\&omega;}}_n\left(t\right)\sqrt{1-\mathrm{\&zeta;}{\left(t\right)}^2}}.---\left(148\right)$

At last, through the control signal U of shaping _sProvide by following formula:

$U_s=\left[\begin{array}{c}{q}_1\\ A_1\left(t\right)U_2(t-\mathrm{\&Delta;}{T}_1\left(t\right)+A_2\left(t\right)U_2(t-\mathrm{\&Delta;}{T}_2\left(t\right))\\ q_3\\ q_4\end{array}\right].---\left(150\right)$

Control signal U through shaping _sBe sent to flow-controlling gate 56, so that fluid can be by flow-controlling gate 56 to actuator 58, with mobile operating platform 38.As previously mentioned, input shaper module 110 may be favourable, because it reduces or eliminates the vibration of arm component 20, simultaneously, the responsibility of keeping arm assembly 20.

Referring now to Fig. 1 and 7, will illustrate and determine dampingratio (t) and natural frequency ω _n(t) illustrative methods 200.In step 202, actuator is caused is driven into primary importance.For instance, first and second cylinders 22,34 be moved within the consideration position of damping ratio and natural frequency (for example, first and second cylinders, 22,34 full extension, first and second cylinders, 22,34 parts stretch, or the like).

In step 204, make arm component 20 vibrations.In an example of the present disclosure, make arm component 20 vibrate by apply power to arm component 20.In another example of the present disclosure, the input media that moves by quick travel working truck upper suspension arm assembly 20 (for example, joystick etc.) makes arm component 20 vibrations.This brief burst that gives hydraulic fluid to first and/or second cylinder 22,34 that moves, it makes arm component 20 vibrate.

In step 206, dampingratio (t) and natural frequency ω _n(t) be calibrated.In an example of the present disclosure, the mensuration of damping ratio and natural frequency is finished by flow-controlling gate 56.

Method 300 now with reference to Fig. 1,7 and 8 explanation use traffic control cock 56 calibration damping ratios and natural frequency.In step 302, period counter N is set to initial value, and for example 1.Because flow-controlling gate 56 comprises integrated pressure sensor 70, flow-controlling gate 56 receives the signal from pressure sensor 70 in step 304.In step 306, the pressure P when flow-controlling gate 56 record pressure signals are in its peak (peak value) _{HI, 1}With peak pressure P _{HI, 1}The moment t that occurs _{HI, 1}In step 308, the pressure P when flow-controlling gate 56 is also write down pressure signal and is in its minimum (valley) _{LO, 1}And pressure P _{LO, 1}The moment t that occurs _{LO, 1}

In step 310, period counter N is adjusted (index) (N=N+1) when pressure is positioned at its next peak value.In step 312, compare cycle counting machine N and predetermined value.If period counter N equals predetermined value, in step 314, the pressure P when flow-controlling gate 56 record pressure signals are in its peak (peak value) for this period demand _{HI, 2}With peak pressure P _{HI, 2}Moment t for this period demand appearance _{HI, 2}In step 316, the pressure P when flow-controlling gate 56 is also write down pressure signal and is in its minimum (valley) for this period demand _{LO, 2}And pressure P _{LO, 2}Moment t for this period demand appearance _{LO, 2}

In step 318, calculate natural frequency ω _n(t).Can use following formula to calculate the natural frequency ω of the very big electrically little damping system of vibration _n(t):

${\mathrm{\&omega;}}_n\&ap;\frac{2\mathrm{\&pi;N}}{t_{\mathrm{HI},2}-t_{\mathrm{HI},1}}.---\left(152\right)$

In step 320, calculate dampingratio (t).Dampingratio (t) is for being described in measuring that how vibration in the arm component 20 decays after the disturbance.Amplitude is provided by following formula:

$\frac{\exp (-\mathrm{\&zeta;}{\mathrm{\&omega;}}_n{t}_{\mathrm{HI},2})}{\exp (-\mathrm{\&zeta;}{\mathrm{\&omega;}}_n{t}_{\mathrm{HI},1})}=\exp (-\mathrm{\&zeta;}{\mathrm{\&omega;}}_n(t_{\mathrm{HI},2}-t_{\mathrm{HI},1})=\frac{P_{\mathrm{HI},2}-P_{\mathrm{LO},2}}{P_{\mathrm{HI},1}-P_{\mathrm{LO},1}}.---\left(154\right)$

Formula 154 separate for:

$\mathrm{\&zeta;}=\frac{-\log \left(\frac{P_{\mathrm{HI},2}-P_{\mathrm{LO},2}}{P_{\mathrm{HI},1}-P_{\mathrm{LO},1}}\right)}{\frac{{\mathrm{\&omega;}}_n}{t_{\mathrm{HI},2}-t_{\mathrm{HI}-1}}}.---\left(156\right)$

Again with reference to Fig. 1 and 7, under the situation that damping ratio and natural frequency obtain calculating for given actuator 58 positions, in step 208, actuator 58 is moved to the second place, use step 204-206, determine dampingratio (t) and natural frequency ω for this actuator position _n(t).

Though damping ratio and natural frequency are only calibrated on discrete actuator position, can use interpolation method to come to determine damping ratio and natural frequency for other actuator position beyond these discrete actuator positions.In an example of the present disclosure, can use linear interpolation.

Under situation about not departing from the scope of the present invention with spirit, those skilled in the art will envision that multiple modification of the present disclosure and replacement, should be appreciated that the scope of the present disclosure is not limited to exemplary embodiment given herein.

Claims (20)

1. method that is used for the Control arm assembly, described method comprises:

Provide to have the terminal arm component of implementing device, described arm component comprises the actuator that is communicated with the flow-controlling gate fluid;

The described terminal expectation coordinate of implementing device of described arm component is transformed into the actuator space from cartesian space;

According to the displacement that measures of described actuator, calculate the described terminal offset error of implementing device;

According to described expectation coordinate and described offset error, the expectation coordinate that result of calculation obtains;

The expectation coordinate that obtains according to described result and the displacement that measures of described actuator generate control signal;

Described control signal is carried out shaping, to reduce the vibration of described arm component; And

To the control signal of described flow-controlling gate transmission through shaping.

2. the method for claim 1, wherein use time-varying input shaping scheme that described control signal is carried out shaping.

3. method as claimed in claim 2, wherein, described time-varying input shaping scheme comprises two pulses.

4. the method for claim 1, wherein first coordinate transform is transformed into joint space with described expectation coordinate from cartesian space, and second coordinate transform is transformed into the actuator space with described expectation coordinate from joint space.

5. method as claimed in claim 4, wherein, described offset error provides with the joint space coordinate.

6. the method for claim 1, wherein described control signal through shaping is provided by following formula:

$U_s=\left[\begin{array}{c}{q}_1\\ A_1\left(t\right)U_2(t-\mathrm{\&Delta;}{T}_1\left(t\right)+A_2\left(t\right)U_2(t-\mathrm{\&Delta;}{T}_2\left(t\right))\\ q_3\\ q_4\end{array}\right].$

7. the method for claim 1, wherein described actuator sensor is a laser sensor.

8. the method for claim 1, wherein described actuator sensor is the absolute angle coder.

9. working truck comprises:

Has the terminal arm component of implementing device;

Join the actuator of described arm component to, wherein, described actuator is applicable to described arm component is positioned;

Actuator sensor is applicable to the displacement of measuring described actuator;

The flow-controlling gate that is communicated with described actuator fluid;

With the controller of described flow-controlling gate electrical communication, described controller is applicable in response to incoming signal ground described flow-controlling gate is activated that wherein, described controller comprises the action controlling schemes, and the action controlling schemes comprises:

Coordinate transformation module, the expectation coordinate that the described end of described arm component is implemented device is transformed into the actuator space from cartesian space;

The deflection compensated module according to the result of a measurement from described actuator sensor, is calculated the described terminal offset error of implementing device;

The axle control module according to described expectation coordinate, described offset error with from the result of a measurement of described actuator sensor, generates control signal; And

The input shaper module is carried out shaping to the described control signal that sends to described flow-controlling gate, to reduce the vibration of described arm component.

10. working truck as claimed in claim 9, wherein, described working truck is the aerial work platform.

11. working truck as claimed in claim 9, wherein, described terminal enforcement device is a job platform.

12. working truck as claimed in claim 9, wherein, described flow-controlling gate comprises a plurality of pressure sensors that are integrated in the described flow-controlling gate.

13. working truck as claimed in claim 9, wherein, described input shaper module is a time-varying input shaping scheme.

14. working truck as claimed in claim 13, wherein, described time-varying input shaping scheme comprises only two pulses.

15. working truck as claimed in claim 13, wherein, described time-varying input shaping scheme is according to the damping ratio and the natural frequency of inferring described arm component from the result of a measurement of described actuator sensor.

16. working truck as claimed in claim 15, wherein, described flow-controlling gate is identified for inferring the damping ratio function and the natural frequency function of damping ratio and natural frequency.

17. the damping ratio of a use traffic control cock calibration arm assembly and the method for natural frequency, described method comprises:

From the pressure signal of pressure sensor reception about the pressure the actuator;

For the period 1, record height and low pressure values and the moment that is associated with these force value;

For second round, record height and low pressure values and the moment that is associated with these force value; And

According to for the described force value in first and second cycles and the moment that is associated with these force value, calculate natural frequency and damping ratio.

18. method as claimed in claim 17, wherein, described pressure sensor is integrated in the described flow-controlling gate.

19. the method that the control signal that is used for flexible structure is carried out shaping, described method comprises:

Produce control signal according to the expectation coordinate;

Use time-varying input shaping scheme that described control signal is carried out shaping, wherein, described time-varying input shaping scheme:

Receive result of a measurement from sensor;

According to the result of a measurement of described sensor, infer the natural frequency and the damping ratio of described flexible structure; And

According to described result of a measurement and natural frequency of inferring and damping ratio, described control signal is carried out shaping.

20. method as claimed in claim 19, wherein, described control signal is based on such expectation coordinate that the result obtains: it will be taken into account with the offset error that described flexible structure is associated.

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