Methods and devices for detecting hydraulic cylinder parameters and control methods for operating machinery.

Abstract

This invention relates to the field of work machinery, providing a method, device, and control method for detecting hydraulic cylinder parameters. The detection method includes: acquiring first operating parameters of the hydraulic cylinder; inputting the first operating parameters into a pre-constructed digital cylinder model to obtain second operating parameters of the hydraulic cylinder to be detected; the digital cylinder model is established based on the state-space equation of the hydraulic cylinder, which characterizes the functional relationship between the second operating parameters and the first operating parameters. Through the pre-constructed digital cylinder model, the second operating parameters of the hydraulic cylinder can be obtained based on the first operating parameters. Since the digital cylinder model is established using the state-space equation of the hydraulic cylinder, the detection of hydraulic cylinder parameters can be achieved without installing multiple sensors, resulting in lower detection costs and higher reliability. This solves the problems of high cost and low reliability associated with obtaining hydraulic cylinder parameters using multiple sensors.

Description

Technical Field

[0001] This invention relates to the field of machinery technology, and in particular to a method and device for detecting hydraulic cylinder parameters and a control method for machinery. Background Technology

[0002] To ensure precise control of the operating actions of machinery, it is necessary to obtain the hydraulic cylinder parameters of the machinery. Currently, this is mainly achieved by installing various sensors in the hydraulic system to obtain the hydraulic cylinder parameters in real time, such as hydraulic cylinder displacement sensors and pressure sensors.

[0003] However, various sensors are costly to install, use and maintain, and the reliability of the hydraulic cylinder parameters they detect is low. Summary of the Invention

[0004] This invention provides a method, device, and control method for detecting hydraulic cylinder parameters, which solves the problems of existing technologies that obtain hydraulic cylinder parameters through multiple sensors, which are costly to install, use, and maintain, and have low reliability of the detected hydraulic cylinder parameters.

[0005] In a first aspect, the present invention provides a method for detecting parameters of a hydraulic cylinder, the method comprising:

[0006] Obtain the first operating parameters of the hydraulic cylinder;

[0007] The first working condition parameters are input into a pre-built digital cylinder model to obtain the second working condition parameters to be detected for the hydraulic cylinder.

[0008] The digital cylinder model is established based on the state-space equation of the hydraulic cylinder, which is used to characterize the functional relationship between the second working condition parameter and the first working condition parameter.

[0009] According to the method for detecting hydraulic cylinder parameters provided by the present invention, obtaining the second operating condition parameter to be detected of the hydraulic cylinder includes:

[0010] The current pressure of the rodless cavity included in the second operating condition parameters is determined based on the first functional relationship; wherein, the first functional relationship is the relationship between the current pressure of the rodless cavity and the inflow and outflow rates of the rodless cavity, the initial displacement of the piston, and the initial velocity of the piston included in the first operating condition parameters;

[0011] And / or, determine the current pressure of the rod chamber included in the second operating condition parameters based on the second functional relationship; wherein, the second functional relationship is the relationship between the current pressure of the rod chamber and the inflow and outflow rates of the rod chamber, the initial displacement of the piston, and the initial velocity of the piston included in the first operating condition parameters;

[0012] And / or, the hydraulic cylinder output force included in the second operating condition parameters is determined based on a third functional relationship; wherein, the third functional relationship is the relationship between the hydraulic cylinder output force and the inflow and outflow rates of the rodless chamber, the inflow and outflow rates of the rod chamber, the initial piston displacement, and the initial piston velocity included in the first operating condition parameters;

[0013] And / or, determine the current piston displacement included in the second operating condition parameters based on the fourth functional relationship; wherein, the fourth functional relationship is the relationship between the current piston displacement and the inflow and outflow rates of the rodless cavity, the inflow and outflow rates of the rod cavity, the initial piston displacement, and the initial piston velocity included in the first operating condition parameters;

[0014] And / or, determine the current piston speed included in the second operating condition parameters based on the fifth functional relationship; wherein, the fifth functional relationship is the relationship between the current piston speed and the inflow and outflow rates of the rodless chamber, the inflow and outflow rates of the rod chamber, the initial piston displacement, and the initial piston speed included in the first operating condition parameters.

[0015] According to the hydraulic cylinder parameter detection method provided by the present invention, the step of determining the current pressure of the rodless chamber included in the second operating condition parameters based on a first functional relationship includes:

[0016] Based on the initial displacement of the piston and the pre-obtained effective area of ​​the rodless cavity, the effective volume of the rodless cavity is obtained;

[0017] Based on the initial velocity of the piston and the effective area of ​​the rodless cavity, the derivative of the effective volume of the rodless cavity is obtained;

[0018] The current pressure of the rodless cavity is obtained based on the inflow and outflow rates of the rodless cavity, the effective volume of the rodless cavity, and the derivative of the effective volume of the rodless cavity.

[0019] According to the hydraulic cylinder parameter detection method provided by the present invention, the step of determining the current pressure of the rod chamber included in the second operating condition parameters based on the second functional relationship includes:

[0020] Based on the initial displacement of the piston and the pre-obtained effective area of ​​the rod cavity, the effective volume of the rod cavity is obtained.

[0021] Based on the initial velocity of the piston and the effective area of ​​the rod chamber, the derivative of the effective volume of the rod chamber is obtained;

[0022] The current pressure of the rod cavity is obtained based on the inflow and outflow rates of the rod cavity, the effective volume of the rod cavity, and the derivative of the effective volume of the rod cavity.

[0023] According to the method for detecting hydraulic cylinder parameters provided by the present invention, the step of determining the hydraulic cylinder output force included in the second operating condition parameters based on a third functional relationship includes:

[0024] Based on the initial displacement of the piston and the pre-obtained effective area of ​​the rodless cavity, the effective volume of the rodless cavity is obtained;

[0025] Based on the initial velocity of the piston and the effective area of ​​the rodless cavity, the derivative of the effective volume of the rodless cavity is obtained;

[0026] The current pressure of the rodless cavity is obtained based on the inflow and outflow rates of the rodless cavity, the effective volume of the rodless cavity, and the derivative of the effective volume of the rodless cavity.

[0027] Based on the initial displacement of the piston and the pre-obtained effective area of ​​the rod cavity, the effective volume of the rod cavity is obtained.

[0028] Based on the initial velocity of the piston and the effective area of ​​the rod chamber, the derivative of the effective volume of the rod chamber is obtained;

[0029] The current pressure of the rod cavity is obtained based on the inflow and outflow rates of the rod cavity, the effective volume of the rod cavity, and the derivative of the effective volume of the rod cavity.

[0030] Based on the initial piston velocity and the pre-obtained damping coefficient, the frictional resistance during piston movement is obtained;

[0031] The output force of the hydraulic cylinder is obtained based on the current pressure of the rodless chamber, the current pressure of the rod chamber, and the frictional resistance during piston rod movement.

[0032] According to the hydraulic cylinder parameter detection method provided by the present invention, the step of determining the current piston displacement included in the second operating condition parameter based on the fourth functional relationship includes:

[0033] Based on the initial displacement of the piston and the pre-obtained effective area of ​​the rodless cavity, the effective volume of the rodless cavity is obtained;

[0034] Based on the initial velocity of the piston and the effective area of ​​the rodless cavity, the derivative of the effective volume of the rodless cavity is obtained;

[0035] The current pressure of the rodless cavity is obtained based on the inflow and outflow rates of the rodless cavity, the effective volume of the rodless cavity, and the derivative of the effective volume of the rodless cavity.

[0036] Based on the initial displacement of the piston and the pre-obtained effective area of ​​the rod cavity, the effective volume of the rod cavity is obtained.

[0037] Based on the initial velocity of the piston and the effective area of ​​the rod chamber, the derivative of the effective volume of the rod chamber is obtained;

[0038] The current pressure of the rod cavity is obtained based on the inflow and outflow rates of the rod cavity, the effective volume of the rod cavity, and the derivative of the effective volume of the rod cavity.

[0039] Based on the initial piston velocity and the pre-obtained damping coefficient, the frictional resistance during piston movement is obtained;

[0040] The hydraulic cylinder output force is obtained based on the current pressure of the rodless chamber, the current pressure of the rod chamber, and the frictional resistance during piston rod movement.

[0041] Based on the output force of the hydraulic cylinder and the mass sum of the piston rod and hydraulic cylinder load obtained in advance, the current acceleration of the piston is obtained;

[0042] The current displacement of the piston is obtained based on the initial displacement of the piston and the current acceleration of the piston.

[0043] According to the hydraulic cylinder parameter detection method provided by the present invention, the step of determining the current piston speed included in the second operating condition parameter based on the fifth functional relationship includes:

[0044] Based on the initial displacement of the piston and the pre-obtained effective area of ​​the rodless cavity, the effective volume of the rodless cavity is obtained;

[0045] Based on the initial velocity of the piston and the effective area of ​​the rodless cavity, the derivative of the effective volume of the rodless cavity is obtained;

[0046] The current pressure of the rodless cavity is obtained based on the inflow and outflow rates of the rodless cavity, the effective volume of the rodless cavity, and the derivative of the effective volume of the rodless cavity.

[0047] Based on the initial displacement of the piston and the pre-obtained effective area of ​​the rod cavity, the effective volume of the rod cavity is obtained.

[0048] Based on the initial velocity of the piston and the effective area of ​​the rod chamber, the derivative of the effective volume of the rod chamber is obtained;

[0049] The current pressure of the rod cavity is obtained based on the inflow and outflow rates of the rod cavity, the effective volume of the rod cavity, and the derivative of the effective volume of the rod cavity.

[0050] Based on the initial piston velocity and the pre-obtained damping coefficient, the frictional resistance during piston movement is obtained;

[0051] The hydraulic cylinder output force is obtained based on the current pressure of the rodless chamber, the current pressure of the rod chamber, and the frictional resistance during piston rod movement.

[0052] Based on the output force of the hydraulic cylinder and the mass sum of the piston rod and hydraulic cylinder load obtained in advance, the current acceleration of the piston is obtained;

[0053] The current velocity of the piston is obtained based on the initial velocity of the piston and the current acceleration of the piston.

[0054] Secondly, the present invention also provides a device for detecting hydraulic cylinder parameters, the device comprising:

[0055] The acquisition module is used to acquire the first operating parameters of the hydraulic cylinder;

[0056] The processing module is used to input the first working condition parameters into a pre-built digital cylinder model to obtain the second working condition parameters to be detected for the hydraulic cylinder.

[0057] The digital cylinder model is established based on the state-space equation of the hydraulic cylinder, which is used to characterize the functional relationship between the second working condition parameter and the first working condition parameter.

[0058] Thirdly, the present invention also provides a control method for a working machine, the method comprising:

[0059] The second operating parameters of the hydraulic cylinder are obtained by any of the above-described methods for detecting hydraulic cylinder parameters.

[0060] The operating actions of the machinery are controlled based on the second operating condition parameters.

[0061] Fourthly, the present invention also provides a working machine that uses the above-described control method for the working machine.

[0062] The method, device, and control method for detecting hydraulic cylinder parameters provided by this invention can obtain the second operating parameters of the hydraulic cylinder based on the first operating parameters of the hydraulic cylinder through a pre-constructed digital cylinder model. Since the digital cylinder model is established using the state-space equation of the hydraulic cylinder, the detection of hydraulic cylinder parameters can be achieved without installing multiple sensors. Compared with the method of obtaining hydraulic cylinder parameters through multiple sensors, the detection cost is lower and the detection reliability is higher. Attached Figure Description

[0063] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0064] Figure 1 This is a flowchart illustrating the method for detecting hydraulic cylinder parameters provided by the present invention;

[0065] Figure 2 This is a schematic diagram of the data input and output relationship of a digital hydraulic cylinder model;

[0066] Figure 3 This is a schematic diagram of the control principle of closed-loop control of hydraulic cylinders;

[0067] Figure 4 This is a simplified schematic diagram of a digital hydraulic cylinder model in an example of an excavator's hydraulic cylinder.

[0068] Figure 5 This is a schematic diagram of the structure of the hydraulic cylinder parameter detection device provided by the present invention;

[0069] Figure 6 This is a flowchart illustrating the control method for the operating machinery provided by the present invention;

[0070] Figure 7 This is a schematic diagram of the structure of the electronic device provided by the present invention. Detailed Implementation

[0071] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0072] The following is combined with Figures 1 to 7 The present invention describes a method for detecting hydraulic cylinder parameters, a device for detecting hydraulic cylinder parameters, a control method for operating machinery, and the operating machinery.

[0073] Figure 1 This invention illustrates a method for detecting hydraulic cylinder parameters, which can be applied to a hydraulic system controller and includes:

[0074] Step 101: Obtain the first operating parameters of the hydraulic cylinder;

[0075] Step 102: Input the first working condition parameters into the pre-built digital cylinder model to obtain the second working condition parameters to be tested for the hydraulic cylinder;

[0076] The digital cylinder model is based on the state-space equation of the hydraulic cylinder, which is used to characterize the functional relationship between the second working condition parameter and the first working condition parameter.

[0077] In an exemplary embodiment, the first operating parameters input to the digital cylinder model may specifically include: the inflow and outflow flow rates of the rodless chamber, the inflow and outflow flow rates of the rod chamber, the initial piston displacement, and the initial piston velocity.

[0078] The second operating condition parameters output from the digital cylinder model may specifically include: the current pressure of the rodless chamber, the current pressure of the rod chamber, the hydraulic cylinder output force, the current piston displacement, and / or the current piston speed.

[0079] Figure 2 The data input-output relationship of the above digital cylinder model is shown, where Q in (t) represents the inflow flow rates of the rodless cavity and the rod cavity at time t, Q out (t) represents the outflow rate of the rodless and rod chambers at time t, v(t) represents the piston velocity at time t, x(t) represents the piston displacement at time t, and F out (t+Δt) represents the hydraulic cylinder output force after a time step Δt, i.e., the outward thrust of the piston rod, P. head (t+Δt) represents the current pressure in the rodless cavity after a time step of Δt, P rod (t+Δt) represents the current pressure in the rod chamber after a time step of Δt, v(t+Δt) represents the piston velocity after a time step of Δt, and x(t+Δt) represents the piston displacement after a time step of Δt.

[0080] In addition, the data input into this digital cylinder model can also include the effective area A of the rodless chamber. head The effective area A of the rod cavity rod And the damping coefficient B, which is set to 10 in this embodiment. 5 In this embodiment, the effective area A of the rodless cavity is set. head The effective area A of the rod cavity rod The three parameters, including the damping coefficient B, are constant.

[0081] In an exemplary embodiment, the process of obtaining the second operating condition parameter to be detected for the hydraulic cylinder may specifically include:

[0082] The current pressure of the rodless cavity included in the second operating condition parameters is determined based on the first functional relationship; wherein, the first functional relationship is the relationship between the current pressure of the rodless cavity and the inflow and outflow rates of the rodless cavity, the initial displacement of the piston, and the initial velocity of the piston included in the first operating condition parameters;

[0083] And / or, determine the current pressure of the rod chamber included in the second operating condition parameters based on the second functional relationship; wherein, the second functional relationship is the relationship between the current pressure of the rod chamber and the inflow and outflow rates of the rod chamber, the initial displacement of the piston, and the initial velocity of the piston included in the first operating condition parameters;

[0084] And / or, determine the hydraulic cylinder output force included in the second working condition parameters based on the third functional relationship; wherein, the third functional relationship is the relationship between the hydraulic cylinder output force and the inflow and outflow rates of the rodless chamber, the inflow and outflow rates of the rod chamber, the initial piston displacement, and the initial piston velocity included in the first working condition parameters;

[0085] And / or, determine the current piston displacement included in the second operating condition parameters based on the fourth functional relationship; wherein, the fourth functional relationship is the relationship between the current piston displacement and the inflow and outflow rates of the rodless cavity, the inflow and outflow rates of the rod cavity, the initial piston displacement, and the initial piston velocity included in the first operating condition parameters;

[0086] And / or, determine the current piston speed included in the second operating condition parameters based on the fifth functional relationship; wherein, the fifth functional relationship is the relationship between the current piston speed and the inflow and outflow rates of the rodless cavity, the inflow and outflow rates of the rod cavity, the initial piston displacement, and the initial piston speed included in the first operating condition parameters.

[0087] Furthermore, the process of determining the current pressure of the rodless chamber included in the second operating condition parameters based on the first functional relationship may specifically include:

[0088] Based on the initial piston displacement and the pre-obtained effective area of ​​the rodless cavity, the effective volume of the rodless cavity is obtained.

[0089] Based on the initial piston velocity and the effective area of ​​the rodless cavity, the derivative of the effective volume of the rodless cavity is obtained;

[0090] The current pressure of the rodless cavity is obtained based on the inflow and outflow rates of the rodless cavity, the effective volume of the rodless cavity, and the derivative of the effective volume of the rodless cavity.

[0091] Furthermore, the process of determining the current pressure of the rod cavity included in the second operating condition parameters based on the second functional relationship may specifically include:

[0092] Based on the initial displacement of the piston and the pre-obtained effective area of ​​the rod cavity, the effective volume of the rod cavity is obtained;

[0093] Based on the initial piston velocity and the effective area of ​​the rod cavity, the derivative of the effective volume of the rod cavity is obtained;

[0094] The current pressure of the rod cavity is obtained based on the inflow and outflow rates of the rod cavity, the effective volume of the rod cavity, and the derivative of the effective volume of the rod cavity.

[0095] Furthermore, the process of determining the hydraulic cylinder output force included in the second operating condition parameters based on the third functional relationship can specifically include:

[0096] Based on the initial piston displacement and the pre-obtained effective area of ​​the rodless cavity, the effective volume of the rodless cavity is obtained.

[0097] Based on the initial piston velocity and the effective area of ​​the rodless cavity, the derivative of the effective volume of the rodless cavity is obtained;

[0098] The current pressure of the rodless cavity is obtained based on the inflow and outflow rates of the rodless cavity, the effective volume of the rodless cavity, and the derivative of the effective volume of the rodless cavity.

[0099] Based on the initial displacement of the piston and the pre-obtained effective area of ​​the rod cavity, the effective volume of the rod cavity is obtained;

[0100] Based on the initial piston velocity and the effective area of ​​the rod cavity, the derivative of the effective volume of the rod cavity is obtained;

[0101] The current pressure of the rod cavity is obtained based on the inflow and outflow rates of the rod cavity, the effective volume of the rod cavity, and the derivative of the effective volume of the rod cavity.

[0102] Based on the initial piston velocity and the pre-obtained damping coefficient, the frictional resistance during piston movement is obtained;

[0103] The hydraulic cylinder output force is obtained based on the current pressure in the rodless chamber, the current pressure in the rod chamber, and the frictional resistance during piston rod movement.

[0104] Furthermore, the process of determining the current piston displacement included in the second operating condition parameters based on the fourth functional relationship can specifically include:

[0105] Based on the initial piston displacement and the pre-obtained effective area of ​​the rodless cavity, the effective volume of the rodless cavity is obtained.

[0106] Based on the initial piston velocity and the effective area of ​​the rodless cavity, the derivative of the effective volume of the rodless cavity is obtained;

[0107] The current pressure of the rodless cavity is obtained based on the inflow and outflow rates of the rodless cavity, the effective volume of the rodless cavity, and the derivative of the effective volume of the rodless cavity.

[0108] Based on the initial displacement of the piston and the pre-obtained effective area of ​​the rod cavity, the effective volume of the rod cavity is obtained;

[0109] Based on the initial piston velocity and the effective area of ​​the rod cavity, the derivative of the effective volume of the rod cavity is obtained;

[0110] The current pressure of the rod cavity is obtained based on the inflow and outflow rates of the rod cavity, the effective volume of the rod cavity, and the derivative of the effective volume of the rod cavity.

[0111] Based on the initial piston velocity and the pre-obtained damping coefficient, the frictional resistance during piston movement is obtained;

[0112] The hydraulic cylinder output force is obtained based on the current pressure in the rodless chamber, the current pressure in the rod chamber, and the frictional resistance during piston rod movement.

[0113] Based on the output force of the hydraulic cylinder and the mass sum of the piston rod and hydraulic cylinder load obtained in advance, the current acceleration of the piston is obtained;

[0114] The current displacement of the piston is obtained based on the initial displacement and the current acceleration of the piston.

[0115] Furthermore, the process of determining the current piston speed included in the second operating condition parameters based on the fifth functional relationship can specifically include:

[0116] Based on the initial piston displacement and the pre-obtained effective area of ​​the rodless cavity, the effective volume of the rodless cavity is obtained.

[0117] Based on the initial piston velocity and the effective area of ​​the rodless cavity, the derivative of the effective volume of the rodless cavity is obtained;

[0118] The current pressure of the rodless cavity is obtained based on the inflow and outflow rates of the rodless cavity, the effective volume of the rodless cavity, and the derivative of the effective volume of the rodless cavity.

[0119] Based on the initial displacement of the piston and the pre-obtained effective area of ​​the rod cavity, the effective volume of the rod cavity is obtained;

[0120] Based on the initial piston velocity and the effective area of ​​the rod cavity, the derivative of the effective volume of the rod cavity is obtained;

[0121] The current pressure of the rod cavity is obtained based on the inflow and outflow rates of the rod cavity, the effective volume of the rod cavity, and the derivative of the effective volume of the rod cavity.

[0122] Based on the initial piston velocity and the pre-obtained damping coefficient, the frictional resistance during piston movement is obtained;

[0123] The hydraulic cylinder output force is obtained based on the current pressure in the rodless chamber, the current pressure in the rod chamber, and the frictional resistance during piston rod movement.

[0124] Based on the output force of the hydraulic cylinder and the mass sum of the piston rod and hydraulic cylinder load obtained in advance, the current acceleration of the piston is obtained;

[0125] The current piston velocity is obtained based on the piston's initial velocity and current acceleration.

[0126] In an exemplary embodiment, the aforementioned state-space equations may mainly include: the current pressure calculation equation for the rodless chamber, the current pressure calculation equation for the rod chamber, the hydraulic cylinder output force calculation equation, the current piston displacement calculation equation, and the current piston velocity calculation equation.

[0127] Specifically, the aforementioned first functional relationship can be expressed in the form of a mathematical expression through the current pressure calculation equation of the rodless cavity.

[0128] The equation for calculating the current pressure of the rodless cavity is mainly used to characterize the functional relationship between the current pressure of the rodless cavity and the inflow and outflow rates of the rodless cavity, the effective volume of the rodless cavity, and the derivative of the effective volume of the rodless cavity.

[0129] The effective volume of the rodless cavity is obtained based on the initial displacement of the piston and the pre-obtained effective area of ​​the rodless cavity, while the derivative of the effective volume of the rodless cavity is obtained based on the initial velocity of the piston and the pre-obtained effective area of ​​the rodless cavity.

[0130] In an exemplary embodiment, the derivative calculation equation for the current pressure in the rodless cavity can be constructed first, namely:

[0131]

[0132] in, Q represents the derivative of the current pressure in the rodless chamber. head-in Q represents the inflow rate of the rodless cavity. head-out This indicates the outflow rate of the rodless cavity. E represents the derivative of the effective volume of the rodless cavity. p This represents the elastic modulus of the liquid; in this embodiment, E is set as... p =2×10 9 N / Pa 2 V head This indicates the effective volume of the rodless cavity.

[0133] The derivative of the effective volume of the rodless cavity mentioned above The calculation formula is as follows:

[0134]

[0135] in, A represents the derivative of the piston displacement at any time after the dead zone has been corrected. headThis represents the effective area of ​​the rodless cavity.

[0136] After obtaining the derivative calculation equation for the current pressure of the rodless cavity, the current pressure of the rodless cavity can be obtained based on the initial pressure of the rodless cavity and the product of the derivative of the current pressure of the rodless cavity and the time step.

[0137] Specifically, the aforementioned second functional relationship can be expressed in the form of a mathematical expression through the current pressure calculation equation of the rod cavity.

[0138] The equation for calculating the current pressure of the rod cavity is used to characterize the functional relationship between the current pressure of the rod cavity and the inflow and outflow rates of the rod cavity, the effective volume of the rod cavity, and the derivative of the effective volume of the rod cavity;

[0139] The effective volume of the rod cavity is obtained based on the initial displacement of the piston and the pre-obtained effective area of ​​the rod cavity, and the derivative of the effective volume of the rod cavity is obtained based on the initial velocity of the piston and the pre-obtained effective area of ​​the rod cavity.

[0140] In an exemplary embodiment, the derivative calculation equation for the current pressure in the rod cavity can be constructed first, namely:

[0141]

[0142] in, Q represents the derivative of the current pressure in the rod chamber. rod-in Q represents the inflow rate into the rod cavity. rod-out This indicates the outflow rate of the rod cavity. E represents the derivative of the effective volume of the rod cavity. p This represents the elastic modulus of the liquid; in this embodiment, E is set as... p =2×10 9 N / Pa 2 V rod This indicates the effective volume of the rod cavity.

[0143] The formula for calculating the derivative of the effective volume of the rod cavity mentioned above is as follows:

[0144]

[0145] in, A represents the derivative of the piston displacement at any time after the dead zone has been corrected. rod This indicates the effective area of ​​the rod cavity.

[0146] In this embodiment, the following relationship exists:

[0147]

[0148] Among them, v piston This represents the piston speed at any given moment.

[0149] Specifically, the piston displacement y at any time after correcting the dead zone piston The calculation formula is as follows:

[0150] y piston =x piston +x dead (6)

[0151] Where, x piston x represents the initial displacement of the piston. dead This indicates the dead zone length of the piston.

[0152] After obtaining the derivative calculation equation for the current pressure in the rod cavity, the current pressure in the rod cavity can be obtained based on the initial pressure in the rod cavity and the product of the derivative of the current pressure in the rod cavity and the time step.

[0153] It should be noted that the inflow flow rate Q of the rodless cavity in this embodiment is... head-in The outflow rate Q of the rodless cavity head-out Inflow rate Q of the rod cavity rod-in and the outflow rate Q of the rod cavity rod-out With the effective area A of the rodless cavity head and the effective area A of the rod cavity rod The following relationship exists between them:

[0154]

[0155] In this case, given the effective area A of the rodless cavity... head and the effective area A of the rod cavity rod Under the premise that a certain flow parameter can be solved, such as the inflow flow Q based on the rodless cavity. head-in The outflow rate Q of the rod cavity can be calculated. rod-out Based on the outflow rate Q of the rodless cavity head-out The inflow rate Q of the rod cavity can be calculated. rod-in .

[0156] Specifically, the aforementioned third functional relationship can be expressed as a combination of multiple mathematical expressions, based on the calculation equations for the current pressure of the rodless chamber, the current pressure of the rod chamber, and the output force of the hydraulic cylinder.

[0157] In the actual calculation process, the current pressure of the rodless cavity can be calculated first through the current pressure calculation equation of the rodless cavity, and the current pressure of the rod cavity can be calculated through the current pressure calculation equation of the rod cavity. Then, the current pressure of the rodless cavity and the current pressure of the rod cavity are input into the hydraulic cylinder output force calculation equation to further solve for the hydraulic cylinder output force.

[0158] The hydraulic cylinder output force calculation equation is used to characterize the functional relationship between the hydraulic cylinder output force and the current pressure of the rodless chamber, the current pressure of the rod chamber, the pre-obtained effective area of ​​the rodless chamber, the effective area of ​​the rod chamber, the frictional resistance during piston rod movement, and the gravity of the piston rod and the hydraulic cylinder load.

[0159] The frictional resistance during piston movement is based on the initial piston velocity and the pre-obtained damping coefficient.

[0160] In an exemplary embodiment, the equation for calculating the output force of the hydraulic cylinder is as follows:

[0161] F out =(P head A head -P rod A rod )-ff l (8)

[0162] Among them, F out P represents the output force of the hydraulic cylinder, that is, the force exerted by the piston rod. head P represents the current pressure in the rodless chamber. rod A represents the current pressure in the rod chamber. head A represents the effective area of ​​the rodless cavity. rod The effective area of ​​the rod chamber is represented by f, and the frictional resistance during piston rod movement is represented by f. l This represents the sum of the piston rod's own weight and the hydraulic cylinder's load weight, i.e., the sum of the weights of the piston rod and the hydraulic cylinder's load.

[0163] The formula for calculating the frictional resistance f during the piston rod's movement is as follows:

[0164] f = Bv piston (9)

[0165] Where B represents the damping coefficient, and in this embodiment, B = 10. 5 v piston This represents the piston speed at any given moment.

[0166] Specifically, the aforementioned fourth functional relationship can be expressed as a combination of multiple mathematical expressions, including the current pressure calculation equation for the rodless chamber, the current pressure calculation equation for the rod chamber, the hydraulic cylinder output force calculation equation, and the current piston displacement calculation equation.

[0167] In the actual calculation process, the calculation equations for the current pressure of the rodless chamber, the current pressure of the rod chamber, and the hydraulic cylinder output force can be combined to solve for the hydraulic cylinder output force. Then, the current piston acceleration can be calculated based on the hydraulic cylinder output force. The current piston acceleration can be input into the calculation equation for the current piston displacement to obtain the current piston displacement.

[0168] The equation for calculating the current piston displacement is used to characterize the functional relationship between the current piston displacement, the initial piston displacement, and the current piston acceleration.

[0169] The equation for calculating the current piston displacement in this embodiment is:

[0170]

[0171] Where x represents the current displacement of the piston, v0 represents the initial velocity of the piston, t represents the current time, and a represents the current acceleration of the piston.

[0172] The equation for calculating the current piston velocity is used to characterize the functional relationship between the current piston velocity, the initial piston velocity, and the current piston acceleration.

[0173] Specifically, the fifth functional relationship mentioned above can be expressed in the form of a combination of multiple mathematical expressions, which can be used to calculate the current pressure of the rodless chamber, the current pressure of the rod chamber, the hydraulic cylinder output force, and the current piston speed.

[0174] In actual calculations, the equations for calculating the current pressure in the rodless chamber, the current pressure in the rod chamber, and the hydraulic cylinder output force can be combined to solve for the hydraulic cylinder output force. Then, the current piston acceleration can be calculated based on the hydraulic cylinder output force. The current piston acceleration can be input into the equation for calculating the current piston velocity to obtain the current piston velocity.

[0175] The equation for calculating the current piston speed in this embodiment is:

[0176] v = v0 + at (11)

[0177] Where v represents the current velocity of the piston, v0 represents the initial velocity of the piston, t represents the current time, and a represents the current piston acceleration.

[0178] The current piston acceleration is based on the hydraulic cylinder output force and the mass of the piston rod and hydraulic cylinder load obtained in advance.

[0179] The formula for calculating the current acceleration 'a' of the piston is as follows:

[0180]

[0181] Where a represents the current piston acceleration, F out This represents the output force of the hydraulic cylinder, and M represents the mass of the piston rod and the load on the hydraulic cylinder.

[0182] Furthermore, the formulas for calculating the mass and M of the piston rod and hydraulic cylinder load are as follows:

[0183] M = m cylinder +m load (13)

[0184] Where M represents the sum of the masses of the piston rod and the hydraulic cylinder load, m cylinder The mass m of the piston rod is represented by the number of piston rods. load This indicates the mass of the load on the hydraulic cylinder.

[0185] Depend on Figure 2 It can be seen that the digital cylinder model requires the inflow and outflow flow rates of the large and small chambers (i.e., the rodless chamber and the rod chamber) in the initial state as input data. In practical applications, the inflow and outflow flow rates of the rodless chamber and the rod chamber in the initial state can be obtained in the following two ways.

[0186] The first method for obtaining the inflow and outflow rates of the rodless and rod-type chambers in the initial state is as follows:

[0187] Flow sensors are installed on both sides of the rodless and rod chambers of the hydraulic cylinder to detect the inflow and outflow of the rodless and rod chambers in real time, thereby providing input data for the digital cylinder model.

[0188] Although this method also requires the use of sensors, only a flow sensor is needed to provide input data to the digital cylinder model to detect the hydraulic cylinder parameters. Compared with the detection method that uses multiple sensors to detect hydraulic cylinder parameters, fewer sensors are used, the installation and use costs are relatively low, and the later maintenance is relatively more convenient.

[0189] The second method for obtaining the inflow and outflow rates of the rodless and rod-type cavities in the initial state is as follows:

[0190] A joint simulation of the pump system and valve system is performed by establishing the full state equations. The engine speed is controlled by the controller to obtain the initial input data of the pump system (i.e., the initial speed) and the initial input data of the valve system (i.e., the initial opening area of ​​the valve). After iteration, the initial input data of the digital cylinder model (i.e., the inflow and outflow flow rates of the rodless chamber and the rod chamber) are obtained. The subsequent flow parameters can be obtained by iterating through the state equations.

[0191] This method can obtain the inflow and outflow of the rodless and rod chambers without the need for sensors. Compared with the detection method of detecting hydraulic cylinder parameters with multiple sensors, it is less expensive and has higher reliability because there is no detection error caused by sensors.

[0192] Figure 3The closed-loop control process of the hydraulic cylinder involving the pump system, valve system, and controller is shown. In this control process, the controller refers to the controller of the entire hydraulic system. Assuming the engine speed is constant, the second operating condition parameters output from the digital cylinder model include the current pressure of the rodless chamber, the current pressure of the rod chamber, the hydraulic cylinder output force, the current piston displacement, and the current piston speed.

[0193] Figure 3 In the process, the oil inlet flow rate of the large chamber (i.e., the inflow flow rate of the rodless chamber), the oil outlet flow rate of the large chamber (i.e., the outflow flow rate of the rodless chamber), the oil inlet flow rate of the small chamber (i.e., the inflow flow rate of the rod chamber), the oil outlet flow rate of the small chamber (i.e., the outflow flow rate of the rod chamber), the initial displacement of the piston, and the initial velocity of the piston are input into the hydraulic cylinder sub-model 301. After processing by the cylinder sub-model 301, the hydraulic cylinder output force, the pressure of the large chamber (i.e., the current pressure of the rodless chamber), and the pressure of the small chamber (i.e., the current pressure of the rod chamber) are output.

[0194] Then, the hydraulic cylinder output force is input to the dynamic sub-model 302 to obtain the current piston displacement and piston speed. On the one hand, the current piston displacement and piston speed will be used as the new initial piston displacement and initial piston speed to be input to the cylinder sub-model 301 for the next iteration calculation. On the other hand, the current piston displacement and piston speed will also be used as input data for the controller 303. The controller 303 can generate a controller signal based on the input data. The controller signal will participate in the speed control of the pump system 304 and the valve opening area control of the valve system 305.

[0195] Meanwhile, the large chamber pressure and small chamber pressure obtained above will be used as input data for the valve system 305 to participate in the control of the valve system 305. The large chamber oil inlet and large chamber oil outlet output by the valve system 305 will be summed by the summation module 306 and output as the pump system output flow. This output flow will be used as input data to the pump system 304. The pump system 304 obtains pump pressure data based on the output flow. The pump pressure data, along with the large chamber pressure, small chamber pressure, and controller signal, are synchronously input to the valve system 305. After processing by the valve system 305, new large and small chamber oil inlet and outlet data can be output, thereby realizing closed-loop control of the hydraulic cylinder.

[0196] It should be noted that, Figure 3 The cylinder sub-model and dynamics sub-model shown can together constitute the digital cylinder model in this embodiment.

[0197] The method for detecting hydraulic cylinder parameters provided in this implementation is mainly aimed at the hydraulic cylinders of operating machinery. The following uses the hydraulic cylinder of an excavator as an example to explain in detail the implementation process of the method for detecting hydraulic cylinder parameters.

[0198] The excavator contains multiple hydraulic cylinders. Due to the dynamic posture involved, in this embodiment, the hydraulic cylinder is simplified into an external work model with oil entering the rodless chamber and oil exiting the rod chamber. The second working condition parameters output from this model include the current pressure of the rodless chamber, the current pressure of the rod chamber, the hydraulic cylinder output force, the current piston displacement, and the current piston speed.

[0199] The calculation is performed using a time interval of 0 to 1 second, i.e., t0 = 0 s, t1 = 1 s. Let the mass of the hydraulic cylinder load be m. load =10kg, the piston rod's own mass m cylinder =100kg, initial piston position x0=0m, dead zone length x dead =0.01m, after removing the dead zone, the stroke of the hydraulic cylinder is l=1m, and the effective areas of the large and small chambers are A respectively. head =0.1m 2 and A rod =0.05m 2 The initial piston velocity is v0 = 0.1 m / s, and the initial inflow rate into the rodless chamber is Q. head-in (t0)=0.1m 3 / s, the initial pressure of both the large and small chambers is 0Pa. A simplified digital cylinder model is shown below. Figure 4 As shown, Q head-in Q represents the inflow rate of the rodless cavity. rod-out This represents the outflow rate from the rod chamber, and v represents the piston speed.

[0200] The relevant parameters of the hydraulic cylinder in its initial state are as follows:

[0201]

[0202] Where y0 represents the initial displacement of the piston after correcting the dead zone, and A head A represents the effective area of ​​the rodless cavity. rod Q represents the effective area of ​​the rod cavity. head-in (t0) represents the inflow rate of the rodless cavity at time t0, Q rod-out (t0) represents the outflow rate of the rod cavity at time t0. The derivative of the effective volume of the rodless cavity at time t0 is given. V represents the derivative of the effective volume of the rod cavity at time t0. head (t0) represents the effective volume of the rodless cavity at time t0, V rod (t0) represents the effective volume of the rod cavity at time t0. The derivative of the pressure in the rodless cavity at time t0. This represents the derivative of the pressure in the rod cavity at time t0.

[0203] The relevant parameters of the hydraulic cylinder at time t1 are:

[0204]

[0205] Among them, P head (t1) represents the pressure in the rodless cavity at time t1, P rod (t1) represents the pressure in the rod cavity at time t1, F out (t1) represents the output force of the hydraulic cylinder at time t1.

[0206] Therefore, the instantaneous acceleration of the piston rod of the hydraulic cylinder at time t1 is:

[0207]

[0208] Where a(t1) represents the instantaneous acceleration of the piston rod of the hydraulic cylinder at time t1, and M represents the mass of the piston rod and the load of the hydraulic cylinder.

[0209] Based on this instantaneous acceleration, the current displacement and velocity of the piston at time t1 can be obtained further using the above formulas (10) and (11).

[0210] For ease of expression, this embodiment sets the time step Δt to 1 second. In actual applications, the external thrust (i.e., the hydraulic cylinder output force) and acceleration of the piston rod change in real time. As long as the time step is set small enough, the displacement and velocity of the piston rod can be expressed in the form of ordinary differential equations. The ordinary differential expression for the piston displacement is:

[0211]

[0212] The ordinary differential expression for piston velocity is:

[0213]

[0214] The above describes the process of detecting hydraulic cylinder parameters at one time step. The state variable at time t1 is used as the input for the next time step. By repeating this process and performing integration, the piston displacement and piston velocity at any time can be obtained, and the coupling relationship of other parameters in the state space equation can be observed.

[0215] Since the hydraulic cylinder parameter detection method provided in this embodiment can conveniently and reliably obtain a variety of key parameters of the hydraulic cylinder under test, this method can be applied to hydraulic pressure analysis scenarios in hydraulic system simulation, and also to flexible control scenarios in the field of autonomous driving, thus having a wider range of applications.

[0216] Therefore, the hydraulic cylinder parameter detection method provided in this embodiment of the invention has at least the following advantages compared with existing hydraulic cylinder parameter detection methods based on multiple sensors:

[0217] 1. Hydraulic cylinder parameters such as piston displacement, piston speed, pressure in the large and small chambers, and hydraulic cylinder output force can be obtained without installing displacement and pressure sensors on the hydraulic cylinder. This can greatly reduce the cost of hydraulic cylinder parameter detection, reduce the detection error caused by the sensors themselves, and improve the reliability of the obtained hydraulic cylinder parameters.

[0218] 2. The digital cylinder model based on state-space equations can calculate the values ​​of various parameters of the hydraulic cylinder in real time, providing reliable data support for the automatic control of machinery.

[0219] 3. The established digital cylinder model can intuitively reflect the coupling relationship between various parameters of the hydraulic cylinder, providing data basis for R&D personnel to analyze and study.

[0220] The detection device for hydraulic cylinder parameters provided by the present invention will be described below. The detection device for hydraulic cylinder parameters described below and the detection method for hydraulic cylinder parameters described above can be referred to in correspondence.

[0221] Figure 5 This invention illustrates a device for detecting hydraulic cylinder parameters according to an embodiment of the invention. The device includes:

[0222] The acquisition module 501 is used to acquire the first operating parameters of the hydraulic cylinder;

[0223] The processing module 502 is used to input the first working condition parameters into a pre-built digital cylinder model to obtain the second working condition parameters to be detected for the hydraulic cylinder.

[0224] The digital cylinder model is based on the state-space equation of the hydraulic cylinder, which is used to characterize the functional relationship between the second working condition parameter and the first working condition parameter.

[0225] In an exemplary embodiment, the processing module 502 described above can specifically be used for:

[0226] The current pressure of the rodless cavity included in the second operating condition parameters is determined based on the first functional relationship; wherein, the first functional relationship is the relationship between the current pressure of the rodless cavity and the inflow and outflow rates of the rodless cavity, the initial displacement of the piston, and the initial velocity of the piston included in the first operating condition parameters;

[0227] And / or, determine the current pressure of the rod chamber included in the second operating condition parameters based on the second functional relationship; wherein, the second functional relationship is the relationship between the current pressure of the rod chamber and the inflow and outflow rates of the rod chamber, the initial displacement of the piston, and the initial velocity of the piston included in the first operating condition parameters;

[0228] And / or, determine the hydraulic cylinder output force included in the second working condition parameters based on the third functional relationship; wherein, the third functional relationship is the relationship between the hydraulic cylinder output force and the inflow and outflow rates of the rodless chamber, the inflow and outflow rates of the rod chamber, the initial piston displacement, and the initial piston velocity included in the first working condition parameters;

[0229] And / or, determine the current piston displacement included in the second operating condition parameters based on the fourth functional relationship; wherein, the fourth functional relationship is the relationship between the current piston displacement and the inflow and outflow rates of the rodless cavity, the inflow and outflow rates of the rod cavity, the initial piston displacement, and the initial piston velocity included in the first operating condition parameters;

[0230] And / or, determine the current piston speed included in the second operating condition parameters based on the fifth functional relationship; wherein, the fifth functional relationship is the relationship between the current piston speed and the inflow and outflow rates of the rodless cavity, the inflow and outflow rates of the rod cavity, the initial piston displacement, and the initial piston speed included in the first operating condition parameters.

[0231] Furthermore, the aforementioned processing module 502 can specifically determine the current pressure of the rodless cavity included in the second operating condition parameters based on the first functional relationship in the following manner:

[0232] Based on the initial piston displacement and the pre-obtained effective area of ​​the rodless cavity, the effective volume of the rodless cavity is obtained.

[0233] Based on the initial piston velocity and the effective area of ​​the rodless cavity, the derivative of the effective volume of the rodless cavity is obtained;

[0234] The current pressure of the rodless cavity is obtained based on the inflow and outflow rates of the rodless cavity, the effective volume of the rodless cavity, and the derivative of the effective volume of the rodless cavity.

[0235] Furthermore, the aforementioned processing module 502 can specifically determine the current pressure of the rod cavity included in the second operating condition parameters based on the second functional relationship in the following manner:

[0236] Based on the initial displacement of the piston and the pre-obtained effective area of ​​the rod cavity, the effective volume of the rod cavity is obtained;

[0237] Based on the initial piston velocity and the effective area of ​​the rod cavity, the derivative of the effective volume of the rod cavity is obtained;

[0238] The current pressure of the rod cavity is obtained based on the inflow and outflow rates of the rod cavity, the effective volume of the rod cavity, and the derivative of the effective volume of the rod cavity.

[0239] Furthermore, the aforementioned processing module 502 can specifically determine the hydraulic cylinder output force included in the second working condition parameters based on the third functional relationship in the following manner:

[0240] Based on the initial piston displacement and the pre-obtained effective area of ​​the rodless cavity, the effective volume of the rodless cavity is obtained.

[0241] Based on the initial piston velocity and the effective area of ​​the rodless cavity, the derivative of the effective volume of the rodless cavity is obtained;

[0242] The current pressure of the rodless cavity is obtained based on the inflow and outflow rates of the rodless cavity, the effective volume of the rodless cavity, and the derivative of the effective volume of the rodless cavity.

[0243] Based on the initial displacement of the piston and the pre-obtained effective area of ​​the rod cavity, the effective volume of the rod cavity is obtained;

[0244] Based on the initial piston velocity and the effective area of ​​the rod cavity, the derivative of the effective volume of the rod cavity is obtained;

[0245] The current pressure of the rod cavity is obtained based on the inflow and outflow rates of the rod cavity, the effective volume of the rod cavity, and the derivative of the effective volume of the rod cavity.

[0246] Based on the initial piston velocity and the pre-obtained damping coefficient, the frictional resistance during piston movement is obtained;

[0247] The hydraulic cylinder output force is obtained based on the current pressure in the rodless chamber, the current pressure in the rod chamber, and the frictional resistance during piston rod movement.

[0248] Furthermore, the aforementioned processing module 502 can specifically determine the current piston displacement included in the second operating condition parameters based on the fourth functional relationship in the following manner:

[0249] Based on the initial piston displacement and the pre-obtained effective area of ​​the rodless cavity, the effective volume of the rodless cavity is obtained.

[0250] Based on the initial piston velocity and the effective area of ​​the rodless cavity, the derivative of the effective volume of the rodless cavity is obtained;

[0251] The current pressure of the rodless cavity is obtained based on the inflow and outflow rates of the rodless cavity, the effective volume of the rodless cavity, and the derivative of the effective volume of the rodless cavity.

[0252] Based on the initial displacement of the piston and the pre-obtained effective area of ​​the rod cavity, the effective volume of the rod cavity is obtained;

[0253] Based on the initial piston velocity and the effective area of ​​the rod cavity, the derivative of the effective volume of the rod cavity is obtained;

[0254] The current pressure of the rod cavity is obtained based on the inflow and outflow rates of the rod cavity, the effective volume of the rod cavity, and the derivative of the effective volume of the rod cavity.

[0255] Based on the initial piston velocity and the pre-obtained damping coefficient, the frictional resistance during piston movement is obtained;

[0256] The hydraulic cylinder output force is obtained based on the current pressure in the rodless chamber, the current pressure in the rod chamber, and the frictional resistance during piston rod movement.

[0257] Based on the output force of the hydraulic cylinder and the mass sum of the piston rod and hydraulic cylinder load obtained in advance, the current acceleration of the piston is obtained;

[0258] The current displacement of the piston is obtained based on the initial displacement and the current acceleration of the piston.

[0259] Furthermore, the aforementioned processing module 502 can specifically determine the current piston speed included in the second operating condition parameters based on the fifth functional relationship in the following manner:

[0260] Based on the initial piston displacement and the pre-obtained effective area of ​​the rodless cavity, the effective volume of the rodless cavity is obtained.

[0261] Based on the initial piston velocity and the effective area of ​​the rodless cavity, the derivative of the effective volume of the rodless cavity is obtained;

[0262] The current pressure of the rodless cavity is obtained based on the inflow and outflow rates of the rodless cavity, the effective volume of the rodless cavity, and the derivative of the effective volume of the rodless cavity.

[0263] Based on the initial displacement of the piston and the pre-obtained effective area of ​​the rod cavity, the effective volume of the rod cavity is obtained;

[0264] Based on the initial piston velocity and the effective area of ​​the rod cavity, the derivative of the effective volume of the rod cavity is obtained;

[0265] The current pressure of the rod cavity is obtained based on the inflow and outflow rates of the rod cavity, the effective volume of the rod cavity, and the derivative of the effective volume of the rod cavity.

[0266] Based on the initial piston velocity and the pre-obtained damping coefficient, the frictional resistance during piston movement is obtained;

[0267] The hydraulic cylinder output force is obtained based on the current pressure in the rodless chamber, the current pressure in the rod chamber, and the frictional resistance during piston rod movement.

[0268] Based on the output force of the hydraulic cylinder and the mass sum of the piston rod and hydraulic cylinder load obtained in advance, the current acceleration of the piston is obtained;

[0269] The current piston velocity is obtained based on the piston's initial velocity and current acceleration.

[0270] Therefore, the hydraulic cylinder parameter detection device provided in this embodiment of the invention can obtain real-time key hydraulic cylinder parameters such as large and small chamber pressure, hydraulic cylinder output force, piston displacement and piston speed through a digital cylinder model. This can reduce or even eliminate the use of multiple sensors, thereby reducing costs and improving the reliability of hydraulic cylinder parameters.

[0271] Figure 6 This invention illustrates a control method for a work machine provided in an embodiment of the invention. The method includes:

[0272] Step 601: Obtain the second operating parameters of the hydraulic cylinder using the above-mentioned method for detecting hydraulic cylinder parameters;

[0273] Step 602: Control the operation of the machine based on the second working condition parameters.

[0274] Understandably, based on the obtained second working condition parameters of the hydraulic cylinder, the controller of the operating machinery can be assisted in generating corresponding control signals. For example, when the operating machinery is an excavator, the current piston displacement and current piston speed in the second working condition parameters can be used to further generate a handle opening control signal to control the excavator's working device to perform corresponding operating actions.

[0275] Furthermore, in the control method for the working machinery provided in the embodiments of the present invention, since the above-mentioned hydraulic cylinder parameter detection method is used, it also has the various advantages of the above-mentioned hydraulic cylinder parameter detection method.

[0276] Meanwhile, the control method for the operating machinery can be an automatic control scheme for the operating machinery during actual construction, or a simulation control scheme for the operating machinery during joint simulation. For example, the control method for the operating machinery can be applied to the simulation control process of a hydraulic simulation platform.

[0277] Traditional hydraulic simulation platforms encapsulate the mathematical model inside the hydraulic cylinder module to lower the barrier to entry. Simulators can only rely on experience or feedback from measured sensors for analysis. The digital cylinder model provided by this invention can intuitively reflect the coupling relationship between the internal parameters of the hydraulic cylinder, providing more reliable data for the hydraulic simulation platform.

[0278] In addition, this embodiment of the invention also provides a working machine that uses the above-described control method for working machines.

[0279] It is understandable that the aforementioned operating machinery can be construction machinery such as excavators and cranes. By applying the control methods of the aforementioned operating machinery, the control accuracy of the automatic driving control system in the operating machinery can be improved, and data support can be provided for the realization of unmanned driving of the operating machinery.

[0280] Figure 7 An example is a schematic diagram of the physical structure of an electronic device, such as... Figure 7 As shown, the electronic device may include a processor 701, a communication interface 702, a memory 703, and a communication bus 704. The processor 701, communication interface 702, and memory 703 communicate with each other via the communication bus 704. The processor 701 can call logical instructions in the memory 703 to execute a method for detecting hydraulic cylinder parameters. This method includes: acquiring first operating parameters of the hydraulic cylinder; inputting the first operating parameters into a pre-constructed digital cylinder model to obtain second operating parameters to be detected for the hydraulic cylinder; the digital cylinder model is established based on the state-space equation of the hydraulic cylinder, and the state-space equation is used to characterize the functional relationship between the second operating parameters and the first operating parameters.

[0281] Furthermore, the logical instructions in the aforementioned memory 703 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, essentially, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0282] On the other hand, the present invention also provides a computer program product, the computer program product including a computer program stored on a non-transitory computer-readable storage medium, the computer program including program instructions, when the program instructions are executed by a computer, the computer is able to execute the hydraulic cylinder parameter detection method provided by the above methods, the method including: obtaining a first operating condition parameter of the hydraulic cylinder; inputting the first operating condition parameter into a pre-constructed digital cylinder model to obtain a second operating condition parameter of the hydraulic cylinder to be detected; the digital cylinder model is established based on the state space equation of the hydraulic cylinder, the state space equation is used to characterize the functional relationship between the second operating condition parameter and the first operating condition parameter.

[0283] In another aspect, the present invention also provides a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the above-described methods for detecting hydraulic cylinder parameters. The method includes: acquiring first operating parameters of the hydraulic cylinder; inputting the first operating parameters into a pre-constructed digital cylinder model to obtain second operating parameters of the hydraulic cylinder to be detected; wherein the digital cylinder model is established based on the state-space equation of the hydraulic cylinder, and the state-space equation is used to characterize the functional relationship between the second operating parameters and the first operating parameters.

[0284] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0285] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for detecting parameters of a hydraulic cylinder, characterized in that, include: Obtain the first operating parameters of the hydraulic cylinder; The first working condition parameters are input into a pre-built digital cylinder model to obtain the second working condition parameters to be detected for the hydraulic cylinder. The process of obtaining the second operating condition parameter to be tested for the hydraulic cylinder includes: The current pressure of the rodless chamber included in the second operating condition parameters is determined based on a first functional relationship; wherein, the first functional relationship is the relationship between the current pressure of the rodless chamber and the inflow and outflow rates of the rodless chamber, the initial piston displacement, and the initial piston velocity included in the first operating condition parameters; the determination of the current pressure of the rodless chamber included in the second operating condition parameters based on the first functional relationship includes: Based on the initial displacement of the piston and the pre-obtained effective area of ​​the rodless cavity, the effective volume of the rodless cavity is obtained; Based on the initial velocity of the piston and the effective area of ​​the rodless cavity, the derivative of the effective volume of the rodless cavity is obtained; The current pressure of the rodless cavity is obtained based on the inflow and outflow rates of the rodless cavity, the effective volume of the rodless cavity, and the derivative of the effective volume of the rodless cavity. The digital cylinder model is established based on the state-space equation of the hydraulic cylinder, which is used to characterize the functional relationship between the second working condition parameter and the first working condition parameter.

2. The method for detecting hydraulic cylinder parameters according to claim 1, characterized in that, The process of obtaining the second operating condition parameter to be tested for the hydraulic cylinder includes: The current pressure of the rod chamber included in the second operating condition parameters is determined based on the second functional relationship; wherein, the second functional relationship is the relationship between the current pressure of the rod chamber and the inflow and outflow rates of the rod chamber, the initial displacement of the piston, and the initial velocity of the piston included in the first operating condition parameters; And / or, the hydraulic cylinder output force included in the second operating condition parameters is determined based on a third functional relationship; wherein, the third functional relationship is the relationship between the hydraulic cylinder output force and the inflow and outflow rates of the rodless chamber, the inflow and outflow rates of the rod chamber, the initial piston displacement, and the initial piston velocity included in the first operating condition parameters; And / or, determine the current piston displacement included in the second operating condition parameters based on the fourth functional relationship; wherein, the fourth functional relationship is the relationship between the current piston displacement and the inflow and outflow rates of the rodless cavity, the inflow and outflow rates of the rod cavity, the initial piston displacement, and the initial piston velocity included in the first operating condition parameters; And / or, determine the current piston speed included in the second operating condition parameters based on the fifth functional relationship; wherein, the fifth functional relationship is the relationship between the current piston speed and the inflow and outflow rates of the rodless chamber, the inflow and outflow rates of the rod chamber, the initial piston displacement, and the initial piston speed included in the first operating condition parameters.

3. The method for detecting hydraulic cylinder parameters according to claim 2, characterized in that, The determination of the current pressure of the rod chamber included in the second operating condition parameters based on the second functional relationship includes: Based on the initial displacement of the piston and the pre-obtained effective area of ​​the rod cavity, the effective volume of the rod cavity is obtained. Based on the initial velocity of the piston and the effective area of ​​the rod chamber, the derivative of the effective volume of the rod chamber is obtained; The current pressure of the rod cavity is obtained based on the inflow and outflow rates of the rod cavity, the effective volume of the rod cavity, and the derivative of the effective volume of the rod cavity.

4. The method for detecting hydraulic cylinder parameters according to claim 2, characterized in that, The determination of the hydraulic cylinder output force included in the second working condition parameters based on the third functional relationship includes: Based on the initial displacement of the piston and the pre-obtained effective area of ​​the rodless cavity, the effective volume of the rodless cavity is obtained; Based on the initial velocity of the piston and the effective area of ​​the rodless cavity, the derivative of the effective volume of the rodless cavity is obtained; The current pressure of the rodless cavity is obtained based on the inflow and outflow rates of the rodless cavity, the effective volume of the rodless cavity, and the derivative of the effective volume of the rodless cavity. Based on the initial displacement of the piston and the pre-obtained effective area of ​​the rod cavity, the effective volume of the rod cavity is obtained. Based on the initial velocity of the piston and the effective area of ​​the rod chamber, the derivative of the effective volume of the rod chamber is obtained; The current pressure of the rod cavity is obtained based on the inflow and outflow rates of the rod cavity, the effective volume of the rod cavity, and the derivative of the effective volume of the rod cavity. Based on the initial piston velocity and the pre-obtained damping coefficient, the frictional resistance during piston movement is obtained; The output force of the hydraulic cylinder is obtained based on the current pressure of the rodless chamber, the current pressure of the rod chamber, and the frictional resistance during piston rod movement.

5. The method for detecting hydraulic cylinder parameters according to claim 2, characterized in that, The determination of the current piston displacement included in the second operating condition parameters based on the fourth functional relationship includes: Based on the initial displacement of the piston and the pre-obtained effective area of ​​the rodless cavity, the effective volume of the rodless cavity is obtained; Based on the initial velocity of the piston and the effective area of ​​the rodless cavity, the derivative of the effective volume of the rodless cavity is obtained; The current pressure of the rodless cavity is obtained based on the inflow and outflow rates of the rodless cavity, the effective volume of the rodless cavity, and the derivative of the effective volume of the rodless cavity. Based on the initial displacement of the piston and the pre-obtained effective area of ​​the rod cavity, the effective volume of the rod cavity is obtained. Based on the initial velocity of the piston and the effective area of ​​the rod chamber, the derivative of the effective volume of the rod chamber is obtained; The current pressure of the rod cavity is obtained based on the inflow and outflow rates of the rod cavity, the effective volume of the rod cavity, and the derivative of the effective volume of the rod cavity. Based on the initial piston velocity and the pre-obtained damping coefficient, the frictional resistance during piston movement is obtained; The hydraulic cylinder output force is obtained based on the current pressure of the rodless chamber, the current pressure of the rod chamber, and the frictional resistance during piston rod movement. Based on the output force of the hydraulic cylinder and the mass sum of the piston rod and hydraulic cylinder load obtained in advance, the current acceleration of the piston is obtained; The current displacement of the piston is obtained based on the initial displacement of the piston and the current acceleration of the piston.

6. The method for detecting hydraulic cylinder parameters according to claim 2, characterized in that, The determination of the current piston speed included in the second operating condition parameters based on the fifth functional relationship includes: Based on the initial displacement of the piston and the pre-obtained effective area of ​​the rodless cavity, the effective volume of the rodless cavity is obtained; Based on the initial velocity of the piston and the effective area of ​​the rodless cavity, the derivative of the effective volume of the rodless cavity is obtained; The current pressure of the rodless cavity is obtained based on the inflow and outflow rates of the rodless cavity, the effective volume of the rodless cavity, and the derivative of the effective volume of the rodless cavity. Based on the initial displacement of the piston and the pre-obtained effective area of ​​the rod cavity, the effective volume of the rod cavity is obtained. Based on the initial velocity of the piston and the effective area of ​​the rod chamber, the derivative of the effective volume of the rod chamber is obtained; The current pressure of the rod cavity is obtained based on the inflow and outflow rates of the rod cavity, the effective volume of the rod cavity, and the derivative of the effective volume of the rod cavity. Based on the initial piston velocity and the pre-obtained damping coefficient, the frictional resistance during piston movement is obtained; The hydraulic cylinder output force is obtained based on the current pressure of the rodless chamber, the current pressure of the rod chamber, and the frictional resistance during piston rod movement. Based on the output force of the hydraulic cylinder and the mass sum of the piston rod and hydraulic cylinder load obtained in advance, the current acceleration of the piston is obtained; The current velocity of the piston is obtained based on the initial velocity of the piston and the current acceleration of the piston.

7. A device for detecting parameters of a hydraulic cylinder, characterized in that, include: The acquisition module is used to acquire the first operating parameters of the hydraulic cylinder; The processing module is used to input the first working condition parameters into a pre-built digital cylinder model to obtain the second working condition parameters to be detected for the hydraulic cylinder. The process of obtaining the second operating condition parameter to be tested for the hydraulic cylinder includes: The current pressure of the rodless chamber included in the second operating condition parameters is determined based on a first functional relationship; wherein, the first functional relationship is the relationship between the current pressure of the rodless chamber and the inflow and outflow rates of the rodless chamber, the initial piston displacement, and the initial piston velocity included in the first operating condition parameters; the determination of the current pressure of the rodless chamber included in the second operating condition parameters based on the first functional relationship includes: Based on the initial displacement of the piston and the pre-obtained effective area of ​​the rodless cavity, the effective volume of the rodless cavity is obtained; Based on the initial velocity of the piston and the effective area of ​​the rodless cavity, the derivative of the effective volume of the rodless cavity is obtained; The current pressure of the rodless cavity is obtained based on the inflow and outflow rates of the rodless cavity, the effective volume of the rodless cavity, and the derivative of the effective volume of the rodless cavity. The digital cylinder model is established based on the state-space equation of the hydraulic cylinder, which is used to characterize the functional relationship between the second working condition parameter and the first working condition parameter.

8. A control method for a work machinery, characterized in that, include: The second operating parameters of the hydraulic cylinder are obtained by the detection method of the hydraulic cylinder parameters as described in any one of claims 1 to 6. The operating actions of the machinery are controlled based on the second operating condition parameters.

9. A type of operating machinery, characterized in that, The operating machinery uses the operating machinery control method as described in claim 8.

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