Dynamic control model and real-time adjustment method of shield machine's small-angle wall grinding posture

Abstract

The application relates to the field of automatic control of shield construction, and discloses a dynamic control model and a real-time adjustment method for a small-angle wall grinding posture of a shield, wherein the control model comprises: a posture modeling module, a trajectory target construction module, a trajectory constraint configuration module, a control trajectory generation module and an instruction output module; the posture modeling module comprises: a posture angle analysis unit, which is used for collecting space posture information of a shield machine in a construction coordinate system and converting the information into a representation form of a pitch angle and a yaw angle; and a posture angle function generation unit, which is used for establishing a continuous expression model of a two-dimensional posture angle vector based on a time sequence; the trajectory target construction module comprises: a kinetic energy item definition unit, which is used for calculating an angular velocity according to a derivative of a two-dimensional posture angle vector with respect to time. Through the construction of a posture trajectory optimization model and an instruction output mapping mechanism, the application realizes a high-precision, low-delay and feedback shield posture dynamic adjustment control effect.

Description

Technical Field

[0001] The present invention relates to the field of shield construction automation control, in particular to a shield small-angle wall grinding posture dynamic control model and a real-time adjustment method. Background Art

[0002] With the continuous expansion of urban infrastructure, the development and utilization of underground space has become increasingly important. Shield tunneling, due to its high efficiency and minimal disturbance, has been widely used in projects such as subways, tunnels, and pipeline corridors. However, when tunneling in complex geological conditions, attitude control is crucial. Inaccurate attitude control can not only lead to deviations in the propulsion direction but also create risks such as abnormal structural stress and instability in the tunnel face.

[0003] In existing technologies, shield machine attitude control mostly relies on static planning and rule-based adjustment strategies. By combining preset control paths with some sensor feedback, the system can achieve attitude correction within a certain range. Furthermore, some solutions based on classic PID control have demonstrated strong stability in practical applications, maintaining relatively stable operation in homogeneous strata or linear tunneling conditions. Some methods also incorporate limited optimization algorithms to adjust control strategy parameters, achieving relatively ideal control responses under specific conditions.

[0004] However, there are still some shortcomings in the existing technology. First, the trajectory design is mostly generated by static or linear models, which are rigid and lack flexibility when facing heterogeneous strata. Secondly, the conversion process from trajectory to control instructions is often unsystematic, with high coupling between interfaces, prone to mismatch and delay. Furthermore, the existing system lacks an efficient feedback mechanism and cannot adjust the control strategy based on the real-time posture of the shield machine. It can only blindly execute the preset trajectory and adjust it only when problems arise. In addition, the accuracy is insufficient. Although the trajectory points are calculated, they are not accurate after being converted into execution instructions, resulting in significant deviations in the control results. Summary of the Invention

[0005] In response to the shortcomings of the existing technology, the present invention provides a dynamic control model and real-time adjustment method for the shield machine's small-angle wall grinding posture, which solves the problems in the existing technology of lack of real-time attitude trajectory control, irregular control instruction conversion, weak feedback mechanism and insufficient execution accuracy under complex working conditions.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solutions: a shield small-angle wall grinding posture dynamic control model, including:

[0007] A posture modeling module is used to establish a two-dimensional posture angle vector model consisting of a pitch angle and a yaw angle based on the motion state of the shield machine in space, wherein the posture angle vector is a function of time;

[0008] A trajectory target construction module constructs a trajectory optimization objective function including an angular velocity-related kinetic energy term and an attitude angle-related position potential energy term based on the attitude angle vector model;

[0009] A trajectory constraint configuration module, used to configure the boundary conditions of the trajectory optimization objective function and the constraint conditions of the second-order derivative of the attitude angle;

[0010] A control trajectory generation module is used to establish a trajectory control model that describes the time evolution of the attitude angle according to the optimization objective function and its constraints, and obtain a discrete solution of the corresponding trajectory;

[0011] The instruction output module is used to convert the posture trajectory data generated by the trajectory control model into posture adjustment control instructions for the shield propulsion equipment.

[0012] Preferably, the posture modeling module includes:

[0013] The attitude angle analysis unit is used to collect the spatial attitude information of the shield machine in the construction coordinate system and convert the information into the representation of pitch angle and yaw angle;

[0014] The attitude angle function generation unit is used to establish a continuous expression model of a two-dimensional attitude angle vector based on a time series.

[0015] Preferably, the trajectory target construction module includes:

[0016] The kinetic energy term definition unit is used to calculate the angular velocity based on the derivative of the two-dimensional attitude angle vector with respect to time, and is constructed in the form of;

[0017] ;

[0018] Where, Represents the attitude angular velocity vector; is the attitude inertia matrix; Indicates time attitude kinetic energy; is a constant coefficient; Represents the transposed form of the attitude angular velocity vector;

[0019] A potential energy term definition unit is used to construct a potential energy function for reflecting the tendency of wall contact caused by the shield attitude angle exceeding a critical value, wherein the function is a nonlinear positive definite form with respect to the attitude angle;

[0020] The trajectory target assembly unit is used to combine the kinetic energy term and the potential energy term into a trajectory optimization objective function for subsequent modules to call.

[0021] Preferably, the potential energy term definition unit includes:

[0022] An attitude sensitive direction setting unit is used to set a two-dimensional sensitive vector representing the main direction of shield attitude deviation;

[0023] A critical angle threshold setting unit, used to configure a critical angle at which the attitude angle exceeds the wall contact limit;

[0024] The potential energy function generating unit is used to generate a contact risk potential energy term, where the potential energy term is a nonlinear function of the attitude angle within the limit interval and depends on the difference deviation in a square form.

[0025] Preferably, the trajectory constraint configuration module includes:

[0026] Boundary constraint setting unit, used to set the starting and ending boundary values ​​of the attitude angle to ensure that the starting and ending points of the trajectory are consistent with the target attitude of the shield;

[0027] The smoothness constraint setting unit is used to impose an acceleration intensity constraint on the attitude angle trajectory, and the constraint satisfies the following integral relationship:

[0028] ;

[0029] Where, is the attitude angular acceleration; is the preset smoothness threshold; Indicates the upper limit of the control time domain; Represents the definite integral symbol;

[0030] The constraint encoding unit is used to convert the set boundary conditions and smoothness constraints into a unified constraint structure data format for the trajectory control model to call.

[0031] Preferably, the constraint coding unit includes:

[0032] Boundary value structure encapsulation unit, used to organize the boundary values ​​of the starting and ending attitude angles into a data structure with time tags;

[0033] The acceleration limit encapsulation unit is used to uniformly encapsulate the integral upper limit value contained in the smoothness constraint and the corresponding acceleration variable identifier;

[0034] The constraint set formatting unit is used to combine and standardize the formats of the above-mentioned multiple constraint structures according to a data format recognizable by the control trajectory generation module.

[0035] Preferably, the control trajectory generation module includes:

[0036] The trajectory equation construction unit is used to construct the trajectory control equation based on the trajectory optimization objective function and its constraints. The control equation is a fourth-order differential equation of the following form:

[0037] ;

[0038] Where, is the contact potential energy function; and is the control coefficient; is a symmetric positive definite attitude inertia matrix; is the two-dimensional attitude angle vector; is the attitude angular acceleration; express Function attitude angle vector The gradient of the attitude angle; the fourth-order derivative, High-order smoothness control that represents the attitude angle's temporal variation trend;

[0039] A discrete solution unit, configured to perform pseudo-spectral discretization of the trajectory control equation in the time domain and solve the equation using a numerical optimization method to obtain an optimal posture trajectory;

[0040] The trajectory cache unit is used to store the discrete results of the optimal trajectory and provide an interface for the instruction output module to read.

[0041] Preferably, the discrete solution unit includes:

[0042] A time node generation unit, based on a discrete time node set of pseudo-spectral density distribution;

[0043] The derivative matrix construction unit is used to generate a pseudo-spectral derivative matrix corresponding to each order of derivatives based on a set of time nodes.

[0044] Preferably, the instruction output module includes:

[0045] The posture mapping unit is used to map the target value of the optimal posture trajectory at each moment into the control value of the corresponding shield propulsion cylinder;

[0046] A control format conversion unit, used to convert the attitude target value into the voltage, force control or displacement control instruction format required by the propulsion control system;

[0047] The communication interface unit is used to periodically send the control instructions to the shield propulsion main control system through the industrial control protocol to achieve continuous execution.

[0048] The present invention also provides a method for real-time adjustment of dynamic control of shield small-angle wall grinding posture, comprising the following steps:

[0049] S1. Based on the current attitude angle information obtained during the shield machine's advancement, extract the two-dimensional attitude angle vector including the pitch angle and the yaw angle, and compare it with the set target attitude angle vector to determine the initial state difference of the attitude adjustment;

[0050] S2. Based on the initial state difference, construct a trajectory optimization objective function including an angular velocity-related kinetic energy term and an attitude angle-related potential energy term as a function input for control trajectory derivation;

[0051] S3. Based on the constructed trajectory optimization objective function, combined with the set boundary conditions and acceleration smoothness constraints, a high-order differential control equation describing the attitude trajectory evolution law is established;

[0052] S4. performing time-domain discretization processing on the high-order differential control equation, calling a numerical solver to obtain a corresponding discrete attitude trajectory solution, and simultaneously mapping the trajectory solution into a control instruction format recognizable by the shield propulsion system;

[0053] S5. Inject the control instruction format into the shield main control system periodically, and synchronously collect the current attitude angle information of the shield machine. Re-trigger the iterative process of step S2 to step S4 based on the deviation between the latest feedback attitude and the original target attitude to complete the dynamic update of the attitude trajectory.

[0054] The present invention provides a dynamic control model and real-time adjustment method for shield machine small-angle wall grinding posture. It has the following beneficial effects:

[0055] 1. This invention utilizes a posture control trajectory generation technology based on an optimization objective function, achieving the technical effect of precisely controlling the shield machine's posture adjustment. Compared to existing posture adjustment solutions that rely on traditional fixed path planning or crude empirical rules, this invention dynamically adjusts the trajectory based on real-time optimization objectives, making posture adjustment more flexible and precise, improving operational efficiency and system response speed.

[0056] 2. This invention introduces a pseudospectral method to discretize trajectories, effectively improving the accuracy and stability of trajectory control. Compared to traditional numerical optimization methods or simple interpolation methods used in the prior art, this reduces system instability caused by computational errors and improves the device's performance under complex operating conditions.

[0057] 3. This invention establishes an efficient data transmission and control conversion channel between the control trajectory generation module and the command output module, ensuring seamless integration of trajectory data with the shield equipment control system. Unlike the complex interfaces and protocol mismatches common in existing technologies, this invention's modular design simplifies the control command transmission process, reduces data latency, and improves control response speed and system interoperability.

[0058] 4. This invention provides a real-time feedback mechanism, using the shield machine's real-time posture data to modify control instructions, further optimizing control effectiveness. Compared to existing systems that lack real-time feedback and adjustment, this invention can capture posture deviations in real time and make adaptive adjustments, enabling the system to respond more quickly and accurately to unexpected operating conditions, significantly enhancing the equipment's adaptability and reliability in dynamic environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 This is a control model architecture diagram of the present invention;

[0060] Figure 2 This is a framework diagram of the posture modeling module of the present invention;

[0061] Figure 3 A diagram of the trajectory target building module framework of the present invention;

[0062] Figure 4 This is a framework diagram of the trajectory constraint configuration module of the present invention;

[0063] Figure 5 A control trajectory generation module framework diagram for the present invention;

[0064] Figure 6 This is a framework diagram of the instruction output module of the present invention;

[0065] Figure 7 Schematic diagram of the adjustment method of the present invention. DETAILED DESCRIPTION

[0066] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the present specification. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0067] Please see the attached Figure 1 -Attached Figure 6 The embodiment of the present invention provides a dynamic control model for shield small-angle wall grinding posture, including:

[0068] A posture modeling module is used to establish a two-dimensional posture angle vector model consisting of a pitch angle and a yaw angle based on the motion state of the shield machine in space, wherein the posture angle vector is a function of time;

[0069] To ensure the shield machine maintains its designed attitude range during advancement and avoid minor deviations that could cause wall interference or control instability, it's necessary to establish a time-evolving attitude angle modeling structure at the system level. As the input source for the overall control architecture, the attitude modeling module directly determines the modeling accuracy and response boundaries of trajectory control.

[0070] This module maintains data logic continuity with the subsequent trajectory target construction module. The attitude angle function it outputs serves as the core variable in the kinetic and potential energy terms of the optimization objective function, participating in the control trajectory solution. Therefore, attitude modeling must ensure temporal consistency, function differentiability, and the accuracy of the physical meaning of the angles.

[0071] In this embodiment, the posture modeling module mainly includes two core sub-units: a posture angle analysis unit and a posture angle function generation unit.

[0072] Generally, the spatial motion state of a shield machine is described by six degrees of freedom: three-dimensional position and three-dimensional attitude. In this paper, considering the actual needs of shield machines in small-angle wall grinding control, only the pitch angle and yaw angle are selected as control variables, and the attitude is modeled in the form of a two-dimensional angle vector. The specific definition is as follows:

[0073] ;

[0074] Where, is the two-dimensional attitude angle vector; Indicates the pitch angle; represents the yaw angle, which is defined as the rotation angle of the front end of the shield machine around the vertical axis; is the time variable.

[0075] In one possible implementation, the attitude angle analysis unit communicates data with the inertial measurement unit (IMU) installed at the front end of the shield machine, collects raw spatial angular velocity information including accelerometers and gyroscopes, and uses integral operations to restore the angle trajectory.

[0076] Specifically, in some embodiments, the Euler angle solution can be performed on the current rotation matrix of the shield machine to obtain the pitch and yaw angle values. This process includes mapping the rotation matrix to the Euler angle:

[0077] ;

[0078] Where, Indicates the pitch angle; represents the yaw angle, which is defined as the rotation angle of the front end of the shield machine around the vertical axis; is the time variable; Indicates at time In the rotation matrix, the element in the third row and first column represents the projection component of the Z axis in the initial X direction, which is used to calculate the pitch angle; Indicates at time In the rotation matrix, the element in the second row and first column represents the projection component of the Y axis in the initial X direction; Indicates at time In the rotation matrix, the element in the first row and first column represents the projection component of the X axis in the initial X direction.

[0079] As an option, when the attitude angle is provided by an external measurement system (such as a total station), the measured three-dimensional coordinate points of the shield leading edge position can be subjected to multi-frame registration, and the pitch and yaw angles can be inverted by fitting their tangential change trend along the propulsion direction.

[0080] The task of the attitude angle function generation unit is to construct a time-continuous expression for the above discrete angle data. In order to meet the requirements of trajectory optimization and derivative operation, in the present invention, the function is usually constructed using cubic spline interpolation:

[0081] ;

[0082] Where, is the two-dimensional attitude angle vector; is the interpolation coefficient vector; is a B-spline or other form of basis function; Indicates the number of interpolation nodes.

[0083] In some embodiments, in order to satisfy the structural compatibility of subsequent pseudo-spectral discrete processing, the basis function may also be constructed using Chebyshev polynomials or Lagrange basis functions, so that the trajectory derivative matrix structure is directly connected to the pseudo-spectral derivative matrix.

[0084] In order to further improve the stability of the control response, the present invention imposes constraints on the continuity and differentiability of the attitude angle function: at least in the continuous space, it has the derivative closure property. Its first-order derivative and second-order derivative satisfy:

[0085] ;

[0086] Where, Represents the attitude angular velocity vector; is the attitude angular acceleration; is the two-dimensional attitude angle vector; is the first-order time derivative operator; is the second-order time derivative operator.

[0087] As a specific implementation form, during the trajectory initialization stage, linear interpolation or multi-segment continuous polynomials can also be used to quickly construct the initial posture trajectory to provide initial values ​​for subsequent optimization iterations.

[0088] A trajectory target construction module constructs a trajectory optimization objective function including an angular velocity-related kinetic energy term and an attitude angle-related position potential energy term based on the attitude angle vector model;

[0089] To achieve precise control of the shield machine's posture during low-angle wall grinding, this paper builds upon the established posture angle vector model and further constructs a trajectory optimization objective function that incorporates the trade-off between kinetic energy and potential energy through a trajectory target construction module. This objective function guides the control system, and its structure determines the dynamic response of the controlled trajectory.

[0090] The pitch and yaw angles, as time functions, output by the attitude modeling module serve not only as state variables in the trajectory control model but also as the core computational objects in the objective function. The trajectory target construction module, based on the temporal evolution of attitude angles, defines kinetic and potential energy terms using angular velocity and angular deviation, respectively, thus forming an optimization target framework with a physical basis.

[0091] In this embodiment, the trajectory target construction module mainly includes three substructures: the kinetic energy term definition unit, the potential energy term definition unit, and the trajectory target assembly unit. These substructures work together to achieve the construction of a complete objective function.

[0092] In general, the change of shield attitude angle is accompanied by the generation of angular velocity, and the system needs to characterize the energy change brought about by angular velocity. The time derivative is processed to obtain the angular velocity vector , and construct the kinetic energy term in the following form:

[0093] ;

[0094] Where, Represents the attitude angular velocity vector; is the attitude inertia matrix; Indicates time attitude kinetic energy; is a constant coefficient; Represents the transposed form of the attitude angular velocity vector.

[0095] Specifically, to prevent the risk of sidewall contact caused by shield posture deviation, the present invention introduces a nonlinear potential energy term related to the posture angle into the objective function to simulate the "posture potential penalty" caused by the posture angle exceeding a critical range. This is accomplished by the potential energy term definition unit.

[0096] In some embodiments, the potential energy term can be expanded to include a weighted sum of multiple direction-sensitive vectors and multiple critical angles to enhance posture scene adaptability, as expressed as follows:

[0097] ;

[0098] Where, For the moment The energy of the “posture potential penalty term”; Indicates the number of sensitive directions; 、 Respectively Sensitive vectors, critical angles and penalty coefficients in each direction; is the two-dimensional attitude angle vector; For the The critical threshold of attitude in each direction; express The transpose of It represents the maximum value function, ensuring that the penalty term is generated only when the attitude angle exceeds the critical value, otherwise the term is zero. The trajectory target assembly unit is responsible for unifying the kinetic energy term and the potential energy term into a complete objective function. , which is expressed as:

[0099] ;

[0100] Where, represents the complete objective function; Indicates the upper limit of the control time domain; For the moment The energy of the “posture potential penalty term”; Indicates time The integral form ensures the global optimization of the objective function throughout the entire trajectory. The objective function structure supports the optimal trajectory through solving variational problems or pseudo-spectral discretization, and serves as the fundamental input for the subsequent trajectory control model construction.

[0101] To ensure structural continuity, in the subsequent trajectory constraint configuration module, and It will continue to participate in the constraint item encoding as a boundary and smoothness control variable, and together with the objective function of this module constitute the complete optimal control problem input.

[0102] Through the above structure, the present invention constructs a trajectory objective function with physical meaning, good mathematical form, differentiability and positivity based on the attitude angle-time function, and ensures its scalability and consistency with the constraint structure, meeting the practicality and accuracy of the dynamic control strategy in the shield attitude fine-tuning process.

[0103] A trajectory constraint configuration module, used to configure the boundary conditions of the trajectory optimization objective function and the constraint conditions of the second-order derivative of the attitude angle;

[0104] In order to ensure the accuracy and stability of the shield machine's attitude control during the advancement process, the present invention sets the boundary conditions of the trajectory optimization objective function and the constraints of the second-order derivative of the attitude angle in the trajectory constraint configuration module. This module is mainly responsible for ensuring that the generated trajectory meets the continuity, smoothness and boundary adaptability in practical applications. The design of the trajectory constraint configuration module is closely connected with the aforementioned attitude modeling module and trajectory target construction module to ensure that the optimization target solution process not only takes into account the objective function, but also integrates the actual requirements such as the starting and ending boundary conditions and the acceleration smoothness in the intermediate stage.

[0105] In this embodiment, the trajectory constraint configuration module includes two main functional units: a boundary constraint setting unit and a smoothness constraint setting unit. By properly configuring these constraints, excessive fluctuations in attitude angular velocity or discontinuous attitude angle changes can be effectively avoided during trajectory optimization, thereby improving the stability and accuracy of the shield machine's attitude control.

[0106] Generally speaking, in trajectory optimization problems, the setting of boundary conditions is very critical, which directly affects the initial and final values ​​of the optimization problem. In the implementation process of the present invention, the boundary constraint setting unit is used to configure the starting and ending boundary conditions of the trajectory. Specifically, these boundary conditions include the attitude angle and its rate of change at the starting time point and the ending time point. Through these constraints, it is ensured that the attitude angle of the shield machine is completely consistent with its expected value at the initial and terminal states of the trajectory. For the starting and ending attitude angle constraints, it can be expressed as:

[0107] ;

[0108] Where, and are the attitude angle vectors at the start and end of the trajectory respectively; and is the given desired attitude angle value. As an option, in addition to the boundary values ​​of the attitude angle, you can also set the boundary conditions of the angular velocity to ensure that the angular velocity of the trajectory at the start and end times is consistent with the given target angular velocity. These boundary conditions are expressed as:

[0109] ;

[0110] Where, and Respectively represent the angular velocity of the trajectory at the start and end time; and is the given desired angular velocity value.

[0111] Specifically, the smoothness constraint setting unit is mainly used to limit the acceleration of the trajectory over the entire time interval to avoid drastic acceleration changes during attitude changes, which helps prevent unstable motion of the shield machine during propulsion. To this end, in the present invention, the smoothness constraint is centered on the second-order derivative of the attitude angle and imposes an acceleration limit. This limit is achieved by controlling the integral upper limit of the acceleration, and the constraint satisfies the following integral relationship:

[0112] ;

[0113] Where, is the attitude angular acceleration; is the preset smoothness threshold; Indicates the upper limit of the control time domain; Represents the definite integral symbol.

[0114] In some embodiments, smoothness constraints are not limited to second-order derivatives but can be extended to higher-order derivatives to further optimize trajectory smoothness. For example, third-order derivatives can be considered to prevent drastic posture jumps. However, this embodiment primarily focuses on second-order derivatives to achieve better smoothing in practical applications.

[0115] All constraints generated by the boundary constraint setting unit and the smoothness constraint setting unit are ultimately encoded into a unified constraint structure for the trajectory control problem. The constraint encoding unit converts these constraints into a standard data format so that the subsequent trajectory control model can recognize and apply them.

[0116] A control trajectory generation module is used to establish a trajectory control model that describes the time evolution of the attitude angle according to the optimization objective function and its constraints, and obtain a discrete solution of the corresponding trajectory;

[0117] To achieve dynamic optimization of attitude control, this paper constructs an attitude angle vector model, designs an objective function, and configures constraints. Using a control trajectory generation module, this model describes the time evolution of the shield machine's attitude angles and obtains the corresponding discrete trajectory solution. This module, acting as a link between the objective function and constraints, directly influences the temporal distribution and accuracy of the final attitude trajectory and is the core decision-making and computational step in the attitude control closed-loop system.

[0118] The aforementioned trajectory target construction module provides an optimization objective function consisting of angular velocity kinetic energy and attitude angle potential energy. The trajectory constraint configuration module provides constraints such as boundary conditions and second-order derivative limits. Building on this foundation, the control trajectory generation module integrates these components into numerically solvable trajectory control equations and solves the optimal attitude trajectory using a time-domain discrete method.

[0119] In this embodiment, the control trajectory generation module includes a trajectory equation construction unit, a discrete solution unit, and a trajectory buffer unit.

[0120] In general, the trajectory equation construction unit first establishes a variational control model with attitude angle as the variable based on the principle of minimizing the objective function. This model uses time as the independent variable and attitude angle vector as the state function, and the objective is:

[0121] ;

[0122] Where, is the two-dimensional attitude angle vector; Represents the attitude angular velocity vector; is a symmetric positive definite attitude inertia matrix; It is the attitude potential energy function constructed based on the sensitive direction and critical angle; is a constant coefficient; Represents the definite integral symbol; Represents the transposed form of the attitude angular velocity vector; Represents the upper limit of the control time domain. Specifically, the potential energy function activates the nonlinear penalty term after the attitude angle exceeds the set threshold, which is expressed as:

[0123] ;

[0124] Where, It is the attitude potential energy function constructed based on the sensitive direction and critical angle; is a constant coefficient; is the two-dimensional attitude angle vector; is the attitude sensitive direction vector; is the critical angle threshold; is the penalty coefficient.

[0125] In one possible implementation, the trajectory equation construction unit performs first-order variation processing on the objective function based on the Lagrange principle, and then derives the Euler-Lagrange equation for the control trajectory. The control equation is a fourth-order differential equation of the following form:

[0126] ;

[0127] Where, is the contact potential energy function; and is the control coefficient; is a symmetric positive definite attitude inertia matrix; is the two-dimensional attitude angle vector; is the attitude angular acceleration; express Function attitude angle vector The gradient of the attitude angle; the fourth-order derivative, High-order smoothness control that represents the changing trend of attitude angle over time.

[0128] This construction transforms the original continuous-time trajectory minimization problem into a finite-dimensional numerical optimization problem with equality and inequality constraints. This problem consists of a cost function consisting of the minimized objective function terms and a constraint system consisting of bounds and acceleration limits output by the trajectory constraint configuration module. It exhibits clear solvability and convergence structure.

[0129] An instruction output module, used to convert the posture trajectory data generated by the trajectory control model into posture adjustment control instructions for the shield propulsion equipment;

[0130] To implement the optimal posture trajectory in actual shield machine propulsion, the present invention incorporates a command output module. This module accurately and efficiently converts the discrete posture trajectory data provided by the control trajectory generation module into control commands that can be directly recognized and executed by the shield control system. This module serves as the interface between trajectory planning and the shield machine. Its design must ensure that the data format, control parameters, and transmission protocol are highly compatible with the existing shield machine control architecture, while also meeting real-time and stability requirements.

[0131] The aforementioned control trajectory generation module has obtained a discrete trajectory solution based on the attitude angle optimization function and constraint structure solution. The output trajectory data set containing pitch angle, yaw angle and their derivative information is further processed in this module into the control variables required by each attitude control actuator in the shield propulsion system, such as propulsion cylinder displacement, pressure or voltage input.

[0132] In this embodiment, the instruction output module includes a posture mapping unit, a control format conversion unit, and a communication interface unit. The three units work together to ensure a complete closed-loop conversion of posture information from numerical solutions to physical instructions.

[0133] Typically, shield machine posture adjustment relies on the hydraulic propulsion system to actively adjust the posture vector of the shield's front shield or main body. To convert the posture angle trajectory into actual control variables, the posture mapping unit first performs a posture-to-actuation transformation based on the shield machine's propulsion cylinder layout and control model.

[0134] Specifically, in the two-dimensional attitude space, let the propulsion cylinder control quantity vector be , the following mapping relationship can be established:

[0135] ;

[0136] Where, is the two-dimensional attitude angle vector; To control the mapping matrix, the influence coefficient of the attitude angle on each cylinder control channel is defined; is the system bias, considering the initial offset of the device or mechanical zero point compensation.

[0137] In some embodiments, It can be obtained offline by calibrating the structure parameters of the shield and the arrangement scheme of the oil cylinder, or it can be adjusted in real time in actual working conditions combined with the linearized attitude response model.

[0138] As an option, to ensure that the instruction data matches the communication protocol of the shield control system, the control format conversion unit needs to further convert the above physical quantity mapping results into the corresponding control command format. Specifically, it includes voltage control format, displacement type control format or force control signal format.

[0139] For example, in the displacement control scenario, the output instruction format can be expressed as:

[0140] ;

[0141] In the formula, represents the target displacement instruction vector, with units of millimeters; is a proportional gain matrix, used to realize control sensitivity matching between different actuators; represents the thrust cylinder control quantity vector.

[0142] Specifically, the control format conversion unit can set the control logic of different actuator channels through the parameter table, including amplitude limiting protection, response delay compensation, unit conversion and other functions, thereby improving the execution safety and stability of the control instruction.

[0143] The communication interface unit is used to realize online publishing of instruction data, and uses standard industrial protocols for real-time communication with the shield master control system.

[0144] In one possible implementation, the communication interface is configured with a bidirectional channel, which not only transmits control instructions, but also receives current attitude feedback data of the shield, forming a closed-loop control loop. This feedback data will be used as the trigger basis for dynamic trajectory update in the real-time adjustment method.

[0145] In some implementation scenarios, the instruction output module also supports time synchronization and interpolation compensation functions of control instructions, which are used to generate high-frequency control signals through spline interpolation or piecewise linear interpolation when the trajectory time node and the sampling frequency of the control system are inconsistent, improving the continuity and stability of the control system response.

[0146] The shield small-angle wall grinding attitude dynamic control real-time adjustment method described below can be mutually referenced with the shield small-angle wall grinding attitude dynamic control model described above.

[0147] Please refer to the attached Figure 7 The application also provides a real-time adjustment method for dynamic control of a small-angle wall grinding posture of a shield machine, comprising the following steps:

[0148] S1. Based on the current posture angle information obtained during the propulsion process of the shield machine, a two-dimensional posture angle vector containing the pitch angle and the yaw angle is extracted, and compared with a set target posture angle vector to determine the initial state difference of posture adjustment;

[0149] S2. Based on the initial state difference, a trajectory optimization objective function containing an angular velocity related kinetic term and a posture angle related potential energy term is constructed as a function input for control trajectory derivation;

[0150] S3. On the basis of the constructed trajectory optimization objective function, combined with the set boundary conditions and acceleration smoothness constraints, a high-order differential control equation describing the evolution law of the posture trajectory is established;

[0151] S4. The high-order differential control equation is discretized in the time domain, and a numerical solver is called to obtain the corresponding discrete posture trajectory solution, and the trajectory solution is mapped and converted into a control instruction format recognizable by the shield propulsion system;

[0152] S5. The control instruction format is injected into the shield main control system according to the period, and the current posture angle information of the shield machine is synchronously collected, and the iteration process of steps S2 to S4 is retriggered according to the deviation between the latest feedback posture and the original target posture, so as to complete the dynamic update of the posture trajectory.

[0153] The method of the embodiment can be used to execute the control model embodiment described above, and has similar principles and technical effects, which will not be described here.

[0154] Although embodiments of the application have been shown and described, it is to be understood that the application is not limited to the details of the above-described embodiments, since the above-described embodiments can be modified in various ways, and substituted and changed in many ways without departing from the principles and spirit of the application, the scope of the application being defined by the appended claims and their equivalents.

Claims

1. The dynamic control model of shield small-angle wall grinding posture is characterized by: include: A posture modeling module is used to establish a two-dimensional posture angle vector model consisting of a pitch angle and a yaw angle based on the motion state of the shield machine in space, wherein the posture angle vector is a function of time; A trajectory target construction module constructs a trajectory optimization objective function including an angular velocity-related kinetic energy term and an attitude angle-related position potential energy term based on the attitude angle vector model; A trajectory constraint configuration module, used to configure the boundary conditions of the trajectory optimization objective function and the constraint conditions of the second-order derivative of the attitude angle; A control trajectory generation module is used to establish a trajectory control model that describes the time evolution of the attitude angle according to the optimization objective function and its constraints, and obtain a discrete solution of the corresponding trajectory; The instruction output module is used to convert the posture trajectory data generated by the trajectory control model into posture adjustment control instructions for the shield propulsion equipment.

2. The shield small-angle wall grinding posture dynamic control model according to claim 1 is characterized in that: The posture modeling module includes: The attitude angle analysis unit is used to collect the spatial attitude information of the shield machine in the construction coordinate system and convert the information into the representation of pitch angle and yaw angle; The attitude angle function generation unit is used to establish a continuous expression model of a two-dimensional attitude angle vector based on a time series.

3. The shield small-angle wall grinding posture dynamic control model according to claim 1 is characterized in that: The trajectory target construction module includes: The kinetic energy term definition unit is used to calculate the angular velocity based on the derivative of the two-dimensional attitude angle vector with respect to time, and is constructed in the form of; ； Where, Represents the attitude angular velocity vector; is the attitude inertia matrix; Indicates time attitude kinetic energy; is a constant coefficient; Represents the transposed form of the attitude angular velocity vector; A potential energy term definition unit is used to construct a potential energy function for reflecting the tendency of wall contact caused by the shield attitude angle exceeding a critical value, wherein the function is a nonlinear positive definite form with respect to the attitude angle; The trajectory target assembly unit is used to combine the kinetic energy term and the potential energy term into a trajectory optimization objective function for subsequent modules to call.

4. The shield small-angle wall grinding posture dynamic control model according to claim 3 is characterized in that: The potential energy term definition unit includes: An attitude sensitive direction setting unit is used to set a two-dimensional sensitive vector representing the main direction of shield attitude deviation; A critical angle threshold setting unit, used to configure a critical angle at which the attitude angle exceeds the wall contact limit; The potential energy function generating unit is used to generate a contact risk potential energy term, where the potential energy term is a nonlinear function of the attitude angle within the limit interval and depends on the difference deviation in a square form.

5. The shield small-angle wall grinding posture dynamic control model according to claim 1 is characterized in that: The trajectory constraint configuration module includes: Boundary constraint setting unit, used to set the starting and ending boundary values ​​of the attitude angle to ensure that the starting and ending points of the trajectory are consistent with the target attitude of the shield; The smoothness constraint setting unit is used to impose an acceleration intensity constraint on the attitude angle trajectory, and the constraint satisfies the following integral relationship: ； Where, is the attitude angular acceleration; is the preset smoothness threshold; Indicates the upper limit of the control time domain; Represents the definite integral symbol; The constraint encoding unit is used to convert the set boundary conditions and smoothness constraints into a unified constraint structure data format for the trajectory control model to call.

6. The shield small-angle wall grinding posture dynamic control model according to claim 5 is characterized in that: The constraint coding unit includes: Boundary value structure encapsulation unit, used to organize the boundary values ​​of the starting and ending attitude angles into a data structure with time tags; The acceleration limit encapsulation unit is used to uniformly encapsulate the integral upper limit value contained in the smoothness constraint and the corresponding acceleration variable identifier; The constraint set formatting unit is used to combine and standardize the formats of the above-mentioned multiple constraint structures according to a data format recognizable by the control trajectory generation module.

7. The shield small-angle wall grinding posture dynamic control model according to claim 1 is characterized in that: The control trajectory generation module includes: The trajectory equation construction unit is used to construct the trajectory control equation based on the trajectory optimization objective function and its constraints. The control equation is a fourth-order differential equation of the following form: ； Where, is the contact potential energy function; and is the control coefficient; is a symmetric positive definite attitude inertia matrix; is the two-dimensional attitude angle vector; is the attitude angular acceleration; express Function attitude angle vector The gradient of the attitude angle; the fourth-order derivative, High-order smoothness control that represents the attitude angle's temporal variation trend; A discrete solution unit, configured to perform pseudo-spectral discretization of the trajectory control equation in the time domain and solve the equation using a numerical optimization method to obtain an optimal posture trajectory; The trajectory cache unit is used to store the discrete results of the optimal trajectory and provide an interface for the instruction output module to read.

8. The shield small-angle wall grinding posture dynamic control model according to claim 7 is characterized in that: The discrete solution unit includes: A time node generation unit, a discrete time node set based on pseudo-spectral density distribution; The derivative matrix construction unit is used to generate a pseudo-spectral derivative matrix corresponding to each order of derivatives based on a set of time nodes.

9. The shield small-angle wall grinding posture dynamic control model according to claim 1 is characterized in that: The instruction output module includes: The posture mapping unit is used to map the target value of the optimal posture trajectory at each moment into the control value of the corresponding shield propulsion cylinder; A control format conversion unit, used to convert the attitude target value into the voltage, force control or displacement control instruction format required by the propulsion control system; The communication interface unit is used to periodically send the control instructions to the shield propulsion main control system through the industrial control protocol to achieve continuous execution.

10. A method for real-time adjustment of the dynamic control of a shield machine's small-angle wall grinding posture, according to the dynamic control model for a shield machine's small-angle wall grinding posture according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1. Based on the current attitude angle information obtained during the shield machine's advancement, extract the two-dimensional attitude angle vector including the pitch angle and the yaw angle, and compare it with the set target attitude angle vector to determine the initial state difference of the attitude adjustment; S2. Based on the initial state difference, construct a trajectory optimization objective function including an angular velocity-related kinetic energy term and an attitude angle-related potential energy term as a function input for control trajectory derivation; S3. Based on the constructed trajectory optimization objective function, combined with the set boundary conditions and acceleration smoothness constraints, a high-order differential control equation describing the attitude trajectory evolution law is established; S4. performing time-domain discretization processing on the high-order differential control equation, calling a numerical solver to obtain a corresponding discrete attitude trajectory solution, and simultaneously mapping the trajectory solution into a control instruction format recognizable by the shield propulsion system; S5. Inject the control instruction format into the shield main control system periodically, and synchronously collect the current attitude angle information of the shield machine. Re-trigger the iterative process of step S2 to step S4 based on the deviation between the latest feedback attitude and the original target attitude to complete the dynamic update of the attitude trajectory.

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