35results about How to "Avoid the impact of control accuracy" patented technology

The invention relates to a steering-law singularity avoiding aircraft attitude control system, comprising an attitude task managing unit, an attitude controller, an attitude measuring unit, a gyro group steering-law unit, a frame angle position measuring unit, a control moment gyro group and an aircraft. The gyro group steering-law unit calculates the frame angle rate of the control moment gyro group by cooperating control moment gyro angle momentum table, zero motion algorithm and pseudoinverse steering-law algorithm, and adopts the angle rate value as the set signal of the control moment gyro group to improve the control precision of the aircraft attitude. The steering-law singularity avoiding aircraft attitude control system introduces the steering-law design method that chooses frame angle rate and the initial value of frame angle position based on look-up table, realizes accurate moment output of the control moment gyro group, avoids the singularity problem produced in the process of calculating frame angle rate of the control moment gyro group by the pseudoinverse steering-law algorithm as well as avoids the deadlock problem caused by the control moment gyro steering law when adopting zero motion algorithm and robust pseudoinverse steering-law iterative computations.

The invention provides a neural network adaptive control method applied to a servo system in order to improve the control accuracy of the servo system, which realizes nonlinear compensation and interference suppression of the servo system and improves the tracking accuracy and the robustness of the servo system. In addition, a speed closed loop is not needed, so the entire system can be quite conveniently designed, is easy to implement in engineering and reduces the cost.

The invention provides a direct-set torque and rotational inertia simulating system and a control method thereof. The control method comprises providing the driving torque of the measurement input shaft of a torque sensor and collecting driving torque signals, computing the target torque of a load motor through a bench controller according to set load torque and set rotational inertia and the driving torque signals, sending load motor target torque instructions to a motor direct torque controller, and receiving the load motor target torque instructions and controlling the load motor to output corresponding torque through the motor direct torque controller. According to direct-set torque and rotational inertia simulating system and the control method thereof, by taking the torque as the controlled target, influence of acceleration computing errors on control precision can be avoided; adjusting control parameters according to different bench controllers can be omitted, and usage simplicity and dynamic responsiveness can be obtained; redundancy monitoring for the operation status of the bench controller can be achieved, so that the reliability of a bench can be enhanced.

The invention provides a neural network self-adaptive control method applied to a servo system, aiming to improve the control accuracy of the servo system. The neural network self-adaptive control method realizes nonlinear compensation and interference suppression to the servo system and improves the tracking accuracy of the servo system. The servo system mainly comprises a reference model, a self-adaptive controller and a neural network controller. In addition, based on a speed ring accurate reference model, a position ring controller is very simple in design so that the whole system is rather convenient in design, thereby being easy to carry out in engineering.

The invention discloses a neural network and active disturbance rejection composite control method for a three-axis tripod head servo motor. The method is characterized by comprising following steps of (1) establishing a three-axis tripod head internal frame servo system dynamical equation with a Stribeck friction model, (2) designing an active disturbance rejection controller for the dynamical equation established in step (1), and (3) designing an RBF neural network, combining the RBF neural network with the active disturbance rejection controller to form an RBF neural network active disturbance rejection supervisory controller. According to the method, better response speed and control accuracy can be achieved in a nonlinear system, the stability and robustness of a control system can beensured, the introduction of neural network can improve the adaptive ability of the system, and the method can adapt to a larger range of a controlled object under the condition of satisfying controlperformance requirements.

The invention discloses a self-adaptive robust control method for compensating a dead zone inversion error based on a neural network and belongs to the field of electromechanical servo control. The invention is based on an adaptive robust control method, for the problem of dead zone nonlinearity widely existing in a motor servo system, a smooth and continuous mathematical model is used to provideapproximate inverse transformation of a dead zone required for feedback linearization, a single-hidden-layer neural network capable of performing online learning is designed to compensate an inversionerror from approximate inversion, in addition, a parameter adaptive law for processing parameter uncertainty is derived, a nonlinear robust feedback term is designed to suppress the influence of imperfect modeling, a compensation error or other interferences, the Lyapunov theorem is used for proving the stability of a proposed control algorithm, and a wide comparison simulation result shows thata proposed adaptive robust controller for compensating the dead zone inversion error based on the neural network has better control performance.

The invention discloses an ARC control method based on the expected track and interference compensation of a motor servo system and belongs to the field of electromechanical servo control. According to the ARC control method, an expected track-based regression device is adopted to design an adaptive law according to the uncertainty of system parameters, so that the influence of measurement noiseson parameter estimation can be effectively reduced; according to a designed interference observer, the state information of acceleration does not need to be known, and only one adjustable parameter isprovided, and therefore, hardware cost and calculation burden are effectively reduced, and the application of the method to engineering is facilitated; a self-adaptive robust algorithm is adopted, therefore, the influence of non-linear characteristics on the control precision of the servo system is effectively eliminated; and the high-precision control performance of the provided control scheme is verified through theoretical verification and simulation analysis, and the global asymptotic stability of the system is ensured.

The invention relates to an anti-interference method for sampling of an aircraft electric braking system. Because of an infinite dv/dt value, interference of a measured signal mainly happens at the edges of PWM waves, it no measure is taken, an interference point is very likely to be acquired, and error braking is caused. According to the method, an AD sampling point is placed in the position away from the PWM edges as much as possible, when the PWM duty ratio is smaller than 50 percent, the AD sampling period is located in the middle of a high level of the PWM waves, and as is shown in the second graph, when the PWM duty ratio is larger than 50 percent, the AD sampling period is located in the middle of a low level of the PWM waves.

The invention discloses an automatic driving control method in a complex environment. The automatic driving control method comprises the following steps: 1, collecting data of a target vehicle; 2, separating characteristic data, and positioning the position of a target vehicle and the driving environment of the target vehicle; 3, obtaining the distance between the target vehicle and the lane marker line through calculation, wherein the difference value between the distance and the expected distance is calculated, judgment is conducted according to the difference value, if it is judged that following is kept, the step 6 is executed, and if not, the step 4 is executed; 4, judging whether the target driving environment meets a lane changing condition or not, if yes, executing lane changing, and if not, judging that following is kept, and executing the step 6; 5, enabling the target vehicle to change lanes, and executing the step 6 after lane changing is completed; and 6, regulating and controlling the driving track of the target vehicle according to a car-following keeping method. According to the invention, lane changing control of the target vehicle is ensured to reach enough precision, and reasonable and controllable construction and maintenance cost is ensured.

The invention discloses a finite time control method for a vehicle-mounted photoelectric tracking platform based on a disturbance observer. According to the method, a disturbance observer and a finitetime controller are organically combined, complement each other and are used for controlling a photoelectric tracking platform. On the basis of a mathematical model of the photoelectric tracking platform, the disturbance observer is designed to observe disturbance borne by the photoelectric tracking platform, and the disturbance is used as a feed-forward quantity for compensation. Then, a given signal is compared with an actual signal to obtain a first-order error model containing an equivalent disturbance term, and a feedback control rate is designed by using a finite time control method onthe basis of the first-order error model. Through mathematical analysis, the relationship between the boundary of the steady-state error of a closed-loop system and the parameters of the controller under the condition of equivalent interference is given. The composite control method enables the photoelectric tracking platform to have better anti-disturbance performance and more excellent convergence performance.

The invention discloses a self-adaptive robust control method based on double-electric-cylinder synchronous motion error modeling, which belongs to the field of electromechanical servo control. The self-adaptive robust control method establishes a double-cylinder servo system model based on synchronous motion errors according to the characteristics of a double-electric-cylinder synchronous position servo system; aiming at the problem that parameter uncertainty and uncertainty of all models except the parameter uncertainty exist in an electromechanical servo system at the same time, parameter self-adaption and robust control are used for dealing with the uncertainty of the two systems respectively, and the problem of uncertain nonlinearity in a double-electric-cylinder synchronous servo system can be effectively solved; and a designed self-adaptive robust controller based on double-electric-cylinder synchronous motion error modeling is a synchronous control strategy based on a cross coupling method, has a good robustness effect on non-structural uncertainty such as coupling interference possibly generated in the synchronous movement process of double electric cylinders, and can ensure that position output can track an expected position instruction precisely.

The invention discloses a control valve for a hydraulic well mouth safety valve control system. The control valve comprises a valve body, a valve port formed in the center of the valve body, a valve plug positioned in the valve port, a front valve cover connected to one end of the valve body, and a rear valve cover connected to the other end of the valve body; an inner cavity hydraulic cylinder and a spring hole communicated with the inner cavity hydraulic cylinder are sequentially arranged in the valve body at one end connected to the rear valve cover; a piston connected with one end of the valve plug is matched in the inner cavity hydraulic cylinder, and separates the cavity hydraulic cylinder into a left part and a right part; a compression spring is matched in the spring hole, and is sleeved on the upper part of the valve plug; an oil inlet C is formed in the center of the front valve cover; an oil outlet B is formed on the side face of the valve body close to the front valve cover; the oil inlet C and the oil outlet B are communicated with the valve port; the center of the rear valve cover is provided with an inner hole partially communicated with the left part of the inner cavity hydraulic cylinder; a manual well opening screw is connected in the inner hole; and the side face of the rear valve cover is provided with a liquid communicating port A communicated with the left part of the inner cavity hydraulic cylinder. The control valve can be manually controlled when the control system fails.

The invention provides a self-adaptive path tracking method based on a distributed driving electric vehicle. The self-adaptive path tracking method comprises the following steps: establishing a vehicle dynamics model and converting the vehicle dynamics model into a state-space equation; according to the vehicle dynamical model, establishing a vehicle vertex dynamical model in combination with the variation range of the tire cornering stiffness; calculating a parameter estimation adaptive rate of the vehicle vertex dynamical model, and estimating an adaptive coefficient according to a real-time system state of the vehicle; establishing a vehicle state prediction model according to an adaptive coefficient estimation result, and predicting the future state and system output of the vehicle; and establishing and solving a path tracking optimization objective function and a lateral speed constraint objective function, and obtaining a first group of results of an optimal control sequence as a front wheel turning angle and four wheel driving/braking torque input of the vehicle at the next moment. The technical problems that when vehicle autonomous path tracking is used, perturbation of tire cornering rigidity can reduce the control precision of a controller, and robustness of vehicle path tracking control is reduced can be solved.

The invention relates to an endoscope body and a digestive endoscope robot, in particular to an endoscope body and a digestive endoscope robot. The objective of the invention is to solve the problem that the examination or treatment quality is affected because a doctor is prone to fatigue when standing and holding an endoscope for a long time. An endoscope handle (23) is installed in a driving mechanism shell (21), and a driving mechanism (22) is installed in the driving mechanism shell (21) and located at the lower end of the endoscope handle (23). The driving mechanism (22) comprises a first driving unit and a second driving unit, the first driving unit and the second driving unit are arranged in an up-down double-layer mode, and the first driving unit and the second driving unit directly drive one steel wire in the endoscope handle (23) through gear pairs respectively and drive the corresponding steel wire to be shrunk and released so as to achieve control over the bending angle of the tail end of the endoscope handle (23). The digestive endoscope robot comprises the endoscope body. The digestive endoscope robot is used in the operation process of the human digestive system.

The invention discloses a control method of an anti-interference electric six-degree-of-freedom parallel mechanism. The method comprises the steps: firstly, aiming at the characteristics of nonlinearity, strong coupling and the like of the electric six-degree-of-freedom parallel mechanism, establishing a mathematical model of the mechanism, and designing a cascade control model based on a linear actuator hinge space and a motion platform attitude space, wherein control based on the hinge space is taken as an inner ring, control based on the motion platform attitude space is taken as an outer ring, and the inner ring and the outer ring adopt PID controllers. Aiming at the characteristics that the load torque of a single linear actuator of the six-degree-of-freedom parallel mechanism is changed in real time and the control precision is influenced, the angular acceleration information of the actuator is acquired by adopting a state observer, and an anti-interference compensation controller is designed on the basis, so that the influence of disturbance on the control precision is eliminated; and finally, a Ziller-Nichols PID parameter setting method is applied to obtain an optimal PIDcontrol parameter. The control effect of the method on the electric six-degree-of-freedom parallel mechanism is superior to the control effect of a traditional PID method based on the hinge space.