944 results about "Path tracking" patented technology

The present invention represents a procedure for compensating the heave movement of offshore cranes. The dynamic model of the compensation actuator (hydraulically operated winch) and the load hanging on a rope are derived. Based on this model, a path-tracking control unit is developed. To compensate the movement of the ship/watercraft caused by waves, the heave movement is defined as a time-varying disturbance and is analyzed with respect to uncoupling conditions. With a model expansion, these conditions are satisfied, and an inversion-based uncoupling control law is formulated. To stabilize the system, an observer is used for reconstructing the unknown state by means of a force measurement. Furthermore, the compensation efficiency can be improved by predicting the heave movement. There is proposed a prediction method in which no ship/watercraft models or properties are required. The simulation and measurement results validate the heave compensation method.

The invention relates to a system to provide local mobile geographic information service based on GPS and mobile terminal. The system comprises: a wireless communication network, a GPS position apparatus and mobile terminal, and an internet and path tracking server. The innovation of the invention is adding the following software functional modules in the mobile terminal: a wireless communication module, a GPS receiving module, an interface displaying module, an interest point inquiring module, a path planning module, a positioning module, a path tracking module, a GIS engine module, a database management module and a data layer made up of an interest point database, a geographic data file, a geographic data index file, a geographic data topological file and a initialization configuration file. The system achieves the advantages of simple, practical, smart in data layer design, convenient in inquiring, low in cost and easy to implement. For storing geographic space data and integrating many software functional modules in the mobile terminal, the system in the invention enable the user to enjoy localized real time geographic space position service conveniently at any moment with less dependence on the server.

The invention discloses a regional path tracking control method for an autonomous land vehicle. A problem that collision of a vehicle with a road boundary or surround obstacle occurs because shapes and sizes of the vehicle and the road are not considered by the existing tracking control method can be solved. The method comprises the following steps: establishing a two-dimensional road model; establishing a mathematical model associated with a vehicle path tracking problem; calculating a roadable region boundary line within a certain distance in front of the vehicle; establishing a vehicle system model; carrying out a design of a regional path tracking control model and selecting a controlled quantity being an optimum front wheel steering angle at current time; according to the optimum front wheel steering angle, controlling a steering execution mechanism to make motion to enable the controlled vehicle to be driven in a roadable region, provided by a vehicle sensing system, within a certain distance in front of the vehicle. When the two-dimensional road model is established, the shapes and sizes of the vehicle and roads are taken into consideration, thereby reducing the possibility of collision of the vechile with the road boundary and thus improving safety of the autonomous land vehicle.

A vehicle control system for causing a follower vehicle to follow a leader may have a tether system mounted to the follower vehicle. The tether system may include a tether having an end adopted to be attached to the leader, a length sensor, and an angle sensor. A path tracking system operatively associated with the tether system determines a path traveled by the leader. A path control system operatively associated with the path tracking system and the follower vehicle causes the follower vehicle to follow the path traveled by the leader. A spacing control system operatively associated with the path tracking system and the follower vehicle causes the follower vehicle to maintain a predetermined spacing between the follower vehicle and the leader.

The invention provides a model ship based autonomous navigation control simulation system and method of an under-actuated unmanned ship. The whole system is arranged on a model ship, and the model ship is arranged in a simulated navigation channel; the system comprises an environment sensing sub system, a path programming sub system and a motion control sub system; the environment sensing sub system collects the navigation state of the model ship and simulates environment factor information; according to the navigation state of the model ship and the simulated environment factor information, the path programming sub system carries out navigation programming to obtain the tracking route, the set speed and the set course; and the motion control system combines a course tracking model, a path tracking model, the route deviation, the course deviation and the speed deviation to calculate the rudder angle and propeller rotating speed instruction needed in next navigation of the model ship and control a steering engine and a propeller. According to the invention, simulation experiments are carried out on the model ship, an instance is provided for operation and control experiments of large ships, important guarantee is provided for safe navigation of large ships in inland rivers, and the system reduces the difficult and cost of experiments of the large ships.

The invention relates to an intelligent electric vehicle path tracking model prediction control method, belonging to the technical field of control. The aim of the invention is to adopt the intelligent electric vehicle path tracking model prediction control method, wherein the model prediction control method can take account of the safety constraints of a whole vehicle simultaneously and realizeseclectic optimization among vehicle path tracking performance, safety and whole vehicle performance effectively. The method gives thought to intelligent electric vehicle path tracking model building in limited conditions and yaw stabilization controller design based on model prediction control as well as the tracking performance of the vehicle, the safety of the vehicle, the whole vehicle performance, driving comfort and saving and control of energy in the process of carrying out control strategy deduction, and improves the dynamic performance of the whole vehicle. The method gives thought tothe tracking performance of the vehicle (path following and speed following), the safety of the vehicle (preventing slipping, locking, sideward inclining or drifting), the whole vehicle performance (accelerating and braking performance), driving comfort (the change of torque cannot be too great) and saving and control of energy (saving energy on the premise of meeting the performance). The dynamicperformance of the whole vehicle is improved.

The invention discloses an intelligent automobile path tracking hybrid control method, and belongs to the technical field of intelligent automobile lateral control. The intelligent automobile path tracking hybrid control method comprises the following steps that step 1, an automobile lateral control preview kinematics model at a low speed is established; step 2, an automobile lateral control dynamic model at a high speed is established; and step 3, a path tracking hybrid controller is designed, the path tracking hybrid controller comprises a lateral controller, a supervisor and a switching stability fuzzy controller, wherein the lateral controller is designed based on PID control and model predictive control, the supervisor determines a tracking mode based on longitudinal vehicle speed, and the switching stability fuzzy controller is designed based on a fuzzy control theory. The intelligent automobile path tracking hybrid control method effectively solves the problem of lateral controlperformance requirements under high-speed and low-speed working conditions of an intelligent automobile, and the easy realization, accuracy and stability of path tracking of the intelligent automobile are improved.

The invention provides a road surface crack detection method based on dynamic programming, comprising the following steps: 11, utilizing a crack with low fuzzy gradient and path tracking contrast ratio for effectively strengthening; 12, utilizing a dynamic programming method to effectively detect the crack with poor continuity; and 13, utilizing a support vector machine model to classify the extracted crack. The road surface crack detection method based on dynamic programming of the invention can effectively extract the crack with low contrast ratio and poor continuity.

The invention relates to an automatic parking method based on hierarchical planning. Sensing modules arranged around a vehicle obtain information about obstacles in an ambient environment; a parking space size and a parking space type as well as obstacle existence in the parking space are deduced; when the parking space size meets the need and no object exists in the parking space, initial planning based on numerical optimization is carried out; when the initial planning does not meet the parking need, A* search planning and secondary value optimization planning are carried out based on current vehicle pose and parking space information and environmental obstacle information; and after successful planning, a trajectory control point is sent to a vehicle-mounted controller and the vehicle-mounted controller controls a vehicle steering wheel, an accelerator pedal and a brake pedal, so that the vehicle is parked in the target parking space. In addition, the invention also relates to an auxiliary automatic parking system comprising a sensing module, an HMI display module, a path planning module, and a vehicle path tracking module. Compared with the prior art, the automatic parking method and the auxiliary system have advantages of strong environmental adaptability and accurate trajectory calculation.

The invention discloses an automatic navigation control method of an agricultural machine. The method comprises the following steps of 1, measuring motion state data of the agricultural machine at current time in real time by a GPS receiver; 2, performing comparison and analysis on motion state data and predefined path data according to a preview control method, thereby calculating transverse deviation and operation direction deviation; 3, performing fuzzification through a fuzzy control algorithm, then introducing a fuzzy amount into a fuzzy controller, thereby obtaining a front-wheel rotation angle; establishing geometric model through an improved pure tracking algorithm, thereby calculating the front-wheel rotation angle; combining the front-wheel rotation angles which are obtained through the two algorithms for obtaining a combined front-wheel rotation angle; and 4, controlling the agricultural machine in real time according to the combined front-wheel rotation angle, thereby realizing path tracking. According to the automatic navigation control method of an agricultural machine, two navigation methods are combined for realizing automatic control, thereby realizing high stability, high interference resistance and effective system robustness improvement. Through combining the two navigation methods, the advantages of the two navigation methods are combined so that the automatic navigation control method satisfies operation requirement in dry land and paddy field.

The invention relates to an unmanned vehicle path tracking control device and method based on multipoint tracking. The unmanned vehicle path tracking control device is composed of a GPS data acquisition module, a vehicle speed acquisition module, a data preprocessing module, a calculation module and a wire control execution system. The unmanned vehicle path tracking control method comprises the steps that a GPS position and attitude information of a vehicle are collected and acquired in real time, and GPS coordinates of points on a tracking track path are collected; the track information is preprocessed, and a tracking track is smoothed by Gaussian filtering; and a preview window, a preview interval and preview points of a tracking path reference point are determined, the heading angle deviation and the position deviation of the current vehicle coordinate point and the selected interference preview points are calculated, the front wheel rotation angle corresponding to each preview coordinate points is calculated according to the position deviation and the heading angle deviation, the front wheel rotation angle corresponding to each preview coordinate point is determined according to road condition information and vehicle condition information, and each front wheel rotation angle is added and output according to equal weight to achieve the purpose of path tracking.

The invention discloses a path tracking guiding control method of a dynamic positioning ship. The path tracking guiding control method of the dynamic positioning ship comprises the steps that (1) a geodetic coordinate system, a hull coordinate system and a mathematical model of the ship are built; (2) a guiding strategy is generated through by setting the geometrical position relation between a path generated by path points and the ship, and the expected heading of the ship at the current moment is calculated; (3) control moment needed by controlling the ship to achieve the expected heading is obtained through application of a control algorithm; (4) longitudinal thrust needed by controlling the ship to be at the expected movement speed is calculated. According to the path tracking guiding control method of the dynamic positioning ship, the expected heading, on a high-speed path tracking linear section, of the ship and the expected heading, on a high-speed path tracking turning section, of the ship are calculated according to track information and the relative position between the flight path and the ship, the movement speed of the ship is controlled through the longitudinal thrust, the calculation process is simple and easy to implement, and the path tracking guiding control method of the dynamic positioning ship is applicable to engineering application.

The invention provides a coordination control method for vehicle path tracking and stability. The method includes the following steps: step S1. performing vehicle modeling; step S2. performing estimation on a vehicle state and system interference based on Kalman filtering; and step S3. performing integrated control on the vehicle path tracking and stability. The method establishes a vehicle dynamics model and a path tracking model, and designs an estimation method of the vehicle state and steering system interference. An upper-layer controller is designed by using a sliding mode control method, which aims to ensure the stability of a vehicle itself while reducing course deviation and lateral deviation during a path tracking process. In a lower-layer controller, a method for optimal distribution of a wheel tire force is designed, and according to requirements of the upper-layer controller and combining yaw and roll stability conditions of the vehicle, directional control distribution ofthe wheel tire force is achieved. The coordination control method can ensure that a wheel independently drives the smart automobile to achieve a path tracking effect, and also ensures lateral and roll stability of the smart automobile itself.

The invention discloses an intelligent vehicle laser radar maneuvering multi-target tracking method based on an IMM-MHT algorithm, and the intelligent vehicle laser radar maneuvering multi-target tracking method belongs to the technical field of intelligent vehicles. The intelligent vehicle laser radar maneuvering multi-target tracking method is implemented by generating a tracking gate firstly, receiving a measurement value and performing detection and identification on the measurement value, making a joint hypothesis of a flight path and measurement, simplifying and managing the hypothesis, performing detection and identification on the flight path, and finally filtering and predicting the flight path. The intelligent vehicle laser radar maneuvering multi-target tracking method comprises the steps of: step (1), forming a flight path tracking gate; step (2), receiving a t-moment measurement value and identifying the t-moment measurement value by adopting an image processing method; step (3), generating an association hypothesis of measurement and a flight path in the tracking gate; step (4), managing the hypothesis; step (5), calculating information such as speed and angular speed of the flight path, and identifying the flight path; step (6), and filtering and predicting the flight path by adopting an interactive multi-model algorithm. Through integrating the interactive multi-model algorithm and a multi-hypothesis tracking algorithm, the intelligent vehicle laser radar maneuvering multi-target tracking method can better deal with the intelligent vehicle maneuvering multi-target tracking problem in a complex environment.

The invention provides an autonomous driving path tracking control method of a crawler-type mobile robot. With the autonomous driving path tracking control method of the crawler-type mobile robot adopted, the accuracy and reliability of the path tracking of the mobile robot can be improved. The method comprises the following steps that: the current pose information, mass center speed information and driving wheel rotating speed information of the crawler-type mobile robot are acquired; the pose information of the crawler-type mobile robot in a prediction time domain is determined according to the obtained information through the kinematics and dynamics models of the crawler-type mobile robot, and the determined pose information is compared with expected path information, so that pose deviation in the prediction time domain can be obtained; with minimizing the sum of predicted pose deviation, predicted control quantity increment and predicted course angular velocity change in a path tracking process adopted as an objective, the optimization function of nonlinear model prediction control can be determined; the optimization function is minimized through constraint conditions, so that an optimal control sequence can be obtained; and therefore, the crawler-type mobile robot tracks an expected path according to the output pose information of the optimal control sequence so as to autonomously travel.

The invention is applicable to the technical field of pilotless driving and provides a path tracking method for a pilotless automobile. According to the method, the pilotless automobile is subjected to differential positioning by virtue of a high-precision satellite. The path tracking method comprises a straight path tracking method or a turning path tracking method. The straight path tracking method comprises the step of driving based on a distance deviation between a current position of the pilotless automobile and an expected straight path and a deviation between a course angle and an expected course angle of the pilotless automobile. The turning path tracking method comprises the step of carrying out turning driving based on a deviation distance from a current position of the pilotless automobile to a turning point and a deviation between a driving direction and a turning direction of the pilotless automobile. The path tracking method provided by the embodiment of the invention has the beneficial effects that a principle and a calculation process are simple, the calculated amount is small, and the method is easily realized in an embedded system; and besides, the combination of the high-precision satellite and a path tracking algorithm is realized in the embedded system, so that the path tracking accuracy is increased.

The invention provides a high-accuracy nonlinear path tracking control method for an under-actuated marine vehicle. According to the method, the change rate of the sideslip angle of the vehicle is regarded as an uncertain item, the parameter uncertainty in a dynamic model, unmodeled dynamics and external environmental disturbances are regarded as lumped uncertainty, and an observer is adopted to conduct real-time observation on kinematic uncertainty and dynamic uncertainty; a traditional aspect-angle guiding method is adopted to calculate an expected aspect angle; a nonlinear path tracking controller based on the observer is designed, and the kinematic and dynamic uncertainty are compensated; a tracking differentiator is adopted to simplify the controller to make the controller more suitable for engineering application. According to the method, the influences of the parameter uncertainty in the dynamic model, the unmodeled dynamics and the external environmental disturbances on path tracking are eliminated, and the accurate tracking control over an expected path of the vehicle is achieved.