173 results about "Optimal trajectory" patented technology

Various types and levels of operator assistance are performed within a unified, configurable framework. A model of the device with a model of the environment and the current state of the device and the environment are used to iteratively generate a sequence of optimal device control inputs that, when applied to a model of the device, generate an optimal device trajectory through a constraint-bounded corridor or region within the state space. This optimal trajectory and the sequence of device control inputs that generates it is used to generate a threat assessment metric. An appropriate type and level of operator assistance is generated based on this threat assessment. Operator assistance modes include warnings, decision support, operator feedback, vehicle stability control, and autonomous or semi-autonomous hazard avoidance. The responses generated by each assistance mode are mutually consistent because they are generated using the same optimal trajectory.

The invention discloses a dynamic automatic drive lane-changing trajectory planning method based on real-time environment information. A rollover limitation trajectory vertical coordinate, an optimal trajectory and a collision avoidance trajectory terminus security area are calculated; the relation between the rollover limitation trajectory vertical coordinate and the security area is compared, the positional relation between the optimal trajectory vertical coordinate and the security area is further compared, and then lane-changing decision-making is conducted. According to the dynamic automatic drive lane-changing trajectory planning method based on the real-time environment information, and a polynomial trajectory equation which dose not depend on time is adopted to represent a lane-changing trajectory curve, so that the problem that hypotheses of a speed and an accelerated speed are too strong is avoided; furthermore, collision avoidance algorithm and rollover prevention algorithm which are based on reaction time are introduced to guarantee security of lane-changing; then the optimal trajectory in a safe trajectory cluster is determined through real-time speed adjusting; and finally, an optimal lane-changing trajectory of real-time dynamic state is output through a trajectory generation module to guide an autonomous vehicle to complete a lane-changing behavior, and therefore a set of complete dynamic autonomous vehicle lane-changing trajectory planning module is built.

The present invention provides computer implemented methodology that permits the safe landing and recovery of rotorcraft following engine failure. With this invention successful autorotations may be performed from well within the unsafe operating area of the height-velocity profile of a helicopter by employing the fast and robust real-time trajectory optimization algorithm that commands control motion through an intuitive pilot display, or directly in the case of autonomous rotorcraft. The algorithm generates optimal trajectories and control commands via the direct-collocation optimization method, solved using a nonlinear programming problem solver. The control inputs computed are collective pitch and aircraft pitch, which are easily tracked and manipulated by the pilot or converted to control actuator commands for automated operation during autorotation in the case of an autonomous rotorcraft. The formulation of the optimal control problem has been carefully tailored so the solutions resemble those of an expert pilot, accounting for the performance limitations of the rotorcraft and safety concerns.

The invention relates to a genetic-algorithm-based trajectory planning optimization method for a mobile mechanical arm. According to the technical scheme, the method comprises the following steps of first establishing a forward kinematic model and an inverse kinematic model of a multi-degree-of-freedom mobile mechanical arm; then fitting a joint trajectory by adopting a composite curve of a quartic polynomial mathematical model and a quintic polynomial mathematical model, and calculating solutions of the corresponding mathematical models according to a linear constraint equation; next selecting a trajectory optimization target according to the principles of shortest motion time, minimum spatial motion distance and less than or equal to maximum set joint torque of the mobile mechanical arm; and finally globally optimizing the optimization target by utilizing a genetic algorithm to obtain an optimal trajectory curve of an end actuator of the mechanical arm. According to the method, the trajectory planning efficiency and the tracking accuracy of the mechanical arm are improved, and the problems of real-time trajectory planning of the mobile mechanical arm and trajectory planning optimization and control of the mechanical arm in an uncertain environment are also solved; and the trajectory planning optimization method for the mobile mechanical arm is effective.

The present invention provides an intersection condition-orientated unmanned vehicle trajectory planning method based on the Bezier curve and the VFH algorithm. The method includes the following steps that: 1) the starting point pose P0 (x0,y0,theta0) and destination point pose P3 (x3,y3,theta3) of current trajectory planning are acquired; 2) a trajectory cluster A1 from the starting point pose P0 (x0,y0,theta0) to the destination point pose P3 (x3,y3,theta3) is generated through adopting a three-order Bezier curve model; 3) the trajectory cluster A1 is screened according to a maximum curvature constraint, so that a trajectory cluster A2 is obtained, collision detection is performed on A2, so that a collision-free trajectory cluster A3 is obtained; 4) if A3 is not empty, an optimal trajectory is selected from A3 according to a trajectory smoothest principle and is outputted to a control layer, and the method is terminated, otherwise, the method shifts to step 5; 5) a movement region in the original VFH algorithm is improved, so that a fan-shaped movement region is built; 6) obstacle information is utilized to establish a grid map; 7) the fan-shaped movement region is divided into a plurality of fan-shaped regions, and whether an obstacle exists is judged; 8) the Bezier curve is used in combination, and optimal trajectory points are selected; and 9) with a discrete point set generated in the step 8 adopted as control points, a B-spline curve is generated, and the B-spline curve is adopted as the final trajectory of an unmanned vehicle.

The invention discloses a real-time trajectory planning method for an autonomous vehicle. The real-time trajectory planning method comprises the steps of: S1, acquiring relevant information of the autonomous vehicle in real time; S2, generating a reference trajectory, a feasible trajectory cluster determined by means of the reference trajectory and a speed corresponding to each feasible trajectoryin the feasible trajectory cluster based on the relevant information of the autonomous vehicle; S3, calculating an action of each feasible trajectory according to the feasible trajectories and the corresponding speeds thereof by utilizing a target optimization function taking safety and efficiency as targets, and selecting the feasible trajectory with the least action as the expected optimal trajectory, and carrying out optimization to obtain an expected optimal velocity corresponding to the expected optimal trajectory, wherein the target optimization function is obtained according to the principle of least action and an equivalent force method. The real-time trajectory planning method can enable the autonomous vehicle to imitate driving features of a driver in an unknown environmental condition, and can plan a trajectory that best meets the driver's driving expectation by taking the safety and efficiency as the driving targets according to the surrounding vehicles and environmental information in real time.

A method and apparatus for LCL resonant converter control utilizing Asymmetric Voltage Cancellation is described. The methods to determine the optimal trajectory of the control variables are discussed. Practical implementations of sensing load parameters are included. Simple PI, PID and fuzzy logic controllers are included with AVC for achieving good transient response characteristics with output current regulation.

The invention belongs to the technical field of a path planning for unmanned vehicles, and especially relates to a dynamic trajectory planning method for an unmanned vehicle based on local optimum. The method is characterized by, according to different positions and corresponding different operating conditions of obstacle vehicles on the road, selecting an optimal reference trajectory and carryingout dynamic trajectory planning; analyzing unmanned vehicle lane change intention generation and lane change executable conditions, and according to the prediction of the position and speed of surrounding obstacle vehicles, carrying out fitting to obtain a locally optimal lane change trajectory at the initial moment when obstacle avoidance lane change is decided, and serving the optimal trajectory as a local reference trajectory; and generating a trajectory cluster that can be driven by the unmanned vehicles and combining designed velocity distance and cost functions with a loss function, andselecting an optimal trajectory from the trajectory cluster through nonlinear model predictive control. The method can realize obstacle avoidance, lane change and overtaking in various complex conditions, and also takes into account the comfort of passengers in the unmanned vehicles and road driving efficiency and the like.

A feedback control system for steering a tool along a well-plan. Optimum steering instructions may be generated by a recursive optimization of multiple objectives. These objectives can include accuracy and quality. The quality objective can include the objective of drilling a smooth borehole by minimizing strain energy and torsion. The accuracy objective can include the objective of minimizing the deviation of the borehole trajectory during the real-time drilling process from a predefined well-plan. The trajectory control problem, therefore, can be a multi-objective problem where, in some embodiments, the weightings of the individual objectives can be adjusted along the process.

An target vertical trajectory for a flight plan is produced using aircraft performance characteristics taking into account only the altitude constraints, but ignoring any speed and time constraints. The target vertical trajectory is evaluated for violations of altitude, speed, and time constraints and on the basis of other criteria. An alternative vertical trajectory is generated by randomly changing parts of the target vertical trajectory, and this alternative is likewise evaluated. If the child vertical trajectory has a more robust evaluation, it becomes to new target vertical trajectory; otherwise the previous target vertical trajectory remains in place. The alternative vertical trajectory generation process is performed repeatedly and over time the target vertical trajectory evolves toward an optimum trajectory solution.

Pulse width modulation is provided for controlling a resonant power converter, particularly for dimming of light emitting diode arrays without loss of efficiency. Dynamic oscillation due to the beginning of a pulse width modulated pulse burst is limited by shortening of the first and/or last pulse of a pulse bust such that the first pulse of a subsequent pulse burst close to or to connect with a full load steady-state voltage/current trajectory of the power converter. Pulse shortening made be made substantially exact to virtually eliminate dynamic oscillation but substantial reduction in dynamic oscillation is provided if inexact or even performed randomly.

The invention relates to a model-constraint-based mechanical arm energy optimal trajectory planning control method and device. The model-constraint-based mechanical arm energy optimal trajectory planning control method comprises the steps that initial conditions are set and mechanical arm joint angle position description with respect to time is calculated and obtained through a cubic spline interpolation algorithm; on base of the mechanical arm joint angle position description and in combination with a dynamics model, a continuous function of moment with respect to time is obtained; a nonlinear constrained planning model taking mechanical arm movement energy consumption as the optimizing target is established, and in combination with the mechanical arm joint angle position description, thecontinuous function of the moment with respect to time and friction force energy consumption, energy consumption of a target function is solved; and on base of the nonlinear constrained planning model taking mechanical arm movement energy consumption as the optimizing target, the minimum value of energy optimal trajectory planning is iteratively solved adopting a sequential quadratic planning algorithm, and a mechanical arm optimal trajectory is obtained. Compared with the prior art, the model-constraint-based mechanical arm energy optimal trajectory planning control method and device do notneed a large number of complex calculation and have good real-time performance, and energy consumption is least.

The present video tracking technique outputs a Maximum A Posterior (MAP) solution for a target object based on two object templates obtained from a start and an end keyframe of a whole state sequence. The technique first minimizes the whole state space of the sequence by generating a sparse set of local two-dimensional modes in each frame of the sequence. The two-dimensional modes are converted into three-dimensional points within a three-dimensional volume. The three-dimensional points are clustered using a spectral clustering technique where each cluster corresponds to a possible trajectory segment of the target object. If there is occlusion in the sequence, occlusion segments are generated so that an optimal trajectory of the target object can be obtained.

The invention provides an unmanned surface ship optimal trajectory tracking control method based on a reinforced learning method. The unmanned surface ship optimal trajectory tracking control method based on the reinforced learning method comprises the following steps: S1, establishing an unmanned surface ship system mathematical model and a desired trajectory system mathematical model without considering a disturbance condition; S2, establishing a dead zone mathematical model, so as to obtain an unmanned surface ship system mathematical model introducing the dead zone; and further obtaining an tracking error system; S3, establishing an identifier system; and S4, evaluating whether the control strategy meets the requirements or not through an optimal cost function; if the control strategymeets the requirements, outputting the control strategy to the unmanned surface ship system as an optimal control strategy; and if the control strategy does not meet the requirements, evaluating whether the regenerated control strategy meets the requirements or not through the optimal cost function, and repeating the above process until the optimal control strategy is obtained and output to the unmanned surface ship system. The invention solves the technical problem that the unmanned ship optimal control method in the prior art does not consider the dead zone or completely unknown system dynamics, and the accuracy and robustness of the control system are reduced.

The invention belongs to the technical field of vehicle obstacle avoidance control methods, and discloses a vehicle obstacle avoidance trajectory planning and tracking control method. The vehicle obstacle avoidance trajectory planning and tracking control method comprises the steps of: decomposing an obstacle avoidance process into trajectory planning based on optimization and trajectory trackingcontrol based on model predictive control, establishing a trajectory optimization problem aiming at time optimum and comprising a plurality of constraints based on a three-section sinusoidal curve oflateral acceleration, and acquiring the optimal trajectory of obstacle avoidance through optimization solution; and establishing a two-degree-of-freedom vehicle control model, taking path tracking performance and the optimal steering angle as cost functions, and designing the optimal trajectory tracking controller based on a model predictive control idea, so as to achieve effective obstacle avoidance.

A system and method of generating optimised aircraft flight trajectories on Flight Management Systems with limited computational power that takes into account developing operational conditions, air traffic constraints and aircraft performance in a timely manner on the flight management system that can allow tactical flight plan changes to be incorporated without unduly introducing operational or financial penalties to the operator. An example method involves parameterisation of optimal trajectories as functions of operational parameters thereby allowing computational systems to use such computed functions in the air to determine the optimal trajectory or flight profile required for the specific operating conditions quickly and accurately.

The invention provides an autonomous vertical parking method based on a high-precision map. The method comprises the steps that a vehicle acquires parking space information based on the high-precisionmap and environmental information of a parking lot and road edge road measurement sensors, position attributes of the vehicle to be parked and positional relationship attributes of the vehicle in a global coordinate system are determined, switching points are determined accordingly, the switching points are fitted through an arc or spline curve, a cost function is constructed under the conditionthat the requirements for vertical parking path constraints and the minimum parking space constraint are met, and a trajectory with the smallest cost function is selected as the final optimal trajectory. By means of the method, the smoothness of vehicle movement control can be ensured, shaking of a steering wheel of the vehicle in the parking process is eliminated, and safe parking is achieved.

The present invention provides an explicit guidance law for a rocket with a terminal speed, a trajectory inclination angle and overload constraint. The explicit guidance law for a rocket is formed by integration of an optimal trajectory-shaping guidance law and a terminal speed control scheme. The optimal trajectory-shaping guidance law can control an aircraft to hit a target from a predetermined direction, the terminal speed control scheme controls the transverse maneuverable accelerated speed of the aircraft bending so as to control the prolonging of flight distance to regulate the size of the terminal speed, and the size of the transverse maneuverable accelerated speed is determined through an iteration correction algorithm. The analysis guidance law can satisfy the terminal trajectory inclination angle and the terminal speed constraint, and allow an aircraft to approach to the maneuverable accelerated speed of the target to gradually decrease to 0; further, the present invention provides a method for determination of coefficients of guidance law for a rocket, namely the coefficients of guidance law for a rocket are determined through proper selection of features of a linear approximation system; and moreover, a coefficient stability domain of the guidance law for the rocket is obtained so as to strictly prove that only if the coefficients of guidance law for a rocket are in the stability domain the guiding system is stable and the aircraft hits a target at a small angle of attack.

The invention discloses a trajectory optimization method of a midcourse guidance with constraints. The trajectory optimization method is used for reducing a shift velocity of a terminal guidance in anintercepting missile. The method comprises the following steps: establishing a kinematic equation of a whole trajectory in a longitudinal plane of the intercepting missile including a trajectory constraint and a terminal constraint, and constructing an intercepting missile trajectory optimization model according to an optimal trajectory of midcourse guidance with constraints set by the method; and optimizing a solution of the trajectory by adopting an hp self-adaptive pseudo-spectral method. According to the method, the shift velocity of the terminal guidance in the intercepting missile can be reduced, a good flight regime of the terminal guidance can be provided and an intercepting precision is improved. And the method is a promising trajectory manner.

Embodiments disclosed pertain to systems, methods and apparatus for the initialization of Computer Vision (CV) applications on user devices (UDs) comprising a camera and a display. In some embodiments, an optimal camera trajectory for initialization of a Computer Vision (CV) application may be determined based on an initial camera pose and an estimated pivot distance. For example, the initial camera pose may be estimated based on a first image captured by the camera. Further, the display may be updated in real-time with an indication of a desired movement direction for the camera. In some embodiments, the indication of desired movement direction may be based, in part, on a current camera pose and the optimal trajectory, wherein the current camera pose may be estimated based on a current image captured by the camera.

The invention provides a global time optimal trajectory programming method of industrial robot dynamic speed regulation. The global time optimal trajectory programming method comprises the steps thattrajectory points which may overrun are detected in advance by a searching mechanism based on iterative backwards of a fixed searching range, the trajectory points are divided into three classes according to the overrun conditions, corresponding algorithms are provided by a nonlinear problem segmentation linear idea, and particularly when a joint deceleration overruns, pushback and nudge of the trajectory points and a peak cut algorithm are combined to perform speed regulation. Algorithm dynamic speed regulation enables the overrunning trajectory points to meet constraint requirements, starting points of the searching range are continually issued to perform, and synchronous operation of searching detection, dynamic speed regulation and trajectory execution is ensured. By performing smoothing and limiting regulation on the velocity of movement and acceleration of a robot cartesian space and joint space synchronously, an original trajectory is guaranteed to move at a reasonable speed andin a constraint condition range; and time optimal of dynamic speed regulation is realized, smooth and efficient motion of the robot in a whole space is ensured, and the precision and operating efficiency of the robot are improved.

The present invention relates to a minimum base disturbance trajectory planning method for a space robot, in particular to a minimum base disturbance trajectory planning method for a space robot based on an improved chaotic particle swarm algorithm, which belongs to the field of aerospace technology; the steps included in the present invention To: (1) establish the kinematic equation of the 6-DOF space robot; (2) parameterize the joints with the 7th-order sine polynomial function; (3) establish the equation of the fitness function, including the constraints of the position of the base Disturbance, attitude disturbance, joint velocity and angular velocity constraints; (3) In order not to fall into local optimum and quickly find the optimal solution, the chaotic particle swarm optimization algorithm is improved; (4) The improved chaotic particle swarm optimization algorithm is used to solve the unknown Parameters, the optimal trajectory of the space robot can be obtained in the case of the minimum disturbance of the base posture. The invention focuses on solving the problem of trajectory planning for a 6-degree-of-freedom free-floating space robot, and uses the improved chaotic particle swarm algorithm to find out the optimal trajectory of the space robot when the disturbance of the base seat posture is minimal, and the effect is good.

The invention relates to a trajectory optimization method for a spraying robot based on reinforcement learning. The trajectory optimization method determines the optimal spraying trajectory through image acquisition, image processing, graphic three-dimensional reconstruction, graphic discretization, initial point selection and optimal trajectory strategy selection, wherein the image processing includes camera calibration, image correction and stereo matching. The advantages of the invention lie in that the trajectory optimization method for the spraying robot based on reinforcement learning can plan a feasible path according to different states in different environments, is short in decision-making time and high in success rate and can meet the real-time requirements of online planning, thereby overcoming the shortcomings of poor real-time performance and great calculation amount of the traditional manipulator path planning method.