Engineering Commons^™

Multi-Uav Collaborative Trajectory Planning Algorithm For Urban Ultra-Low-Altitude Air Transportation Scenario, Jie Cheng, Yuan Zheng, Chenglong Li, Bo Jiang

Journal of System Simulation

Abstract: The rapid development of the drone industry has promoted the opening of low-altitude, forming a wave of ultra-low-altitude air transportation in cities sweeping over the world. However, the existing trajectory planning algorithms do not consider the division method and operating rules of the ultra-low-altitude airspace. They are not suitable for the collaborative trajectory planning of multiple UAVs in the urban ultra-low-altitude air transportation scenario, which may restrict the development of the ultra-low-altitude air transportation industry. This paper explores a multi-UAV collaborative trajectory planning method for urban ultra-low-altitude air transportation scenario based on the airspace flight altitude layer architecture. Specifically, …

Multi-Uav Trajectory Planning Based On Adaptive Segmented Potential Field Method, Guangjian Tian, Jiyang Dai, Jin Ying, Ning Wang

Journal of System Simulation

Abstract: To solve the problems that the traditional artificial potential field method is prone to fall into the local extreme value, target unreachability and excessive curvature of the planned trajectory curvature in the application of UAV trajectory planning, on the basis of the layered potential field method, a method of adding a second local attractive field at the target point and an attractive set composed of the target attractive field is proposed. This method overcomes the defects of unreachable targets and easy falling into local extremes. In addition, a piecewise function is introduced into the original layered potential field method, …

Task Allocation Method For Multi-Uav Cooperative Reconnaissance In Complex Environment, Fuzhen Zhang, Yaoqin Zhu

Journal of System Simulation

Abstract: The existing cooperative planning methods of multiple UAVs often carry out path planning and task allocation separatly, which causes the cooperative scheme not being the best in a complex environment. The cost matrix of multi-UAV cooperative reconnaissance on heterogeneous targets is established. Aiming at the various obstacle constraints and the characteristics of UAV motion and track in complex environment, an improved PSO-AFSA is used to solve the single UAV track planning model. Hungarian algorithm is used to complete the cooperative allocation of reconnaissance tasks of UAVs. The simulation results show that the algorithm can make the flying range of …

Planning And Analysis On Uav Trajectory Based On Pce Method, Sijie Zeng, Yan Liang, Xiaojun Duan

Journal of System Simulation

Abstract: Focusing on the uncertainty in the UAV trajectory planning, combined with the artificial potential energy method, a UAV trajectory planning method based on polynomial chaos expansion (PCE), which can also efficiently obtain the optimal parameters of the model based on artificial potential field method is proposed. The PCE proxy model is established, and the stochastic collocation method is used to quickly solve the problem, so as to avoid the insufficient computing resources. Through the Sobol sensitivity analysis, the calculation overhead of the uncertainty parameters in the trajectory planning model is reduced. Cases of UAV trajectory planning prove the effectiveness …

Kinematics Analysis And Simulation Of Automatically Tracking Dental Surgery Lamp, Zerui Jiang, Lijun Yang, Li Jun, Xiaolong Jiao, Zheng Hang

Journal of System Simulation

Abstract: In order to solve the problem that the oral surgical lamp cannot automatically adjust the irradiation posture of the surgical lamp according to the face direction and oral cavity position, a six-degree-of-freedom automatic tracking visual manipulator solution is proposed. Coordinate conversion is achieved through binocular vision to obtain three-dimensional information of oral cavity position and face normal vector. The geometric method is introduced into the kinematics calculation, and the closed solution of the inverse kinematics is obtained. The correctness is verified by the Maltab programming and the introduction of numerical values. Five-degree polynomial motion planning is performed …

Trajectory Planning Of 6-Dof Manipulator Based On Inverse Multi-Objective Optimization, Xianyin Duan, Can Zhang, Zerun Zhu, Zhaoyang Sun, Guozhang Jiang, Xiang Feng

Journal of System Simulation

Abstract: In order to optimize the machining quality and production efficiency of manipulator, an inverse multi-objective determination method based on the optimization of manipulator stiffness and global travel is proposed. Establishing the forward kinematics model of manipulator, the inverse kinematics is solved by using behaviour tree. The stiffness performance evaluation index and the mathematical model of total stroke of joint angle are constructed to carry out the inverse solution multi-objective optimization. The 7-5-7 order polynomial joint space interpolation algorithm is designed for the trajectory planning. Compared with the commonly used cubic polynomial programming method, the manipulator trajectory obtained by …

Design And Simulation On Autonomous Landing Of A Quad Tilt Rotor, Supu Xiu, Yuanqiao Wen, Changshi Xiao, Haiwen Yuan, Wenqiang Zhan

Journal of System Simulation

Abstract: Aiming at the under-actuation of general quadrotors, a novel quad tilt rotor model is proposed. The model decouples the y-direction translation and roll rotation of a quadrotor by the four servos used respectively for the tilting control of the four propellers to realized the tilt hover and tilt flight of the UAV, the UAV can keep a tilt attitude which increases the maneuverability and the precise pose position and attitude control of the tilt UAV and ensures a good performance on the trajectory tracking and landing. A 5-degree polynomial optimization is used in UAV trajectory planning for the strong …

Gait Planning And Control Of Quadruped Robot With High Payload, Hu Nan, Shaoyuan Li, Huang Dan, Gao Feng

Journal of System Simulation

Abstract: A position controller for a quadruped robot with high payload was proposed. The robot was developed by the lab, and the high payload capacity was realized by the specific design of its actuation system, integrating novel high precision actuators, and by its legs, composed by a new family of parallel mechanisms. The foot trajectory was scheduled based on the Bezier curve in order to improve the stability of quadruped robot. The performance and efficiency of the proposed methods were verified by simulation and experiments.

Simulation Analysis Of Virtual Platform Of Close-Coupling Multiple Robots Combined Lifting System, Su Cheng, Yanlin Wang, Jitao Liu, Zhigang Zhao

Journal of System Simulation

Abstract: A framework of virtual simulation platform of close-coupling multiple robots combined lifting system was constructed. The model of the multiple robots system was established based on UG. The mathematical model of the mobile robot and the static equilibrium equation of the operated object was established. A collaborative control simulation system was set up based on ADAMS and MATLAB closed loop. In close-coupling multiple robots combined lifting system, according to two different trajectory planning, calculating draw of the mathematical model and the co-simulation model output curves were compared and analyzed to verify the correctness of the mathematical model of the …

Modeling Method Based On Reachable Set For Safety Path In Autonomous Vehicle Obstacle Avoidance, Cao Kai, Xiaoxiao Huang, Yu Yun, Liu Chun

Journal of System Simulation

Abstract: In view of problem in all possible uncertain behavior of vehicle unable existed by the traditional path planning algorithm, a modeling method was proposed which deemed a moving vehicle as a hybrid system switching dynamically between continuous and discrete mode, modeled an optimal trajectory for vehicle obstacle avoidance by using a single security target location, and built a safe state reachable set based on the trajectory beam of multiple security target locations. On this basis, the condition of the inevitable collision of vehicle was analyzed, and the optimal control problem with loose constraints for the vehicle obstacle avoidance was …

Trajectory Planning Of Wheeled Mobile Robot Based On Model Predictive Control, You Bo, Mingrui Wang, Li Zhi, Ding Liang

Journal of System Simulation

Abstract: Aiming at the underactuation of the Wheeled Mobile Robot (WMR) and considering the various limitations and constraints during the actual operation, a trajectory planning method based on the Model Predictive Control (MPC) is proposed.This method can deal with the kinematics constraints, physical constraints and obstacle avoidance constraints unifiedly and effectively. It can generate the feasible trajectories that conform to the characteristics of the car body model and satisfy the various constraints. It fully guarantees the feasibility, safety and efficiency of the autonomous driving of wheeled mobile robots. The simulation results fully verify the effectiveness of the proposed method.

Ads-B In Based Conflict Prediction And Conflict-Free Trajectory Planning For Multi-Aircraft, Siyuan Zhang, Xianying Li, Xiaoyun Shen

Journal of System Simulation

Abstract: For free flight of future, it is necessary to continuously detect conflicts and plan safe flight paths. Through in-depth analysis of detection principle of TCAS, combined with the characteristics of ADS-B data, the target within the scope of ADS-B IN surveillance is classified and given a risk factor, and the TCAS function is implemented in the ADS-B IN simulation software. For complex conflict scenarios with multi-aircraft, by meshing the conflict region and discretizing the flight procedure, the genetic algorithm is then used to calculate the optimal conflict-free trajectory based on risk factors. Two common multi-aircraft conflict scenarios are …

A New Method On Trajectory Planning For Mobile Robots Using Bezier Curves, Sun Lei, Lishuang Zhang, Zhou Lu, Xuebo Zhang

Journal of System Simulation

Abstract: In view ofthe trajectory planning for the mobile robots, an efficient method based on Bezier curves is proposed, which produces better solution with shorter path and faster trajectory, compared with the existing methods. The problem of trajectory planning is divided into path planning and velocity planning. A Bezier curve is used to connect each two line-segments to obtain shorter paths. It is proved that the order of the used Bezier curves is at least five to ensure the curvature continuity of the whole path. Taking a differential-driven wheeled mobile as an example, to follow the planned path steadily and …

Intelligent And Secure Underwater Acoustic Communication Networks, Chaofeng Wang

Dissertations, Master's Theses and Master's Reports

Underwater acoustic (UWA) communication networks are promising techniques for medium- to long-range wireless information transfer in aquatic applications. The harsh and dynamic water environment poses grand challenges to the design of UWA networks. This dissertation leverages the advances in machine learning and signal processing to develop intelligent and secure UWA communication networks. Three research topics are studied: 1) reinforcement learning (RL)-based adaptive transmission in UWA channels; 2) reinforcement learning-based adaptive trajectory planning for autonomous underwater vehicles (AUVs) in under-ice environments; 3) signal alignment to secure underwater coordinated multipoint (CoMP) transmissions.

First, a RL-based algorithm is developed for adaptive transmission in …