The path planning algorithm is important for the safety and stability of self-piloting. In this paper, target bidirectionalRRT*(TB-RRT*) path planning algorithm based on target gravity and improved metric function is proposed to address the problems of low search efficiency, high randomness, slow convergence, and unsmooth path of the rapidly-exploring random tree star (RRT*) algorithm. Firstly, the algorithm introduces the target gravity and dynamically adjusts the sampling step to improve the search efficiency of the algorithm and reduce the randomness of the search tree growth; through the bidirectional tree growth strategy, the convergence speed of the algorithm is improved. Secondly, the smoothness of the planned paths is improved by considering both Euclidean distance and pinch angle effects on path planning with an improved metric function. Finally, the smoothing path with optimal path cost is obtained by the path selection method. Simulation results show that the improved TB-RRT* algorithm reduces the path length by 12.8%, the running time by 56.9%, and the number of sampled nodes by 43.8%.
Actuator saturation has an important influence on the stability of the quadrotor UAV (Unmanned Aerial Vehicle) control system. The characteristic of the control structure of the quadrotor UAV is that the inner loop control commanddirectlyaffects the actuator. Aiming at the problem of actuator saturation of quadrotor UAV attitude control, an attitudecontroller based on Conditioned Super-Twisting Algorithm (CSTA) is designed. The two sign functions in CSTAarereplaced by the hyperbolic tangent function, and the input of the hyperbolic tangent function is adjusted byagainparameter, thereby suppressing the chattering of controller. The experimental results show that the designed controllercan track the attitude command better than PID when the actuator is saturated. Compared with the CSTAalgorithm, thedesigned controller output chattering is significantly reduced.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.