Aiming at the problems of traditional Rapidly Exploring Random Tree (RRT) algorithm in route planning, such as slow speed, poor route quality and low flightability, a route planning algorithm based on integrated improvement of RRT was proposed. Firstly, in the selection of nodes to be expanded, the minimum sum of the distance between nodes and the target and the random sampling point is taken as the selection basis instead of the original method of determining nodes only according to random sampling points, so as to increase the probability of nodes near the target in the random tree being selected as nodes to be expanded. Secondly, in the process of node expansion, the reachable region of the next waypoint was determined according to the UAV dynamic constraints, and then multiple alternative nodes were randomly generated in this region. Then the route cost function is designed and the comprehensive generation value of the route formed by the alternative nodes is taken as the judgment criterion for node addition. Finally, B-spline curve smoothing is carried out to further improve the route quality. The simulation results show that the improved algorithm has obvious advantages in improving the planning speed and air route quality, and the obtained air route satisfies the UAV dynamic constraints and has high flightability.
Infrared images have shortcomings of background noise, few details, and fuzzy edges. Therefore, noise suppression and detail enhancement play crucial roles in the infrared image technology field. To effectively enhance details and eliminate noises, an infrared image processing algorithm based on multiscale feature prior is proposed. First, the maximum a posterior model estimating optimal free-noise results is constructed and discussed. Second, based on the extended 16 high-order differential operators and multiscale features, we propose a structure feature prior that is immune to noises and depicts infrared image features more precisely. Third, with the noise-suppressed image, the final image is enhanced by the improved multiscale unsharp mask algorithm, which enhances details and edges adaptively. Finally, testing infrared images in different signal-to-noise ratio scenes, the effectiveness and robustness of the proposed approach is analyzed. Compared with other well-established methods, the proposed method shows the evident performance in terms of noise suppression and edge enhancement.
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.