Improved Dynamic Window Approach for Unmanned Surface Vehicles’ Local Path Planning Considering the Impact of Environmental Factors

Abstract

The aim of local path planning for unmanned surface vehicles (USVs) is to avoid unknown dynamic or static obstacles. However, current relative studies have not fully considered the impact of ocean environmental factors which significantly increase the control difficulty and collision risk of USVs. Therefore, this work studies two ocean environmental factors, namely, wave and current, given that they both have a significant impact on USVs. Furthermore, we redesign a kinematic model of an USV and the evaluation function of a classical and practical local path planning method based on the dynamic window approach (DWA). As shown by the results of the simulations, the path length was impacted mainly by the intensity of the environmental load and slightly by the direction of the environmental load, but the navigation time was significantly influenced by both. Taking the situation in still water as a benchmark in terms of the intensity and direction of the environmental factors, the maximum change rates of the path length were 8.6% and 0.6%, respectively, but the maximum change rates of the navigating time were 17.9% and 25.6%, separately. In addition, the average calculation time of each cycle was only 0.0418 s, and the longest time did not exceed the simulation time corresponding to a single cycle of 0.1 s. This method has proven to be a good candidate for real-time local path planning of USVs since it systematically considers the impact of waves and currents on the navigation of USVs, and thus ensures that USVs can adjust to the planned path in time and avoid obstacles when navigating in the real ocean environment.

Route Planning Algorithms for Unmanned Surface Vehicles (USVs): A Comprehensive Analysis

“…This inclusion aids in the assessment of predicted trajectories. In [47], because previous research in this field had not completely taken into account the influence of oceanic environmental elements, which notably amplify the challenges to controlling USVs and the potential for collisions, this study therefore focused on investigating the effects of two specific oceanic environmental factors-waves and currents-recognizing their substantial impact on USVs. Moreover, they authors reconfigure a kinematic representation for a USV and revise the assessment criterion for a traditional and pragmatic local route planning technique grounded in the dynamic window approach (DWA).…”

Ship Path Tracking with Real Disturbance and Exponential Cost Function

“…The parameters corresponding to this expression are as follows: Using the wave load formula in [19], and using the current load formula [3] which is similar to the wind load formula in [14]. The wave load is represented by Equation ( 3), the current load is represented according to Equation ( 4), and the wind load is represented by Equation ( 5).…”

Path-Planning Strategy: Adaptive Ant Colony Optimization Combined with an Enhanced Dynamic Window Approach

“…In a dynamic obstacle environment, it can ensure that the robot reaches the target point smoothly and shortens the time spent on the entire process. Wang et al [17] have redesigned the kinematic model of the underwater vehicle and the evaluation function for local path planning based on DWA to ensure that the vehicle can adjust to the target point and avoid obstacles promptly during navigation. Jin et al [18] propose a fusion algorithm RACO in complex dynamic environments, improves ant colony optimization, and proposes a two-level safety distance determination rule to handle unknown obstacles.…”