Search

Skin, as the crucial component of aircraft, should be milled along the edges of the frame to ensure the mounting accuracy. Traditional skin milling uses visual measurement and offline planning to generate a machining path that corresponds to the overall shape of the frame edge. To enhance adaptability and processing efficiency, an online planning method is proposed. However, it imposes greater demands on the computational efficiency, accuracy, and stability of the algorithm. In this paper, a real-time path planning method based on frame feature extraction and chronological feature optimization is proposed for the milling of attached frame-skin. The method uses a line laser to scan the surface features of both skin and frame structures, facilitating real-time extraction of feature structures. Periodic calculations of position and posture are conducted based on the time series, and a non-fitting method is used to generate a smooth and high-precision machining trajectory. The efficacy in achieving real-time path planning for the milling module is verified by experiments on prototypes of aircraft skin. The algorithm exhibits a duration of less than 8 ms in a run cycle, while maintaining accuracy within ± 0.5 mm. • Propose a real-time extraction method of the position and posture characteristics of the attached frame and skin structure. • Propose a path planning method using chronological features to improve path point continuity and establish a processing path. • The algorithm achieved a path planning period of less than 8 ms and maintained tracking path accuracy within ±0.5 mm. [ABSTRACT FROM AUTHOR]

Autonomous Mobile Robots' performance relies on intelligent motion planning algorithms. In autonomous mobile robots, sampling-based path-planning algorithms are widely used. One of the efficient sampling-based path planning algorithms is the Rapidly Exploring Random Tree (RRT). However, the solution provided by RRT is suboptimal. An RRT extension known as RRT* is optimal, but it takes time to converge. To improve the RRT* slow convergence problem, a goal-oriented sampling-based RRT* algorithm known as GS-RRT* is proposed in this paper. The focus of the proposed research work is to reduce unwanted sample exploration and solve the slow convergence problem of RRT* by taking more samples in the vicinity of the goal region. The proposed research work is validated in three different environments with a map size of 384*384 and compared to the existing algorithms: RRT, Goal-directed RRT(G-RRT), RRT*, and Informed-RRT*. The proposed research work is compared with existing algorithms using four metrics: path length, time to find the solution, the number of nodes visited, and the convergence rate. The validation is done in the Gazebo Simulation and on a TurtleBot3 mobile robot using the Robotics Operating System (ROS). The numerical findings show that the proposed research work improves the convergence rate by an average of 33 % over RRT* and 27 % over Informed RRT*, and the node exploration is 26 % better than RRT* and 20 % better than Informed RRT*. [ABSTRACT FROM AUTHOR]

In Wireless Sensors Networks (WSNs), researcher's primary focus is on energy preservation and prolonging network lifetime. More energy resources are required in case of remote applications of WSNs, where during active network stage some of the nodes die early, that shortens the network lifetime and decreases the stability of the network. It is mainly caused due to the non-optimal Cluster Heads (CHs) selection based on the single criterion and uneven distribution of energy. We propose a new distributed clustering protocol for both homogeneous and heterogeneous environments, named Optimized path planning algorithm with energy efficiency and extending network lifetime in WSN (OPEN). In the proposed protocol, we use timer value concept for efficient CH selection based on multiple parameters, e.g., residual energy, the average distance from its neighbors, and node density. Simulation results prove that OPEN performs better than the existing schemes regarding the network lifetime, throughput, and stability. The results explicitly explain the cluster head selection of OPEN protocol and efficient solution of uneven energy distribution problem. [ABSTRACT FROM AUTHOR]