Fuzzy Based Adaptive Dimension Parking Algorithm Including Obstacle Avoidance for Autonomous Vehicle Parking

Autonomous vehicle parking and obstacle avoidance navigation have drawn increased attention in recent times for autonomous vehicle-related solutions. Existing autonomous vehicle parking algorithms generally fail to mimic the human-like tendency to adapt naturally, and most of these designs are practically fixed. They do not preserve adaptive nature with machine dynamics, especially vehicles related. In this paper, a novel fuzzy-based adaptive dimension parking algorithm (FADPA) is proposed that integrates obstacle avoidance capabilities to a standalone parking controller that is made adaptive to vehicle dimensions in order to provide human-like intelligence for parking problems. This algorithm adopts fuzzy membership thresholds with respect to vehicle dimensions to enhance the vehicle's path during parking with taking care of obstacles. It is generalized for all segments of cars, and different simulation results are presented to show the effectiveness of the proposed algorithm.

Dynamic characteristics for coal shearer cutting unit gearbox housing

Long wall mining is most widely used in coal mining of China, and coal shearer is the most important machine due to its direct role in cutting coal. Nevertheless, coal mining enterprises are suffering from faults of coal shearer, especially cutting unit gearbox housing (CUGH). Published dynamic studies on CUGH have not considered the excitation caused by gear meshing and complete machine vibration. Due to the apparent lack of experimental validation of these published papers, the dynamic response of CUGH is not convincing. In this study, dynamic behavior of CUGH is investigated both theoretically and experimentally for finding out failure mechanism and improving reliability. Complete machine vibration and gear meshing vibration are two excitation sources for CUGH, and vibration is transferred via articulated holes and bearing holes. Hence, complete machine dynamics model is established for obtaining force on articulated holes. Dynamics model of gear transmission system is established for obtaining force on bearing holes. Stochastic cutting forces model is established as external load of complete machine dynamics model. Dynamics response is calculated by finite element model established by ANSYS. A measurement system to capture three-dimensional vibratory motions under realistic working conditions of coal mines is implemented by National Energy Mining Equipment Laboratory of China. Direct comparisons between predicted and measured results are presented to demonstrate the accuracy of the proposed model in predicting three-dimensional vibrations of CUGH. Maximum deformation and stress positions of CUGH are determined, and the excitation sources are investigated.