Search

In solving the inverse kinematics of the redundant hydraulic manipulator of the demolition robot, there are problems of multiple solutions and the contradiction between the real-time and accuracy of the calculation. A series calculation strategy combining global mapping and local search was proposed. Firstly, the inverse kinematics solution was mapped from the global space to the local space of the working point by the global neural network model, and then the inverse solution results were obtained by the local search of the gravitational search algorithm. To avoid the GSA falling into the local minima and improve the search speed and accuracy, an improved gravitational particle adaptive step search strategy was proposed to balance the exploration and development stage of the population. The simulation and experimental results show that the global than local inverse solution algorithm can avoid the multi-solution problems and ensure the stability and accuracy of the solution on the basis of real-time inversion. [ABSTRACT FROM AUTHOR]

AbstractThe present study aims to investigate the dynamic performance of the disk hydraulic brake system in a mining belt conveyor. To achieve this, a simulation model of the hydraulic system for the belt conveyor is designed and constructed using AMESim. It is recognized that brake disk deformation can lead to brake shock, thus an ADAMS rigid-flexible coupling model for hydraulic disk brakes is established. Furthermore, the concept of rigid-flexible coupling mechanical systems is introduced into the hydraulic system to enable interaction between physical quantities. Use fuzzy logic rules to adjust parameters in Simulink, and in response to the suboptimal control of braking and acceleration, a compact non-model-based adaptive algorithm is incorporated into the conventional PID control algorithm. Employing mechanical modeling and multidisciplinary dynamic collaborative simulation technology, a simulation system integrating electromechanical and hydraulic aspects is developed for the disk hydraulic brake of belt conveyors. This system is employed to conduct simulation studies on the closed-loop control of braking disk speed and deceleration/acceleration for belt conveyors. The study findings reveal that the non-model-based adaptive PID control algorithm, in comparison to fuzzy PID, not only demonstrates quicker and more stable responses across various dynamic performance curves but also markedly reduces the axial oscillation amplitude of the braking disk under braking conditions. [ABSTRACT FROM AUTHOR]

AbstractThe brake disk and friction material parameters were taken as design variables, with the negative damping ratio of the unstable mode as the optimization target. The central composite design method was employed to obtain suitable data sample points. A neural network response surface model was constructed to predict the real part values of the unstable mode. Structural optimization design was then conducted using a screening method to derive optimized parameters for the brake disk structure and physical parameters such as density, elastic modulus, and Poisson’s ratio of the friction material. The optimized coefficient of the negative damping ratio of the brake system’s unstable mode was enhanced, thereby reducing the likelihood of brake squeal. Harmonic response analysis showed a significant optimization effect on the curve of brake disk amplitude fluctuations with frequency. These findings offer valuable insights for improving the stability of disk brake systems. [ABSTRACT FROM AUTHOR]