The high traffic density of railway line causes ballasted track to be extremely busy, and thus it is particularly important to improve the efficiency during railway maintenance. The changing law of dynamic characteristics of ballast bed during operation for the dynamic track stabilizer is conducive to optimize simulation analysis of the vehicle‐track system, so as to provide an optimized choice of operating parameters for promoting the pertinence and efficiency of dynamic track stabilizer. This paper presents the acceleration response of vehicle‐track‐subgrade system during operation of a WD‐320 dynamic track stabilizer and proposes the range of effective operating parameters. Then, the influence of operating parameters on the dynamic characteristics of the ballast bed is discussed for searching the optimal operating parameters under the single factor influence. Finally, the change laws including the support stiffness, damping, lateral resistance, and subsidence for the ballast bed are studied, and a parameterized model for dynamic characteristics of the ballast bed which can optimize the selection for operating parameters is constructed, rendering an effective reference variable for improving the simulation accuracy of the vehicle‐track coupling system.

This study proposes an innovative indoor localization algorithm based on the base station identification and improved black kite algorithm–backpropagation (IBKA-BP) integration to address the problem of low positioning accuracy in agricultural robots operating in agricultural greenhouses and breeding farms, where the Global Navigation Satellite System is unreliable due to weak or absent signals. First, the density peaks clustering (DPC) algorithm is applied to select a subset of line-of-sight (LOS) base stations with higher positioning accuracy for backpropagation neural network modeling. Next, the collected received signal strength indication (RSSI) data are processed using Kalman filtering and Min-Max normalization, suppressing signal fluctuations and accelerating the gradient descent convergence of the distance measurement model. Finally, the improved black kite algorithm (IBKA) is enhanced with tent chaotic mapping, a lens imaging reverse learning strategy, and the golden sine strategy to optimize the weights and biases of the BP neural network, developing an RSSI-based ranging algorithm using the IBKA-BP neural network. The experimental results demonstrate that the proposed algorithm can achieve a mean error of 16.34 cm, a standard deviation of 16.32 cm, and a root mean square error of 22.87 cm, indicating its significant potential for precise indoor localization of agricultural robots.

This paper presents a novel scissoring composite actuator which can successfully degenerate longitudinal vibration into scissoring vibration at actuator tips for potential medical applications. The proposed actuator consists of back mass, multilayer piezoceramic stack, front mass with netted pre-stress structure and beam. The actuator is driven by only a small axially poled multilayer piezoceramic stack. Moreover, a special symmetrical grooved structure is designed at the beam end to convert longitudinal driving vibration into opposite bending vibrations at the beam tip, resulting in scissoring-type composite vibration. The converted scissoring vibration concentrates on the beam tip without any deflection along other parts, which is highly desirable for narrow-spaced medical operations. The proposed design principle is demonstrated by structural analysis and verified by different types of finite element modeling (FEM) simulations, including Eigen frequency analysis, harmonic analysis, and transient analysis. The results reveal the design effectiveness of the actuator’s structure on scissoring-type mode excitation. Finally, a prototype of the proposed piezoelectric actuator is fabricated and tested, rendering superior performance and highly reliable mode conversion. The proposed actuator exhibits potential for advanced medical applications.

To improve the performance of the ultrasonic device during the endovascular operation, a scissor‐type ultrasonic catheter device with compound vibration was developed. The heat generated by friction between the target and the device affects its coagulation mechanism while the actuator contacts the tissue. The scissor‐type ultrasonic catheter device proposed in this study is expected to improve heat generation performance because it has the action of rubbing the object when it is pushed by combined vibration. In addition, since it is constructed by simple notch processing, it can be miniaturized and can be expected to be introduced into catheters. However, the observation of ultrasonic vibration during frictional heating is difficult, which is an issue for device design. In this paper, a thermal‐structure coupling analysis was done using the finite element method to calculate the heat generation efficiency and evaluate its coagulation performance.