A comparison between the results obtained by the MsP method and the numerical integration method proves that the former is ideal and credible in most regions. The effects of the time-varying parameters and the nonlinear deenthing caused by the gear teeth clearance on the amplitude–frequency characteristics of TsSCS components are studied. This is a part of research on transmission gears' thermal deformation for application in warship power rear drive systems.

In order to improve the efficiency of identifying parameters using the maximum likelihood method and to avoid the sensitivity of initial values, a proposed method that combines the advance and retreat method with the micro-genetic algorithm allows the initial value, the iterative increment, and the search interval to be gradually changed, and the initial value to start from zero, which ensures a stable and fast convergence compared with other algorithms.

This study proposed and verified a new idea for the crushing system of a mobile pellet harvester. As the key components of the crushing mechanism, the theoretical design calculation was given, and Ansys software was used to verify the feasibility of the design, specifically by computing the strength and stiffness. Field tests were conducted, and the test results met the requirements. This design can promote the further development of a mobile pellet harvester.

An electrohydraulic servo four-legged heavy-duty (FLHD) robot has been designed and developed. An integration layout cylinder design scheme for a non-lightweight hydraulic servo four-legged robot with high loads and torque of the hip joint is proposed, and the mathematical element analysis model for a parallel-executed cylinder (PEC) system is derived. A design idea of a force–position hybrid control scheme is determined for the PEC.

A novel structure of controlled multi-flow channel magnetorheological fluid semi-active mount is proposed, including four controlled channels and one rate-dip flow channel. For the proposed structural model, magnetic circuit analysis, rate-dip flow channel optimization design, and magnetorheological fluid mount damping analysis are performed, by developing a mathematical model for the semi-active mount of controlled multi-channel magnetorheological fluid.

This paper presents a concurrent tolerance design methodology for predicting the tolerance. This method integrates the product design with manufacturing and inspection to realize the balance of design tolerance, process tolerance, and cost. The proposed method was finally tested on the gap design between the taillight and bodyside of an automobile. The result shows the proposed approach improves design efficiency, shortens the development cycle, and reduces development costs.

Springback is an inevitable problem in the local bending process of hull plates, which leads to low processing efficiency and affects the assembly accuracy. Therefore, the prediction of the springback effect, as a result of the local bending of hull plates, bears great significance. In total, four springback prediction models, based on genetic and back propagation neural network (GA-BPNN) algorithms and the improved particle swarm optimization (PSO)-BPNN algorithms, are established.

It is difficult to achieve high-precision control due to friction of nonlinearity by traditional linear control methodology for the classical drive feed system at low speed. Here, the double-drive differential feed system is proposed to reduce the influence of the nonlinear friction at the ball screw pair of a linear feed system operating at low speed.

With establishing the mathematical model of the height of additive remanufacturing repair (ARM-repair), the precise position with theoretical basis of the weld seam under different wire-feeding speeds is obtained. The cooling effect is analyzed by numerical analysis and verified by experiments. The study can provide scientific theoretical support for blade ARM-repair height and related cooling parameters and has positive significance for improving blade repair technology.

The paper studies the three-dimensional contact finite element model of a double helical gear-shaft-bearing system based on the load-bearing contact analysis of the tooth surface. The results show that the tooth surface bearing contact of the system has the phenomenon of partial load due to the supporting deformation, and the unmodified herringbone gear has obvious contact stress concentration, which can be effectively improved by gear tooth modification.

In this paper, a new parameter, the compliance ratio λ, which could reflect the sensitivity of the main form of the flexible hinge's output displacement, is proposed and discussed in detail. The optimization of the compliant actuator is carried out analyzing the compliance features of different types of flexible hinges. Finally, an actual precision linear position platform will be taken as an example, to prove the key performance of the compliant actuator is much better.

Few pieces of literature could be found on vibration investigations of the 3K planetary gear set, a basic planetary drive structure with a more compact structure and wider transmission ratio range than the 2K-H. In this paper, the features of casing vibration and output torsional vibration are analyzed by establishing a dynamics model of a 3K-II gearbox. The advantages and disadvantages of these two vibration signals as a basis for 3K planetary gear system fault diagnosis are also compared.

The approximate calculation of a Stockbridge type damper's natural frequencies and its sensitivity were studied. The low-order frequency is highly sensitive to the cable's length, moderately sensitive to the damper's mass, and slightly sensitive to the eccentric distance and the damper's gyration radius. The high-order frequency is highly sensitive to the cable's length and the damper's gyration radius, moderately sensitive to the damper's mass, and slightly sensitive to the eccentric distance.

This paper aims to investigate the problem of the complex structure optimization of a thin-film diffraction imaging system. A method based on the Kriging model and the improved particle swarm algorithm is proposed to optimize the structure of the thin-film diffraction imaging system. After optimization, the flexible vibration of the improved thin-film diffraction imaging system is effectively suppressed, and the stiffness and stability of the supporting structure are significantly improved.

The monk I-Hsing (621–727) was an outstanding astronomer and mathematician during the Tang Dynasty. He was the first person to use scientific methods to measure the length of the meridian. History records that the waterwheel drove his hydromechanical clock, and the time-reporting device could accurately tell the time. Therefore, his hydromechanical clock had a timing function and an escapement regulation device.

This paper proposes a global interpolation algorithm that uses the trajectory pattern method for synthesizing low-harmonic trajectories. The synthesized trajectories and axis kinematic profiles are all smooth and only contain the fundamental frequency and its first three harmonics, which could avoid excitation of the system modes of vibration and reduce demand on the actuator dynamic response, thereby allowing the system to operate at higher speed and precision.

The variable hyperbolic circular-arc-tooth-trace (VH-CATT) cylindrical gear is a new type of gear. In order to research the contact characteristics of the VH-CATT cylindrical gear, tooth surface mathematical models of this kind of gear pair are derived based on the forming principle of the rotating double-edged cutting method with great cutter head in this regard.

The problem of inverse folding, determining the distribution of creases according to the desired shape, requires luck and artist inspiration, and it is a very complicated process. Here, we try to solve an inverse folding problem about a folding toy and get some kirigami patterns. It opens up a new way to solve the problem and can also help students understand the theory of mechanisms and machines.

A universal test-machine-based mechanically driven friction device was designed and manufactured. Friction tests were conducted on a third-generation high-strength steel QP980 with flat and curved dies at different pulling speeds and clamping forces. The formula for calculating the friction coefficients between curved contact surfaces was derived.

This article contains new propositions for modelling piezoelectric stack models by using existing classical and non-classical methods with the aim of improving piezoelectric stack capabilities. Polynomial chain fractioning is used to obtain a mechanical model with a cascade structure. To verify model output frequencies and amplitudes, edge graphs and structural numbers are used. With the help of Kelvin–Voigt, Mason and Maxwell slip models, an electromechanical model solutions are proposed.

The new pneumatic–electric hybrid actuator with pneumatic and electric driving modes has the problem of speed fluctuation in the process of driving switching. This affects the stability in the positioning process. In order to solve this problem, the motion characteristics of piston rod in pneumatic locking are studied. A relay and run strategy is proposed to solve the problem of speed fluctuation.

Based on the freedom and constraint topology approach and atlas approach, a new method for the synthesis of a redundant actuated compliant parallel mechanism is proposed, the synthesis conditions are given, and the synthesis process is formulated. With this proposed method, two new translation redundant actuated compliant parallel mechanisms are synthesized, and some new mechanisms have been synthesized. The degree of freedom analysis verifies the correctness and effectiveness of the method.

This paper investigates planetary gear reducers with double satellite gears. These reducers are present in present-day industrial robots, electric vehicles, etc. The paper deals with the dynamic behavior of the reducer as a whole system. The acceleration, velocities, and movements are solved for all elements based on the defined dynamic model. For a dynamic model definition, we used Lagrangian equations of the second kind. The results can be used in design, investigation, etc.

Small motor stator winding at the same time is difficult to guarantee the uniform arrangement of enameled wire. This paper proposes a three-phase parallel equivalent multi-wire winding robot. The manipulator structure is designed, and the joint motion planning simulation is carried out to verify the feasibility of the multi-wire parallel winding hybrid robot. The research results of this paper provide a theoretical reference for multi-wire parallel winding equipment control.

To solve the kinematics mapping problem for the joint space and the drive space of a hyper-redundant manipulator based on flexible cable actuation, which is the key for hyper-redundant manipulators to move strictly according to trajectory planning and avoid obstacles, a decoupling method for kinematics analyses of the flexible cable actuation space and the joint rotation space was proposed.

The electrically driven Stewart platform (EDSP) is used widely. However, the passive rotation (PR) on driven branch chains can generate posture error on the end effector. Compensation control strategy is designed to avoid effects of PR on posture accuracy of the 6-DOF (degrees of freedom) EDSP based on calculation and analysis. The validity of analysis and the effectiveness of the compensation method used to improving posture accuracy are proven by simulation and experiments on a 6-DOF EDSP.

This paper presents the force analysis and optimization of four versions of self-adaptive robotic fingers based on the simplest closed-loop 1 degree-of-freedom mechanism possible, namely the four-bar linkage. Two of these versions include prismatic joints. It was concluded that simpler designs in adaptive fingers do not necessarily mean weaker performances since the results are at least comparable with other designs with more degrees of freedom.

This study is focused on analyzing signal changes according to internal flow and temperature change by generating micro-leakage, unlike previous studies that experimented with no flow inside a chamber. In addition, a new application method utilizing a phase shift by post-processing the ultrasonic reception signal was proposed. By using the ultrasonic sensor, a different method was proposed for the measurement of micro-leakage of gaseous fuel that relied on the existing pressure sensor.

In the early stage of the creative design of mechanisms, design work was accomplished mainly based on researchers' experience and inspiration, resulting in a low design efficiency. Moreover, the derived mechanism configurations were very limited. An effective mechanism design method is based on the atlas of topological structures of kinematic chains. Our research on the structural synthesis of kinematic chain inversions plays an important role in the improvement of mechanism design efficiency.

This paper designs a type of bionic-gibbon robot with three links and two grippers. We apply the sliding-mode control to the swing motion of the robot. The bionic-gibbon robot can complete continuous brachiation motion on the irregularly distributed bars. Besides, compared with the two-link structure, the three-link structure introduced in this paper improves the swing efficiency and increases the swing height of the robot.

The influence of wind load on the vibration of ultra-high-speed elevator can no longer be disregarded, and the maximum horizontal vibration acceleration of the guide rail is positively correlated with the height of the building. In addition, the vibration acceleration of the same height rail increases with the increase in wind pressure. This study provides important guidance for researchers studying the horizontal vibration response of ultra-high-speed elevators.

In order to solve the problem of the nonlinear frequency response of a planetary gear transmission system, based on the lumped parameter theory, a nonlinear frequency response model with a bending torsion coupling of a planetary gear system is established by comprehensively considering the backlash, support clearance, time-varying meshing stiffness, static transmission error, external periodic excitation and other factors.

In this paper, we use the folded section hypothesis to determinate the ratchet tooth root bending stress and provide a normal mathematical model to calculate it. This model has been proved by the finite element analysis method and the ratchet experiment. It is recommended that this model be used to predict the ratchet tooth root bending stress in the ratchet design process.

It is more efficient and safe to use a sub robot to replace the mother robot to perform space exploration tasks full of challenges. A novel three-rocker-arm six-wheeled robot with adaptive obstacle-crossing capability was designed to form a sub-parent exploration system with a large robot and to perform exploration tasks. A prototype of the robot is developed, and the experiment results show that the robot can maintain stability in rugged terrain and has excellent ability to cross obstacles.