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Internal gearing power honing (IGPH) is a one-of-a-kind gear finishing process which is widely used in automobile gearbox systems, high-speed rail gears, etc. Current IGPH technology can cause an uneven quality of gears in mass production because of the invariable IGPH process parameters, so this paper presents a new method to ensure the stable cutting speed between the honing wheel and workpiece gear through a series of theoretical and experimental research studies.

This paper presents a novel united propulsive mechanism inspired by the frog’s hindlimb. This hybrid mechanism is composed of a planar six-bar linkage, which is designed using homotopy continuation and a spatial four-bar mechanism. The two sub-chains connected on the foot form a closed loop, which decreases the degrees of freedom (DoF) of the foot to 2. The preliminary simulations validate the amphibious function of the designed mechanism.

Industrial robots are required to perform a given task repetitively with high tracking precision. Iterative learning control (ILC) calculates the tracking error of each iteration and corrects the output control signals in accordance with a predefined learning operator. This research considers the changes of the dynamics characteristics when the robot has different types of payload. It provides an approach for adaptation of the ILC to the specific payload to achieve faster convergence.

Due to the defects of the internal structure and energy supply carrier, conventional deep sea unoccupied marine equipment cannot meet the requirements of low power consumption. The energy efficiency characteristics of floating bodies with different shapes were simulated, and the amplitude response operator (RAO), radiation damping, added mass and Froude–Krylov force of floating bodies with different shapes were compared.

Transrectal prostate brachytherapy (BT) can effectively treat prostate cancer. During the operation, doctors need to hold the ultrasound probe for repeated adjustments, which makes it difficult to ensure the efficiency, accuracy, and safety of the operation. We designed an 11 DOF (degrees of freedom) active and passive transrectal BT robot based on the analysis of the transrectal prostate BT process.

We present a novel exoskeleton based on deformable pneumatic actuators, known as McKibben muscles or artificial muscles. The aim of this system is to support a worker during overhead tasks, in which they need to lift the arms and hold that position for a long time. Simulations have been performed, starting from a mathematical model of the exoskeleton and of the artificial muscle. A first architecture of the complete device is also presented.

Similarity recognition of kinematic chains (KCs) is an important part of the mechanism innovation design, which can avoid isomorphism in the synthesis process and reduce the generation of redundant design schemes. In this paper, the new concepts of a loop tree (LT) and a loop tree matrix (LTM) have been proposed, which improve the efficiency of similarity recognition.

We introduce different test scenarios and set-ups for a force control assessment. The force control of Universal Robots (UR10e) and FerRobotics (ACF-K 109/04) are evaluated. A force/torque sensor, mounted below a work piece, measures the applied force by the UR or by the ACF. Results for both UR and ACF force control are presented for varying desired contact velocities and forces. These results show the advantage of the ACF-K 109/04 over the UR10e force control for highly dynamic scenarios.

To obtain all mechanical schemes, scholars in this field have proposed an innovative design method using kinematic chain configuration synthesis. However, the existing innovative design method easily produces redundant design schemes. We analyze the similar component discrimination method for mechanisms from the perspective of graph theory and apply it to the specialization of topological graphs to solve the problem of redundant design schemes.

We propose a novel mechanism synthesis approach for a 1-degree-of-freedom (DOF) rehabilitation robot, based on chord angle descriptor (CAD) and error tolerance expansion, to generate a pool of mechanism solutions from which mathematically and practically optimal solutions can be selected. A design example of a 1-DOF rehabilitation robot for upper-limb training is provided to demonstrate the efficacy of our novel approach.

We show how the operational modal analysis of a nonuniform wind turbine tower can be performed and used to acquire effective and reliable test results and dynamic behavior. Results show that a tailor-made genetic algorithm (using auto-MAC as the fitness function) is a practical approach to finding the optimal position of the sensors to obtain the best results for objective modes. We also accessed the updated finite element model with less than 1 % error compared to the frequencies from the test.

The article presents an approach to constructing the stability boundary in the parameter space of a nonlinear model of a wheeled vehicle – a bifurcation set, which extends the well-known concept of the critical speed of rectilinear motion to the case of circular modes. The approaches considered in the work are important for understanding the regularities of the change in the stability properties of the movement of wheeled transport systems.

A novel parallel leaf-spring carrying mechanism was designed and studied for high-precision fast wafer positioning and transfer in lithography. Displacement was used to calculate the equilibrium attitude, and the laser triangulation coordinate method was used for attitude measurement. The effectiveness of the attitude model was shown by numerical analysis and experimental verification. The methods can be used as a reference for the analysis and design of a complex parallel compliant mechanism.

We propose a kind of permanent magnet linear motor (PMLM) with inequality constraints to transform the constraint tracking control method based on the equality constraint and U–K inequality status transformation. This method solves the problem of the control system of equality constraints and inequality constraints without the need for the localization of a nonlinear system, proving that the method has certain advantages and can be extended to the safety constraint control of other products.

During manufacturing, machine failure can lead to fatal damage to both people and the environment, and non-destructive stress measurement is necessary to provide safety maintenance. This paper focuses on the feasibility and capability of deep learning algorithms in stress prediction using Barkhausen noise signals. Our findings pave the way for the implementation of auto-detection devices for metal materials in on-site manufacturing processes.

Many linkage mechanisms can be broken into components consisting of planar two-revolute (2R) and three-revolute (3R) serial chains, such as the five-, six-, and eight-bar mechanisms. In this study, a new method for the dimensional synthesis of the planar 3R serial chain for motion generation based on CGA is presented. The proposed method provides a new meaning for the motion synthesis of planar serial chains and can be applied to many other types of planar mechanisms.

Power line inspection not only wastes human and material resources, but also has a high-risk factor for manual inspection of power lines. Therefore, based on previous researchers, we designed a novel power line inspection robot. We also investigate walking stability of the robot on the line when encountering working conditions with crossing wind, since the power line is about 50–60 m from the ground and the inspection robots are greatly affected by wind.

A multi-degree-of-freedom dynamic vibration absorber (MDOF DVA) to suppress the vibration of the car body of high-speed trains is proposed. The MDOF DVA is installed under the car body, the main vibration frequency in each DOF of which is designed as a dynamic vibration absorber for lateral motion, bouncing, rolling, pitching, and yawing of the car body. The design principle of multi-DOF dynamic vibration absorption is analyzed by combining the design method of single DVA and genetic algorithm.

A positioning system for ultra-wideband (UWB) electric micro-tillers suitable for complex greenhouse environments was designed as the basis for realising unmanned micro-tillers to address the problem of frequent safety accidents of existing micro-tillers. The positioning system of the greenhouse electric micro-tiller designed in this paper demonstrates a stable performance and positioning accuracy to meet the needs of greenhouse rotary tillage operations.

In order to realize the overturning torque balance and active control of flow distribution of an axial piston pump, a new swashplate rotary valve distribution double-row axial piston pump was proposed. Its flow pulsation characteristics were studied, and a better number of plungers and flow distribution control schemes were optimized. The research can provide theoretical guidance for the flow control of double-row axial piston pumps with valve distribution.

The main purpose of this study was to establish a design process for the 2F1R thee-wheel tilting mechanism and to reduce the turning radius to fulfill steering geometry in order to reduce the steering torque for a better handling feel. The results were compared with road tests of real vehicles to verify the model.

Energy management strategies (EMSs) play an important role in hybrid electric vehicles. In this review, EMSs based on the intelligent transportation system are considered in parallel to rule-based and optimization-based EMSs. For each EMS, a comprehensive and detailed review, based on energy management methods or algorithms, summarizes the advanced research results of scholars. The principles and the advantages and disadvantages of different EMSs are expressed using figures and tables.

Aiming at the complex control system of a quadruped robot, a leg structure of a quadruped robot was designed based on mechanism synthesis. The innovativeness of this robot is that it can achieve a special gait driven only by a single motor. Simulation and experimental analysis prove that the mechanism is reasonable, reliable and can meet the requirements of linear walking and climbing. The conclusions of this research will be useful for application in field of single actuated quadruped robots.

Compared with the two traditional intelligent optimization algorithms, the results show that the particle swarm optimization configuration algorithm, based on an improved orthogonal experiment design, has a better optimization effect, and the results are improved to a certain extent. The evaluation indexes of a multi-objective optimization design are often contradictory. The designer needs to compromise and select an appropriate parameter design value.

A family of trigonometric motion programs can be condensed into a general expression, and motion programs with lower peak kinematic values are synthesized with ease. The presented phase angle function makes the formulation of motion programs more simple, and a modified phase angle function is proposed to reduce motion characteristics. The synthesis process and results are clearly presented by illustrative examples.

In order to improve the antiwear performance of the cylinder liner, friction and wear during the running-in process are investigated. Friction and wear tests are designed under different operating conditions, and the coefficient of friction (COF) and surface profile are measured. The influences of load and runtime on the COF and surface morphology are serious, and proper loading can reduce the running-in time. This research can provide support for theoretical research on cylinder liners.

Based on solving the problem of surrounding rock deformation of an engineering geological tunnel, a new support structure composite cantilever support structure is proposed. The numerical calculation and application of the structure are carried out, and it is verified that the composite cantilever support structure can effectively restrain the deformation of surrounding rock, and the appropriate design parameters of the support structure are obtained. It has a certain engineering value.

In this paper, a novel and effective constraint handling method called the individual repairing method is introduced. This method transforms every infeasible point in the search space into a unique corresponding feasible point, so as to ensure the success and effectiveness of the optimization. This is the defining and innovative essence of this study compared with other relevant work. Based on the new constraint handling method, the optimization of path synthesis can be effectively carried out.