In order to reduce the energy loss and improve the wear resistance of a piston–cylinder pair in an axial piston motor，an optimized tapered piston bore is designed and applied. A fluid–structure interaction numerical model and a new test rig of the friction force of the piston–cylinder pair are developed. Numerical analysis and experimental results show that the optimized tapered-shape piston bore in an axial piston motor can achieve a significant reduction in leakage flow and friction force.

A high-speed wheeled amphibious vehicle was designed and researched based on computational fluid dynamic (CFD) technology. The results were compared with the corresponding test results for verification. CFD is applied to analyze the influence of the wheel flip angle on the resistance performance, and resistance reduction is explained by the change in wake flow-field of the amphibious vehicle. The wheel well was optimized based on our requirement for the vehicle performance on land and water.

Considering its practical engineering applications, a proportional-derivative-based robust controller is designed and applied to a nonlinear robotic system with uncertainty. With error- and model-based features, accurate position tracking can be achieved. The control feedback gain is automatically and iteratively adjusted by learning so that the desired performance of the system is optimized.

In the design and processing of face gears, it is not necessary to accurately express the tooth surface with an equation, since it will be difficult to analyze some of the most important and practical features, such as the induced curvature relationship. In this regard, this paper uses the discrete curvature relationship of a spatial gradient curvature ellipsoid to describe the space meshing surface, and it establishes a set of discrete digital conjugate surface meshing principles.

In this paper, a gait analysis algorithm for a lower limb rehabilitation robot is proposed. The algorithm realizes the division of gait temporal information and the design of a gait spatiotemporal parameter algorithm based on lidar. A spatial parameter-splicing algorithm based on a time series is proposed, which effectively reduces the influence of errors on gait parameters. Based on the gait algorithm, aiming at real-time algorithm performance, a dynamic window method is proposed.

Aiming to address the noise reduction problem of two-speed automatic transmission of a pure electric vehicle, in the study, through the vehicle noise test, the noise source and noise cause were analyzed and the gear modification optimization method and the gear modification effect were explored.

This paper proposes a robot following method to follow the sewing action of human upper limbs. The purpose of this paper is to demonstrate that robots can assist workers in the future. Compared with the visual servo method, the accuracy is much improved.

The main contribution of this work is to propose a multi-objective optimization design method in terms of factor analysis, a back-propagation (BP) neural network, principal component analysis (PCA), and a particle swarm optimization (PSO) algorithm to achieve optimal comprehensive performance of a mechanism. The computational cost of the proposed approach was reduced by 96.95 % compared with the PSO algorithm, and the comprehensive performance increased by 118.92 %.

A 3-degrees-of-freedom cable-driven hybrid 3D-printing mechanism is developed to overcome the high inertia of rigid printing mechanisms and the difficulties of mechanism analysis, a vector analysis method is proposed, and a prescribed-performance controller is designed to improve the stability and motion accuracy of the end-effector. A physical simulation environment and a prototype of the mechanisms are developed. Finally, the clay-printing experiment results show the mechanism to be feasible.

This paper deals with the construction of a novel family of multimode deployable mechanisms. By connecting many identical threefold-symmetric Bricard-like mechanisms, a multimode deployable arch is proposed for the first time, which can switch between the scissor-like deployable mode and the arch deformable mode through the transition configuration. Then, new multimode center-driven deployable mechanisms can be obtained by connecting three and six multimode deployable arches.

Resource coordination and allocation strategies are proposed to reduce the probability of failure by aiming at the problem that the robot cannot continue to work after joint failure. Taking the planar 4R redundant robot as an example, the algorithm control is compared. Based on reasonable modeling and physical verification, the results show that the method of optimal resource coordination and allocation is effective.

A cable-driven body weight support gait training robot (C-BWSGTR) was designed to help provide patients with partial body weight support and a stable walking driving force to assist gait rehabilitation training. Overall configuration, kinematic modeling, and motion planning were carried out, and a position servo composite control strategy was designed. Simulation analysis and the prototype experiment verified that the designed control strategy met the requirements of the system.

A wearable ankle assisted robot is developed to meet the demand for ankle assistance during human walking. The active energy storage mechanism in the robot can realize the storage and release of energy and realize the application of a low-power motor to provide large assisted force. The experimental results show that the net metabolic cost of the participants is reduced by averages of 5.30 %, 5.67 %, and 4.84 % with 0, 4, and 8 kg loads respectively.

A novel method is presented for efficiently analyzing the reliability of engineering components and systems with highly nonlinear complex limit state functions. To demonstrate the effectiveness of the proposed method, four examples involving mathematical functions and mechanical problems are solved. The findings demonstrate that while maintaining high-precision reliability results, the proposed method significantly reduces the number of evaluations of the limit state function.

Surface topography is an important feature to evaluate the surface quality of components, as is the stress concentration caused by the random surface topography. This paper proposes a numerical analysis method to study surface stress concentration factor (SCF) and relative stress gradient (RSG) for notched round-bar specimens. The surface SCF and RSG increased with increasing surface roughness, and a linear function relationship of surface roughness with surface SCF and RSG was established.

The development of bionic skin has always been a challenging scientific research problem. A novel experimental method is proposed for investigating fingertip friction perception characteristics. The results show that the tactile perception accuracy can be improved by changing the surface texture and lubrication conditions. The method can provide peer experience for revealing tactile perception mechanisms and can also provide theoretical guidance for the research of bionic skin.

This paper proposes a gear injury equilibrium oriented self-adjusted shifting strategy (EASS) to equalize injury values across gears to ensure consistency, alongside an adaptive nonsingular global fast-terminal sliding-mode control for synchronizer control. The EASS allowed ongoing injury to gears to be more consistent, avoiding focused injury on a single gear in the transmission while allowing other gears to take relatively small amounts of injury, thus affecting the transmission life.

First, a jumping leg mechanism that imitates a goat's hindlimb is proposed. Second, the kinematics of a goat-inspired jumping leg is analyzed and the jumping trajectory planning is conducted with cubic polynomial curves to guarantee smoothness in the jumping process. Finally, experiments on the goat-inspired jumping leg are conducted to test its jumping performance and to verify the correctness of the kinematic model and the jumping trajectory planning method of the leg.

To enable the control system to provide minimal assistance and apply different rehabilitation stages according to the subject's performance, this paper proposes a motion-trend-based assistance control strategy. The preliminary experimental results demonstrate that the proposed control strategy works well to quickly adjust the assistance to the subject's motor performance and quickly reduce the assistance when the subject tends to actively participate in the exercise.

The sensitivity analysis is investigated to solve multi-objective optimization problems with cell mapping in high-dimensional parameter space. A post-processing algorithm is introduced to help choose control parameters from the Pareto set. An optimal-sliding-mode combined-control strategy is proposed to solve global optimal tracking control problems for a MIMO system. The schemes proposed are applied successfully in the control optimization for an antenna servo system on a disturbed carrier.

In order to enhance the accuracy of predicting grinding forces during the surface grinding of knife-like tool blades, a novel analytical-regression correction method has been introduced. This method analyzes the changing contact line between the grinding wheel and the tool and refines the variable edge-width grinding force model through the use of exponential coefficients in a regression analysis. This significantly improves the predictive accuracy of the model.

Gyro-pendulums are usually used to stabilize the firing of guns on warships or tanks or to navigate cars and aircraft. The stability of the gyro-pendulum is a classical problem in dynamics and control. Moreover, the bounded noise is real in nature, which affects the operation of the dynamical system and even its stability. Our research results on the stochastic stability of gyro-pendulum systems have a good guiding effect for the actual operation of the system and engineering application value.

The presence of initial residual stress is a major contributor to machining distortion. To control machining distortion, the transition structure before the finishing stage is optimized in this paper. The first step is to create a machining distortion analysis model for long beam parts based on initial residual stress. The transition structure's topology optimization model is then established. Finally, a verification case is used. The proposed model is verified by simulation and experiments.

This paper presents a new method to design a new mechanism with fewer moving joints and greater bearing capacity. These machinery-manufacturing, parts-processing, and other fields have a wide range of application prospects.