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In order to improve the structural performance of the out-of-pipe pipe-climbing robot, the out-of-pipe pipe-climbing robot is optimized. The structure and size of the robot was optimized. Static and modal analyses were then performed on key robot components and ANSYS was used for topology optimization. It was found the weight of the optimized frame and clamping arm were respectively reduced by 24 % and 20 %, and the maximum stress was respectively reduced by 46 % and 20 %.

A terminal sliding mode controller is used to design the controller, and a radial basis function neural network method is used for adaptive approximation of system parameters. In order to eliminate chattering, a fuzzy algorithm is designed for fuzzy control of control gain. The simulation verified that the controller designed in this paper can effectively carry out trajectory tracking and the lateral control of electric vehicles and eliminate chattering to a certain extent.

To lower the frequency of suspending and calibrating a robot manipulator, an innovative device for enlarging the allowed position error is proposed in this study. It is a purely mechanical device without any electrical sensors. A trigger mechanism with a spring is used to replace a touch sensor and an actuator, and a six-bar linkage delivers the bolt to the hole that the trigger mechanism detected for it to be screwed in. The functions of the new device are verified through prototype testing.

A novel hollow-ring permanent magnet brake integrated in robot joints is proposed, which allows the brake to require much less axial space and provides more than 1.5 times braking torque for the same volume as the conventional electromagnetic-spring friction brake. A coupled dynamics model of the proposed brake is developed from machine-electric-magnetic aspects. The 3D model of the brake is simulated through finite-element software. The theoretical models are verified through experiments.

This paper proposes a novel EMG-based motion compensation controller in active training control to improve patients’ active participation. After proposing an upper limb rehabilitation robot and doing the path plan, the EMG compensation experiments and the active training control experiment are done to prove that the method can control the robot in providing auxiliary force according to patients’ motion intents. The robot can guide the patients in implementing reference tasks in active training.

This paper proposes a novel origami-based deployable mechanism, which can be deployed from the cuboid folded configuration to the cylindrical configuration. In comparison with the reported deployable mechanism composed of links, the hinge arrangement of the proposed mechanism makes it easier to achieve a higher stiffness. It is applied to the design of a parabolic cylindrical deployable antenna, and a scaled prototype of the antenna is constructed to verify the feasibility of the design.

The speed of autonomous vehicles will have a significant influence on the safety and comfort of driving. When the autonomous vehicle passes through the consecutive speed control humps, how to automatically select the most appropriate speed has become a practical research subject. The paper chooses the genetic algorithm to build a multi-objective optimization model and then designs and carries out the solution process of the multi-objective optimization problem for the vehicle.

To improve the stiffness performance of the parallel mechanism, this paper proposes a novel 3-DOF redundantly actuated 2RPU-2SPR parallel mechanism. What is more, the stiffness model of the parallel mechanism is deduced and the accuracy of the stiffness model is verified through finite-element analysis. Finally, the simulation experiment results demonstrate that the redundantly actuated parallel mechanism has better stiffness performance compared to a traditional 2RPU-SPR parallel mechanism.

China is one of the first countries that produced textiles in the world. It has designed and developed a variety of equipment to facilitate textile work. However, due to unclear descriptions in the records and illustrations, a variety of designs with different structures may have been produced. This paper briefly analyzes the structures of textile mechanisms and explores the degree of freedom of the mechanisms to find feasible designs in line with functional requirements.

Under the condition of high temperature, high pressure and severe friction, the micro-texture hole or groove will be filled with chips quickly and lose its function. The texture with a larger aperture is made on the tool rake face, which is connected with the internal cooling hole so as to achieve the functions of cooling, lubricating, reducing friction, changing chip state, reducing cutting force, prolonging tool life and reducing production cost during rough machining.

To investigate the effect of the gear transmission system on the dynamic responses of the metro vehicle driving system, a vertical–longitudinal dynamics, model which considers the frame-hung traction motor and gearbox, is established and is validated to be reliable by comparing the simulation results and field test results in both time domain and time–frequency domain in this paper. Compared to wheelset, the gear mesh force has a greater effect on the force state of traction motor and gearbox.

We designed a motion controller through deep reinforcement learning. The laparoscopic visual field image is input to the controller, and the controller outputs the joint motion of the laparoscopic arm to adjust the visual field. During the movement of the surgical instrument in different trajectories, the controller keeps the surgical instrument in an appropriate position in the visual field. It proves that the method is widely effective and can meet the needs of doctors during surgery.

This paper use the topological characteristic constants for isomorphism identification, such as the power value sequence (PVS), least distance matrix sequence (LDMS), and loop number (LN). The fourth PVS, the LDMS, and the LN are compared and arranged in descending order, forming a strong complementary chain. Our results show that solving the problem of the isomorphism identification of the kinematic chain (KC) based on graph theory definition has no advantage in efficiency.

In this paper, the traditional bee colony algorithm is improved, and its roundness error evaluation method is improved. For the roundness profile data of the part, the improved bee colony algorithm is used to determine the position and size of the circle. In order to improve the efficiency of the algorithm, the local search region of the population initialization is determined according to the definition of roundness error. The evaluation accuracy of this algorithm is better than common ones.

Robotic ultrasonic scanning needs to apply an appropriate force for a long time during the acquisition process. Excessive contact force may lead to deformation and even hurt the patient, while insufficient force would lead to poor image quality. We proposed a varying rate hybrid position–impedance control strategy, which can partly play the role of an ultrasound sonographer and serve as a medical assistant to reduce their workload.

The creation method of a 1 degree of freedom double plant carrier gear train (DPGT) transplanting mechanism was proposed based on the functional constraints. Within the eight components of the DPGT, the automatic creation of a transplanting mechanism was realized. A total of 528 DPGTs, which are suitable for transplanting, including 3 five-bar, 13 six-bar, 92 seven-bar, and 420 eight-bar configurations, were obtained for the first time.

The epicyclic gear train (EGT) is a gear transmission mechanism. When the number of designed structures is increasing and structures are becoming ever more complex, manual screening is very difficult. Therefore, scholars are committed to developing an algorithm that can distinguish repetitive structures. In this paper, we use a method to transform the structural information of EGT into a matrix and extract the hidden information in the matrix to judge whether there is a repeated structure.

Space deployable antenna is a new type of space structure, and one of the key payloads of spacecraft, which is widely used in mobile communication, navigation and remote sensing, deep space exploration, military reconnaissance, and other fields of science and technology and national defense. Aiming at the urgent need for the development of space deployable antenna with large aperture and a high storage rate, a new configuration of a multifold rib modular deployable antenna mechanism is proposed.

An analytical solution for designing the optimal parameters of dynamic vibration absorbers attached to the damped main system is found to be difficult and complicated. In this paper, the adaptive multiswarm particle swarm optimization is applied to parameter optimization, and the numerical solutions of the system are given for the damped main system under sinusoidal force excitation.

To date, most underwater manipulators have been rigid-link structures with a small number of degrees of freedom and have been unable to perform well in confined spaces. Due to their high dexterity and good adaptability to different environments, snake-like manipulators have strong potential for use in complex underwater applications. In this study, a tip-following algorithm is presented to weave through confined and hazardous spaces along a defined path with high efficiency.

A new measurement method for the dynamical response of a marine propeller shaft with lower cost, simple maintenance and high accuracy is proposed. The shaft vibration predicted from the vibration signals of the bearings is easy to measure. The convolutional neural network can fit the nonlinear relationship between the vibration signals of the bearing and propeller shaft.

Due to the high hardness of alumina ceramics, the gap in magnetorheological polishing efficiency is very low. The three-point magnetorheological polishing method is designed, which has a strong magnetic field generator and pressure polishing characteristics. The surface microstructure and surface quality of the polished alumina ceramics under different process parameters were studied, and the optimal process parameters were obtained by analysis.

A performance analysis of the PFDV using a steering mechanism (^SMHPTS_PFDV) and wind turbine power development system using a hydraulic system with PFDV (^WTHPTS_PFDV) is conducted. Dynamic modeling and analysis of the ^SMHPTS_PFDV and ^WTHPTS_PFDV systems is presented. We find that the power and energy loss through the PFDV is higher when it is connected with the dual loads for performing dual functions compared to the other hydraulic drive system used in wind turbines to obtain stable output.

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.