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Helicopters are easy to hit by hard objects during operation, harming pilots. So, we want to provide some technical references for the safe operation of helicopters. What are the factors that affect the safety? Then we analyze how to control this factor through simulation and specific experiments and observe the vibration of the equipment. Finally, results show that the stability of the equipment can be enhanced by designing a certain device to adjust the influencing factors.

This research provides a topology optimization method for thermal structures considering design-dependent convection boundaries. The effectiveness of the proposed method is illustrated using cases with reasonable configurations under complex thermal boundary conditions.

Humanoid robots are stepping into the social environment. However, smooth and safe operation is still a challenge. Faults in robotics, whether mechanical or electrical, are still inevitable. In this work, we present a fault-tolerant scheme for a humanoid robotic arm, to minimize the damage if a joint fails during normal operation or during human–robot interaction or cooperation.

A double-layer ring truss deployable antenna mechanism is proposed, which is connected by a scissor-like structure. The degrees of freedom, six-dimensional velocity, and acceleration are calculated using spiral theory, and the dynamic model is established. Simulation software is used to verify the simulation, and the prototype is made at a reduced scale. Because the satellite antenna is very important, we decided to study the supporting frame.

In this study, magnetorheological finishing was used to polish the surface of a 316L stainless steel sample formed by powder bed laser melting. After polishing, the pits and scratches on the surface of 316L stainless steel sample disappear. Thus, the method could realize nano-machining, and it has great polishing potential.

Overconstrained linkages always need fewer links to realize complex motion in a 3D space and are supposed to be great for constructing large deployable structures. However, the strict geometric conditions are hard to use in a complicated 3D environment. In this study, joint clearance is actively introduced to improve the adaptivity of the linkages (with an example given). This work is significant for improving the application of overconstrained linkages in a complicated environment.

This paper presents a novel soft bionic elbow exoskeleton based on shape metal alloy (SMA) actuators (Sobee-SMA). The exoskeleton adopts a bionic design, combining active deformation material SMA and high elastic material rubber band to simulate the contraction and relaxation of the elbow skeletal muscle. According to the static analysis of the human–exoskeleton coupling model and experiments, the exoskeleton provides elbow-assisted motion and ensures the safety of the thermal heating process.

In this article, the composite synchronization of three inductor motors with a circular distribution by a fuzzy PID (proportional–integral–derivative) method in a vibration system is investigated. A fuzzy PID method is proposed, based on a master–slave strategy. The stability analysis, based on the Lyapunov theorem of the controlling method, is certified. The phase differences of self-synchronization and controlled synchronization are measured and compared from simulation and experiment results.

A new method to solve the motion generation problem of a spherical four-bar crank slider rigid-body guidance mechanism is introduced. According to the amplitude and phase of the position output and direction output of the mechanism, the method of establishing the mechanism output characteristic database is given. Then the solution method of size parameters is given. According to the database and solution method, the motion generation is realized.

A reconfigurable multi-link mechanism is proposed, and based on the multi-link mechanism and the roller fingertip structure, an end effector is designed to manipulate geometric soft fabrics. The working principle of the reconfigurable multi-link mechanism, the structure and grasping mode of the end effector are introduced in detail, and the kinematics analysis and simulation of the end effector are carried out.

Lightweight and stable continuum robot design is a challenge. We propose a 65 g continuum robot formed using cruciform-arranged elastic sheets. It has low coupling, better bending characteristics in the deformation direction, and a large load capacity in the non-deformation direction, providing a new configuration for lightweight and dexterous continuum robots. Its kinematics model accuracy is experimentally verified. Nucleic acid detection demonstration proves its dexterity and adaptability.

Traditional path-planning algorithms for bending robots are often a sequence of multiple line segments and an unsmoothed curve, which causes a discontinuous robot motion. A smooth path can ensure continuous motion. We propose an improved artificial potential field-based path-planning method based on the idea of a rapidly exploring random tree (RRT) algorithm, reducing the length of and smoothing the path, thus solving the path-planning problem of a multi-degrees-of-freedom (DOF) bending robot.

In this paper, we propose a piezoelectric energy harvester for human body motion. Based on an analysis of dynamics equations, we find that such a piezoelectric energy harvester performs very well, especially at lower frequencies. We suggest that the piezoelectric beam of an energy harvester subjected to multi-excitation with different modes of motion is quite suitable for harvesting energy from human body motions.

Automatic lane-change maneuvers and obstacle-avoidance systems can effectively reduce the incidence of vehicle collision accidents. However, the trajectory-tracking accuracy and response speed will be affected by both external and internal factors. To solve the above problems, a control strategy is proposed. The strategy proposed in this work can not only effectively improve the trajectory tracking performance under road excitation but also significantly improve the ride comfort.

Optimizing the structure of the dust extraction port is the key to effectively improving the operational performance of the sweeper. CFD methods are used to analyze the influence of parameters on the sweeping effect in combination with a gas–solid two-phase flow model. The data set is established with the help of orthogonal test methods, and a BP neural network is used to fit the structural parameters and evaluation indexes.