This work deals with manufacturing and analysis of orthotropic composite Kagome honeycomb panels. A novel modular mold is proposed to manufacture carbon fiber reinforced composite Kagome honeycombs. The designed mold can be assembled freely to manufacture Kagome honeycombs with different configuration combinations and can realize easy demolding. Furthermore, two typical fiber placement methods are considered during the fabrication process, from which the more effective fiber placement method is determined. Finally, representative volume element method is used to perform homogenization analysis of the Kagome honeycomb panels and to obtain equivalent in-plane and bending stiffness. Finite element analysis using these equivalent properties is conducted and validated against the experimental results of the manufactured composite Kagome honeycomb panels under different loading cases.

Bin NIU ,   Shijie LI   et al.
The manufacture and maintenance of large parts in ships, trains, aircrafts, and so on create an increasing demand for mobile machine tools to perform operations. However, few mobile robots can accommodate the complex environment of industrial plants while performing machining tasks. This study proposes a novel six-legged walking machine tool consisting of a legged mobile robot and a portable parallel kinematic machine tool. The kinematic model of the entire system is presented, and the workspace of different components, including a leg, the body, and the head, is analyzed. A hierarchical motion planning scheme is proposed to take advantage of the large workspace of the legged mobile platform and the high precision of the parallel machine tool. The repeatability of the head motion, body motion, and walking distance is evaluated through experiments, which is 0.11, 1.0, and 3.4 mm, respectively. Finally, an application scenario is shown in which the walking machine tool steps successfully over a 250 mm-high obstacle and drills a hole in an aluminum plate. The experiments prove the rationality of the hierarchical motion planning scheme and demonstrate the extensive potential of the walking machine tool for operations on large parts.

Jimu LIU ,   Yuan TIAN   et al.
In this study, the micro curing residual stresses of carbon fiber-reinforced thermoset polymer (CFRP) composites are evaluated using a multiscale modeling method. A thermochemical coupling model is developed at the macroscale level to obtain the distributions of temperature and degree of cure. Meanwhile, a representative volume element model of the composites is established at the microscale level. By introducing the information from the macroscale perspective, the curing residual stresses are calculated using the microscale model. The evolution of curing residual stresses reveals the interaction mechanism of fiber, matrix, and interphase period during the curing process. Results show that the curing residual stresses mostly present a tensile state in the matrix and a compressive state in the fiber. Furthermore, the curing residual stresses at different locations in the composites are calculated and discussed. Simulation results provide an important guideline for the analysis and design of CFRP composite structures.

Xinyu HUI ,   Yingjie XU   et al.
The human social development saw the formation of five unique civilizations, with the latter forming their own distinctive cultures. China’s traditional culture is its most fundamental ideological weapon for solving problems. The Chinese are good at comprehensive thinking, dialectical thinking, and systematic analysis. These ideological weapons can solve the problems of formal science and technology and create scientific and technological achievements on par with global advanced scale. Ancient China is filled with original scientific and technological achievements, which strongly prove ancient China’s possession of its own science and technology different from that of Western Renaissance. Therefore, a comprehensive understanding of science, technology, experience, and intuition is necessary. The long-held superstition regarding the West, the lack of confidence, self-denial, blind imitation of ideas, and shackles must be thrown away. Only then can we take the road toward an authentic Chinese creative design as we learn from others.

Huijun ZOU ,   Qinghua LIANG   et al.

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