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In order to solve the problem of high complexity and large amount of computation for kinematics of industrial robots, conformal geometric algebra (CGA) is introduced to the construction of kinematics model of industrial robots. In the forward kinematics solving process, the motion expressions of each joint are obtained by using the translation and rotation operators in CGA, and then the pose of the end-effector of the robot is obtained. In the process of solving the inverse kinematics, cross product of the constructed basic geometry is carried out to obtain the position of each joint node, the lines and planes through the joint node are constructed, the inner product is made in the CGA frame to obtain the cosine expression of all joint angles, and then all the solutions of the robot's inverse kinematics are solved. Finally, the MOTOMAN-HP20D 6-DOF industrial robot is used for example calculation, and the accuracy and effectiveness of the algorithm is verified by Matlab/Simulink software, which lays the foundation for the subsequent motion control of the robot.

In order to solve the problem of high complexity and large amount of computation for kinematics of industrial robots, Conformal geometric algebra （CGA） was introduced to the construction of kinematics model of industrial robots. In the forward kinematics solving process, the motion expressions of each joint were obtained by using the translation and rotation operators in CGA, and then the pose of the end-effector of the robot was obtained. In the process of solving the inverse kinematics, cross product of the constructed basic geometry is carried out to obtain the position of each joint node, and then the lines and planes through the joint node are constructed, and the inner product is made in the CGA frame to obtain the cosine expression of all joint angles, and then all the solutions of the robot's inverse kinematics are solved. Finally, the MOTOMAN-HP20D 6-DOF industrial robot was used for example calculation, and the accuracy and effectiveness of the algorithm was verified by Matlab/Simulink, which laid the foundation for the subsequent motion control of the robot.

Driven by the information industry, there is an urgent need for lead-free ceramic materials exhibiting excellent recoverable energy storage density (Wrec) and energy storage efficiency (η) to meet the practical application requirements of pulse power capacitors. Among these, Bi0.5Na0.5TiO3 (BNT) stands out as a highly promising and competitive environmentally-friendly ceramic material due to its exceptional dielectric properties. However, premature polarization saturation and low dielectric breakdown field (Eb) have been major obstacles to its practical application. Herein, the scheelite-structured La2WTiO8 (LWT) is successfully integrated with the perovskite-structured BNT to enhance the energy storage performance (ESPs) of BNT-based ceramics. The obtained results show that LWT doped into BNT matrix destroys the long-term ferroelectric order and effectively promotes the formation of polar nanoregions, which enhance Eb and delay polarization saturation. Ultimately, the optimized composition achieves the expected Wrec (∼6.3 J cm−3) and η (∼78.9%) at 400 kV cm−3 with excellent temperature stability (<9% variation in the temperature range of 20–200 °C) and frequency stability (∼2.8% variation in the frequency range of 1–100 Hz). In addition, a fast discharge performance of t0.9 ∼ 62.6 ns and a high power density of 105.71 MW cm−3 at 200 kV cm−1 are achieved. This work proposes a strategy to obtain high comprehensive ESPs of BNT-based ceramics, offering new prospects for the development of advanced pulse capacitors. [ABSTRACT FROM AUTHOR]

Several iterative finite element methods are analyzed for a steady‐state double‐diffusive natural convection model, which contains the diffusion of temperature and concentration and can simulate heat and mass transfer phenomena. These iterations include the Stokes‐type, Newton‐type, and Oseen‐type iterative methods. Then, based on the uniqueness condition, stability and convergence of these iterative methods are proved for the considered model. Finally, some numerical examples are presented for validating the correctness of the theoretical analysis. [ABSTRACT FROM AUTHOR]

Y2/3Cu3Ti4O12 ceramic is a novel semiconductor with potential applications in electronic devices. However, its resistance drift and surface structure defects limit the application for negative temperature coefficient thermistor devices. A comparative study of solid‐phase and a Pechini processing of Y2/3Cu3Ti4O12 is presented in this paper, in the particular comparative study of stability. The Pechini method is found to be effective in lowering sintering temperature and improving thermal stability (ΔR/R0 < 0.3％) in comparison with solid‐phase method. The origin of the stability deterioration is related to the oxidation state of Cu ions and the migration of sublattice. The Pechini method overcomes stoichiometric ratio deviations and cation vacancy diffusion, thus reducing metal ion segregation in a continuous high‐temperature environment and thereby showing unique insensitivity to oxygen. The important role of the Pechini method in improving thermal stability is revealed, which is expected to be used in the preparation of high stability electron devices. [ABSTRACT FROM AUTHOR]

Copper-based composites have interesting properties and they are widely used in electronics, packaging, and automotive applications. In the present work, the cross-accumulative roll bonding (CARB) process was used to fabricate Cu-based composites with Zn and Brass reinforcing layers. The experimental observations revealed a clear relationship between rolling strain and plastic instabilities including the necking and rupture of reinforcement. However, the grain refinement was observed on Cu, Zn, and Brass layers after seven CARB cycles, indicating the positive impact of rolling rotation on obtaining the ultrafine grains. Better ductility of Brass also resulted in finer grains. This also led to more significant improvement in mechanical properties. During the CARB process, the hardness of Zn and Brass increased from 59 HV and 250 HV to 89 HV and 310 HV, respectively. [ABSTRACT FROM AUTHOR]