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Driven-measurement pattern affects image reconstruction quality of Electrical Impedance Tomography (EIT). In this paper, optimal pattern selection approach based on machine learning is proposed. It converts the problem of driven-measurement pattern optimization to pattern recognition. It is simple, effective and fast. The selected optimal pattern is used for image reconstruction, which is aiming at an improvement. Support Vector Machines (SVM) is used to select the optimal pattern. Firstly, pattern candidates are generated. The optimal pattern is considered to be selected from them. Secondly, optimal pattern selection approach is introduced. SVM with estimated conductivity distribution as features is used for pattern recognition. Thirdly, the proposed approach is verified by both simulation and experiment. Average imaging correlation coefficient (ICC) of the reconstructed images for simulation models is improved 7.6163% from 0.7891 to 0.8492. In experiment, average ICC is improved 2.9439% from 0.7541 to 0.7763. [ABSTRACT FROM AUTHOR]

In this paper, the vibration characteristics of the designed hybrid truss-type movable heavy-load pouring robot (pouring robot) and the pose control of the parallel working arm are studied. The dynamic-static method is used to simplify the truss and parallel working arm of the pouring robot into a forced vibration system composed of spring, damping, and mass body, based on this the 9-degree-of-freedom vibration equation of the pouring robot is established, the analysis of the amplitude–frequency characteristics shows that the four input vibrations of the pavement have basically the same influence on the ladle, which will cause the ladle to resonate. Kane's method is used to establish the lower mobility dynamic equation of the parallel working arm, the Jacobian matrix of force-driven and torque-driven coupling are given. Based on the vibration characteristics of the pouring robot and the dynamic model of the parallel working arm, an adaptive sliding mode control method with radial basis function neural network compensator and Newton–Euler iterative estimator are proposed to realize the pose control of the ladle, the Lyapunov theorem proves the stability of the control method, the simulation results show that adaptive sliding mode control has better control performance, faster response speed, higher convergence accuracy, and better robustness than traditional sliding mode control algorithm. The paper provides a reference and research basis for the suppression of ladle vibration when the pouring robot is transferred, which is affected by the road roughness. [ABSTRACT FROM AUTHOR]

A six-axis vibration isolation system is essential to high-precision space systems for attenuating vibrations on precise instruments. The kinematic optimal design is researched for the space six-axis vibration isolator via Stewart mechanism. Jacobian matrix is the basis of the kinematic performance index. However, the conventional Jacobian matrix is not usually dimensionally homogeneous due to the inhomogeneous physical units, caused by the different mathematical representations of the rotation and translation. In this paper, we propose a dual quaternion approach to derive the dimensionally homogeneous Jacobian matrix of a general six-axis parallel mechanism. Two quaternions are used to parameterize the rotation and translation of the platform. The dimensionally scaling factor for the generalized Jacobian matrix is defined as the ratio of the norms of the two quaternions. The dimensionally homogenous Jacobian matrix is then obtained and applied to the optimal design of the six-axis vibration isolator. The performance index of isotropy is considered to make the isolator minimum kinematic coupling in its working configuration. [ABSTRACT FROM AUTHOR]