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For the problem of the rotor position estimation and control accuracy of permanent magnet synchronous motor (PMSM), this paper proposes a PMSM sensorless based on radial basis function (RBF) neural network optimized Automatic disturbance rejection control (RBF-ADRC) and strong tracking filter (STF) improved square root generalized fifth-order cubature Kalman filter (SGHCKF-STF). The Automatic disturbance rejection control (ADRC) has strong robustness, but there are many parameters and difficult to adjust. Now we use RBF neural network to adjust the parameters in ADRC online so as to improve the robustness and anti-disturbance ability. In order to improve the estimation accuracy of rotor position and speed, the orthogonal triangle (QR) decomposition and STF are introduced on the basis of the generalized fifth-order cubature Kalman filter (GHCKF) to design the SGHCKF-STF algorithm that not only ensure the non-positive nature of the covariance matrix but also improve the ability to cope with sudden changes in state during the filtering process. Experimental results show that the combination of RBF-ADRC and SGHCKF-STF improve the sensorless control effect of the PMSM to some extent. [ABSTRACT FROM AUTHOR]

In order to give full play of the advantages of error accumulated small and fast running speed of the high speed Delta robot,the research of bar optimization for the Delta robot is need. Based on establishing the kinematics and dynamics of rigid body model of the system,the global dexterity and the shock vibration function of driving arm are defined,according to the actual work requirements of the Delta robot,the work trajectory is planned. By using MATLAB genetic algorithm toolbox,respectively with dexterity and shock and vibration function as fitness function,the optimal solution of global is got. Then,taking the obtained optimal solution as the upper and lower bounds,by using the weight factor transformation method,the multi- objective optimization of dexterity and shock vibration function is transformed into a single objective optimization,then according to the above method,a set of meet the scale parameter optimization objectives are synthesized,a reference for the Delta robot structure optimization design is provided.

Lightweight Delta robot is typical high-speed and high-precision industrial parallel robot. However, under high-speed condition, because of the lightweight components, it will inevitably lead to the vibration of Delta robot, which reduces the position accuracy and positioning efficiency. To solve this problem comprehensively, this article considers the process vibration and residual vibration of Delta robot, and the intelligent shaping vibration suppression control system is designed by using trajectory planning method of improved trapezoidal mode, shaping control method, and fast terminal sliding mode controller, and the detailed experimental analysis is carried out. The experimental results show that the proposed intelligent shaping vibration suppression control method can well suppress the process vibration and residual vibration of Delta robot, which can effectively improve the operation stability, work efficiency, and position accuracy of Delta robot. [ABSTRACT FROM AUTHOR]

Abstract: A gas chromatography–tandem mass spectrometry method was developed and validated to simultaneously determine boscalid and fludioxonil in grape and soil samples. These samples were extracted with 10 mL of acetonitrile and purified using a mixed primary secondary amine/octadecylsilane sorbent. The method showed good linearity (R2 > 0.99) in the calibration range 0.005–2 μg/mL for both pesticides. The limits of detection and quantification for the two analytes in grape and soil were 0.006 and 0.02 mg/kg, respectively. Fungicide recoveries in grape and soil were 81.18–92.11% for boscalid and 82.73–97.67% for fludioxonil with relative standard deviations of 1.31–10.31%. The established method was successfully applied to the residual analysis of boscalid and fludioxonil in real grape and soil samples. The terminal residue concentrations of boscalid and fludioxonil in grape samples collected from Anhui and Guizhou were <5 mg/kg (the maximum residue limit set by China) 7 days after the last application and 1 mg/kg (the maximum residue limit set by USA) 14 days after the last application. These results could provide guidance for the proper and safe use of boscalid and fludioxonil in grape and help the Chinese government to establish an MRL for fludioxonil in grape. [ABSTRACT FROM AUTHOR]

Abstract: A liquid chromatography–electrospray ionization tandem mass spectrometry method was developed for simple and accurate detection of the fungicides difenoconazole, propiconazole and pyraclostrobin in peppers and soil. Three fungicides residues were extracted from samples by acetonitrile and cleaned up by dispersive solid‐phase extraction before instrumental analysis. The accuracy and precision of the method were evaluated by conducting an intra‐ and inter‐day recovery experiment. The limits of quantification and detection of difenoconazole, propiconazole and pyraclostrobin in pepper and soil were 0.005 and 0.0015 mg/kg, respectively. The recoveries were investigated by spiking pepper and soil at three levels, and were found to be in the ranges 79.62–103.15% for difenoconazole, 85.94–103.35% for propiconazole and 80.14–97.69% for pyraclostrobin, with relative standard deviations <6.5%. Field experiments were conducted in three locations in China. The half‐lives of difenoconazole, propiconazole and pyraclostrobin were 5.3–11.5 days in peppers and 6.1–32.5 days in soil. At harvest, pepper samples were found to contain difenoconazole, propiconazole and pyraclostrobin well below the maximum residue limits of European Union at the interval of 21 days after last application following the recommended dosage. [ABSTRACT FROM AUTHOR]

For the economical and practical parallel robot, there exists joint clearance in its mechanical structure, and the effect of joint clearance on the position precision of the moving platform and the vibration characteristics of the system can not be ignored. In order to analyze the problem, taking Delta robot as the study object, this paper puts forward a new thought that studies the elastic dynamic model with joint clearance and the vibration characteristics of the system. In the process of analysis, knowing that the joint clearance changes with the change of the robot motion state, which is random, the mathematical statistics principle is used innovatively to analyze the kinematics of the branched chain of Delta robot with joint clearance, and the mathematical expectation of joint clearance vector's probability density in the joint coordinate system is used to express joint clearance's numerical value quantitatively before the collision between shaft and shaft sleeve. Then, because the joint clearance is narrow, ignore the acceleration inertia force of the shaft in shaft sleeve, and only consider the collision force and the friction when shaft and sleeve collide. The probability that the shaft hits arbitrary point on the inner wall of the shaft sleeve is the same and obeys the normal distribution, and on the basis of this theory, combining with the Lankarani-Nikravesh collision contact force model and the Coulomb friction model with dynamic correction coefficient, the generalized collision force of joint clearance is studied. By using the finite element theory and the Lagrange equation, fully considering the active arm and the driven arm's spatial dynamic characteristics and motion coordination, the Delta robot system's elastic dynamic model is established. Based on the definition of bar virtual length, the generalized collision force produced by joint space is combined with the elastic dynamics model, the Delta robot elastic dynamic model with joint clearance is established. The system clearance elastic dynamic model is highly nonlinear time varying equation group, and for the characteristics of the equation group, the time discretization method is used to solve the problem, by using the Newmark algorithm with high stability, accuracy and computational efficiency. Then, with the aid of the FARO laser tracker, the clearance elastic dynamic model is verified, and the vibration characteristics of the Delta robot is analyzed by using the hammer impulse method and the simulation of the Workbench software. Experimental results show that the moving trajectory of the center point of the moving platform when considering the joint clearance is closer to the experimental results than that without the consideration of joint clearance. Then, the rationality and correctness of the clearance elastic dynamic model are verified, and the relative errors between theoretical and experimental values of the non zero natural frequency of the first 2 orders are 3.544% and 12.026%, respectively. The two results are very close, which also indirectly proves the correctness of the theoretical derivation of the clearance elastic dynamic model. In addition, from the simulation results it can be found that the 3 groups of subordinate moving arms are the weakest link in the whole Delta robot system. The study can provide a reference for economical and practical parallel robot's position error compensation and system vibration reduction optimization. [ABSTRACT FROM AUTHOR]