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This paper presents a novel method for interpolation design that ensures the continuity of a velocity profile and satisfies a specified corner tolerance constraint. The method uses an S-shaped profile to generate trajectories for each line segment in the task space. The velocity profiles of each segment are overlapped to control the smoothness of the corners and reduce the cycle time. This study defined an overlapping time parameter that is associated with the corner tolerance and the cycle time. Moreover, a corner tolerance constraint equation was derived that can allow for a given tolerance to be satisfied. This constraint equation enables the use of the proposed velocity profile overlap (VPO) method to specify corner tolerances for each corner of the trajectory. The proposed method was compared against the conventional acceleration/deceleration after interpolation (ADAI) method. The results demonstrate that the proposed VPO method can achieve higher accuracy and lower cycle time than the ADAI method. [ABSTRACT FROM AUTHOR]

A dynamic model is developed to analyze the characteristics of a bimodal ultrasonic motor.

This paper presents an optimization algorithm for tuning the interpolation parameters of computer numerical control (CNC) controllers; it operates by considering multiple objective functions, namely, contour errors, the machining time (MT), and vibrations. The position commands, position errors, and vibration signals from 1024 experiments were considered in the designed trajectory. The experimental data—the maximum contour error (MCoE), MT, and corner vibration (CVib)—were analyzed to compute the performance index. A backpropagation neural network (BPNN) with 20 hidden layers was applied to predict the performance index. The correlation coefficients for the predicted values and experimental results for the MCoE, MT, and CVib based on the validation data were 0.9984, 0.9998, and 0.9354, respectively. The high correlation coefficients highlight the accuracy of the model for designing the interpolation parameter. After the BPNN model was developed, a genetic algorithm (GA) was adopted to determine the optimized parameters of the interpolation under different weighting of the performance index. A weighted sum approach involving the objective function was employed to determine the optimized interpolation parameters in the GA. Thus, operators can judge the feasibility of the interpolation parameter for various weighting settings. Finally, a mixed path was selected to verify the proposed algorithm. [ABSTRACT FROM AUTHOR]

vA generalized model that integrates the Navier- Stokes equation and coupling-of-modes (COM) model for biosensing SAW devices is developed in this paper. The SAW device is separated into three regions: interdigital transducer (IDT), substrate (delay line), and sensing regions. To evaluate the effects of metal thickness, mass loading caused by bioreaction, and different viscous fluid loading, the sensing region is further divided into three layers: piezoelectric substrate, metal layer, and fluid layer. In contrast to the conventional study, which is focused on the change of phase velocity, this model can evaluate the insertion loss and phase shifts under different sensing conditions. It can be shown that the integration of the COM model can provide guidelines for designing the bio-sensing device such as choosing the proper number of IDT, the width of the overlap, and the thickness of the metal layer. Furthermore, the generalized model can be utilized to evaluate the optimal thickness of the metal layer to achieve the maximum sensitivity. [ABSTRACT FROM PUBLISHER]