Flexible tactile electronic devices are extensively used in the fields of robotics, medical detection, and human-computer interaction. Monitoring contact parameters, including force magnitude, direction, and contact l...
详细信息
Flexible tactile electronic devices are extensively used in the fields of robotics, medical detection, and human-computer interaction. Monitoring contact parameters, including force magnitude, direction, and contact location, is particularly vital for skin-like tactile sensing devices. Herein, a 3D force sensor is designed based on porous structure with deliberately designed Poisson's ratios. A genetic algorithm (GA) optimized back propagation neuronal network (BPNN) model is proposed to support the 3D force decoupling, which can greatly improve the decoupling accuracy. The introduction of the GA-BPNN significantly enhances decoupling accuracy compared to the initial neural network. Micro-porous structures with varied Poisson's ratios are embedded into the sensing unit to achieve better sensibility. Significantly, this study underscores that the decoupling accuracy of the force components along the Z-axis can be further improved by substituting the solid unit with a designed porous structure unit featuring a specific Poisson's ratio in an arrayed 3D force sensor.
Accurate measurement of temperature and salinity is an important foundation for oceanographic research. In this paper, dual fiber interferometers combined with a novel nonlinear decoupling algorithm is studied theoret...
详细信息
Accurate measurement of temperature and salinity is an important foundation for oceanographic research. In this paper, dual fiber interferometers combined with a novel nonlinear decoupling algorithm is studied theoretically for simultaneous measurement of seawater temperature and salinity. The correlation analysis shows that there is not only a quadratic relationship between the position of interference dips and temperature, but also interaction between temperature and salinity. Therefore, the quadratic polynomial surface fitting method, containing the important interaction term, is used to build the relationship between interference dips position and both temperature and salinity. A quadratic polynomial surface-based nonlinear decoupling algorithm is developed, and the deviation of this algorithm are noticeably smaller than that of the commonly used linear decoupling algorithm. This work may offer useful reference for developing practical optical fiber seawater temperature and salinity sensors and establishing decoupling algorithms for other dual-parameter fiber-optic sensors.
A strain-insensitive optical fiber Mach-Zehnder interferometer (MZI) composed of a rectangular micropore and refractive index modification waveguide (WG) is proposed, which realizes simultaneous measurements of seawat...
详细信息
A strain-insensitive optical fiber Mach-Zehnder interferometer (MZI) composed of a rectangular micropore and refractive index modification waveguide (WG) is proposed, which realizes simultaneous measurements of seawater temperature and salinity. The micropore transversely penetrates the single-mode fiber, which is fabricated by ablating part of the cladding and core with the femtosecond laser. The WG is constructed by inscribing successive modified lines in the fiber cladding by laser direct writing technology. The phase difference between interference beams changes with the temperature and salinity variations, which causes the shift of characteristic wavelengths. The maximum response sensitivities are 3.205 nm/degrees C and -2.714 nm/parts per thousand, with resolutions of 0.006 degrees C and 0.007 parts per thousand. To solve the crosstalk problem between these two seawater parameters, a quadratic polynomial surface fitting method is utilized to achieve accurate data decoupling and reduce measurement errors. In addition, the experimental tests show that the compact MZI sensor is insensitive to longitudinal strain, and has good measurement repeatability and stability, which has broad application potential in the dynamic and complex detection of the marine environment.
We propose a projection-based decoupling algorithm for a woofer-tweeter (W-T) adaptive optics system. This algorithm uses the response matrix of woofer deformable mirrors (DM) to construct a slope-based orthogonal bas...
详细信息
We propose a projection-based decoupling algorithm for a woofer-tweeter (W-T) adaptive optics system. This algorithm uses the response matrix of woofer deformable mirrors (DM) to construct a slope-based orthogonal basis, which can be used to distribute different spatial frequency aberrations to the dual DMs. At the same time, to restrain the cross coupling between the dual DMs, the command vector of the tweeter will be projected onto the slope-based orthogonal basis, and then the portion of the tweeter's command vector, which may generate opposite shape with the woofer can be calculated and eliminated accurately. Numerical simulation for this algorithm demonstrates that it can make the woofer and tweeter correct different spatial frequency aberrations simultaneously, and have more practical value compared with the traditional decoupling algorithm. Experimental results for this algorithm are consistent with the simulation results and proved that the cross coupling between the dual DMs can be restrained well for both static and dynamic aberrations. (C) 2018 Society of Photo-Optical Instrumentation Engineers (SPIE)
In this paper, a novel explicit method for decoupling coupled multi-spring systems in the structural dynamic analysis is proposed by ensuring the second-order accuracy in the low-frequency domain. Two parameters mu an...
详细信息
In this paper, a novel explicit method for decoupling coupled multi-spring systems in the structural dynamic analysis is proposed by ensuring the second-order accuracy in the low-frequency domain. Two parameters mu and beta are introduced in this method to flexibly adjust the stability and accuracy properties and suppress the high-frequency spurious vibrations in the solution. Firstly, the standard formulations of this method are derived and its stability and accuracy are analyzed through comparisons with other available state-of-the-art explicit methods in the literature. Then, the performance of this proposed method is specifically evaluated in terms of accuracy, dissipation in the high-frequency domain and computational efficiency, and effectiveness in dealing with nonlinearity through three examples. Finally, a vertical coupled multi-spring system, a train-rail-sleeper-ballast-bridge system, is employed to demonstrate the efficiency and decoupling properties of the proposed method. The presented attractive performance of this method illustrates its advantages in engineering applications. (C) 2018 Elsevier Ltd. All rights reserved.
The measurements of strapdown imaging seeker are based on body coordinate ***'s attitude motion information is contained within the measured body line of sight(LOS)angles,but LOS rates relative to inertial coordin...
详细信息
The measurements of strapdown imaging seeker are based on body coordinate ***'s attitude motion information is contained within the measured body line of sight(LOS)angles,but LOS rates relative to inertial coordinate are needed for the practical guidance ***,strapdown decoupling for measured signal is essential so as to remove the body attitude information from the *** this paper, the decoupling algorithm is proposed and simulation is performed to show the validation of the decoupling algorithm.
A decoupling algorithm, based on mode signal, is proposed for the control of double deformable mirrors (DMs) in a woofer-tweeter adaptive optics system. The algorithm operates as follows: first, based on the orthogona...
详细信息
A decoupling algorithm, based on mode signal, is proposed for the control of double deformable mirrors (DMs) in a woofer-tweeter adaptive optics system. The algorithm operates as follows: first, based on the orthogonality property of Zernike polynomials within the continuous region of the unit circle, we construct the signal vectors of the constrained modes of woofer and tweeter. Subsequently, control matrices for both the woofer and tweeter are generated by employing singular value decomposition and considering the response matrix of DM signal to slope. Finally, the aberration is determined using the measurement results from the Shack-Hartmann wavefront sensor, and the mode signal coefficient vectors of the two DMs are obtained through integration with the leaky integrator. These coefficient vectors are then multiplied by a transition matrix to derive mode signal control vectors for both the woofer and tweeter. Simulation results demonstrate that the proposed algorithm outperforms both the conventional Zernike mode decomposition control algorithm and the projection-based decoupling algorithm. The experiments demonstrate that the algorithm effectively utilizes the compensation capability of the woofer, enabling it to release tweeter stroke for compensating high-order aberrations and achieving superior correction outcomes.
The authors present a decoupling joint probabilistic data association (DJPDA) algorithm by decoupling the JPDA algorithm into separate PDA algorithms. To demonstrate the decoupling idea, they derive a set of complete ...
详细信息
The authors present a decoupling joint probabilistic data association (DJPDA) algorithm by decoupling the JPDA algorithm into separate PDA algorithms. To demonstrate the decoupling idea, they derive a set of complete decoupling PDA equations for two and three targets. Since these equations are impractical for real-time systems and are unavailable for an arbitrary number of targets, an approximate algorithm is given. The proposed decoupling algorithm is evaluated using computer simulation. It is shown that the performance of the DJPDA algorithm is close to that of the JPDA. algorithm but it needs much less computation.
Use of multidisciplinary analysis in reliabilitybased design optimization(RBDO) results in the emergence of the important method of reliability-based multidisciplinary design optimization(RBMDO). To enhance the effici...
详细信息
Use of multidisciplinary analysis in reliabilitybased design optimization(RBDO) results in the emergence of the important method of reliability-based multidisciplinary design optimization(RBMDO). To enhance the efficiency and convergence of the overall solution process,a decoupling algorithm for RBMDO is proposed ***, to decouple the multidisciplinary analysis using the individual disciplinary feasible(IDF) approach, the RBMDO is converted into a conventional form of RBDO. Secondly,the incremental shifting vector(ISV) strategy is adopted to decouple the nested optimization of RBDO into a sequential iteration process composed of design optimization and reliability analysis, thereby improving the efficiency significantly. Finally, the proposed RBMDO method is applied to the design of two actual electronic products: an aerial camera and a car pad. For these two applications, two RBMDO models are created, each containing several finite element models(FEMs) and relatively strong coupling between the involved disciplines. The computational results demonstrate the effectiveness of the proposed method.
The large manipulator outside the space cabin is a multi-degree of freedom actuator for space *** order to realize the automatic control and flexible operation of the space manipulator,a novel spoke structure piezoele...
详细信息
The large manipulator outside the space cabin is a multi-degree of freedom actuator for space *** order to realize the automatic control and flexible operation of the space manipulator,a novel spoke structure piezoelectric six-dimensional force/torque sensor with redundancy ability,high stiffness and good decoupling performance is innovatively *** on the deformation coordination relationship,the redundancy measurement mechanism is *** mathematical models of the sensor with and without branch fault are established *** finite element model is established to verify the feasibility of structure and redundancy measuring principle of the *** on the theoretical analysis and simulation analysis,the prototype of the sensor is *** and dynamic calibration experiments are carried *** actual output voltage signal of the six-dimensional force/torque sensor is collected to establish the equation between the standard input applied load and the actual output voltage *** on ant colony optimized BP algorithm,performance indexes of the sensor with and without branch fault are analyzed *** experimental results show that the spoke piezoelectric sixdimensional force/torque sensor with the eight-point support structure has good accuracy and ***,it has strong decoupling characteristic that can effectively shield the coupling between *** nonlinear errors and maximum interference errors of decoupled data with and without branch faults are less than 1% and 2%,*** natural frequency of the sixdimensional force sensor can reach 2856.45 Hz and has good dynamic *** research content lays a theoretical and experimental foundation for the design,development and application of the new six-dimensional force/torque sensors with ***,it will significantly improve the research level in this field,and provide a strong guarantee for the smoot
暂无评论