A Multiscale Reliability-Based Design Optimization Method for Carbon-Fiber-Reinforced Composite Drive Shafts

Carbon fiber composites,characterized by their high specific strength and low weight,are becoming increasingly crucial in automotive lightweighting.However,current research primarily emphasizes layer count and orientation,often neglecting the potential of microstructural design,constraints in the layup process,and performance reliability.This study,therefore,introduces a multiscale reliability-based design optimization method for carbon fiber-reinforced plastic(CFRP)drive shafts.Initially,parametric modeling of the microscale cell was performed,and its elastic performance parameters were predicted using two homogenization methods,examining the impact of fluctuations in microscale cell parameters on composite material performance.A finite element model of the CFRP drive shaft was then constructed,achieving parameter transfer between microscale and macroscale through Python programming.This enabled an investigation into the influence of both micro and macro design parameters on the CFRP drive shaft’s performance.The Multi-Objective Particle Swarm Optimization(MOPSO)algorithm was enhanced for particle generation and updating strategies,facilitating the resolution of multi-objective reliability optimization problems,including composite material layup process constraints.Case studies demonstrated that this approach leads to over 30%weight reduction in CFRP drive shafts compared to metallic counterparts while satisfying reliability requirements and offering insights for the lightweight design of other vehicle components.

Generating heralded single photons with a switchable orbital angular momentum mode

The orbital angular momentum(OAM) carried by photons defines an infinitely dimensional discrete Hilbert space. With OAM modes, high-dimensional quantum states can be achieved for quantum communication and cryptography. Here we demonstrate a heralded single-photon source with a switchable OAM mode, which consists of a heralded single-photon source and an integrated OAM emitter as the mode converter. As the first step, the heralded single-photon source is based on the dispersion-shifted fiber. In this work, the OAM mode(quantized by topological charge l) carried by the heralded single photon(at fixed wavelength of 1555.75 nm) can be switched within the range of l=3–7 while the mode purity is more than 80%.

Programmable unitary operations for orbital angular momentum encoded states

We have proposed and demonstrated a scalable and efficient scheme for programmable unitary operations in orbital angular momentum(OAM)domain.Based on matrix decomposition into diagonal and Fourier factors,arbitrary matrix operators can be implemented only by diagonal matrices alternately acting on orbital angular momentum domain and azimuthal angle domain,which are linked by Fourier transform.With numerical simulations,unitary matrices with dimensionality of 3×3 are designed and discussed for OAM domain.Meanwhile,the parallelism of our proposed scheme is also presented with two 3×3 matrices.Furthermore,as an alternative to verify our proposal,proof of principle experiments have been performed on path domain with the same matrix decomposition method,in which an average fidelity of 0.97 is evaluated through 80 experimental results with dimensionality of 3×3.