Thermal stress simulation analysis of aerospace optical fibers and connectors and related extensions to high-speed railway area

Aerospace optical cables and fiber-optic connectors have numerous advantages(e.g.,low loss,wide transmission frequency band,large capacity,light weight,and excellent resistance to electromagnetic interference).They can achieve optical communication interconnections and high-speed bidirectional data transmission between optical terminals and photodetectors in space,ensuring the stability and reliability of data transmission during spacecraft operations in orbit.They have become essential components in high-speed networking and optically interconnected communications for spacecrafts.Thermal stress simulation analysis is important for evaluating the temperature stress concentration phenomenon resulting from temperature fluctuations,temperature gradients,and other factors in aerospace optical cables and connectors under the combined effects of extreme temperatures and vacuum environments.Considering this,advanced optical communication technology has been widely used in high-speed railway communication networks to transmit safe,stable and reliable signals,as high-speed railway optical communication in special areas with extreme climates,such as cold and high-temperature regions,requires high-reliability optical cables and connectors.Therefore,based on the finite element method,comprehensive comparisons were made between the thermal distributions of aerospace optical cables and J599III fiber optic connectors under different conditions,providing a theoretical basis for evaluating the performance of aerospace optical cables and connectors in space environments and meanwhile building a technical foundation for potential optical communication applications in the field of high-speed railways.

Single-event-camera-based 3D trajectory measurement method for high-speed moving targets

High-speed target three-dimensional[3D]trajectory and velocity measurement methods have important uses in many fields,including explosive debris and rotating specimen trajectory tracking.The conventional approach uses a binocular system with two high-speed cameras to capture the target’s 3D motion information.Hardware cost for the conventional approach is high,and accurately triggering several high-speed cameras is difficult.Event-based cameras have recently received considerable attention due to advantages in dynamic range,temporal resolution,and power consumption.To address problems of camera synchronization difficulties,data redundancy,and motion blur in high-speed target 3D trajectory measurement,this Letter proposes a 3D trajectory measurement method based on a single-event camera and a four-mirror adaptor.The 3D trajectory and velocity of a particle flight process and a marker on a rotating disc were measured with the proposed method,and the results show that the proposed method can monitor the operational state of high-speed flying and rotating objects at a very low hardware cost.