Manipulator Trajectory Tracking Based on Kinematics Model Predictive Control

This paper explores the trajectory tracking strategy of a six-axis manipulator based on the kinematics model predictive control. Firstly, the kinematics of the manipulator was analyzed, and modeled mathematically. Next, the pose errors of the end effector were determined against the error parameters involving joints and rods. After that, the pose error model of the end effector was adopted to quantify how much the errors of different parameters affect the location of the manipulator. Finally, the geometric errors of manipulator trajectory were identified by the least squares (LS) method. Experimental results show the effectiveness of our model. The research results provide a reference for the theoretical analysis and application of manipulator trajectory tracking strategy

Cooperative Multiagent Attentional Communication for Large-Scale Task Space

Acknowledgments This work was supported by the Dalian University Research Platform Project Funding: Dalian Wise Information Technology of Med and Health Key Laboratory, the National Natural Science Foundation of China: Research on the stability of multi-surface high-speed unmanned boat formation and the method of cooperative collision avoidance in complex sea conditions, NO.61673084.Peer reviewedPostprintPublisher PD

Mid-infrared dual-rhombic air hole Ge 20 Sb 15 Se 65 chalcogenide photonic crystal fiber with high birefringence and high nonlinearity

We propose a mid-infrared dual-rhombic air hole hexagonal lattice photonic crystal fiber with high birefringence and large nonlinearity based on Ge20Sb15Se65 chalcogenide glass. The properties of birefringence, dispersion, nonlinearity, and confinement loss were investigated in the 3 µm~5 µm mid-infrared range by using the Finite Difference Time Domain (FDTD) method with perfectly matched layer (PML) absorption boundary conditions. The results indicate that for the optimized structural parameters of Λ= 2.0 µm, D= 1.932 µm, d= 0.8 µm, and H= 0.8 µm, an ultrahigh birefringence of 0.041, a very low confinement loss of 0.0013 dB/km (for x-polarization modes) and 0.0342 dB/km (for y-polarization modes), and the maximum nonlinearity coefficient of 4375 w−1km−1 (for x-polarization modes) and 3960 w−1km−1 (for y-polarization modes) were achieved, respectively. The proposed PCF has a lower confinement loss and higher birefringence than an elliptical-hole PCF with the same air-filling fraction. Thus, it will be an excellent candidate for mid-infrared optical fiber sensing, precision optical instruments and nonlinear optics

Novel emerging nano-assisted anti-cancer strategies based on the STING pathway

Activation of simulator of interferon genes (STING), which induces the production of proinflammatory factors and immune effector cell activation, is considered a promising strategy for enhanced anti-cancer intervention. However, several obstacles prevent STING signaling in solid tumors, such as delivered molecules’ rapid degradation, restriction to tumor sites, insufficient intracellular concentrations, and low responsivity. Well-designed, multifunctional nano-formulations have emerged as optimized platforms for STING activation. Recently, a variety of nano-formulations have been developed and used in STING activation, thus facilitating immunotherapy in preclinical and clinical stages. Herein, we summarize recent advances in nanotechnology-based delivery, activation, and application strategies, which have advanced various aspects of immunotherapy. Novel STING agonists and their mechanisms in STING-activation-mediated tumor interventions are highlighted herein, to provide a comprehensive overview and discuss future directions for boosting immunotherapy via STING regulation