Coating Extrusion Characteristics of Thin-Walled Tubes for Catheters Using Thermoplastic Elastomer.

During the production of medical thin-walled tubes, a thin coating layer is required. This requirement reduces the cross-sectional clearance area of the straight section flow channel formed by the mandrel and the die, leading to excessive pressure of the polymer melt at the shaping section, elevated die pressure, and backflow of the material melt, all of which directly impact the quality of the coating layer. To address these issues, this study conducted a non-isothermal numerical simulation of coating models both with and without a shaping section.

Robust finite-time consensus control for multi-agent systems with disturbances and unknown velocities.

In this paper, we investigated the finite-time consensus tracking problem for multi-agent systems with external bounded disturbances and input bounded disturbances and unknown velocities. Based on the Lyapunov finite-time theorem, a novel finite-time consensus control is constructed by using the backstepping method. For unknown velocities, the high-gain observer is used to estimate the velocity information.