Simulation and optimization of giant radial tire vulcanization process

AbstractThe process of curing a pneumatic tire as one of the most important working procedures, directly identify the quality of tire, because the physical and mechanical properties of rubber in the state of overcure or undercure are significantly decreased. The finite element analysis (FEA) method was introduced to evaluate the tire's state of cure (SOC) in this paper, and the optimization of cure conditions of giant radial tire was also referred to ensure that tire constituents achieved the proper SOC and improved the quality of tire. Results indicated that when the cure time was cut down 35 minutes by optimization process, most part of tire compound is appropriate cured. So that the energy cost was remarkable cut down and the productivity was rising in evidence

Recent Progress in Flexible Pressure Sensor Arrays

Flexible pressure sensors that can maintain their pressure sensing ability with arbitrary deformation play an essential role in a wide range of applications, such as aerospace, prosthetics, robotics, healthcare, human–machine interfaces, and electronic skin. Flexible pressure sensors with diverse conversion principles and structural designs have been extensively studied. At present, with the development of 5G and the Internet of Things, there is a huge demand for flexible pressure sensor arrays with high resolution and sensitivity. Herein, we present a brief description of the present flexible pressure sensor arrays with different transduction mechanisms from design to fabrication. Next, we discuss the latest progress of flexible pressure sensor arrays for applications in human–machine interfaces, healthcare, and aerospace. These arrays can monitor the spatial pressure and map the trajectory with high resolution and rapid response beyond human perception. Finally, the outlook of the future and the existing problems of pressure sensor arrays are presented

Effect of Geometric Error on Friction Behavior of Cylinder Seals

The tribological characteristics of the cylinder directly affect the operation accuracy of the pneumatic servo system. However, the geometric error has a significant effect on its tribological behavior and the related research is insufficient. Thus, the dynamic friction process of rubber seals has been investigated considering the influence of geometric errors. Firstly, based on the self-made friction test platform, the friction force of the rubber seals was studied and the influence law of geometric error on the contact area of the rubber seal ring was revealed. Secondly, the numerical model of the friction and contact of the rubber seals for the cylinder segment was developed by using the finite element simulation method and the influence laws of machining errors, such as roundness and straightness on the friction characteristics, were revealed. Finally, synergy effects of roundness and straightness in the friction behavior of rubber seals considering geometric errors was investigated, which lays a foundation for the accurate prediction of cylinder dynamic mechanical properties

Experiment and Simulation Research on the Fatigue Wear of Aircraft Tire Tread Rubber

The road surface and the tread pattern structures directly affect the wear performance of aircraft tire, especially for lateral sliding conditions. In this paper, wear tests of tread block with different draft angles and root radiuses, different interfaces, and different slip angles were carried out, and combined with the simulation, the effects of tread groove structure and slip angle on the wear mechanism were analyzed. Results indicated that the influences of draft angle were greater than the root radius; the wear geometry of the tread block decreased when the draft angle increased in the range of 0° to 15°, but for the root radius, the wear geometry of each sample was similar to a strip shape. A considerable material loss occurred at the front edge when the slip angle increased, and the slip angle was larger in the range of 0° to 45°. Combined with the simulation and wear test, fatigue wear and abrasive wear of the slide surface are dominant factors when considering the effects of tread groove structure and slip angle, and both front edges of the tread blocks roll up repeatedly; the coefficient decreases with the increase in load when the cement concrete pavement interface is dry, but for a wet interface, the coefficient decreases softly

Design and Analysis of Porous Elastomeric Polymer Based on Electro-Mechanical Coupling Characteristics for Flexible Pressure Sensor

Elastomeric polymers have gained significant attention in the field of flexible electronics. The investigation of the electro-mechanical response relationship between polymer structure and flexible electronics is in increasing demand. This study investigated the factors that affect the performance of flexible capacitive pressure sensors using the finite element method (FEM). The sensor employed a porous elastomeric polymer as the dielectric layer. The results indicate that the sensor’s performance was influenced by both the structural and material characteristics of the porous elastomeric polymer. In terms of structural characteristics, porosity was the primary factor influencing the performance of sensors. At a porosity of 76%, the sensitivity was 42 times higher than at a porosity of 1%. In terms of material properties, Young’s modulus played a crucial role in influencing the performance of the sensors. In particular, the influence on the sensor became more pronounced when Young’s modulus was less than 1 MPa. Furthermore, porous polydimethylsiloxane (PDMS) with porosities of 34%, 47%, 67%, and 72% was fabricated as the dielectric layer for the sensor using the thermal expansion microsphere method, followed by sensing capability testing. The results indicate that the sensor’s sensitivity was noticeably influenced within the high porosity range, aligning with the trend observed in the simulation

Bioinspired Spinosum Capacitive Pressure Sensor Based on CNT/PDMS Nanocomposites for Broad Range and High Sensitivity

Flexible pressure sensors have garnered much attention recently owing to their prospective applications in fields such as structural health monitoring. Capacitive pressure sensors have been extensively researched due to their exceptional features, such as a simple structure, strong repeatability, minimal loss and temperature independence. Inspired by the skin epidermis, we report a high-sensitivity flexible capacitive pressure sensor with a broad detection range comprising a bioinspired spinosum dielectric layer. Using an abrasive paper template, the bioinspired spinosum was fabricated using carbon nanotube/polydimethylsiloxane (CNT/PDMS) composites. It was observed that nanocomposites comprising 1 wt% CNTs had excellent sensing properties. These capacitive pressure sensors allowed them to function at a wider pressure range (~500 kPa) while maintaining sensitivity (0.25 kPa−1) in the range of 0–50 kPa, a quick response time of approximately 20 ms and a high stability even after 10,000 loading–unloading cycles. Finally, a capacitive pressure sensor array was created to detect the deformation of tires, which provides a fresh approach to achieving intelligent tires