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This study delves into the analysis of roll bending machines, which are indispensable in the sheet metal forming industry. The primary goal is to investigate the diverse characteristics and versions of roll bending machines available in the market and to propose enhancements to boost their efficiency. Through an in-depth analysis of the current systems and an exploration of potential improvements, especially regarding the upper roll's transmission system, this research aims to optimize the operational performance of roll bending machines. Additionally, an internal functional analysis is conducted to provide a thorough understanding of the product and its mechanics, focusing on improving reliability, product quality, and costeffectiveness.

With the rapid development of profile processing industry, the processing shape, efficiency, and consistency of profiles are more and more demanding. In this case, the progress of bending machine tools was very important. In this study, the disadvantages and shortcomings of traditional three-roll bending machine are investigated, and a new design of three-roll bending machine is proposed, including a new mechanical structure, hydraulic pressure, and control system. ABAQUS was used to analyze the constrained mode of the table, and the first six order natural frequencies and natural vibration modes were obtained. A mathematical model was established to analyze the relationship between the pressure displacement and the forming radius under ideal working conditions, and the limit position of the downward movement of the lower press roll and the speed relationship between the lower press roll and the support roll are discussed. Based on the experimental data, the nonlinear curve fitting was carried out on the rebound compensation algorithm of asymmetric rolling bending forming. The fitting rebound compensation algorithm was carried out on the symmetric rolling bending forming experiment. The experimental results show that this algorithm can be applied to both symmetric rolling bending and asymmetric rolling bending.

Liu, X.; Hu, Y., and Xiao, C.-S., 2019. A new robust and fast iterative closest point algorithm for 3D Ship Hull Plate Bending Machines. In: Gong, D.; Zhu, H., and Liu, R. (eds.), Selected Topics in Coastal Research: Engineering, Industry, Economy, and Sustainable Development. Journal of Coastal Research, Special Issue No. 94, pp. 264–268. Coconut Creek (Florida), ISSN 0749-0208. The registration accuracy has a direct impact on the processing accuracy of sheet metal in 3D Ship Hull Plate Bending Machines. This study introduces a new distance measure, Root-Mean-Squared iterative closest point (RMS-ICP) algorithm to significantly improve the robustness of the algorithm, and reduce the influence of outliers. At the same time, the 3D point sets registration algorithm is optimized. In addition, the RMS-ICP has been optimized in robustness, registration accuracy and convergence speed in comparison with the original ICP and other improved ICP algorithms. The experiment results support that the performance of the RMS-ICP algorithm is better than other methods. Overall, the RMS-ICP algorithm is very effective in dealing with the point sets registration problem in 3D Ship Hull Plate Bending Machine.

In order to solve the current domestic sheet metal enterprise users has increased rapidly, but there are still most bending machine or manual operation problem, involving the employment difficult problems, according to labor shortage problem, must promote intelligent enterprise transformation, realize the exchange Labour \"machine\", the development and application of nc bending robot system is the inevitable developing trend of sheet metal industry, speed adaptive speed and oscillation is important in the development and application of nc bending robot system. This paper describes the system model of the speed adaptive speed and swing of the CNC bending robot system, and analyzes the performance of the speed adaptive speed and swing system comprehensively. The results of computer simulation show the consistency between simulation and theory.

The perovskite solar cell has emerged rapidly in the field of photovoltaics as it combines the merits of low cost, high efficiency, and excellent mechanical flexibility for versatile applications. However, there are significant concerns regarding its operational stability and mechanical robustness. Most of the previously reported approaches to address these concerns entail separate engineering of perovskite and charge-transporting layers. Herein we present a holistic design of perovskite and charge-transporting layers by synthesizing an interpenetrating perovskite/electron-transporting-layer interface. This interface is reaction-formed between a tin dioxide layer containing excess organic halide and a perovskite layer containing excess lead halide. Perovskite solar cells with such interfaces deliver efficiencies up to 22.2% and 20.1% for rigid and flexible versions, respectively. Long-term (1000 h) operational stability is demonstrated and the flexible devices show high endurance against mechanical-bending (2500 cycles) fatigue. Mechanistic insights into the relationship between the interpenetrating interface structure and performance enhancement are provided based on comprehensive, advanced, microscopic characterizations. This study highlights interface integrity as an important factor for designing efficient, operationally-stable, and mechanically-robust solar cells. Operational stability and mechanical robustness remain as engineering bottlenecks in perovskite solar cells technology. Here, Dong et al. introduce an interpenetrating perovskite at the electron-transporting-layer interface that enables a 1000-hour stable operation and high endurance against bending fatigue over 2500 cycles.

Human motions, such as joint/spinal bending or stretching, often contain information that is useful for orthopedic/neural disease diagnosis, rehabilitation, and prevention. Here, we show a badge-reel-like stretch sensing device with a grating-structured triboelectric nanogenerator exhibiting a stretching sensitivity of 8 V mm −1 , a minimum resolution of 0.6 mm, a low hysteresis, and a high durability (over 120 thousand cycles). Experimental and theoretical investigations are performed to define the key features of the device. Studies from human natural daily activities and exercise demonstrate the functionality of the sensor for real-time recording of knee/arm bending, neck/waist twisting, and so on. We also used the device in a spinal laboratory, monitoring human subjects’ spine motions, and validated the measurements using the commercial inclinometer and hunchback instrument. We anticipate that the lightweight, precise and durable stretch sensor applied to spinal monitoring could help mitigate the risk of long-term abnormal postural habits induced diseases. Human motions often contain information that is useful for orthopedic/neural disease diagnosis, rehabilitation, and prevention. Here, the authors show a badge-reel-like stretch sensing device with a grating-structured triboelectric nanogenerator for joints/spine bending or stretching sensing.

In bending process, the need of the precise material property characterization has become more and more important. So a new sheet metal bending equipment is independently developed to obtain the moment curvature characteristic in bending, bending-unloading and cyclic bending processes. The purpose of this paper is to describe the structure of the equipment and show the results about three kinds of bending tests for QP980. The tests performed by QP980 demonstrate that the bend and cyclic bend ability suits for researching non-linear springback and Bauschinger effect in this equipment.

Soft machines are a promising design paradigm for human-centric devices 1 , 2 and systems required to interact gently with their environment 3 , 4 . To enable soft machines to respond intelligently to their surroundings, compliant sensory feedback mechanisms are needed. Specifically, soft alternatives to strain gauges—with high resolution at low strain (less than 5 per cent)—could unlock promising new capabilities in soft systems. However, currently available sensing mechanisms typically possess either high strain sensitivity or high mechanical resilience, but not both. The scarcity of resilient and compliant ultra-sensitive sensing mechanisms has confined their operation to laboratory settings, inhibiting their widespread deployment. Here we present a versatile and compliant transduction mechanism for high-sensitivity strain detection with high mechanical resilience, based on strain-mediated contact in anisotropically resistive structures (SCARS). The mechanism relies upon changes in Ohmic contact between stiff, micro-structured, anisotropically conductive meanders encapsulated by stretchable films. The mechanism achieves high sensitivity, with gauge factors greater than 85,000, while being adaptable for use with high-strength conductors, thus producing sensors resilient to adverse loading conditions. The sensing mechanism also exhibits high linearity, as well as insensitivity to bending and twisting deformations—features that are important for soft device applications. To demonstrate the potential impact of our technology, we construct a sensor-integrated, lightweight, textile-based arm sleeve that can recognize gestures without encumbering the hand. We demonstrate predictive tracking and classification of discrete gestures and continuous hand motions via detection of small muscle movements in the arm. The sleeve demonstration shows the potential of the SCARS technology for the development of unobtrusive, wearable biomechanical feedback systems and human–computer interfaces. Strain gauges with both high sensitivity and high mechanical resilience, based on strain-mediated contact in anisotropically resistive structures, are demonstrated within a sensor-integrated, textile-based sleeve that can recognize human hand motions via muscle deformations.

Flexible electronics is a rapidly growing technology for a multitude of applications. Wearables and flexible displays are some application examples. Various technologies and processes are used to produce flexible electronics. An important aspect to be considered when developing these systems is their reliability, especially with regard to repeated bending. In this paper, the frequently used methods for investigating the bending reliability of flexible electronics are presented. This is done to provide an overview of the types of tests that can be performed to investigate the bending reliability. Furthermore, it is shown which devices are developed and optimized to gain more knowledge about the behavior of flexible systems under bending. Both static and dynamic bending test methods are presented.

The prolonged and continuous monitoring of mechanoacoustic heart signals is essential for the early diagnosis of cardiovascular diseases. These bodily acoustics have low intensity and low frequency, and measuring them continuously for long periods requires ultrasensitive, lightweight, gas-permeable mechanoacoustic sensors. Here, we present an all-nanofiber mechanoacoustic sensor, which exhibits a sensitivity as high as 10,050.6 mV Pa−1 in the lowfrequency region (<500 Hz). The high sensitivity is achieved by the use of durable and ultrathin (2.5 μm) nanofiber electrode layers enabling a large vibration of the sensor during the application of sound waves. The sensor is ultralightweight, and the overall weight is as small as 5 mg or less. The devices are mechanically robust against bending, and show no degradation in performance even after 1,000- cycle bending. Finally, we demonstrate a continuous long-term (10 h) measurement of heart signals with a signal-to-noise ratio as high as 40.9 decibels (dB).