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Online estimation of the state of health (SOH) of lithium-ion batteries (LIB) is crucial for the security and stability operation of battery management systems. In order to overcome the problem such as long training time, large amount of computation, and complex debugging process of the LIB SOH estimation methods based on traditional data-driven, an LIB SOH estimation method based on fusion health factor (HF) and integrated extreme learning machine is proposed. The interval data with a high correlation with the SOH was found by analyzing the dQ/dV and dT/dV curves of the battery. Multi-dimensional HFs are extracted from the interval data, and the indirect HF are obtained by principal component analysis. The stochastic learning algorithm of extreme learning machine is used to establish the nonlinear mapping relationship between indirect HF and SOH. Considering the unstable output of a single model, an integrated extreme learning machine model is proposed. The unreliable output is eliminated by setting credibility evaluation rules for the estimation results, and the estimation accuracy of the model is improved. Finally, the method proposed in this paper is validated using the NASA LIB aging dataset and the LIB aging dataset of Oxford University. The results show that the average absolute percentage error of SOH estimation method proposed is less than 1%, and it has a high accuracy and reliability.

The fracture behavior of ultra-high performance concrete (UHPC) with different depths of notches and curing ages were investigated using a three-point bending test. The ratio of total fracture energy to initial fracture energy raises from 5.9 to 8.3, and then drops to 7.8 with the increases of depth of notch. The fracture energy of UHPC beams with different depths of notches has size effect based on comprehensive analysis. Furthermore, the ratio of total fracture energy to initial fracture energy diminishes from 17.9 to 8.2. The two types of fracture energy of UHPC grow rapidly as the curing age increases, and the influence of curing ages on the fracture energy is mainly reflected in the energy growth within 14 days. In addition, a more suitable improved softening curve model for UHPC is proposed based on the above experimental results and analysis of fracture process. The model could not only better predict the peak load in the rising section of the crack mouth open displacement (CMOD) curve, but also simulate the failure process in the descending section curve.

Tendon–sheath structures are commonly utilized to drive surgical robots due to their compact size, flexibility, and straightforward controllability. However, long-distance cable tension estimation poses a significant challenge due to its frictional characteristics affected by complicated factors. This paper proposes a miniature tension sensor array for an endoscopic cable-driven parallel robot, aiming to integrate sensors into the distal end of long and flexible surgical instruments to sense cable tension and alleviate friction between the tendon and sheath. The sensor array, mounted at the distal end of the robot, boasts the advantages of a small size (16 mm outer diameter) and reduced frictional impact. A force compensation strategy was presented and verified on a platform with a single cable and subsequently implemented on the robot. The robot demonstrated good performance in a series of palpation tests, exhibiting a 0.173 N average error in force estimation and a 0.213 N root-mean-square error. In blind tests, all ten participants were able to differentiate between silicone pads with varying hardness through force feedback provided by a haptic device. [ABSTRACT FROM AUTHOR]

Magnetic anchor and guidance system has been widely used in laparoendoscopic single-site surgery with the benefit of small wound, wide field of vision (FoV), and convenience for repeated positioning. This paper introduces a novel three DoF laparoscopic surgical robot (LSR) based on double-leg ultrasonic motor (DUM) which features small dimension, fast response, and high positional precision. Piezoelectric ceramic (PZT) plates can excite longitudinal and bending coupled vibration of DUM and the two phase in-plane three order bending vibration can form traveling wave to drive DUM rotor. DUM stator is optimized by non-dominated sorting genetic algorithm-II for good consistency of two working mode frequencies and negligible influence of adjacent interference modes on working modes, which improves motion stability and driving efficiency. The mechanical characteristic of DUM under different chamfer parameters has been studied through comparative experiments and the design of robot prototype is completed further. For clockwise and counterclockwise rotation, the maximum no-load rotary speeds are 333.75 and 335.77 rpm, and the maximum output torques are 2 and 1.6 N mm. The experimental platform for FoV measurement is built to verify that LSR can adjust the posture to obtain suitable surgical FoV, indicating that the application of DUM in LSR has significant advantages and great potential. [ABSTRACT FROM AUTHOR]

Membrane separation has been acknowledged as an advanced technology to handle the oil spills. However, most of the superhydrophilic/underwater superhydrophobic membranes currently applied for oil/water separation would lose their superwettability when exposed to salty marine environments, leading to serious membrane plugging and separation performance deterioration. Herein, inspired by seawater fish and mussels, a simple, green, and versatile one-step co-deposition strategy is proposed for fabricating a ternary zwitterionic coating with strong surface hydration on diverse membranes, showing excellent anti-fouling properties in high salinity environments, even in the saturated NaCl solution. Moreover, the modified membrane performs well in the long term when separating surfactant-stabilized oil-in-seawater emulsion and with impressive recyclability. The ternary zwitterionic coating membrane exhibits great potential in treating oily wastewater in marine. A ternary zwitterionic coating membrane was prepared by a straightforward and universal one-step co-deposition strategy for efficient long-term emulsion separation in high salinity marine environment. [Display omitted] • A one-step co-deposition strategy for preparing superhydrophilic zwitterionic coating. • Featured outstanding excellent salt-resistance capability and anti-fouling property. • Achievement of efficient separation of oil/seawater mixture and oil-in-water emulsions. • Promotion of long-term oil-in-seawater emulsion separation with 98 % recovery. [ABSTRACT FROM AUTHOR]