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Robotic automation is proving itself indispensable in the modern Chemistry laboratory, but adoption is slowed down by the technical challenges of implementing such systems. This paper reports on a novel adaptive gripper mechanism that can easily and reliably grasp cylindrical and prismatic objects of various sizes with limited clearance required. The proposed design exploits the inherent compliance of a cable that is driven to fully envelope the target object. The cable is run through a rigid finger, allowing the loop to be placed around objects with minimal clearance required and to provide support for the object once the grip is complete. Thanks to the compliant nature of the mechanism, the gripper requires minimal control effort to complete a gasping task. A prototype of the gripper has been designed and built for chemistry automation tasks, where it showed very high grasp reliability with ≤ 1 % grasp failures. [ABSTRACT FROM AUTHOR]

It is difficult to calculate the buckle cable force for the cantilever casting concrete arch bridge. Relying on the 180 m-span Jiming Sansheng Bridge, this paper put forward one method to calculate the initial buckle cable force based on the stress balance method. Firstly, the stress balance equation considering only tensile stress was derived for the first time, and the feasible region of the initial cable force was calculated by the allowable tensile stress of the arch rib, which improved the original stress balance method. Then, using the influence matrix, the initial buckle cable force was optimized by reducing the allowable tensile stress of concrete in stages, and finally the optimal initial cable force was obtained. The practical engineering results show that it is feasible to calculate the initial buckle force. The maximum tensile stress of concrete arch during the cantilever casting process is 1.52 MPa, meeting the specification requirements. The deviation between the calculated and measured stress is less than 12%. The calculated cable force agrees with the measured cable force, and the deviation is less than 2%. The initial cable force is only tensioned once, improving work efficiency. The method and experience of this paper can provide a reference for the arch bridge constructed by cantilever casting. [ABSTRACT FROM AUTHOR]

Fiber optic infrastructure is essential in the transmission of data of all kinds, both for the long haul and shorter distances in cities. Optical fibers are also preferred for data infrastructures inside buildings, especially in highly secured organizations and government facilities. This paper focuses on a reference measurement and analysis of optical fiber cables sensitivity to acoustic waves. Measurement was carried out in an anechoic chamber to ensure stable conditions of acoustic pressure in the range from 20 Hz to 20 kHz. The frequency response, the signal-to-noise ratio per frequency, and the Speech Transmission Index are evaluated for various types of optical fiber cables and different ceiling tiles, followed by their comparison. The influence of the means of fixing the cable is also studied. The results prove that optical fiber-based infrastructure in buildings can be exploited as a sensitive microphone. [ABSTRACT FROM AUTHOR]

The overhead-cable hybrid transmission lines are alternately connected by two types of lines, with a more complex structure and higher difficulty in fault location. This paper presents an ac-curate fault location method for overhead-cable hybrid lines based on traveling wave energy. Firstly, the basic concept of traveling wave energy is defined. Based on the attenuation charac-teristics of the traveling wave, the mapping relationship between traveling wave energy and fault location is analyzed. Secondly, considering the influence of S-transform error on the traveling wave energy propagation law, the traveling wave energy attenuation characteristics of common A-type and B-type hybrid lines are analyzed. Then, for the overhead-cable hybrid lines with different structures, the mapping relationship between the traveling wave energy at both ends of the line and the fault distance is quantitatively derived, and an accurate fault location method based on the initial traveling wave energy ratio at the same frequency at both ends of the line is proposed. Finally, a 110 kV hybrid transmission line fault simulation model is built in PSCAD/EMTDC, and the faults under different conditions are simulated in different line sections. The effectiveness and robustness of the proposed method are verified through the simulation. [ABSTRACT FROM AUTHOR]

By analysing the mechanical and geometrical relations between the main cable, tower, and splay saddles, and considering the coupling effect of the tower and splay saddles, an improved algorithm is proposed to determine the cable saddles pre-offsets of suspension bridges. The equilibrium relationship of the cable saddles, the compatible deformation condition, and the basic equation of the main cable shape are considered to establish several coupled non-linear equations up to 19, and the tower and splay saddle pre-offsets are obtained by solving the above equations with the Newton–Raphson method. This paper presents the initial value selection principle and the constraint conditions for solving the cable saddle pre-offsets of the plane cable suspension bridge and the calculation process ensures convergence. The calculation example demonstrates that the improved algorithm without an exact initial value can achieve excellent convergence. [ABSTRACT FROM AUTHOR]

The robotic manipulation of a heavy industrial cable is challenging to model and control because of the high number of degrees of freedom and the rigid-flexible coupling dynamics. In this paper, we report the development of modeling the cable effect and control methodology for robotic cable manipulation. Our cable effect model is based on the 2D convolutional neural network, which is a deep learning-based method uses the effective cable representation method to achieve the accurate, generalizable, and efficient estimation of the cable coupling forces and torques. Practical problems such as the measurement limits and time efficiency are considered in our method for real applications. With these approaches, we are the first to solve the problem of dynamic payload effect caused by heavy industrial cables in experimental cases. The used control methodology combines the active disturbance rejection control framework with the sliding mode control method, which can acquire promising tracking performance. We integrate our cable effect model into the control scheme, and demonstrate it satisfies the high-quality robotic manipulation of heavy cables. The performance of the proposed method is assessed with both a simulated system and real robot system. The results show that our method can estimate the cable coupling effect with over 85% accuracy and accomplish manipulation with a positioning error less than 0.01 mm. This reveals that our method is promising for robotic manipulation of heavy industrial cables and can accomplish the challenging cable insertion task. [ABSTRACT FROM AUTHOR]

Electrical cables, often referred to as 'blood vessels' and 'nerves' of the industry, play a vital role in the connection of electrical devices. However, traditional cables that lack distributed filtering functions are usually the primary coupling path for electromagnetic compatibility (EMC) problems. An innovative design for a filtering cable, which incorporates insulated electrical wires coated with a specific defected conductor layer (DCL), enables it to achieve distributed filtering advantages along its axis. Microwave network analysis is employed to build the two-port network model of filtering cable, which efficiently analyzes the cascading characteristics of periodic or aperiodic filtering cables. To validate, the flexible printed circuit board (FPCB) with sawtooth dumbbell-shaped DCL and mounted by capacitors is wrapped around the stripped section of the coaxial cable to manufacture a multi-stopband filtering cable. Simulated and measured results demonstrate that the proposed filtering cable can be effectively suppressed in the stopband, which can be adjusted by changing the values of capacitors. [ABSTRACT FROM AUTHOR]

In order to explore the performance evolution of prestressed anchor cables in corrosive environment, the corrosion immersion and corrosion damage performance tests of prestressed anchor bars in corrosive environment were carried out indoors. Based on the experimental results, the effects of stress level, pH and time on the corrosion process of prestressing anchor bars, the amount of corrosion per unit length and the change of mechanical properties were analyzed. It was found that the greater the stress level in the three corrosive media, the more severe the corrosion of the anchor bars, especially in acidic solutions; at the beginning of corrosion, prestressing anchor bars corrode fastest in neutral solution, followed by acidic and slowest in alkaline, with the continuation of corrosion, the degree of corrosion damage to anchor bars by acidic solution is more obvious; The corrosion damage of anchor tendons reflected by the corrosion amount per unit length is uniform corrosion, and local corrosion will aggravate the degree of corrosion damage of prestressing anchor tendons; The longer the corrosion time, the more serious the corrosion of anchor bars, and the 2 mechanical indexes of anchor bar elongation and fracture load have a significant decreasing trend. [ABSTRACT FROM AUTHOR]

The configuration of marine towing cable changes significantly during the turning process, with the rotating procedure with fixed cable length being the most frequent. To overcome these challenges, the configuration and dynamic properties of the marine towing cable must be addressed. However, under some particular operating situations, the tugboat must release the marine towed cable during rotation, resulting in a constant change in the length of the marine cable. In view of this, the towed cable is discretized into a lumped mass model based on the lumped mass method, and the dynamic analysis model of the rotation process of towed cable with variable length under different release speeds and different depths is established. This is done with reference to the specific parameters of a towed system, combined with the specific sea conditions of a particular sea area. Time-domain coupling analysis is used to determine the dynamic changes in configuration and stress of marine towing cable at various release speeds and depths. The results of the calculations have some guiding relevance for a certain engineering practice. [ABSTRACT FROM AUTHOR]

The rigid-flexible coupling cable system under large deformation is studied, and the beam element from absolute node coordinate formulation is used to establish flexible cable body of the system. Different numerical integral algorithms are discussed for solving the rigid-flexible cable system and an integration strategy which combines Implicit Euler with Minimum Residual Method (MINRES) is proposed. The influence of the position and number of rigid components and different the lengths of the flexible elements on the system dynamics are analyzed. With constant total mass of the system, higher number of rigid components and their uniform distribution contribute to stabilization of the swing of the flexible cable body. When the total length of the cable is constant, increasing the number of beam elements enhances the nonlinear characteristics of the swing motion and damages the stability. The influence of different factors on the movement of large deformation flexible cable body is obtained through modeling and simulation of the rigid-flexible coupling cable system. [ABSTRACT FROM AUTHOR]