Improving the designing of marine tethered systems using the principles of shipbuilding 4.0

This paper considers the issues and theoretical aspects related to improving the design of maritime tethered systems (MTSs) with flexible links (FLs) using underwater towed systems (UTSs) as an example. That allows them to be used in the early stages of design by implementing the principles of Shipbuilding 4.0 and BIM technologies. Such regimes have not previously been described by existing mathematical models (MMs). The expected result of the current study is a significant decrease in the cost of different resources. At the same time, the basic reliable results of design solutions could be obtained already in the early stages of design. The theoretical basis of the proposed method for improving the design of MTS with FL is the improved design concept (IDC) for MTS with FL while the tool base of the method is a special modeling complex (SMC). The use of IDC along with SMC at the research (pre-prototype) design phase reduces the number of MTS design stages. The proposed method to improve the design of MTS with FL, based on the MM that notates the dynamics of MTS FL and MTS with FL, makes it possible to investigate different modes of operation of almost all MTS classes. That allows devising the recommendations for predicting possible operational loads in order to design their elements. At the same time, there is an opportunity to improve the existing methods for calculating and designing MTS with FL with the required properties and parameters, and to bring them to the level of engineering application. The application of SMC at the pre-prototype design stage makes it possible to avoid the use of physical modeling of the operational regimes of MTS with FL associated with the full-scale testing on the high seas

Hamiltonian formulation and energy-based control for space tethered system deployment and retrieval

Usually, the dynamic equations of tethered systems are derived using Lagrangian formulation. However, Hamiltonian formulation is also widely used for mechanical systems because of its well-known symplectic structure property. In this paper, the dynamic equations of the tethered system are deduced using Hamiltonian formulation. The goodness of the Hamiltonian formulation is intuitive to reveal the energy balance property that corresponds to the passive property. Furthermore, the Hamiltonian function of the tethered system is employed to facilitate the design of the controller. The energy-based control is to achieve the tether deployment/retrieval with suppressing the tether liberation. Numerical simulations are used to demonstrate the effectiveness of the designed controller.

EEG Radiotelemetry in Small Laboratory Rodents: A Powerful State-of-the Art Approach in Neuropsychiatric, Neurodegenerative, and Epilepsy Research

EEG radiotelemetry plays an important role in the neurological characterization of transgenic mouse models of neuropsychiatric and neurodegenerative diseases as well as epilepsies providing valuable insights into underlying pathophysiological mechanisms and thereby facilitating the development of new translational approaches. We elaborate on the major advantages of nonrestraining EEG radiotelemetry in contrast to restraining procedures such as tethered systems or jacket systems containing recorders. Whereas a main disadvantage of the latter is their unphysiological, restraining character, telemetric EEG recording overcomes these disadvantages. It allows precise and highly sensitive measurement under various physiological and pathophysiological conditions. Here we present a detailed description of a straightforward successful, quick, and efficient technique for intraperitoneal as well as subcutaneous pouch implantation of a standard radiofrequency transmitter in mice and rats. We further present computerized 3D-stereotaxic placement of both epidural and deep intracerebral electrodes. Preoperative preparation of mice and rats, suitable anaesthesia, and postoperative treatment and pain management are described in detail. A special focus is on fields of application, technical and experimental pitfalls, and technical connections of commercially available radiotelemetry systems with other electrophysiological setups.