Investigation of robust ship course control based on auxiliary loop method

A novel robust control law is investigated on the problem of ship stabilization on the trajectory, which allows one to compensate perturbations in the parameters of the mathematical model of ship dynamics in cases of their changes caused by external conditions, namely: sea waves, currents, wind gusts, etc. To implement the proposed control law, only measured adjustable values are required such as the yaw angle and the control action that is the angle of the rudder of the ship. The synthesized ship course control system was investigated in MATLAB. The law of controlling the ship’s course with unknown parameters and external disturbances in the power supply is proposed. The design of the control law is based on a robust auxiliary loop algorithm and Khalil observers. The simulations illustrate the efficiency of the proposed control law.

Optical Pulling Using Chiral Metalens as a Photonic Probe

Optical pulling forces, which can pull objects in the source direction, have emerged as an intensively explored field in recent years. Conventionally, optical pulling forces exerted on objects can be achieved by tailoring the properties of an electromagnetic field, the surrounding environment, or the particles themselves. Recently, the idea of applying conventional lenses or prisms as photonic probes has been proposed to realize an optical pulling force. However, their sizes are far beyond the scope of optical manipulation. Here, we design a chiral metalens as the photonic probe to generate a robust optical pulling force. The induced pulling force exerted on the metalens, characterized by a broadband spectrum over 0.6 μm (from 1.517 to 2.117 μm) bandwidth, reached a maximum value of −83.76 pN/W. Moreover, under the illumination of incident light with different circular polarization states, the longitudinal optical force acting on the metalens showed a circular dichroism response. This means that the longitudinal optical force can be flexibly tuned from a pulling force to a pushing force by controlling the polarization of the incident light. This work could pave the way for a new advanced optical manipulation technique, with potential applications ranging from contactless wafer-scale fabrication to cell assembly and even course control for spacecraft.

Walking strides direct rapid and flexible recruitment of visual circuits for course control in

Flexible mapping between activity in sensory systems and movement parameters is a hallmark of successful motor control. This flexibility depends on continuous comparison of short-term postural dynamics and the longer-term goals of an animal, thereby necessitating neural mechanisms that can operate across multiple timescales. To understand how such body-brain interactions emerge to control movement across timescales, we performed whole-cell patch recordings from visual neurons involved in course control in Drosophila. We demonstrate that the activity of leg mechanosensory cells, propagating via specific ascending neurons, is critical to provide a clock signal to the visual circuit for stride-by-stride steering adjustments and, at longer timescales, information on speed-associated motor context to flexibly recruit visual circuits for course control. Thus, our data reveal a stride-based mechanism for the control of high-performance walking operating at multiple timescales. We propose that this mechanism functions as a general basis for adaptive control of locomotion.

Aerial course stabilization is impaired in motion-blind flies

Visual motion detection is among the best understood neuronal computations. As extensively investigated in tethered flies, visual motion signals are assumed to be crucial to detect and counteract involuntary course deviations. During free flight, however, course changes are also signalled by other sensory systems. Therefore, it is yet unclear to what extent motion vision contributes to course control. To address this question, we genetically rendered flies motion-blind by blocking their primary motion-sensitive neurons and quantified their free-flight performance. We found that such flies have difficulties maintaining a straight flight trajectory, much like unimpaired flies in the dark. By unilateral wing clipping, we generated an asymmetry in propulsive force and tested the ability of flies to compensate for this perturbation. While wild-type flies showed a remarkable level of compensation, motion-blind animals exhibited pronounced circling behaviour. Our results therefore directly confirm that motion vision is necessary to fly straight under realistic conditions.

Vessel heading control systems with switchable regulators

The purpose of this work is to study the possibilities of improving the quality of the processes of controlling the movement of the vessel along the course by combining individual standard controllers. Of the known scientific directions devoted to the problem being solved, the closest is the theory of systems with variable structure, in which, due to switching, a unique useful property is achieved, which are not possessed by individual switched structures. The article is devoted to the approach to the construction of the ship course control system, which is based on the principle of switching regulators during the transient process. This makes it possible to improve the quality of control processes in the system by using the features of individual regulators, in particular, the application of the switching principle made it possible to significantly increase the speed of the system in comparison with systems without switching and ensure the desired monotonic nature of the control process. The proposed approach is illustrated based on switchable P-controllers. The results of modeling the developed ship course control system are presented and discussed.

MODERNIZATION OF HIGHER PHARMACEUTICAL EDUCATION IN THE CONDITIONS OF REFORMING CONTROL AND SUPERVISION ACTIVITIES

The training of skilled workers for efficient liaison with regulatory authorities who are capable of training pharmaceutical companies for inspections is one of the most pressing problems in the field of circulation of medicines. The research has identified significant gaps and lack of fundamental knowledge by the senior executives, quality representatives, key personnel and pharmaceutical sales representatives on issues of liaison with regulatory authorities in the context of drastic reformation of administrative procedures. The research presents proprietary experience of teaching a new optional elective course "control and supervision of pharmaceutical activities" at the chair of pharmacy of North-Ossetian State Medical Academy, and characteristic of the training package of the new optional discipline for fifth year students and specialists of pharmaceutical organizations. The research analyses several approaches to solving the tasks of improving basic skills required to prepare for tests for students and specialists in the context of contemporary demands of the pharmaceutical labor market.