The article presents a three-dimensional linear model of the vestibulo-ocular reflex in darkness. The model is based on established relationships between the vestibular system and the extraocular muscles. The effectiveness of the model is evaluated through comparison with experimental observations. The model successfully reproduces realistic patterns of slow-phase vestibulo-ocular nystagmus during head rotations.

Capturing human movements and determining their features are often necessary in the development of devices worn by persons or used by them in daily work. In this regard, the problem of detecting the beginning of rotation seems to be relevant and has many applications in bionavigation and biomechanics. One of the main difficulties in these tasks is minimizing the delay in detecting the motion. In this paper the problem of detecting the head turn beginning by inertial sensors data fixed on it—three-axis accelerometer and CRS—is considered. The requirement to determine the head turn beginning appears when trying to solve the problem of supplementing vestibular information under special conditions, for example, to solve the problem of the vestibulo-sensory conflict that occurs in a state of weightlessness.

This article discusses a method for identifying the electrical conduction dynamic properties of voltage-gated ion channels. These channels are characterized by their multiple energy barriers, referred to as gate particles. The innovative method is developed using the Markov random processes theory, an approach that utilizes continuous time and and defined states. The number of states was taken to be equal to the number of energy barriers in the channel plus one. If random flows that switch the gate particles between an open and a closed state are Poisson processes, then a system of Kolmogorov linear differential equations for state probabilities is possible to use to mathematically describe the similar system channels. It is possible to find out the intensities of poisson event flows dependences on membrane potential for it fixed values, based on the model and voltage-clamp test results published in open access journals. Function parameters that describe the intensity of ion transitions through the channel in the Kolmogorov equation can be restored using the generalized least squares method. Examples of determining the transition intensities are described for two types of voltage-gated potassium channels, delayed rectifier potassium channels (IKdr, two identical activation gate particles) and channels with fast activation and inactivation processes (IKa, three identical activation and one inactivation gate particles). It is shown that channel activation and deactivation are described by solving the general Kolmogorov equation.

The article is devoted to the approach to the quantitative estimation of changes in the functional state of a person during an airplane flight based on the results of stabilometric and oculographic examinations of airplane passengers carried out before and after the flight. Fourteen volunteers of both sexes participated in the study. They performed 21 pairs of pre-flight and post-flight examinations. For the existing sample of volunteers, parameters were identified that had a consistent trend of change. These parameters include visual tracking quality and stabilometric characteristics. In 70 % probes a decrease in the slow phases of optokinetic nystagmus average speed was noted. In most volunteers, changes in the stabilometric parameters for the optokinetic test and the balance test on an unstable support in the form of foam plate are noticeable. The tracking speeds, the average velocity of the pressure center, and the quality index of the equilibrium function decreased after the flight in more than 70 % of all samples. It was noted that the Hurst index after the flight decreased compared to background sample, during get up on the polyurethane foam plate in the vast majority of volunteers. In test before the flight the change in this parameter was multidirectional. In a stabilometric test with a "stepped deviation", in which a volunteer on command made quick bends at a small angle due to a change in the angle in the ankle joint, 75 % of the subjects after the flights showed a decrease in the average speed.

Aim: the purpose of this paper was to compare motor responses to different hockey pucks in virtual reality in highly-and low-skilled ice hockey players.Materials and methods. A virtual environment was developed that simulates an ice hockey rink and 3 shots of different complexity (depending on the distance and speed of the puck). The study involved 12 male athletes (mean age = 21 years), including 7 ice hockey players, whose mean athletic experience was 14.25 years (ranks from 3rd junior to 1st adult). Motion analysis was performed with the SteamVR Tracking 2.0 system. Motor response was evaluated by a set of parameters, including maintaining the main stance, the motor response to the puck, the movements of the stick, and the response to warning signals. Motor activity was evaluated as the standard deviation of the change in angles in each of the joints (left and right knee, left and right hip, head).Results. The study showed that highly-and low-skilled ice hockey players differed significantly in the standard deviations of the change in angles in each of the joints and in the characteristics of the motor response to the puck.Conclusion. The results of the qualitative analysis allow us to conclude the following: highly-skilled ice hockey players, while maintaining a stance, have large amplitudes of vertical oscillations; highly-skilled ice hockey players maintain their stance while turning the shots aside; low-skilled athletes make more movements, often unnecessary. In fact, professional players are distinguished by significantly less physical activity and the absence of unnecessary movements that do not affect striking performance. Therefore, the higher the skill level of a hockey player, the more optimized will be the motor response to the puck.

The paper discusses the possibility of testing and correcting calibration of a portable acceleration recorder under orbital flight conditions. This recorder in-cludes a 3-axis accelerometer. The most difficult stage of calibration tests is the determination of its scale factors. The main difficulty of calibration is the lack of special equipment on the space station. It is proposed to use a standard mass meter installed on the ISS for testing accelerometers. The algorithms considered in the paper use data of the motion of the mass meter platform and the video camera records processing in addition to the recorder readings. For testing the algorithms under earth conditions, recordings were made that simulate conditions of an orbital flight. The proposed algorithms showed 2 % error in determining the scale factors of the accelerometers.

The study is devoted to analysis of records of rapid coordinated eye movements—saccades. Saccadic eye movements are performed by a human several thousand times a day and have a standard form. Changes in the movement of the eyes, including saccades, are noted in the case of disorders of the central nervous system, middle ear organs, and after a long space flight. Eye movement testing is used in medical practice for diagnosis and control when treating disorders in functioning of the organs of the inner ear, central nervous system, and strabismus. This paper proposes a method for approximating records of saccades with possible presence of pre- and postsaccadic movements. Numerical parameters describing preand postsaccadic movements and asymmetry of a saccade are suggested. The results of a statistical study of forms of saccades in a normal person are given. The statistical study has shown that the difference in forms of saccades is significant.

The paper presents the overview of technologies and technical facilities used to create simulations and simulators, including for the space industry, as well as technologies for tracking the human body and visual simulation. An example of the realization on the virtual reality headset together with the virtual reality suit is given. This hybrid technology will allow solving not only the tasks of training and practicing operations in various situations, but also the tasks of remote controlling of objects of different complexity.

This paper presents a model of saccadic eye movements. Eye movements are considered as being ballistic, since saccades (rapid concurrent movements of both eyes) occur several hundred thousand times per day; visual perception of the environment is interrupted by a saccade. The optimal control was constructed for the motion considered in three consecutively refined assumptions. The controls included in the time-optimal problem were the resultant moment of force exerted by the extraocular muscles, individual moments of force exerted by either muscle of the agonist–antagonist pair, and finally, the rate of change of these moments. This approach is consistent with the view that is currently upheld by physiologists, who believe that a saccade is programmed by the central nervous system before the beginning of an eye movement and is scarcely adjusted during the movement itself. The solution of the optimal control problem and the results obtained by subsequent numerical modeling of saccadic trajectories were compared with the published experimental data. The saccadic trajectories were compared based on the main sequence, the known consistent relationship between saccade amplitude and duration, which is the most widely applied and commonly accepted way of describing saccade data. The main sequence of saccades obtained from the solution of the optimal control problem formulated in the most complete form agreed well with published experimental results.

The problem of description and classification of rapid eye movements called saccades is considered. It is well known that the saccades are of various types. A classification of saccades is proposed according to the presence and types of pre-saccadic and post-saccadic movements. An algorithm is developed to determine the parameters that can be used to formally assign the saccade to one of the given types.

The components of force plate signals, generated by cardiac activity, are investigated. The person stays in an ortograde posture, sit in the relaxed pose and in a pose at which the trunk keeps vertically and don’t contact with seatback. On the basis of a spectral approach features of power plate “Stabilan” indications and hardware-software complex «A multifunctional chair» are analyzed at inspection of the person holding set postures in different functional conditions (before and after physical activity). It is shown that change of vertical force (ballistogramm data) is an integrative signal. Manifestation of muscular components in force plate signals for an ortograde posture and a human pose sitting with vertical trunk are discussed.