The problem of stability of the plane motion of mobile robots, including those with walking propulsion devices, is considered. Two modes of propulsion devices are compared: "pushing" and "pulling". The solution of two model problems on the plane motion of a solid body caused by kinematic and force action is presented.

The problem of increasing the traction and dynamic properties of mobile robots with walking propulsion devices is considered. The interdependence of the traction forces developed by the propulsion devices and the forces of resistance to the movement of robots, due to their interaction with the environment, is analyzed. A mathematical model is proposed based on the quasi-static nature of the robot’s movement and taking into account the static uncertainty of the problem. Static indeterminacy is due to the presence of propulsion devices on each of the sides and interacting with the supporting surface in the amount of more than two. A feature of the solution is also taking into account the gait and schedule of the robot’s movement, which characterize the time sequence of the propulsion devices being in the phase of interaction with the supporting surface and in the phase of transfer to a new position. The gait is also characterized by the mode coefficient, which is the ratio of the time the propulsion device is in the stance phase to the total time of the cycle of its movement. An optimality criterion is introduced on the basis of which the design perfection of the propulsion devices and the place of their installation on the robot is evaluated. The optimality criterion consists of two indicators: the value of the maximum traction force and the average force of resistance to movement. The tractive force is assumed to be proportional to the sum of the maximum normal loads acting on each propulsion device unit, and the resistance force to the squares of the same loads. Simulation modeling has been carried out, proving the dependence of the magnitude of traction properties and the forces of resistance to movement on the location of the propulsion devices. Two systems of vertical arrangement of the points of suspension of propulsion devices were compared. It has been established that a sufficiently small change in the vertical coordinate of the suspension point of even one propulsion devices has a noticeable change in the maximum traction forces and movement resistance forces. It is concluded that by adjusting the vertical position of the propulsion devices foot relative to the robot body, it is possible to control the traction properties and movement resistance, as well as the importance of the positioning accuracy of the foot of the propulsion devices walking mechanism during movement.

Mobile robots with walking propulsion devices operating in a "pulling" mode, which, as a rule, are unstable, are considered. It is explained to the jamming of propulsion device due to the orthogonality of the acting force to the virtual displacement of the point of application. The task is to develop such an algorithm for controlling the robot, which consists in purposefully changing the geometric orientation of the propulsion devices controlled by the swing drive, which will ensure stable motion. A method for controlling the orientation of the walking plane with its initial deviation from the programmed position is proposed, based on the implementation of a discrete control algorithm, which provides for the introduction of such a piecewise constant function at each step of the mover, which has received an initial perturbation, which will provide a stable motion mode in a finite number of steps. The change in the orientation of the walking planes of the propellers connected with the steering is controlled, and thereby the direction of movement of the robot body changes in the first step, as in the subsequent ones. The described algorithm assumes the fulfillment of two necessary conditions: the presence of an information-measuring system that controls the orientation of the walking planes and ensuring that the interaction forces of the feet controlled by the steering of the propulsion devices with the supporting surface are sufficient for the absence of slippage. An algorithm for controlling "dependent" propulsion devices (working out the programmed translational motion of the body) is presented, taking into account the fact that their orientation depends on the orientation of the controlled ones, which consists in changing the step length, which should also be determined to ensure movement stability. The main task of controlling "dependent" propulsion devices, which do not change the orientation of their walking plane at the initial moment of time, is to determine the points for setting the feet by changing the step length, in accordance with the established criteria and design constraints, in particular, energy efficiency, maximum efforts in drives, maximum and minimum stride length. The propulsion device will start to work in a stable "pushing" mode at the final stage of motion correction, by performing a sequence of actions. It has been established that the "pulling" mode of the walking propulsion device can be stable, with appropriate control.

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This article deals with the problem of well shut-in underwater emergency hydrocarbon. A well shut-in method using controlled anchor-rope driver moving a plug pontoon with a small positive buoyancy is proposed. A possible sequence of operations for well shut-in is drawn up.