Models and algorithms for the formation of commanding influences of the control system of the rehabilitation exoskeleton two-link foot

The purpose of research is to develop a mathematical model of a two-link active foot of a rehabilitation exoskeleton for the lower extremities and to obtain data for generating the setting effects on the device drives.

Methods. The article discusses a method for creating reference actions for the drive control system of a two-link foot of a rehabilitation exoskeleton. This device is designed for complex mechanical processing of the ankle joint in order to restore its mobility and bring movements closer to a natural gait. For this purpose, the video trajectory capture method is used in the framework of the experiment, which creates trajectories of movement of characteristic points of the foot taking into account the gait parameters and anthropometry of the patient. When processing the data, a 5th-order Fourier series is used, which allows approximating the obtained experimental trajectories with a given accuracy and ensuring their smoothness.

Results. The work established that the mathematical model of a two-link foot allows analyzing and predicting the movement of the robot's foot in various rehabilitation modes. The model takes into account control and disturbance effects, as well as parameters such as mass, moment of inertia, step length, leg lift height, and other characteristics. The results of mathematical modeling allow synthesizing the robot's drive system - a set of mechanisms that transmit movement from the engine to the foot links. This will help ensure reliable and efficient operation of the device. In addition, the modeling results will be used to design the main structural elements of the robot, such as hinges, fasteners, shock absorbers, etc.

Conclusion. The results of mathematical modeling allow us to calculate the robot's drive system - a set of mechanisms that transmit movement from the engine to the foot links. This will help ensure reliable and efficient operation of the device. In addition, the modeling results will be used to design the main structural elements of the robot, such as hinges, fasteners, shock absorbers, etc. This will allow us to create a durable and long-lasting device that can perform its functions in various operating conditions.

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