Stabilization of unstable objects: coupled oscillators

Theoretical mechanics


Semenov M. E.1*, Solovyov A. M.1**, Popov M. A.2***

1. Voronezh State University, 1, Universitetskaya sq., Voronezh, 394006, Russia
2. Voronezh State University of Architecture and Civil Engineering, XX-letiya Oktyabrya St. 84, 394006 Voronezh, Russia



As is known, the problem of inverted pendulum plays a central role in the control theory. In particular, the problem of inverted pendulum (as a test model) provides many challenging problems to control design. Due to their nonlinear nature, pendulums have maintained their usefulness and now they are used to illustrate many ideas emerging in the field of nonlinear control. Typical examples are feedback stabilization, variable structure control, passivity-based control, back-stepping and forwarding, nonlinear observers, friction compensation, and nonlinear model reduction. The challenges of control made the inverted pendulum systems a classic tool in control laboratories. It should also be noted that the problem of such a system stabilization is a classical problem of the dynamics and control theory. Moreover, the model of inverted pendulum is widely used as a standard for testing of control algorithms, such as PID controller, neural networks, fuzzy control, etc.

The article investigates the dynamics of a mechanical system consisting of two inverted pendulums hinged on the moving platform and coupled by a spring. The force applied to the platform causing its horizontal motion is treated as a control. The purpose of this work consists in solving the problem of pendulums stabilization in vertical position using the horizontal motion of the platform at presence of the information on the angles of deviation. To solve this problem, we developed the algorithm of the pendulums stabilization near vertical position, found the stability zones and their dependence on the spring stiffness.


inverted pendulum, coupled oscillators, stabilization, control


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