MATLAB-based Tools for Modelling and Control of Underactuated Mechanical Systems

Underactuated systems, defined as nonlinear mechanical systems with fewer control inputs than degrees of freedom, appear in a broad range of applications including robotics, aerospace, marine and locomotive systems. Studying the complex low-order nonlinear dynamics of appropriate benchmark underactuated systems often enables us to gain insight into the principles of modelling and control of advanced, higher-order underactuated systems. Such benchmarks include the Acrobot, Pendubot and the reaction (inertia) wheel pendulum. The aim of this paper is to introduce novel MATLAB-based tools which were developed to provide complex software support for modelling and control of these three benchmark systems. The presented tools include a Simulink block library, a set of demo simulation schemes and several innovative functions for mathematical and simulation model generation

INVERTED PENDULUM WITH LINEAR SYNCHRONOUS MOTOR SWING UP USING BOUNDARY VALUE PROBLEM

Research in the field of underactuated systems shows that control algorithms which take the natural dynamics of the system’s underactuated part into account are more energy-efficient than those utilizing fully-actuated systems. The purpose of this paper to apply the two-degrees-of-freedom (feedforward/feedback) control structure to design a swing-up manoeuver that involves tracking the desired trajectories so as to achieve and maintain the unstable equilibrium position of the pendulum on the cart system. The desired trajectories are obtained by solving the boundary value problem of the internal system dynamics, while the optimal state-feedback controller ensures that the desired trajectory is tracked with minimal deviations. The proposed algorithm is verified on the simulation model of the available laboratory model actuated by a linear synchronous motor, and the resulting program implementation is used to enhance the custom Simulink library Inverted Pendula Modeling and Control, developed by the authors of this paper

FRED—Flexible Framework for Frontend Electronics Control in ALICE Experiment at CERN

A substantial part of Distributed Control Systems are SCADA systems that require connection to low level electronics through standard industrial interfaces and protocols. When implementing Distributed Control Systems for physics experiments, it is often necessary to use custom made electronics that do not have the ability to communicate using standard protocols, but instead use custom communication protocols. This paper describes the new Front End Device (FRED) framework, which provides the possibility of connecting custom electronics to standard SCADA systems, thus filling the gap in the implementation of Distributed Control Systems that deploy custom electronics. The FRED framework also serves as a translation layer, which provides translation of raw values acquired from electronics to real physical quantities and vice versa. At the same time, it is easy to use, since there is no need for additional programming when used in the simple mode, and its entire functionality can be configured in several configuration files. In case of the need to perform more complex operations over electronics, it is possible to use the provided API for the implementation of additional program functionalities. Tests of the FRED framework have shown that it is fast and scalable enough for use within the Distributed Control Systems of large physics experiments. Based on experience with the implementation of the FRED framework in real-world systems of physics experiments, it can be stated that it meets all requirements for data processing throughput