The problem of improving the energy efficiency of the executive cyclic mechanisms of robotic systems is under consideration. Cyclic mechanisms with one degree of freedom, whose motion is described by the angular coordinate of the leading link are considered. The output link of mechanism is acted upon by a useful resistance force, which corresponds to the generalized force, depending on the position of the output link. The engine works with a constant angular velocity. It corresponds to the energetically optimal performance. Between the drive and the cycle mechanism, an additional mechanism-corrector with variable transmission Энергетическая эффективность цикловых механизмов робототехнических систем 71 ratio is installed, where one turn off the drive shaft corresponds to one turn of the driving link source mechanism. Friction in the system mechanisms is neglected. To improve the energy efficiency of cyclic mechanisms, we determine the conditions under which a mechanism-corrector, without changing the trajectory and during the movement of the executive body of the original mechanism, changes the law of its motion during the cycle and provides the optimum in terms of energy consumption, operation mechanism. Differential equations of motion of the considered mechanical system composed by the Lagrange equations with indefinite multipliers, and the equations of motion and parameters of a mechanism to ensure minimum loss of the engine are determined by solving an optimization problem in which optimizing functional is the energy dissipation in the engine. Euler equations are derived, involving additional isoperimetric conditions. The analysis shows a possible formulation of the problem of creating energy-saving cycle mechanisms. Structure and parameters of energy-saving mechanism are provided by the combination of three factors: the nature of the change of its kinetic energy within a cycle, change of the payload within the cycle and the nature of the motion of its leading executive links, and the fundamental law of the optimum mode of motion is written in the form of equality of the input to the mechanism of power and the power consumed to perform useful work and to overcome the forces of inertia. Evaluation of losses in the electric drive of walking robotic complex of «Vosminog-M» with propellers on the basis of cyclic mechanisms delineated in accordance with the relations obtained shows that the optimal mode provides a decrease of irreversible losses in induction motors of the robot by 15?20%.
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