The cyclic modular approach is proposed for mechatronic object design. The approach is based on a new conceptual model of the object and a new algorithm of its design. The model consists of invariant and changeable parts. The parts have a hierarchical structure. The proposed algorithm allows for creating the object from the basis principle to the construction step by step. It makes it possible to design an adequate object in all forms of its representations: structure, schematic diagram, mathematical model and construction. Each of these forms has an invariant part, i.e. the structure of the functioning process of the object. Application of the proposed approach reduces the time needed for the object design.

In this work, a novel perspective is proposed to develop schematics solutions for electro-hydraulic positioning actuators. The basis of the design approach has been established, which includes: a set of possible desired properties of actuators; a series of defined typical positioning methods; variants of schematic structures; a quantitative assessment method for specific properties based on influencing factors; the quantitative relationship between the structure and properties of actuators, as well as the method for overall evaluation of the actuator's performance based on the total score. The results obtained can serve as the basis for an effective design approach, which allows for reducing the number of iteration cycles while developing new electro-hydraulic positioning actuator schematic solutions.