Design and operational peculiarities of four-degree-of-freedom double-legged robot with pneumatic drive and turning mechanism

Abstract

Problem statement. Mobile robots are of significant interest among scientists and designers during the last several decades. One of the prospective drives of such robots is based on pneumatically operated walking (stepping) system with no use of electric, heat, magnetic or other types of energy. This allows the use of pneumatically-driven robots in the cases when the use of other energy sources is prohibited (e.g., in some gaseous or fluid mediums). At the same time, the walking (stepping) type of moving increases the manoeuvrability and cross-country capability of the mobile robot, and decreases the harmful effect of its interaction with the supporting surface (e.g., the fertile soil surface) in comparison with wheeled or caterpillar drives. Purpose. The main purpose of this research consists in substantiation of structure and parameters of pneumatic system of four-degree-of-freedom mobile robot with orthogonal walking drive and turning mechanism. Methodology. The research is carried out using the basic laws and principles of mechanics, pneumatics and automation. The numerical experiment is conducted in MathCAD software; the computer simulation of the robot’s motion is performed using SolidWorks software; the modelling of the pneumatic system operation is carried out in Festo FluidSim Pneumatic software. Findings (results) and originality (novelty). The improved structure of the mobile robot with orthogonal walking drive and turning mechanism is proposed. The pneumatically operated system ensuring the robot’s curvilinear motion is substantiated. Practical value. The proposed design of walking robot can be used while designing industrial (production) prototypes of mobile robotic systems for performing various activities in the environments that are not suitable for using electric power or other types of energy sources. Scopes of further investigations. While carrying out further investigations, it is necessary to design the devices for changing motion speed of the robot and the height of lifting of its feet.

Modelling and simulation of pneumatic system operation of mobile robot

“…In [10], there was performed the structural and kinematic analysis of the pantograph-type manipulator with three degrees of freedom used for conducting the prescribed technological operations. The paper [11] was dedicated to improvement of the design parameters of the pneumatically-driven orthogonal robot able to perform rectilinear locomotion (Fig. 1).…”

“…1) and operational peculiarities of the four-degree-of-freedom doublelegged robot with pneumatic drive and turning mechanism are thoroughly analyzed in [11]. In particular, the previous authors' paper [11] presents the improved design of the pneumatically-driven orthogonal walking robot equipped with turning mechanism, analyses its rectilinear and curvilinear locomotion, considers the corresponding timing diagrams of operation of the pneumatic cylinders under the conditions of rectilinear and curvilinear motion. The present paper continues the investigations initiated in [11].…”

“…In particular, the previous authors' paper [11] presents the improved design of the pneumatically-driven orthogonal walking robot equipped with turning mechanism, analyses its rectilinear and curvilinear locomotion, considers the corresponding timing diagrams of operation of the pneumatic cylinders under the conditions of rectilinear and curvilinear motion. The present paper continues the investigations initiated in [11]. 12 -pneumatic cylinder fixator; 13 -turning platform; 14 -cylindrical hinge; 16 -guide fixator…”

“…The pneumatic circuit describing the control system of operation of the robot's pneumatic cylinders during its curvilinear motion has been developed in [11] (Fig. 2 a).…”