Problem statement. Mobile robots are currently of significant interest among researchers and designers all over the world. One of the prospective drives of such robots is equipped by a pneumatically operated orthogonal system. The processes of development and improvement of orthogonal walking robots are significantly constrained because of the lack of an open-access comprehensive scientific and theoretical framework for calculating and designing of the energy-efficient and environmental-friendly pneumatic walking drives. Purpose. The main purpose of this research consists in the kinematic analysis, motion modelling and pneumatic system simulation of the mobile robot with an orthogonal walking drive. Methodology. The research is carried out using the basic laws and principles of mechanics, pneumatics and automation. The numerical modelling of the robot motion is conducted in MathCad software. The computer simulation of the robot kinematics is performed using SolidWorks software. The operational characteristics of the robot’s pneumatic system are investigated in Festo FluidSim software. Findings (results) and originality (novelty). The improved design of the mobile robot equipped by the orthogonal walking drive and turning mechanism is thoroughly investigated. The motion equations of the orthogonal walking drive are deduced, and the graphical dependencies describing the trajectories (paths) of the robot’s feet and body are constructed. The pneumatically operated system ensuring the robot rectilinear and curvilinear locomotion is substantiated. Practical value. The proposed design of the walking robot can be used while developing industrial (production) prototypes of mobile robotic systems intended for performing various activities in the environments that are not suitable for using electric power. Scopes of further investigations. While carrying out further investigations, it is expedient to design the devices for changing the robot locomotion speed and controlling the lifting height of its feet.
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