Science and Education Publishing Journal of Automation and Control 2372-3041 3 3 2015 12 15 Machines for In-Pipe Inspection 79 82 EN Alexander Gmiterko Ivan Virgala Lubica Miková Peter Frankovsky Tatiana Kelemenová Michal Kelemen Department of Mechatronics, Technical University of Kosice, Faculty of Mechanical Engineering, Kosice, Slovak Republic AUTOMATION2015338 10.12691/automation-3-3-8 2015 8 11 2015 10 9 2015 12 13 The paper deals with in-pipe machines based on directional friction and inertial stepping principle. Both type are developed for inner pipe with diameter 11 mm. The main purpose is inspection of inner pipe wall as prevention of cracks.