Abstract Minimally invasive surgery (MIS) is becoming one of the most important research areas in the field of medical robotics. The colonoscope is an example of a medical instrument that meets the needs of MIS. In this report, we present a new colonoscope tip, a system whose aim is to avoid perforation and haemorrhage of the colon wall which sometimes occur during medical procedures. It facilitates the surgeon's manoeuvrability, reducing operating time and increasing safety. This typical mechatronic system has been named EDORA (French acronym for Extrémité Distale à ORientation Automatique/distal tip with automated orientation). It is electropneumatically driven and comprised three metal bellows positioned 120° apart; three optical sensors placed on the upper plate of EDORA allow autonomous navigation of the colonoscope within the intestine. In this paper, we present the design of EDORA, describe geometrical and dynamical models, validate the models and present the results of travel through a curved tube.