Developing a Robotic Lawn Mower for Climbing

Abstract

This Bachelor’s thesis presents the development of a prototype robotic lawn mower capable of climbing vertical obstacles such as curbs and small garden walls. Traditional robotic lawn mowers are limited by their inability to traverse such elevations, requiring manual repositioning. The project addressed this limitation by designing and integrating a height-adjustable wheel system allowing step-by-step elevation of the lawn mower’s body. Utilizing components from Husqvarna’s 450x and 550 EPOS models, a three-pair wheel configuration was developed where the middle and rear wheels can independently lift themselves and lower via a mechanical elevator system powered by motors. Emphasis was placed on maintaining stability during climbing through center of gravity management and the use of specialized middle wheels. Testing confirmed that the system functioned as intended and was effective in concept. However, manual assistance was occasionally required due to excessive friction in the elevators, which prevented the mower from completing the climbing process independently.