Development of a Climbing-Robot for Spruce Pruning: Preliminary Design and First Results

Abstract

The aim of the project in which this work was conceived is the design of a climbing robot for pruning spruce trees without damaging the bark. According to the requirements and pruning methods for avoiding the flaws of the finished timber, guidelines and constraints for the mechatronic design of a new climbing robot for spruce-pruning activities were deduced. A 3-wheeled-driven system able to cope with the tree bark thanks to compression springs is chosen for the first functional design; a force-balance analysis is performed for understanding the climbing and equilibrium requirements also considering the additional weight of a pruning system installed on a cart moving on a guide placed on the robot main structure. The quasi-static model, the mechanical design and the related electronic and driver systems are here presented. The preliminary scaled mechatronic prototype is experimentally evaluated on poles with diameters in the range of the young spruces, i.e. 100–200 mm, in its main climbing features. These results will serve as basis for the further development of the system.