Robotic tree climbers and strategies - a survey

As a result of the occupational migration, there is an acute shortage of trained laborers for performing tasks such as harvesting, pruning, pesticide spraying etc. Robotic tree climbers can solve the problem of shortage of laborers. Tree climbing robots belong to vertical climbing robots which moves against the gravitational pull of the earth. But the non-uniformity of tree trunk, inclination of tree irregularity and discontinuity, branches in chaotic arrangements etc. make it extremely challenging to develop a robot that climbs a tree and perform tasks. This review paper presents an introduction to the imperative for climbing robots and challenges in design of tree climbing robots. A study on existing tree climbing robots- climbing strategies, generic mechanical designs, requirements for autonomous climbers are also included. This survey found that there is a need of a novel robotic climber design which can offer better stability and faster operation with higher payload capability.