A climbing robot based on Hot Melt Adhesion

Abstract

Robust climbing in unstructured environment has been one of the long-standing challenges in robotics research. Among others, the control of large adhesion forces is still an important problem that significantly restricts the locomotion performance of climbing robots. The main contribution of this paper is to propose a novel approach to autonomous robot climbing which makes use of Hot Melt Adhesion (HMA). The HMA material is known as a very economical solution to achieve large adhesion forces, and the forces can be varied by controlling its material temperature. For locomotion in both inclined and vertical walls, this paper investigates the basic characteristics of HMA material, and proposes a design and control of climbing robot that uses the HMA material for attaching and detaching its body to the environment. The robot is equipped with servomotors and thermal control units to actively vary the temperature of the material, and the coordination of these components enables the robot to walk against the gravitational forces even with a relatively large body weight. A real-world platform is used to demonstrate locomotion on a vertical wall, and the experimental result explains feasibility and overall performances of this approach.

DESIGN & DEVELOPMENT OF ROPE CLIMBING DEVICE FOR MULTI-STOREY BUILDINGS : A REVIEW

“…Osswald [7] proposed using hot melt adhesive (HMA) to reach robotic mountaineering locomotion by means of this process. For this, motor is used as basic drive function.…”

Climbing vertical terrains with a self-contained robot

“…Thermal bonding requires a climbing robot to attach itself onto a surface with heated HMAs. HMAs may come from an onboard supplier [14], [15], or may be preloaded and kept on a robot's feet [16]. A bonding area can be formed between the robot and the surface during cooling, which can be either passive (as in [15] and this paper), or active with Peltier elements or fans [14], [16].…”

“…The former way requires longer time for heating up, but a small motor force would be enough for detachment [14]. The latter way can save the heating time, but it requires a relatively large motor force [16] or a torsion [15].…”

“…Recently, a novel climbing technology was developed using unconventional material hot melt adhesives (HMAs) [14], [15], [16]. The main advantage is the high attachment strength resulting from thermal bonding (10 4 -10 6 Pa depending on the type of HMA and material of surfaces [15], [16]): Theoretically, only an area of 4 cm 2 HMA is needed for a robot to hold a combination of its own mass and payload up to 60 kg on a vertical surface [14] (subject to mechanical strength of the robot).…”

“…The main advantage is the high attachment strength resulting from thermal bonding (10 4 -10 6 Pa depending on the type of HMA and material of surfaces [15], [16]): Theoretically, only an area of 4 cm 2 HMA is needed for a robot to hold a combination of its own mass and payload up to 60 kg on a vertical surface [14] (subject to mechanical strength of the robot). Furthermore, HMAs can be applied to almost any solid surface, and successful multi-step climbing has been demonstrated on vertical flat surfaces of wood [14] and metal [16]. However, due to the presence of thermal processes, all previous robots were powered by external energy sources, but the energy cost of this method has not been measured.…”