A robotic device using gecko-inspired adhesives can grasp and manipulate large objects in microgravity

Abstract

Grasping and manipulating uncooperative objects in space is an emerging challenge for robotic systems. Many traditional robotic grasping techniques used on Earth are infeasible in space. Vacuum grippers require an atmosphere, sticky attachments fail in the harsh environment of space, and handlike opposed grippers are not suited for large, smooth space debris. We present a robotic gripper that can gently grasp, manipulate, and release both flat and curved uncooperative objects as large as a meter in diameter while in microgravity. This is enabled by (i) space-qualified gecko-inspired dry adhesives that are selectively turned on and off by the application of shear forces, (ii) a load-sharing system that scales small patches of these adhesives to large areas, and (iii) a nonlinear passive wrist that is stiff during manipulation yet compliant when overloaded. We also introduce and experimentally verify a model for determining the force and moment limits of such an adhesive system. Tests in microgravity show that robotic grippers based on dry adhesion are a viable option for eliminating space debris in low Earth orbit and for enhancing missions in space.

Effect of Hydrogen Concentration on the Growth of Carbon Nanotube Arrays for Gecko-Inspired Adhesive Applications

“…This unique adhesive capability of geckos has led to the development of advanced adhesives, including dry adhesives, which unlike chemical adhesives, leave no residue [3]. Such dry adhesives generally have micro-nano array structures, and are expected to be suitable for robotic end-effectors [4][5][6][7]. At present, there are generally two main types of materials being researched as materials for gecko-inspired dry adhesives [8]: Synthetic polymers [5,9,10] and vertically-aligned carbon nanotubes (VACNTs) [11][12][13][14].…”

Soft wall-climbing robots

“…Achieving the ability to climb walls with agile motions has long been a challenge in the field of robotics (1)(2)(3). Although a number of rigid wallclimbing robots have been developed with good performances in applications such as inspection, surveillance, and cleaning (4-28), they generally rely on complicated mechanisms composed of rigid actuators (such as electromagnetic or electrostatic motors) and transmission components (such as pulleys, wheels, or belts).…”

Effective Capture of Nongraspable Objects for Space Robots Using Geometric Cage Pairs

“…Most space debris comes from abandoned rocket bodies, defunct satellites, their exploded fragments, space rocks, and out-of-control spacecraft, which are typically called non-cooperative objects [2]. The development of space robotic technologies for dealing with non-cooperative objects has attracted substantial interest [3].…”

“…For dealing with this class of objects, two main strategies are employed: One is to use flexible capturing theories and methods, including tether nets [18], [19], tether grippers [20], [21], robotic capsules [22] and robotic tentacles [23]; the other is to capture objects using robotic arms with customized capture effectors, of which end-effectors are the most important tools as they can directly determine the success of tasks [24]. An innovative strategy is proposed for adhering directly to the surfaces of objects and an electro-adhesive gripper [17] and a gecko-inspired adhesive gripper [3] are d e v el o pe d f o r ca p t u ri n g n o n -g ra sp a bl e o b je cts. [22] is proposed for capturing asteroids.…”