On Soft, Multi-Layer, Compact Kirigami Gripper Geometries Employing Compression and Extension Based Actuation Systems

Over the last decade a plethora of soft robotic devices has been proposed for the execution of complex grasping and dexterous manipulation tasks. Tasks that require such an increased dexterity are typically executed using fully-actuated, rigid end-effectors that are equipped with sophisticated sensing and are controlled with complex control laws. The new class of soft robotic devices offers an alternative to the traditional end-effectors and facilitates the development of robotic grasping and manipulation solutions that are lightweight, safe to interact with, affordable, and easy to use and control. Within the class of soft robotic grippers and hands, particular effort has been put into the development of ultra affordable, even disposable mechanisms based on origami and kirigami structures. In this paper, we propose a series of new kirigami gripper geometries for the implementation of soft, multi-layer, compact robotic grippers that can facilitate the execution of robust grasping tasks. In particular, we investigate how the shapes of the internal cuts of the kirigami geometries can facilitate the implementation of compression and extension based reconfiguration of the gripper structure and the efficient grasping of a plethora of objects employing a minimal, compact actuation systems. A series of reconfiguration characterisation, grasping, and force exertion experiments are conducted to better understand the working principles behind these new types of kirigami grippers and experimentally validate their efficiency in the execution of complex, everyday life grasping tasks.

Soft, Multi-Layer, Disposable, Kirigami Based Robotic Grippers:
On Handling of Delicate, Contaminated, and Everyday Objects

Grasping and manipulation are complex and demanding tasks, especially when they are executed in dynamic and unstructured environments. Typically, such tasks are executed by rigid articulated end-effectors, with a plethora of actuators that need sophisticated sensing and complex control laws to execute them efficiently. Soft robotics offers an alternative that allows for a simplified execution of these demanding tasks, enabling the creation of robust and efficient but also lightweight and affordable solutions that are easy to control and therefore operate. In this work, we present a new class of soft, multi-layer, disposable, kirigami-based robotic grippers that are fabricated employing simple 3D printed layers or laser cut PET films and silicone rubber using the concept of Hybrid Deposition Manufacturing (HDM). The proposed grippers can be actuated using a single actuator, they conform to the object shapes, and they facilitate the efficient handling of a variety of objects. Several designs have been designed and compared aiming to investigate the effect that the different kirigami cuts have in the grasping capabilities of each device. For this reason, a series of grasping and force exertion experiments have been performed to assess and compare the capabilities of the various developed devices. The results demonstrate that the proposed design and manufacturing methods can enable the creation of soft, kirigami-based grippers with superior grasping capabilities that can handle delicate, contaminated, and everyday life objects and can even be disposed if needed (e.g., after handling hazardous materials, such as medical waste).