Soft, Multi-Layer, Disposable, Kirigami Based Robotic Grippers: On Handling of Delicate, Contaminated, and Everyday Objects Joao Buzzatto, Mojtaba Shahmohammadi, Junbang Liang, Felipe Sanches, Saori Matsunaga, Rintaro Haraguchi, Toshisada Mariyama, Bruce MacDonald, and Minas Liarokapis Abstract— Grasping and manipulation are complex and demanding tasks, especially when 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 simplified execution of these demanding tasks, enabling the creation of robust, efficient, lightweight, and affordable solutions that are easy to control and operate. In this work, we introduce a new class of soft, kirigami-based robotic grippers, we study their post-contact behavior, and we investigate different cut patterns for their development. We follow an experimental approach in which several designs are proposed and employed in a series of grasping and force exertion tests to compare their capabilities and post-contact behavior. The results of such experiments indicate a clear relationship between degree of reconfiguration and grasping force, and provide key insights into the effect of the cut patterns in the performance of the designs. These findings are then used in the design process of an improved version of multi-layer, disposable kirigami grippers that are fabricated employing simple 3D printed layers and silicone rubber using the concept of Hybrid Deposition Manufacturing (HDM). A series of experimental 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 off in an automated way (e.g., after handling hazardous materials, such as medical waste). I. I NTRODUCTION Currently, soft grippers are being used in many real-life grasping tasks, making interaction with both users and ob- jects safer, simpler, and more reliable. Soft devices conform better to the object’s shape than rigid grippers, offering robustness and delicate interactions. This is an important feature when dealing with delicate and fragile objects like fruits, raw eggs, food packages, etc. Joao Buzzatto, Mojtaba Shahmohammadi, Junbang Liang, Felipe Sanches, and Minas Liarokapis are with the New Dexterity research group, Department of Mechanical and Mechatronics Engineering, The University of Auckland, New Zealand. E- mails: {jsan819,msha851,jlia904,fsan668}@aucklanduni.ac.nz, minas.liarokapis@auckland.ac.nz Bruce MacDonald is with the Centre for Automation and Robotic Engineering Science, Department of Electrical, Computer and Soft- ware Engineering, The University of Auckland, New Zealand. E-mail: b.macdonald@auckland.ac.nz Saori Matsunaga, and Toshisada Mariyama are with the Information Technology R&D Center, Mitsubishi Electric Corporation, Japan. Emails: matsunaga.saori@dc.mitsubishielectric.co.jp, mariyama.toshisada@ab.mitsubishielectric.co.jp. Rintaro Haraguchi is with the Advanced Technology R&D Center, Mitsubishi Electric Corporation, Japan. Email: Haraguchi.Rintaro@dc.mitsubishielectric.co.jp. Fig. 1. One of the proposed soft, multi-layered, disposable kirigami- based robotic grippers developed using a 3D printed layer and silicone rubber using the concept of Hybrid Deposition Manufacturing (HDM). The gripper is equipped with sockets that can accommodate different fingertips to improve grasping performance. The connections of the actuation points with the 3D printed core module are reinforced using Dyneema strings routed in a loop along the edges of the kirigami gripper to prevent the silicone strips from stretching and breaking. Subfigure a) shows the gripper with fingertips designed to pick up thin objects, like a credit card. Subfigure b) shows an annotated view of the kirigami-based gripper laying down flat. The anchoring sheet is a 3D printed PLA sheet with distributed holes for better adhesion to the silicon. It serves mostly as an anchor for the PLA fingertips connectors and Dyneema tendon routing, which is a single 3D printed piece. This gripper design is derived based on the results from the experimental investigation presented in this work. It demonstrates how the insights from the analysis can be used to develop more effective kirigami- inspired grippers. There are many different approaches to making soft grippers. One of the most common types is pneumatic soft grippers, in which the gripper is actuated by inflating and deflating a soft structure such as a silicone medium reinforced by fiber [1]–[3]. It is also possible to use dielectric materials to make soft grippers [4]–[6]. In this method, actuation occurs by the polarization of conductive materials, which are separated by a soft material such as an elastomer. These grippers have a relatively high force to mass ratio [7]. The other type of soft gripper which has proven to be