Easily Fabricatable Shell Gripper for Packaging Multiple Cucumbers Simultaneously

A systematic trend analysis of 3D printing techniques used in specific soft robotic elements

Currently, many of the processing techniques for the location-based queries provide information of a single type of spatial objects, based on their spatial closeness to the query object. However, in real-life applications the user may be interested in obtaining information about different types of objects, in terms of their quality, cost, and neighboring relationship. We term the different types of objects with better quality and closer to each other the Neighboring skyline set (or NS set). Three new types of location-based queries, the Distance-based neighboring skyline query (Dist-NS query), the Cost-based neighboring skyline query (Cost-NS query), and the Budget-based neighboring skyline query (BGT-NS query), are presented to determine the NS sets according to user’s specific requirement. A R-tree-based index, the $$R^{a,c}$$-tree, is first designed to manage each type of objects with their locations, attributes, and costs. Then, a simultaneous traversal of the $$R^{a,c}$$-trees built on different types of objects is employed with several pruning criteria to prune the non-qualifying object sets as early as possible, so as to improve the query performance. Extensive experiments using the synthetic dataset demonstrate the efficiency and the effectiveness of the proposed algorithms.

Heterogeneous information networks have drawn much attention in recent years due to their significant applications, such as text mining, e-commerce, social networks, and bioinformatics. Clustering different types of objects simultaneously based upon not only their relations of the same type, but also the relations between different types of objects can improve the clustering quality mutually. In this paper, we propose a general model, in which both the homogeneous and heterogeneous relations are considered simultaneously, to describe the structure of the heterogeneous information networks and devise a novel parametric free multi-type overlapped clustering approach. In this model, different types of relations between different types of objects are represented by a group of matrices. In this way, we transfer the multi-type clustering problem into the information compression problem. Subsequently, greedy search approaches, which aim at describing the group of relational matrices with least bits, are proposed. Moreover, by discovering the discriminative clusters among different types of objects, we devise effective parameter-free strategies to discover either overlapping or non-overlapping structure among different types of clusters. Extensive experiments on real-world and synthetic data sets demonstrate our methods are effective and efficient.

Soft robots have advantages such as low weight and compact size compared to rigid robots. Variable stiffness is one of the key methods of improving the performance of a soft robot. The soft gripper grasps objects of various shapes or sizes based on the variable stiffness. In a previous study, we validated the variable stiffness mechanism where flexible and rigid segments were connected alternately in series. This paper presents a soft variable stiffness gripper that can be used to control the stiffness by pulling tendons. The soft gripper has three variable stiffness structures acting as fingers and the stiffness can be controlled using two motors by winding tendons. To understand the tendency of the stiffness variation and determine the design parameters, a compliant mechanism was developed using a pseudo-rigid-body model (PRBM). The experimental results show that the difference between the lowest and highest stiffness values of the fabricated variable stiffness gripper was 5.6 times the original. Similarly, the difference in the gripping weight was 19 times. Using the experimental results, the variable stiffness gripper can be designed and manufactured based on the required stiffness and used to grip various types of objects.

Inspired by nature's flexible and adaptable organisms, soft robotics are motorless robots made from highly compliant materials to work in confined environments and manipulate delicate objects. However, soft robots often suffer from early failure because of unexpected damage. At the same time, it is challenging to manufacture the geometrically complex structures of soft robots. This study introduces resins based on deep eutectic solvents (DES) to fabricate a pneumatically driven soft gripper using digital light processing (DLP). The resins consist of choline chloride (ChCl) as a hydrogen bond acceptor, glycerol (Gly), and acrylamide (AAm) as hydrogen bond donors. By utilizing the intense hydrogen bonding within DES, the resin can be rapidly cured by photopolymerization to form tough ionogels without chemical crosslinkers. The DES ionogels exhibit remarkable toughness and self‐healing performance compared to common hydrogels. Furthermore, the ionogels show not only efficient energy‐dissipating behavior but also achieve rapid self‐recovery. Finally, the DLP‐printed soft gripper from the DES‐based resin performs successful actuation and healing of macroscopic damages. This work presents a simple strategy to 3D print a soft robotic gripper with high toughness and self‐healing capability.

Biologically inspired or mimetic approaches have been traditionally widely adopted in robotic creative design. Generally, the most considered source for biorobotics and soft robotics are animals. Rarely, plants have been considered as a model of inspiration for innovative engineering solutions owing to their inconspicuous motion principles. In this work, a new type of plant-inspired soft robotic gripper was created by reconstructing and simulating the leaf structure and head formation mechanisms of cabbage. Firstly, according to the research reports of biological morphology and curling development mechanism of cabbage leaves, we determined that the flexible leaf with special hierarchical veins is the biological structure basis of curling formation. In the light of this observation, we designed a cabbage-inspired leaf bionic structure using paper substrate as a leaf body and using polylactic acid (PLA) polymer as leaf veins. This bionic design schema of cabbage leaves first has the advantage of ease of manufacture using 3D printing technology. In addition, due to the shape memory effect of PLA, we can control the reciprocal deformation of bionic leaves by controlling the temperature field. Undoubtedly, when two or more pieces of such bionic leaves are assembled together, they can be considered as a soft robotic gripper. Furthermore, we thoroughly studied the embodiment design of this bionic design concept as well as its 3D printing process. Finally, we built a prototype of this cabbage-inspired soft robotic gripper and successfully performed small objects (e.g., spitballs and cylinders) grasping experiments. Obviously, this research achievement first successfully integrated the bionic structure of plant deformation, direct digital manufacturing, and the control of shape memory materials. Secondly, this work realized the unified design of the structure, function, driving, and fabrication of robotics, and further expanded the family of the bionic robot, especially plant-like or plant-inspired robotic solutions.

This paper investigates the effects of encumbrance (holding different types of objects while using mobile devices) to understand the interaction difficulties that it causes. An experiment was conducted where participants performed a target acquisition task on a touchscreen mobile phone while carrying different types of bags and boxes. Mobility was also evaluated since people carry items from one place to another. Motion capture hardware was used to track hand and arm postures to examine how holding the different types of objects caused excessive movement and instability therefore resulting in performance to decline. The results showed encumbrance and mobility caused target accuracy to decrease although input while holding the box under the non-dominant arm was more accurate and exerted quicker targeting times than holding no objects. Encumbrance affected the dominant hand more than the non-dominant hand as targeting error significantly increased and caused greater hand instability. The issues caused by encumbrance suggest the topic requires more attention from researchers and users would benefit greatly if better interaction techniques and applications are developed to counteract the problems.

In an object oriented system, different types of objects may have one or more attributes in common. For example different types of objects in a library system might be loanable or catalogued. The first part of the paper introduces a distinction between object types and attribute types, showing that there are advantages in treating them as separate constructs of an object oriented programming language. Then generalized attribute types, (e.g. synchronized, journalized, protected) are discussed. It is shown how implementations involving a technique called bracket routines can lead to clearly modeled and cleanly implemented programs. It is then shown how the bracket technique can be effectively used to introduce protection and security concepts into a system. Among the clear advantages of this technique is that it results in better reusability of code.

There are various kinds of social media information, including different types of objects and relations among these objects, in music social communities such as Last.fm and Pandora. This information is valuable for music recommendation. However, there are two main challenges to exploit this rich social media information: (a) There are many different types of objects and relations in music social communities, which makes it difficult to develop a unified framework taking into account all objects and relations. (b) In these communities, some relations are much more sophisticated than pairwise relation, and thus cannot be simply modeled by a graph. We propose a novel music recommendation algorithm by using both multiple kinds of social media information and music acoustic-based content. Instead of graph, we use hypergraph to model the various objects and relations, and consider music recommendation as a ranking problem on this hypergraph. While an edge of an ordinary graph connects only two objects, a hyperedge represents a set of objects. In this way, hypergraph can be naturally used to model high-order relations.

The use of soft robots to interact with soft, fragile, and even living things has spurred interest in the development of soft robotic systems that can deform and adapt themselves to their environment through their inherent compliance. Current soft pneumatic actuator concepts require significant redesign to be repurposed from one function to another, and a complete soft robotic system may be composed of multiple types of actuators with varying materials, designs, and manufacturing methods. This complicates the process of designing and manufacturing soft robots that can tackle new tasks and environments. This work introduces a repeatable pattern of pouch motors with geometric constraints allowing the actuator to produce a programmable bending deformation. By varying the dimensions of the pattern, it is possible to produce different motions that can be used to build diverse robotic components, such as a soft robotic arm or a large soft robotic gripper.

This paper presents a study on improving the mechanical performance of soft pneumatic robots through parameterized layout and shape optimization of air chambers. Most soft robots are designed mainly by using biomimetics or engineering intuition. To fully explore the potential of the soft robots, however, it is highly desirable to develop a rational and systematic method to optimize the structural layout. In particular, structural stiffness of soft pneumatic robots is a key issue to be considered in practical design. This study first shows that the structural layout has a significant impact on the structural stiffness of the soft robot. In the optimization model, the design parameters explicitly defining the layout and shapes of the air chambers are to be optimized. In order to attain adequate structural stiffness so as to enhance the gripping force while improving the delivered motion, the output work is considered as the objective function to be maximized. This optimizaiton model enables a gradient-based mathematical programming algorithm to be used. It is shown through finite element analysis and physical experiments that the optimized layout and shape of the air chambers significantly improve the output work of the soft pneumatic gripper. The method is also adapted to be used in the structural design of a crawling soft robot.

On page 4449, D. Cohn, S. Magdassi, and co-workers describe a general and facile method based on 3D printing of methacrylated macromonomers to fabricate shape-memory objects that can be used in flexible and responsive electrical circuits. Such responsive objects can be used in the fabrication of soft robotics, minimal invasive medical devices, sensors, and wearable electronics. The use of 3D printing overcomes the poor processing characteristics of thermosets and enables complex geometries that are not easily accessible by other techniques.

Asymmetric bending enables rapid and efficient crawling motions in a soft robotic system. However, achieving asymmetric motion in soft robots with temperature‐responsive liquid crystal elastomers (LCEs) necessitates complex Joule heating configurations or precise temperature regulation. Herein, a simple electroless plating method is presented for patterning asymmetric temperature gradients on paper substrates, thereby facilitating the development of Joule heating, caterpillar‐inspired soft robots. Cellulose‐based paper substrates provide distinct advantages due to their porous structure, which enables facile electrode deposition via solution‐based processes and offers high mechanical deformability. Leveraging these material properties, Cu electrodes are asymmetrically deposited onto paper substrates by varying electrode widths. This variation induces differences in electrical resistance, generating significant temperature gradients across the substrate. Furthermore, it is demonstrated that temperature gradients could be modulated by adjusting the extent of Cu enhancement in the electrode patterns. it is fabricated energy‐efficient soft robots capable of directional crawling at a low actuation voltage of 0.5 V by integrating the paper substrate with LCEs in a bilayer architecture. The simplicity of the electrode patterning process, combined with the eco‐friendly nature of paper‐based actuators, presents a promising approach for the scalable and sustainable fabrication of soft robots with complex locomotion capabilities.

Tactile sensing is desirable for skillful object handling in soft robotics applications. Real-time measurement and identification of dynamic shear forces are crucial for slip detection and object interaction. This study proposes a soft sensor with a closed-loop feedback system for dynamic shear force detection to address object slippage in a soft robotic gripper. The sensor is made of a ferroelectric polymer with nanocarbon materials because of the resulting improved crystallinity and good sensitivity. The sensor shows high performance and high-speed response for detecting dynamic shear forces when fragile objects (e.g., vegetables) slip from the soft gripper. The artificial cutaneous sensor shows high sensitivity for grasping such objects with the gripper. Furthermore, the feedback system provides a control system for operations and avoids the need for training for various tasks, thus demonstrating the potential of the proposed system for novel soft robotics applications such as biomimetic electronic skin.

This work describes a new kind of soft gripper. Inspiration on nature is usual in Soft Robotics device creation. In this case, the inspiration came from a sea lamprey in order to create a closed structure soft robotic gripper. Usually the grippers have one or more soft actuators that act like fingers. Since it is difficult to know whether the fingers are really grasping an object, it is being proposed a closed structure to deal with this problem. While the proposed gripper involves the object as whole, a homogeneous force is applied on it. In addition to the details of the closed structure actuator manufacture description, two procedure tests are presented: an analysis of load versus pressure function and of the force versus pressure characteristics. At the end, some new research topics to the proposed soft gripper are discussed.