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The purpose of this paper is to gain an in-depth understanding into the research progress, hot spots and future trends in smart gripping technology in the field of apparel smart manufacturing.

This work scrutinised the current research status of the five automatic grasping methods for garment fabrics including the pneumatic suction grasping, the electrostatic grasping, the intrusive grasping and the dexterous grasping. Specifically, the principles, characteristics, main devices and the impact on garment production were discussed.

In particular, soft finger of the dexterous grasping method has good flexibility and adaptability in the process of fabric grasping, which provides a new solution for garment production automation. Up to now, the reviewed method in general exhibit good grasping speed, high grasping stability and flat grasping process. However, in the face of complex fabric materials which are thin and flexible and do not return their original shapes when deformed in practical applications, the gripper for automatic fabric grasping need new technological breakthroughs in the positioning accuracy, grab efficiency and flexible grasping.

The outcomes offered an overview of the research status and future trends of the automatic grasping methods for garment fabrics in the field of apparel intelligent manufacturing. It could not only provide scholars with convenience in identifying research hot spots and building potential cooperation in the follow-up research but also assist beginners in searching core scholars and literature of great significance.

Soft grippers have safer and more adaptable human–machine and environment–machine interactions than rigid grippers. However, most soft grippers with single gripping postures have a limited gripping range. Therefore, this paper aims to design a soft gripper with variable gripping posture to enhance the gripping adaptability.

This paper proposes a novel soft gripper consisting of a conversion mechanism and four spring-reinforced soft pneumatic actuators (SSPAs) as soft fingers. By adjusting the conversion mechanism, four gripping postures can be achieved to grip objects of different shapes, sizes and weights. Furthermore, a quasi-static model is established to predict the bending deformation of the finger. Finally, the bending angle of the finger is measured to validate the accuracy of the quasi-static model. The gripping force and gripping adaptability are tested to explore the gripping performance of the gripper.

Through experiments, the results have shown that the quasi-static model can accurately predict the deformation of the finger; the gripper has the most significant gripping force under the parallel posture, and the gripping adaptability of the gripper is highly enhanced by converting the four gripping postures.

By increasing the gripping posture, a novel soft gripper with enhanced gripping adaptability is proposed to enlarge the gripping range of the soft gripper with a single posture. Furthermore, a quasi-static model is established to analyze the deformation of SSPA.

Varied shapes and sizes of different products with irregular rough surface and fragile properties give a challenge to traditional contact gripping. Single Bernoulli grippers are not suited to handle fragile objects as the impact of center negative pressure force could result in large deformation and stress which damage the materials, and they are also have some limitations for gripping objects with different large and small shapes. Thus, this paper aims to design a non-contact gripper for soft, rough-surfaced and fragile objects gripping with multi Bernoulli heads, which have optimal structures and parameters.

The compressed air is ejected into four Bernoulli heads through radial and long flow channels, then passes through four strip-shaped narrow gaps after fully developing in the annular cavity to provide negative pressure. Based on the mathematic model and the computational model, the key structural parameters affecting the gripping performance are selected, and parameters optimization of the gripper is performed by computational fluid dynamics simulation analysis and performance evaluation. The orthogonal method is used and L16 orthogonal array is selected for experimental design and optimization. The characteristics of the designed gripper are tested from the aspects of pressure distribution and lifting force.

From the applications in gripping different objects, the designed non-contact gripper can grip varied shapes and sizes of soft, rough-surfaced, fragile and sliced objects with little effect of torque.

In this paper, a non-contact gripper is designed for handling soft, rough-surfaced and fragile objects based on the Bernoulli principle. A systematic approach, which consists of modeling, simulation, optimization and measurement is provided for the non-contact gripper design and tests.

This paper proposes a classification scheme for the quantified analysis of micro‐grip principles. Micro‐part gripping has received quite some attention in micro‐assembly research. However, there is a lack of quantified data on the characteristics and applicability of micro‐grip principles. The micro‐grip principle is the physical principle that produces the necessary forces to get and maintain a part in a position with respect to the gripper. The classification scheme defines criteria that are essential in the evaluation and selection of a micro‐grip principle for gripping a given part. The criteria are defined on the basis of characteristics of the parts to be gripped, demands on the grip operation to be performed and characteristics of the environment in which the grip operation takes place. The classification scheme is evaluated using examples from literature.

The purpose of this paper is to design a microgripper that can achieve nondestructive gripping of a miniaturized ultra-thin-walled cylindrical part.

The microgripper is mainly made of an inflatable silica gel gasbag, which can minimize the damage to the part in the gripping process. This paper introduces the design principle of a flexible air-filled microgripper, which is applied in an in-house microassembly system with coaxial alignment function. Its parameters and performance specifications have been obtained by simulation, experiment demarcating. The results show that the microgripper is able to grasp an ultra-thin-walled part non-destructively.

For the microgripper, finite element simulations and experiments were carried out, and both results indicate that the microgripper can achieve nondestructive gripping of a miniaturized ultra-thin-walled cylindrical part, with good stability, great grasping force and high repeat positioning accuracy.

Gripping the ultra-thin-walled part may lead to deformation and destruction easily. It has been a big bottleneck hindering successful assembly. This article introduces a novel microgripper using an inflatable sac. The work is interesting from an industrial point of view for a specific category of assembly applications. It provides a theoretical guidance and technical support to design a microgripper for a miniaturized ultra-thin-walled part of different sizes.

The rope-climbing robot that can cling to a rope for locomotion has been a popular piece of equipment for some overhead applications due to its high flexibility. In view of problems left by existing rope-climbing robots, this paper aims to propose a new-style rope-climbing robot named Finger-wheeled mechanism robot (FWMR)-II to improve their performance.

FWMR-II adopts a modular and link-type mechanical structure. With the finger-wheeled mechanism (FWM) module, the robot can achieve smooth and quick locomotion and good capability of obstacle-crossing on the rope and with the link module based on a spatial parallel mechanism, the robot adaptability for rope environments is improved further. The kinematic models that can present configurations of the FWM module and link module of the robot are established and for typical states of the obstacle-crossing process, the geometric definitions and constraints that can present the robot position relative to the rope are established. The simulation is performed with the optimization calculating method to obtain the robot adaptability for rope environments and the experiment is also conducted with the developed prototype to verify the robot performance.

From the simulation results, the adaptability for rope environments of FWMR-II are obtained and the advantage of FWMR-II compared with FWMR-I is also proved. The experiment results give a further verification for the robot design and analysis work.

The robot proposed in this study can be used for inspection of power transmission lines, inspection and delivery in mine and some other overhead applications.

An ingenious modular link-type robot is proposed to improve existing rope-climbing robots and the method established in this study is worthy of reference for obstacle-crossing analysis of other rope-climbing robots.

The paper aims to present the design, validation and integration of a universal fabric gripper. Flexible material handling is one of the most challenging problems occurring in the field of manipulator robots. Because textile products shape and properties can widely vary, each textile and each technological operation should have its own specialized gripper. The objective of the work described here is therefore to design a universal gripper able to grip and transfer every kind of textile.

The design objectives are the ability to handle panels of varying shapes and sizes without material deformation and/or folding, and the easy integration with commercially available manipulator robots. To answer initial requirements and increase the textile gripping reliability, we opted to combine three different gripping technologies: vacuum, intrusion and pinch.

Each system was first validated independently through static tests. The vacuum technology offers a high reliability to handle impermeable materials. The intrusion technology is reliable for the manipulation of high porosity materials, while the pinch technology shows good results for all soft fabrics when combined with the vacuum technology. Then, the limits of the new gripper in terms of gripping capacity, compressed air consumption and characteristics and limitations of the flexible material handled were put in evidence using a robot arm. An automated selection program of the gripper based on the material characteristics has also been developed and implemented.

This paper fulfills an identified need to design a universal gripper able to grip and transfer every different kind of cut textile.

The purpose of this paper is to provide a technical review of a new Bernoulli gripper development using computed fluid dynamics (CFD) modeling, and also to outline an appropriate independent testing method for validating and evaluating process capability in terms of automated thin wafer handling. The investigation has been carried out by a collaborative way of Festo and Fraunhofer IPA as a connecting link between applied research and industrial needs.

Following an introduction, the paper first describes the basic development and fundamental principles of a gripper based on Bernoulli's law. The gripper was dimensioned and designed with the aid of CFD methods. The performance of the hardware was tested using extreme parameter settings while gripping thin, fragile workpieces. The performance of the gripper was tested from the aspects of shortest cycle times, positioning accuracy and air consumption and followed a manufacturer-independent design of experiments. A characterization of the gripping force generated during horizontal and vertical tension tests provides conclusive closed loop validation with regard to the gripper's air flow in the initial CFD model.

Photovoltaic (PV) grippers are challenging components since the handling objects, 200-120 μm thin crystalline silicon wafers with an area of 156×156 mm, are one of the most fragile parts as far as required handling speeds and cycle times are concerned.

The paper provides a detailed technical review of a CFD application used in the development of a Bernoulli gripper and also describes a method for testing and evaluating PV grippers for industrial scale applications. The article presents the results of a close cooperation regarding an industrial development (Festo AG & Co. KG) and independent applied research (Fraunhofer IPA) for advanced product benchmarking and validation in a relatively young but dynamic and increasingly-automated PV industry.

Flexible mechanical gripper has better safety and adaptability than a rigid mechanical hand. At present, there are few soft grippers for small objects on a millimeter scale. Therefore, the purpose of this paper is to design a soft pneumatic gripper for grasping millimeter-scale small and fragile objects such as jewelry and electronic components.

By simulating the clamping action of the bird’s mouth and combining the high flexibility of the soft material, the bird’s beak soft pneumatic gripper is designed. First, the internal cavity of the gripping end of the gripper is determined by bending deformation calculation, and the brief manufacturing process of the gripper is outlined. Then, the single finger of the soft gripper is modeled mechanically, and the relationship between air pressure and bending deformation of the single finger is obtained. Finally, the experimental platform of the soft mechanical gripper is built, and the gripping performance of silicone rubber material is tested by comparison test, bending deformation test, stability test, adaptability test and gripping accuracy test.

The designed gripper has the advantages of simple structure, convenient operation, easy grasping of different small objects of millimeter-scale and good adaptability. It can grasp the precise dispensing needle with a minimum diameter of 0.19 mm, and its accuracy meets daily use.

A new type of soft pneumatic, the mechanical gripper is proposed and manufactured. According to the shape of the bird’s beak and the calculation of bending performance, a hollow finger gripper with better bending performance is designed. Various test results show that the gripper has a significant clamping effect on millimeter small objects, which supplements the research field of millimeter small object gripper.

This paper describes guidelines for the design of grippers for use in modular manufacturing workcells. Gripper design is an important and often overlooked aspect of the design of a complete assembly system. Here, guidelines are presented which can be applied to a wide variety of grippers. Guidelines are divided into three major categories: those that improve system throughput, those that increase system reliability, and those that decrease cost. Designs of several grippers, currently being used in a modular manufacturing workcell, are presented as examples of the application of the guidelines to real world problems.