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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.

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.

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.

The purpose of this paper is the increase the flexibility of robots used for handling of 3D (food) objects handling by the development and evaluation of a novel 3D Bernoulli gripper.

A new gripper technology have been designed and evaluated. A deformable surface have been used to enable individual product handling. The lift force generated and the force exerted on the product during gripping is measured using a material tester instrument. Various products are tested with the gripper. A experimental/theoretical approach is used to explain the results.

A deformable surface can be used to generate a lift force using the Bernoulli principle on 3D objects. Using a small forming a significant increase in the lift force generated is recorded. Increasing the forming further was shown to have little or even negative effects. The forces exerted on the product during forming was measured to be sufficiently low to avoid product damage.

To be able to improve the grippers lift strength a better model and understanding of the flow is needed.

A novel Bernoulli gripper for 3D Bernoulli gripping have been designed and evaluated. The gripper enables flexible and delicate handling of various product shapes, 3D as well as 2D. Increased utilization of robots in the food industry can be gained.

The Bernoulli gripper fixedly installed on the manipulator is subject to limitations such as a small-working region and poor anti-interference capacity. This paper aims to propose a novel Bernoulli gripper design that involves the connection of a positive stiffness component such as a spring in series, based on the force characteristic curve synthesis method, to optimize the mechanical performance.

The proposed gripper is designed and manufactured. In the suction procedure, the force characteristic curve of the proposed gripper is theoretically and experimentally investigated. In the hovering detection procedure, a dynamic model of the manipulator-gripper-workpiece system is established, and an apparatus is set up to compare the displacements of the workpiece and the manipulator. The proposed gripper is finally applied in the lifting procedure, showing good impact resistance.

The optimization of mechanical performance of the proposed gripper is realized. The proposed gripper has the effect of increasing the stiffness of the negative stiffness part of the force characteristic curve and reducing the stiffness of the positive stiffness part, increasing the working region. The stability and the anti-interference ability of the workpiece under high-frequency vibration are improved. Meanwhile, the impact resistance in the lifting procedure is enhanced, compared with the original one.

This research proposes a novel design for the Bernoulli grippers to optimize the mechanical performance. The proposed gripper has advantages of a larger working region, better anti-interference ability and better impact resistance. These findings serve as important theoretical and experimental references for the design of the Bernoulli gripper.

Vortex grippers use tangential nozzles to form vortex flow and are able to grip a workpiece without any physical contact, thus avoiding any unintentional workpiece damage. This study aims to use experimental and theoretical methods to investigate the effects of nozzle diameter on the performance.

First, various suction force-distance curves were developed to analyze the effects of nozzle diameter on the maximum suction force. This study determines the tangential velocity distribution on the workpiece surface by substituting the experimental pressure distribution data into simplified Navier-Stokes equations and then used these equations to analyze the effects on the flow field. Subsequent theoretical analysis of the distribution of pressure and circumferential velocity further validated the experimental results. Next, by rearranging these relationships, the study considered the effects of nozzle diameter on the inherent vortex gripper characteristics. In addition, this study developed various suction force-energy consumption curves to analyze the effects of nozzle diameter.

The results of this study indicated that the vortex gripper’s circumferential velocity and maximum suction force decrease with increasing nozzle diameter. Nozzle diameter did not significantly affect the inherent frequency of the vortex gripper-workpiece inertial system or the corresponding suspension stability of the workpiece. However, an increase in nozzle diameter did effectively increase the vortex gripper’s suspension region. Finally, as the nozzle diameter increased, the energy required to achieve the same maximum suction force decreased.

This study’s findings can enable optimization of nozzle design in emerging vortex gripper designs and facilitate informed selection among existing vortex grippers.

The purpose of this paper is to propose a casting process for the production of double-chamber soft fingers, which avoids the problems of air leakage and fracture caused by multistep casting. This proposed method facilitates the simultaneous casting of the inflation chamber and the jamming chamber.

An integrated molding technology based on the lost wax casting method is proposed for the manufacture of double-chamber soft fingers. The solid wax core is assembled with the mold, and then liquid silicone rubber is injected into it. After cooling and solidification, the mold is stripped off and heated in boiling water, so that the solid wax core melts and precipitates, and the integrated soft finger is obtained.

The performance and fatigue tests of the soft fingers produced by the proposed method have been carried out. The results show that the manufacturing method can significantly improve the fatigue resistance and stability of the soft fingers, while also avoiding the problems such as air leakage and cracking.

The improvement of the previous multistep casting method of soft fingers is proposed, and the integrated molding manufacturing method is proposed to avoid the problems caused by secondary bonding.

In multi-robot cooperation, the cloud can share sensor data, which can help robots better perceive the environment. For cloud robotics, robot grasping is an important ability that must be mastered. Usually, the information source of grasping mainly comes from visual sensors. However, due to the uncertainty of the working environment, the information acquisition of the vision sensor may encounter the situation of being blocked by unknown objects. This paper aims to propose a solution to the problem in robot grasping when the vision sensor information is blocked by sharing the information of multi-vision sensors in the cloud.

First, the random sampling consensus algorithm and principal component analysis (PCA) algorithms are used to detect the desktop range. Then, the minimum bounding rectangle of the occlusion area is obtained by the PCA algorithm. The candidate camera view range is obtained by plane segmentation. Then the candidate camera view range is combined with the manipulator workspace to obtain the camera posture and drive the arm to take pictures of the desktop occlusion area. Finally, the Gaussian mixture model (GMM) is used to approximate the shape of the object projection and for every single Gaussian model, the grabbing rectangle is generated and evaluated to get the most suitable one.

In this paper, a variety of cloud robotic being blocked are tested. Experimental results show that the proposed algorithm can capture the image of the occluded desktop and grab the objects in the occluded area successfully.

In the existing work, there are few research studies on using active multi-sensor to solve the occlusion problem. This paper presents a new solution to the occlusion problem. The proposed method can be applied to the multi-cloud robotics working environment through cloud sharing, which helps the robot to perceive the environment better. In addition, this paper proposes a method to obtain the object-grabbing rectangle based on GMM shape approximation of point cloud projection. Experiments show that the proposed methods can work well.

A non‐contact end‐effector was applied to lift three different materials which have different physical properties. These materials are mica (as rigid material), carton (as semi‐rigid material) and non‐rigid material (woven fabric). This end‐effector operates on the principle of generating a high‐speed air flow between nozzles and the specimen surface thereby creating a vacuum which levitates the materials with no mechanical contact. In this paper, the handling results of these materials are compared with each other. The changes in the physical behavior of lifting materials were observed during the experimental work. The effect of the various air flow rates on the non‐contact handling clearance gap between the nozzle and the materials were also investigated. As a result, it was observed that the non‐contact end‐effector could be applied to handle different flat materials.