Magnetically responsive soft materials are soft composites where magnetic fillers are embedded into soft polymeric matrices. These active materials have attracted extensive research and industrial ...interest due to their ability to realize fast and programmable shape changes through remote and untethered control under the application of magnetic fields. They would have many high-impact potential applications in soft robotics/devices, metamaterials, and biomedical devices. With a broad range of functional magnetic fillers, polymeric matrices, and advanced fabrication techniques, the material properties can be programmed for integrated functions, including programmable shape morphing, dynamic shape deformation-based locomotion, object manipulation and assembly, remote heat generation, as well as reconfigurable electronics. In this review, an overview of state-of-the-art developments and future perspectives in the multifunctional magnetically responsive soft materials is presented.
Soft robot review Lee, Chiwon; Kim, Myungjoon; Kim, Yoon Jae ...
International Journal of Control, Automation, and Systems,
02/2017, Letnik:
15, Številka:
1
Journal Article, Book Review
Soft robots are often inspired from biological systems which consist of soft materials or are actuated by electrically activated materials. There are several advantages of soft robots compared to the ...conventional robots; safe human-machine interaction, adaptability to wearable devices, simple gripping system, and so on. Due to the unique features and advantages, soft robots have a considerable range of applications. This article reviews state-of-the-art researches on soft robots and application areas. Actuation systems for soft robots can be categorized and analyzed into three types: variable length tendon, fluidic actuation, and electro-active polymer (EAP). The deformable property of soft robots restricts the use of many conventional rigid sensors such as encoders, strain gauges, or inertial measurement units. Thus, contactless approaches for sensing and/or sensors with low modulus are preferable for soft robots. Sensors include low modulus (< 1 MPa) elastomers with liquid-phase material filled channels and are appropriate for proprioception which is determined by the degree of curvature. In control perspective, novel control idea should be developed because the conventional control techniques may be inadequate to handle soft robots. Several innovative techniques and diverse materials & fabrication methods are described in this review article. In addition, a wide range of soft robots are characterized and analyzed based on the following sub-categories; actuation, sensing, structure, control and electronics, materials, fabrication and system, and applications.
This work presents a soft hand capable of robustly grasping and identifying objects based on internal state measurements along with a combined system which autonomously performs grasps. A highly ...compliant soft hand allows for intrinsic robustness to grasping uncertainties; the addition of internal sensing allows the configuration of the hand and object to be detected. The finger module includes resistive force sensors on the fingertips for contact detection and resistive bend sensors for measuring the curvature profile of the finger. The curvature sensors can be used to estimate the contact geometry and thus to distinguish between a set of grasped objects. With one data point from each finger, the object grasped by the hand can be identified. A clustering algorithm to find the correspondence for each grasped object is presented for both enveloping grasps and pinch grasps. A closed loop system uses a camera to detect approximate object locations. Compliance in the soft hand handles that uncertainty in addition to geometric uncertainty in the shape of the object.
This study proposes a modularized soft robotic arm with integrated sensing of human touches for physical human–robot interactions. The proposed robotic arm is constructed by connecting multiple soft ...manipulator modules, each of which consists of three bellow-type soft actuators, pneumatic valves, and an on-board sensing and control circuit. By employing stereolithography three-dimensional (3D) printing technique, the bellow actuator is capable of incorporating embedded organogel channels in the thin wall of its body that are used for detecting human touches. The organogel thus serves as a soft interface for recognizing the intentions of the human operators, enabling the robot to interact with them while generating desired motions of the manipulator. In addition to the touch sensors, each manipulator module has compact, soft string sensors for detecting the displacements of the bellow actuators. When combined with an inertial measurement unit (IMU), the manipulator module has a capability of estimating its own pose or orientation internally. We also propose a localization method that allows us to estimate the location of the manipulator module and to acquire the 3D information of the target point in an uncontrolled environment. The proposed method uses only a single depth camera combined with a deep learning model and is thus much simpler than those of conventional motion capture systems that usually require multiple cameras in a controlled environment. Using the feedback information from the internal sensors and camera, we implemented closed-loop control algorithms to carry out tasks of reaching and grasping objects. The manipulator module shows structural robustness and the performance reliability over 5,000 cycles of repeated actuation. It shows a steady-state error and a standard deviation of 0.8 mm and 0.3 mm, respectively, using the proposed localization method and the string sensor data. We demonstrate an application example of human–robot interaction that uses human touches as triggers to pick up and manipulate target objects. The proposed soft robotic arm can be easily installed in a variety of human workspaces, since it has the ability to interact safely with humans, eliminating the need for strict control of the environments for visual perception. We believe that the proposed system has the potential to integrate soft robots into our daily lives.
Soft robotics-based teleoperated robotic catheter systems hold great promise for improving the safety and efficacy of vascular interventional surgery (VIS). Despite advances, current robotic catheter ...systems actuated via cables have low stability, high force loss, lack of force sensing, and low stability when working against the dynamic cardiothoracic environment, all of which significantly reduce their effectiveness in clinical settings. Therefore, it is essential to equip the robotic catheters with a stabilizing mechanism (SM), a real-time force sensor, and the ability to expand the workspace without moving its body. This work introduces a new concept of a miniaturized soft robotic catheter (MSRC) for the VIS. The system consists of a soft manipulator for navigation and bending motion, a variable stiffness stabilizing mechanism (VSSM), and a soft force sensor for monitoring tool-tissue contact. By employing soft hydraulic filament artificial muscles (HFAMs), the flexible manipulator has an omnidirectional and extendable workspace and can generate a force of 0.375 N, which is monitored by a new HFAM-based sensor with a high sensitivity of about 10.7 KPa/N. The new VSSM can be deployed as a lantern form with a wide diameter range from 6 mm to 25 mm, potentially enhancing the catheter tip’s stability at various blood vessels (e.g., the inferior vena cava IVC) to perform VIS. The VSSM has a controllable deploying force and is capable of withstanding highly compressed forces with little deflection. The system feasibility to perform cardiac ablation is demonstrated with a simulated heart’s right atrium (RA), potentially offering a reliable tool for the treatment of atrial fibrillation (AF). The design, modelling, and fabrication of the device are also presented and followed by experimental characterizations, and ex-vivo tests.
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•A novel soft robotic catheter with integrated bending and extending, stabilizing, and sensing ability is developed.•An omnidirectional manipulator with extendable workspace for bending and extending motion is fabricated and characterized.•A stabilizing mechanism with a unique characteristic of variable stiffness is proposed to use for stabilizing the catheter.•A new and low-cost soft force sensor with high sensitivity for monitoring tool-tissue contacts is proposed.•Ex-vivo experiments of the system performing ablation in the heart's right atrium (RA) are conducted.