Soft Robotics Research Papers - Academia.edu (original) (raw)

2025, IEEE Robotics and Automation Letters

In this paper, we present an approach to study the behavior of compliant plates in granular media and optimize the performance of a robot that utilizes this technique for mobility. From previous work and fundamental tests on thin plate force generation inside granular media, we introduce an origami-inspired mechanism with non-linear compliance in the joints that can be used in granular propulsion. This concept utilizes one-sided joint limits to create an asymmetric gait cycle that avoids more complicated alternatives often found in other swimming/digging robots. To analyze its locomotion as well as its shape and propulsive force, we utilize granular Resistive Force Theory (RFT) as a starting point. Adding compliance to this theory enables us to predict the time-based evolution of compliant plates when they are dragged and rotated. It also permits more rational design of swimming robots where fin design variables may be optimized against the characteristics of the granular medium. This is done using a Python-based dynamic simulation library to model the deformation of the plates and optimize aspects of the robot's gait. Finally, we prototype and test robot with a gait optimized using the modelling techniques mentioned above.

2025, Materials Today

Soft robots built with active soft materials have been increasingly attractive. Despite tremendous efforts in soft sensors and actuators, it remains extremely challenging to construct intelligent soft materials that simultaneously actuate and sense their own motions, resembling living organisms' neuromuscular behaviors. This work presents a soft robotic strategy that couples actuation and strainsensing into a single homogeneous material, composed of an interpenetrating double-network of a nanostructured thermo-responsive hydrogel poly(N-isopropylacrylamide) (PNIPAAm) and a lightabsorbing, electrically conductive polymer polypyrrole (PPy). This design grants the material both photo/thermal-responsiveness and piezoresistive-responsiveness, enabling remotely-triggered actuation and local strain-sensing. This self-sensing actuating soft material demonstrated ultra-high stretchability (210%) and large volume shrinkage (70%) rapidly upon irradiation or heating (13%/ °C, 6-time faster than conventional PNIPAAm). The significant deswelling of the hydrogel network induces densification of percolation in the PPy network, leading to a drastic conductivity change upon locomotion with a gauge factor of 1.0. The material demonstrated a variety of precise and remotelydriven photo-responsive locomotion such as signal-tracking, bending, weightlifting, object grasping and transporting, while simultaneously monitoring these motions itself via real-time resistance change. The multifunctional sensory actuatable materials may lead to the next-generation soft robots of higher levels of autonomy and complexity with self-diagnostic feedback control.

2025, Advanced Materials

Stimuli‐responsive hydrogels can sense environmental cues and change their volume accordingly without the need for additional sensors or actuators. This enables a significant reduction in the size and complexity of resulting devices. However, since the responsive volume change of hydrogels is typically uniform, their robotic applications requiring localized and time‐varying deformations have been challenging to realize. Here, using addressable and tunable hydrogel building blocks—referred to as soft voxel actuators (SVAs)—heterogeneous hydrogel structures with programmable spatiotemporal deformations are presented. SVAs are produced using a mixed‐solvent photopolymerization method, utilizing a fast reaction speed and the cononsolvency property of poly(N‐isopropylacrylamide) (PNIPAAm) to produce highly interconnected hydrogel pore structures, resulting in tunable swelling ratio, swelling rate, and Young's modulus in a simple, one‐step casting process that is compatible with mass ...

2025, Advanced Materials

Biological systems can perform complex tasks with high compliance levels. This makes them a great source of inspiration for soft robotics. Indeed, the union of these fields has brought about bioinspired soft robotics, with hundreds of publications on novel research each year. This review aims to survey fundamental advances in bioinspired soft actuators and sensors with a focus on the progress between 2017 and 2020, providing a primer for the materials used in their design.

2025, Proceedings of the National Academy of Sciences of the United States of America

Shape-programmable matter is a class of active materials whose geometry can be controlled to potentially achieve mechanical functionalities beyond those of traditional machines. Among these materials, magnetically actuated matter is particularly promising for achieving complex time-varying shapes at small scale (overall dimensions smaller than 1 cm). However, previous work can only program these materials for limited applications, as they rely solely on human intuition to approximate the required magnetization profile and actuating magnetic fields for their materials. Here, we propose a universal programming methodology that can automatically generate the required magnetization profile and actuating fields for soft matter to achieve new time-varying shapes. The universality of the proposed method can therefore inspire a vast number of miniature soft devices that are critical in robotics, smart engineering surfaces and materials, and biomedical devices. Our proposed method includes t...

2025, International Journal of Automotive and Mechanical Engineering

In recent years, soft actuator has been extensively developed in robotic research. This type of robot is expected to work with human with its flexible and adaptable advantage. The actuator material is soft, light, safe and high compliant. Due to these factors, soft McKibben is of interest as an actuator for this research for bending application. This paper introduces a variant bending analysis of a soft body manipulated using soft McKibben actuators. A series of 1.80 mm width with the length of 120.0 mm McKibben actuator is used to control the bending motion. The design consists of four McKibben actuators arranged in parallel and compacted in a soft body. The bending behavior was evaluated using an experimental test with a variety of pneumatic input pressure and length section on the actuator. The experiment showed that the bending angle was influenced by the segmentation length of the actuator, where the segmentation length and increased input pressure also allow more bending on th...

2025, Frontiers in Neurorobotics

Philosophical and theoretical debates on the multiple realisability of the cognitive have historically influenced discussions of the possible systems capable of instantiating complex functions like memory, learning, goal-directedness, and decision-making. These debates have had the corollary of undermining, if not altogether neglecting, the materiality and corporeality of cognition—treating material, living processes as “hardware” problems that can be abstracted out and, in principle, implemented in a variety of materials—in particular on digital computers and in the form of state-of-the-art neural networks. In sum, the matter in se has been taken not to matter for cognition. However, in this paper, we argue that the materiality of cognition—and the living, self-organizing processes that it enables—requires a more detailed assessment when understanding the nature of cognition and recreating it in the field of embodied robotics. Or, in slogan form, that the matter matters for cogniti...

2025, Journal of NeuroEngineering and Rehabilitation

Background Assistive hand exoskeletons are promising tools to restore hand function after cervical spinal cord injury (SCI) but assessing their specific impact on bimanual hand and arm function is limited due to lack of reliable and valid clinical tests. Here, we introduce the Berlin Bimanual Test for Tetraplegia (BeBiTT) and demonstrate its psychometric properties and sensitivity to assistive hand exoskeleton-related improvements in bimanual task performance. Methods Fourteen study participants with subacute cervical SCI performed the BeBiTT unassisted (baseline). Thereafter, participants repeated the BeBiTT while wearing a brain/neural hand exoskeleton (B/NHE) (intervention). Online control of the B/NHE was established via a hybrid sensorimotor rhythm-based brain-computer interface (BCI) translating electroencephalographic (EEG) and electrooculographic (EOG) signals into open/close commands. For reliability assessment, BeBiTT scores were obtained by four independent observers. Bes...

2025

Background: Assistive hand exoskeletons are promising tools to restore hand function after cervical spinal cord injury (SCI) but assessing their specific impact on bimanual hand and arm function is limited due to lack of reliable and valid clinical tests. Here, we introduce the Berlin Bimanual Test for Tetraplegia (BeBiTT) and demonstrate its sensitivity to brain/neural hand exoskeleton(B/NHE)-related improvements in bimanual task performance. Methods: Fourteen study participants with subacute cervical SCI performed the BeBiTT unassisted (baseline). Thereafter, participants repeated the BeBiTT while wearing a B/NHE (intervention). Online control of the B/NHE was established via a hybrid sensorimotor rhythm-based brain-computer interface (BCI) translating electroencephalographic (EEG) and electrooculographic (EOG) signals into open/close commands. For reliability assessment, BeBiTT scores were obtained by four independent observers. Besides internal consistency analysis, construct va...

2025, Advanced Science

This paper presents a material programming approach for designing 4D-printed self-shaping material systems based on biological role models. Plants have inspired numerous adaptive systems that move without using any operating energy; however, these systems are typically designed and fabricated in the form of simplified bilayers. This work introduces computational design methods for 4D-printing bio-inspired behaviors with compounded mechanisms. To emulate the anisotropic arrangement of motile plant structures, material systems are tailored at the mesoscale using extrusion-based 3D-printing. The methodology is demonstrated by transferring the principle of force generation by a twining plant (Dioscorea bulbifera) to the application of a self-tightening splint. Through the tensioning of its stem helix, D. bulbifera exhibits a squeezing force on its support to provide stability against gravity. The functional strategies of D. bulbifera are abstracted and translated to customized 4D-printed material systems. The squeezing forces of these bio-inspired motion mechanisms are then evaluated. Finally, the function of self-tightening is prototyped in a wrist-forearm splint-a common orthotic device for alignment. The presented approach enables the transfer of novel and expanded biomimetic design strategies to 4D-printed motion mechanisms, further opening the design space to new types of adaptive creations for wearable assistive technologies and beyond.

2025, Soft robotics

Possessing a sense of touch is fundamental for robots to operate outside controlled environments. Nevertheless, pressure and force-sensing technologies are still less mature than vision or proprioception solutions in commercial robots. In this study we present a novel spatially resolved force sensor that allows dynamic measurement of both the intensity and the direction of forces exerted on a custom-shaped surface. Originally designed for biomechanics of arboreal primates, this sensor meets several challenges in engineering robotic skin. Of importance, its ability to measure tangential forces would be instrumental for robotic hands to grasp deformable and unknown objects. Based on optical measurements of deformations, this array sensor presents a soft, biocompatible, weather resistant body, immune to electromagnetic interferences. Central to the costeffectiveness of this solution is an architecture where a single image sensor handles hundreds of force measurement points simultaneously. We demonstrate the performance of this sensor in reconstructing normal and slantwise forces on a flat prototype adapted to forces under 3 N. Finally, we discuss the broad range of possible customizations and extensions for applications in biomechanics and robotics.

2025

Despite more than three decades since the beginning of Additive Manufacturing (AM), many challenges and issues prevent the industrialization of this technology. In fact, productivity is related to repetitive production of the same part under the same fabrication conditions. Currently, it is difficult to guarantee this repetitive production due to uncertainty issues, which represents the main obstacle of AM industrialization. In this paper, the uncertainty issues can be divided into two levels. The first level is related to the used AM machine itself which can be considered as robot of 3 degrees of freedom (x, y and z). In addition to its movement in three directions, this robot (AM machine) extrudes melted materials. The second level is related to the associated robots with 3D printing machines. In addition to summarizing some previous works and reviews, this mini review has the objective to provide new ideas to develop new strategies to overcome some uncertainty issues to contribute to the industrialization of AM technology. Furthermore, it paves the way to establish a concurrent AM / robotics loop in order to use AM for robotics and robotics for AM. The different developments should lead to elaborating Industrialization Standard for AM (IS4AM) where the different findings and recommendations can be classified in logical ways to deal with different AM techniques and materials.

2025, ACS Applied Materials & Interfaces

Aquatic actuators based on the light-to-work conversion are of paramount significance for the development of cutting-edge fields including robots, micromachines, and intelligent systems. Herein, we report the design and synthesis of near-infrared light-driven hydrogel actuators through loading with lightweight polydopamine-modified hollow glass microspheres (PDA-HGMPs) into responsive poly(Nisopropylacrylamide) (PNIPAM) hydrogels. These PDA-HGMPs can not only function as an excellent photothermal agent but also accelerate the swelling/desewlling of hydrogels due to their reconstruction for polymer gel skeleton, which speeds up the response rate of hydrogel actuators. The resulting hydrogel actuator shows controlled movements under light illumination, including complex self-propellant and floating/sinking motions. As the proof-of-concept demonstrations, a self-sensing robot is conceptualized by integrating the PDA-HGMP-containing hydrogel actuator with an ultrathin and miniature pressure sensor. Hopefully, this work can offer some important insights into the research of smart aquatic soft actuators, paving the way to the potential applications in emerging fields including micromachines and intelligent systems.

2025, Polymers for Advanced Technologies

Dielectric elastomer actuators rely on Coulomb forces for their actuation. They are promising candidates when it comes to the manufacture of electrically driven soft and lightweight robotic devices, which can undergo large movement. However, their commercial availability and hence their technological relevance are still rather limited due to several reasons: in-depth material knowhow in terms of electrical and mechanical behavior required; materials have to be available in thin sheets; complicated and error prone fabrication; limited design freedom. In order to change this, this paper presents a soft dielectric actuator fully produced by fused filament fabrication. Additive manufacturing with conventional fused filament fabrication machines offers the potential for the production of personalized dielectric actuators which are easily accessible and comparably cheap. The only requirement is a fused filament fabrication printer with multi-material capability. Focusing on a mass customization of the 3D printed actuators, exclusively commercially available devices and filaments without any modifications are used. In particular, the 3D printed prototypes are characterized in terms of the maximum displacement depending on the electrode printing direction. As a showcase example, a soft dielectric gripper made of two 3D printed actuators is developed. Comparable with other dielectric elastomer actuators, a maximum displacement of 42% is reached.

2025, Soft Robotics

This article describes a soft suction cup end effector with squid-inspired suction generation and an octopusinspired cup design that uses a dielectric elastomer actuator (DEA) to generate suction for adhesion. The fabrication process for the end effector is described in detail, and a mechanical model for generated pressure differential as a function of voltage is presented. When actuated, the DEA exerts an electrostatic stress on the walls of the end effector, resulting in pressure reduction in its water-filled cavity. The actuator is soft, flexible, and creates suction without a reliance on typical DEA elements such as rigid supporting structures and elastomer prestrain. It does not require net fluid flux out of the sucker, allowing faster attachment and easier release. It can be actuated underwater and has been validated with pull-off tests. The sucker generates a pressure differential of 3.63 -0.07 kPa (-SD) when driven at 10.75 kV in water and should reach a 4.90 kPa pressure differential when energized at its theoretical failure point of 12.4 kV. Data normalized by the input voltage show that 90% of the maximum pressure differential can be achieved within 50 ms of voltage application. Weighing less than 30 g in air, this elastomer end effector is capable of pulling with a force of 8.34 -0.10 N (-SD) and reversibly lifting 26.7 times its own mass underwater when actuated at 10.75 kV.

2025, Applied Bionics and Biomechanics

Traditional robots have rigid underlying structures that limit their ability to interact with their environment. For example, conventional robot manipulators have rigid links and can manipulate objects using only their specialised end effectors. These robots often encounter difficulties operating in unstructured and highly congested environments. A variety of animals and plants exhibit complex movement with soft structures devoid of rigid components. Muscular hydrostats (e.g. octopus arms and elephant trunks) are almost entirely composed of muscle and connective tissue and plant cells can change shape when pressurised by osmosis. Researchers have been inspired by biology to design and build soft robots. With a soft structure and redundant degrees of freedom, these robots can be used for delicate tasks in cluttered and/or unstructured environments. This paper discusses the novel capabilities of soft robots, describes examples from nature that provide biological inspiration, surveys t...

2025, International Journal of Electrical and Computer Engineering (IJECE)

The mobile robot is an intelligent device that can achieve many tasks in life. For autonomous, navigation based on the line on the ground is often used because it helps the robot to move along a predefined path, simplifies the path planning, and reduces the computational load. This paper presents a method for navigating the four-wheel mobile robot to track a line based on a deep Q-network as a control algorithm to desire the action of the mobile robot and a camera as a feedback sensor to detect the line. The control algorithm uses a convolution neural network (CNN) to generate the mobile robot action, defined as an agent of deep Q-network. CNN uses images from the camera to define the state of the deep Q network. The simulations are performed based on Gazebo software which includes a 3D environment, mobile robot model, line, and Python programming. The results demonstrate the high-performance tracking of mobile robots with complex line trajectories, achieving errors of less than 100 px, which is compared with the traditional vision method (VNS), the MSE of the proposal method is 0.0264 lower than VNS with 0.0406. Showcases proved convincingly that effectiveness suggested a control approach.

2025, IEEE Transactions on Robotics

Contact modeling between a soft robot and its environment is challenging due to soft robots' compliance and the difficulty of embedding sensors. Current modeling methods are computationally expensive and require highly accurate material characterization to produce useful results. In this article, we present a contact model that utilizes linear complementarity and Hencky bar-chain methods, and requires only static images to efficiently predict the interaction between actuator and environment. These methods have yet to be introduced to the soft robotics community for modeling robots that deform due to eigenstrains or strains not caused by external forces. We validated our model using a custom experimental setup and computer vision algorithm on 3-mm OD, 90-mm long, tube-like actuators. Our results indicated a 1.06% difference in shape between model and experiment, with computation times in 10 s of ms-three to four orders of magnitude faster than nonlinear gradient descent. Additionally, the error in interaction forces between the model and experiment decreased as pressure increased, with an average error magnitude of 45% and 21% for pressures at the low and high ends of the tested range, respectively.

2025, Journal of Medical Devices

2025, MOCAST Conference Proceedings

Stroke is estimated to affect about 5,500,000 people annually worldwide, with 60-80% of survivors left with unilateral weakness in their extremities. Other diseases and accidents also contribute to limited mobility and paralysis for millions of patients worldwide. This paper presents the design of a wearable glove that has the capability to curl, extend and resist finger movement by providing forces similar to those produced by agonist and antagonist muscles. The aim of the device is to assist with physical rehabilitation while also providing haptic feedback to the patient. This is achieved by utilizing a pneumatic soft robotic actuation system to provide the curling force (agonistic movement) and a tendon-based pulley system to provide the opposing force (antagonistic movement). This technological choice allows for flexibility as well as gentle, soft feeling of the device, reducing the chances of injury during the rehabilitation process. The design aims to enrich existing physical rehabilitation repetitive motion training routines, utilizing haptic feedback and limiting the range of finger curling utilizing simulated tendons.

2025

In recent years, the need for highly controlled, non-invasive manipulation of micro-scale objects has become increasingly evident across various biomedical applications. From cell-level interventions to advanced surgical techniques, the challenge lies in achieving both precision and adaptability without direct contact or mechanical interference. This paper introduces a novel conceptual framework aimed at addressing this challenge through a dynamic, controllable system that utilizes principles of physics and intelligent engineering design to influence motion at microscopic levels. While the underlying mechanisms remain proprietary, the core idea revolves around a non-contact method of actuation that aligns with modern demands in minimally invasive biomedical procedures.

2025

Traditional planners need a complete representation of the initial state of the environment they are acting on. In complex and dynamic settings, however, the information describing the state of the environment can be too big to be e ciently stored and updated, and changes frequently. Thus, the representation the planner has of the real world it is acting on can become obsolete during or after plan construction. The corresponding o-line plan execution can fail. We propose a solution where a planner and an executing ...

2025, Robotics

This paper is an extension of our previous work about a modular anthropomorphic robotic hand with soft enhancements focusing on simultaneous pinch grasp and suction-based object manipulations. The base structure is a tendon-driven robotic hand comprising five fingers and a palm. Each finger consists of two rigid links covered with soft enhancements. The soft enhancements are like the skin and tissues of the robotic hand. The tip of the finger is equipped with a suction module which can be actuated by regulating negative pressure to the soft layers. While our previous work dealt with the rationale behind and the structure of the modular design with kinematic analysis, this paper focuses on analyzing two specific capabilities of the gripper-pinch grasp and suction modality. Experiments validate that the proposed gripper together with the soft enhancement layers is capable of performing delicate single finger suction-based manipulation tasks and two-finger pinch grasp tasks.

2025, Panorama Rubber (English)

Daetwyler Rubber increasingly relies on numeric simulation techniques in product and process development. Using finite element analysis, the functionality of new elastomer components can be studied at an early phase. This speeds... more

2025, IEEE Transactions on Biomedical Engineering

This randomized controlled feasibility study investigates the ability for clinical application of the Brain-Computer Interface-based Soft Robotic Glove (BCI-SRG) incorporating activities of daily living (ADL)oriented tasks for stroke rehabilitation. Methods: Eleven recruited chronic stroke patients were randomized into BCI-SRG or Soft Robotic Glove (SRG) group. Each group underwent 120-minute intervention per session comprising 30-minute standard arm therapy and 90-minute experimental therapy (BCI-SRG or SRG). To perform ADL tasks, BCI-SRG group used motor imagery-BCI and SRG, while SRG group used SRG without motor imagery-BCI. Both groups received 18 sessions of intervention over 6 weeks. Fugl-Meyer Motor Assessment (FMA) and Action Research Arm Test (ARAT) scores were measured at baseline (week 0), post-intervention (week 6), and follow-ups (week 12 and 24). In total, 10/11 patients completed the study with 5 in each group and 1 dropped out. Results: Though there were no significant intergroup differences for FMA and ARAT during 6-week intervention, the improvement of FMA and ARAT seemed to sustain beyond 6-week intervention for BCI-SRG group, as compared with SRG control. Incidentally, all BCI-SRG subjects reported a sense of vivid movement of the stroke-impaired upper limb and 3/5 had this

2025, Biomimetics

Multimodal brain-computer interfaces (BCIs) that combine electrical features from electroencephalography (EEG) and hemodynamic features from functional nearinfrared spectroscopy (fNIRS) have the potential to improve performance. In this paper, we propose a multimodal EEG-and fNIRS-based BCI system with soft robotic (BCI-SR) components for personalized stroke rehabilitation. We propose a novel method of personalizing rehabilitation by aligning each patient's specific abilities with the treatment options available. We collected 160 single trials of motor imagery using the multimodal BCI from 10 healthy participants. We identified a confounding effect of respiration in the fNIRS signal data collected. Hence, we propose to incorporate a breathing sensor to synchronize motor imagery (MI) cues with the participant's respiratory cycle. We found that implementing this respiration synchronization (RS) resulted in less dispersed readings of oxyhemoglobin (HbO). We then conducted a clinical trial on the personalized multimodal BCI-SR for stroke rehabilitation. Four chronic stroke patients were recruited to undergo 6 weeks of rehabilitation, three times per week, whereby the primary outcome was measured using upper-extremity Fugl-Meyer Motor Assessment (FMA) and Action Research Arm Test (ARAT) scores on weeks 0, 6, and 12. The results showed a striking coherence in the activation patterns in EEG and fNIRS across all patients. In addition, FMA and ARAT scores were significantly improved on week 12 relative to the pre-trial baseline, with mean gains of 8.75 ± 1.84 and 5.25 ± 2.17, respectively (mean ± SEM). These improvements were all better than the Standard Arm Therapy and BCI-SR group when retrospectively compared to previous clinical trials. These results suggest that personalizing the rehabilitation treatment leads to improved BCI performance compared to standard BCI-SR, and synchronizing motor imagery cues to respiration increased the consistency of HbO levels, leading to better motor imagery performance. These results showed that the proposed multimodal BCI-SR holds promise to better engage stroke patients and promote neuroplasticity for better motor improvements.

2025, Open Access Journal of Science and Technology

2025, ACS Applied Materials & Interfaces

Wearable strain sensors are essential for the realization of applications in the broad fields of remote healthcare monitoring, soft robots, immersive gaming, among many others. These flexible sensors should be comfortably adhered to skin and capable of monitoring human motions with high accuracy, as well as exhibiting excellent durability. However, it is challenging to develop electronic materials that possess the properties of skin-compliant, elastic, stretchable, and selfhealable. This work demonstrates a new regenerative polymer complex composed of poly(2acrylamido-2-methyl-1-propanesulfonic acid) (PAAMPSA), polyaniline (PANI) and phytic acid (PA) as a skin-like electronic material. It exhibits ultrahigh stretchability (1935%), repeatable autonomous self-healing ability (repeating healing efficiency > 98%), and quadratic response to strain (R 2 > 0.9998), linear response to flexion bending(R 2 > 0.9994) -outperforming current reported wearable strain sensors. The deprotonated polyelectrolyte, multivalent anion, and doped conductive polymer, under ambient conditions, synergistically construct a regenerative dynamic network of polymer complex crosslinked by hydrogen bonds and electrostatic interactions, which enables ultrahigh stretchability and repeatable self-healing. Sensitive strain-responsive geometric and piezoresistive mechanisms of the material owing to the homogenous and viscoelastic nature provide excellent linear responses to omnidirectional tensile strain and bending deformations. Furthermore, this material is scalable and simple to process in an environmentally-friendly manner, paving the way for the next generation flexible electronics.

2025, Journal of the Robotics Society of Japan

2025, 3D SCEEER Conference

Rehabilitation robots have become one of the main technical instruments that Treat disorder patients in the biomedical engineering field. The robotic glove for the rehabilitation is basically made of specialized materials which can be designed to help the post-stroke patients. In this paper, a review of the different types of robotic glove for Rehabilitation have been discussed and summarized. This study reviews a different mechanical system of robotic gloves in previous years. The selected studies have been classified into four types according to the Mechanical Design: The first type is a tendon-driven robotic glove. The second type of robotic glove works with a soft actuator as a pneumatic which is operated by air pressure that passes through a plastic pipe, pressure valves, and air compressor. The third type is the exoskeleton robotic gloves this type consists of a wearable mechanical design that can used a finger-based sensor to measure grip strength or is used in interactive vi...

2025

This project describes resistance-based soft sensors filled with liquid metal, which permit measurements of large strains (0% to 110%), associated with small forces of less than 30 Newtons. This work also demonstrates a methodology for wireless transfer of these strain measurements without connected electrodes. These sensors allow intermittent detection of pressure on soft membranes with low force. Adapting these sensors for passive wireless pressure sensing will eliminate the need for embedded batteries, and will allow the sensors to transmit pressure data through non-conductive materials including glass and acrylic. The absence of batteries allows us to embed these sensors into materials for long-term use because the sensors only use passive analog circuit elements. We found the oxidation of the liquid metal (eutectic gallium indium) plays a role in the repeatability of the soft sensors. We investigated how the oxidation layer affected the behavior of the sensor by encapsulating materials (silicone, fluorosilicone, and PVC) with varied permeabilities to oxygen. We measured the effects of mechanical loading on the oxidation layer and the effects of wireless inductive coupling on the oxidation layer. We concluded our research by investigating the effects of embedding selfresonant circuits into PDMS. Efforts to design engineered systems with soft materials are growing field with progress in soft robotics, epidermal electronics, and wearable electronics. In the field of soft robotics, polydimethylsiloxane (PDMS)-based grippers are capable of picking up delicate objects because their form-fitting properties allow them to conform to the shape of objects more easily than conventional robotic grippers. Epidermal devices also use PDMS as a substrate to hold electronic components such as radios, sensors, and power supply circuits. Additionally, PDMS-based soft sensors can monitor human motion with liquid metal embedded within microchannels. Passive wireless sensors have applications in structural health monitoring and medical health monitoring. Doctors can take wireless blood pressure measurements inside arteries to monitor the progression of heart disease. Glaucoma patients can use this technology to monitor the pressure in their eyes to track the progression of the disease.

2025

1,2,3,4 Student, Department of Mechanical Engineering, Christ Deemed to be University, Bangalore, Karnataka, India... more

1,2,3,4 Student, Department of Mechanical Engineering, Christ Deemed to be University, Bangalore, Karnataka, India ----------------------------------------------------------------------***--------------------------------------------------------------------Abstract Researchers and scientists alike have been searching for inexpensive, robust, and a comparable substitute which integrate the functionality, compliance, versatility, and strength of human arms. Some measure of progress has been achieved in case of metal or alloy made prostheses or orthotics, composite layered bionic arms etc. However these models are hard to design and costly to make. Also, though they exhibit excellent strength characteristics their range of movements is to a major degree constrained and limited. In lieu of such difficulties, the largely untapped area of soft robotic elements offers a feasible and viable solution. Materials such as soft elastomer and rubbers on integration with other available materials s...

2025

This study focuses on the development of durable cutting technology to improve efficiency in textile manufacturing, specifically for cutting thin fabric straps like shoulder straps for female undergarments. The research aims to design a cutting blade and mechanism actuated by a pneumatic actuator and controlled by an HMI-based system. It addresses the need for a durable cutting edge and proposes a method to model and design an effective cutting process. The study involves examining the mechanical properties of fabrics, frictional coefficients, and cutting mechanisms. It also explores the selection of actuation techniques and control systems, including the development of a ladder program to operate the mechanism. The methodology includes designing the blade using parametric curves, calculating cutting forces, and determining the wedge angle and blade thickness. Simulations ensure the blade's strength meets the requirements for cutting force. The research identifies factors affecting cutting tool effectiveness, such as wedge angle, curvature of the edge, and blade thickness, which influence the cutting force needed for different fabric piles. The study contributes a solution that can be applied in the textile industry for productive and cost-effective cutting strategies.

2025

Soft robotics has emerged as a trending field recently due to the traditional rigid robotics failure in their applications requiring flexibility and adaptability in constrained environments. One of the crucial parameters that defines a soft robot is its material and the redundant degrees of freedom. The use of soft materials allows for continuous deformation which in turn, enables structures with ranges of motion limited only by the properties of the material [1]. Such materials that are used for the fabrication of the soft manipulators are Silicone Rubber, Elastomers (PDMS), SMAs, Thermoplastic Elastomers, etc. Among the applications that require flexibility one significant scenario is the inspection of pipelines in water sprinkler systems, which often involves navigating through pipelines with diameters as narrow as 4-8 inches. This research aims to design and analyse a soft robotic manipulator specifically for in-situ operations within these confined spaces. The manipulator incorporates a Shape Memory Alloy (SMA) spring, actuated by voltage, and a pneumatically actuated PneuNet structure to facilitate precise and flexible movements. The main focus of this research is on detailing the design process of the manipulator and highlighting the customization of the SMA spring. The manufacturability and material selection for the PneuNet structure are also discussed, alongside simulations are also performed using Abaqus CAE to ensure the validity of the manipulator design.

2025, International Journal of Mathematical and Computational Sciences

A vibration isolation technology for precise position control of a rotary system powered by two permanent magnet DC (PMDC) motors is proposed, where this system is mounted on an oscillatory frame. To achieve vibration isolation for this system, active damping and disturbance rejection (ADDR) technology is presented which introduces a cooperation of a main and an auxiliary PMDC, controlled by discrete-time sliding mode control (DTSMC) based schemes. The controller of the main actuator tracks a desired position and the auxiliary actuator simultaneously isolates the induced vibration, as its controller follows a torque trend. To determine this torque trend, a combination of two algorithms is introduced by the ADDR technology. The first torque-trend producing algorithm rejects the disturbance by counteracting the perturbation, estimated using a model-based observer. The second torque trend applies active variable damping to minimize the oscillation of the output shaft. In this practice, the presented technology is implemented on a rotary system with a pendulum attached, mounted on a linear actuator simulating an oscillation-transmitting structure. In addition, the obtained results illustrate the functionality of the proposed technology.

2025, Academia Engineering

Marine resource exploration and environmental monitoring are essential for the sustainable development of oceans. However, the high cost of conventional submersibles has hindered their widespread application. In this paper, we evaluate the performance and cost of second and third generations of submersibles and propose a novel fourth-generation submersible concept based on an advanced real-time fish monitoring platform. Through a comprehensive SWOT (strengths, weaknesses, opportunities, and threats) analysis, we conduct a systematic comparison between the third and fourth generations of submersibles, highlighting their respective advantages and limitations. Additionally, the research identifies and examines the critical technical and operational challenges associated with the implementation of fourth-generation submersible platforms. This may bridge the gap from robotics to biology.

2025, Hand X-Ray Interpretation , Medical imaging , Medical Physics , Lecture of X-Ray Anatomy Course , Lectures of Clinical and Physics of Imaging , LinkedIn , Physics of Diagnostic Radiology , X-Ray Physics , X-Ray Anatomy , Health Science , Health Physics

- The fingers, thumb and metacarpals are the most common sites of injury in the skeletal system. The importance of the functional hand is obvious, therefore prompt diagnosis and subsequent treatment is vital - Plain radiography is... more

2025, Soft Matter

Reconfigurable actuators are designed based on chitosan and pNipam which has the capability to attain precise and programmable actuation. The current approach offers a feasible way to fabricate soft actuators with repeatable and... more

2025, Actuators

The design and construction of a soft robot are challenging tasks on their own. When the robot is supposed to operate without a tether, it becomes even more demanding. While a tethered operation is sufficient for a stationary use, it is impractical for wearable robots or performing tasks that demand a high mobility. Choosing and implementing an on-board pneumatic pressure source are particularly complex tasks. There are several different pressure generation methods to choose from, each with very different properties and ways of implementation. This review paper is written with the intention of informing about all pressure generation methods available in the field of soft robotics and providing an overview of the abilities and properties of each method. Nine different methods are described regarding their working principle, pressure generation behavior, energetic considerations, safety aspects, and suitability for soft robotics applications. All presented methods are evaluated in the...

2025, Robotics and Biomimetics

Soft robotics is an emerging field in the robotics community which deals with completely new types of robots. However, often new soft robotic designs depend on the ingenuity of the engineer rather being systematically derived. For this reason, in order to support the engineer in the design process, we present a design methodology for general technical systems in this paper and explain it in depth in the context of soft robotics. The design methodology consists of a combination of state-of-the-art engineering concepts that are arranged in such a way that the engineer is guided through the design process. The effectiveness of a systematic approach in soft robotics is illustrated on the design of a new gecko-inspired, climbing soft robot.

2025, Actuators (MDPI)

Light-actuated microbots have been studied as a viable tool for interacting with micro/nano environments. Considering their applicability to a wide range of biomedical applications, novel designs, fabrication techniques, and control methodologies are being developed. Especially, micro/nanoscale three-dimensional fabrication techniques have opened many possibilities for developing microbots with complex geometries using resins as materials. Here, we developed microbots that can be actuated with tightly focused laser beams to be used in targeted drug delivery, cell poking, and cell characterization studies. These microbots were fabricated in batches using two-photon polymerization (TPP). Each microbot utilizes a deposited metal layer inside its body to manipulate convective microfluidic flows. Additionally, micro-sized end effectors allow them to make measurable physical contact with biological objects. Their expected performance was evaluated using numerical simulations with the use of multiphysics software. Furthermore, laser-induced loading and unloading of micro-sized cargo show their capability for in vitro applications.

2025, Journal of Student Research

In an effort to improve rehabilitation devices, the applications of soft robotics technologies to prosthetics and physical therapy was explored, particularly due to the benefits of the inherent properties of soft materials. A conceptual design for a soft robotics device prototype is proposed to assist with physical therapy for wrist tendonitis and arthritis, carpal tunnel syndrome, fractures and sprains, and compromised motor skills due to chronic stroke. The device assists in four motions that are commonly performed in wrist therapy: flexion, extension, and rotation (clockwise and counterclockwise) using soft pneumatic actuators to guide movements. The distinct directions were achieved by varying the lateral and radial strain limiting layers. The device uses embodied intelligence to make the device dynamically adaptable in real time, allowing for a customizable recovery process. A detailed model of the device was developed and the viability of the design was assessed using a suite ...

2025, Journal of NeuroEngineering and Rehabilitation

Background Soft, wearable, powered exoskeletons are novel devices that may assist rehabilitation, allowing users to walk further or carry out activities of daily living. However, soft robotic exoskeletons, and the more commonly used rigid exoskeletons, are not widely adopted clinically. The available evidence highlights a disconnect between the needs of exoskeleton users and the engineers designing devices. This review aimed to explore the literature on physiotherapist and patient perspectives of the longer-standing, and therefore greater evidenced, rigid exoskeleton limitations. It then offered potential solutions to these limitations, including soft robotics, from an engineering standpoint. Methods A state-of-the-art review was carried out which included both qualitative and quantitative research papers regarding patient and/or physiotherapist perspectives of rigid exoskeletons. Papers were themed and themes formed the review’s framework. Results Six main themes regarding the limi...

2025, Ionic Polymer Metal Composites for Sensors and Actuators

This chapter encapsulates the design and fabrication paradigm of a soft compliant ionic polymer metal composite (IPMC) actuated three-finger gripper material to polydimethyl siloxane (PDMS). The PDMS based IPMC actuated gripper has been designed in such a manner that it is capable of handling macro and micro objects. The selection of PDMS based finger for gripper design was ensured through experiments from four different PDMS finger designs. Maximum compliance of the PDMS finger is desirable for the gripper, keeping this as a criterion, one of the four fingers, has been selected for the presently reported three-finger gripper. In human hand, the proximal, intermediate and distal phalanges activate with each other in a synergistic way through inter-phalangeal articulations. This phenomenon is inculcated using PDMS for compliance in the finger and IPMC as muscle actuation. Overall specification of three finger gripper is reported in this chapter.

2025, Mechatronics

Soft-robotics is gradually emerging as one of the promising fields of research and innovation. Owing to the blend of material-chemistry and conventional mechanics, complex motions have been successfully generated by flexible polymeric composites that act upon external activation stimuli. However, lack of robust deterministic models which can command reliable actuator performance, hinder their widespread deployments in diverse paradigms. The present article seeks to address the argument by modelling Ionic Polymer Metal Composites (IPMC) as multi-segmented chains of connected rigid bodies. A Cyclic-Coordinate-Descent (CCD) based Inverse Kinematic solver is employed to resolve the redundancy, by minimizing an objective function in joint space at gradual iterative steps. The algorithm is validated for its ability to model dissimilarly doped polymeric curvatures bearing distinct spatial postures. The 2-D shape estimation problem is addressed to generate patterns akin to original IPMCs for deployment on potential applications that anticipate a foresight of actuator geometry.

2025, Sensors and Actuators A: Physical

Ionic Polymer Metal Composites (IPMC) have emerged as an actuator for gripping soft as well as rigid objects, owing to their compliance and good scalability. Their use in precision gripping necessitates the absence of any ambivalence in its characterization to ensure grasp stability. This article proposes an alternative approach to model IPMCs, contrary to prior attempts that have employed cantilever deflection theories. The bending patterns of the actuator soaked in distilled water and LiCl solution are studied using a Tractrix based hyper-redundant kinematic algorithm. Two distinct gripper designs comprising of a conventional two jaw as well as a modified passive jaw gripper have been investigated to ascertain their traversed workspaces in the aforementioned mediums. A prior knowledge of this working-area ensures an effective design of target-specific gripper configurations adept to negotiate objects with varied surface profiles. The results obtained after experiments indicate that IPMCs infused in LiCl solution exhibit a characteristic curvilinearity, suited for ensuring surface contact with the object. However the ones hydrated in de-ionized water demonstrate linear bending, apt for generating point contact. Though the passive-jaw gripper showcases a smaller workspace with respect to the active ones, yet it conveys a vital information regarding the contact force exerted on an object surface by the polymer jaw.

2025, arXiv (Cornell University)

Soft robotic actuators are safe and adaptable devices with inherent compliance, which makes them attractive for manipulating delicate and complex objects. Researchers have integrated stiff materials into soft actuators to increase their force capacity and direct their deformation. However, these embedded materials have largely been pre-prescribed and static, which constrains the actuators to a predetermined range of motion. In this work, electroadhesive (EA) clutches integrated on a single-chamber soft pneumatic actuator (SPA) provide local programmable stiffness modulation to control the actuator deformation. We show that activating different clutch patterns inflates a silicone membrane into pyramidal, round, and plateau shapes. Curvatures from these shapes are combined during actuation to apply forces on both a 3.7 g and 820 g object along five different degrees of freedom (DoF). The actuator workspace is up to 12 mm for light objects. Clutch deactivation, which results in local elastomeric expansion, rapidly applies forces up to 3.2 N to an object resting on the surface and launches a 3.7 g object in controlled directions. The actuator also rotates a heavier, 820 g, object by 5 degrees and rapidly restores it to horizontal alignment after clutch deactivation. This actuator is fully powered by a 5 V battery, AA battery, DC-DC transformer, and 4.5 V (63 g) DC air pump. These results demonstrate a first step towards realizing a soft actuator with high DoF shape change that preserves the inherent benefits of pneumatic actuation while gaining the electrical controllability and strength of EA clutches. We envision such a system supplying human contact forces in the form of a low-profile sit-to-stand assistance device, bed-ridden patient manipulator, or other ergonomic mechanism.