Soft Touch Research Articles

Micro-extrusion foaming fabricating porous polyester elastomeric fiber for using in radiative cooling fabrics

Climate change has unleashed relentless global heatwaves, posing grave threats to the physical and mental well-being of outdoor laborers and the smooth functioning of society. Porous polymeric fibers exhibit promising potential in personal thermal management for wearable fabrics. Nevertheless, the absence of an environmentally friendly, cost-effective, and efficient method for producing the desired porous fibers remains a formidable challenge. Here, we introduce a pioneering micro-extrusion foaming technique for crafting elastic porous fibers endowed with dense longitudinally oriented cell morphologies, remarkable porosity of 69 % and elongation of 668 %. The technique enabled the continuous production of porous fibers exceeding 3000 m in length in a single operation, with fiber diameters controlled to approximately 0.25–0.55 mm. Fabrics woven from the elastic porous fiber offered a soft touch, proficiently reflecting more than 90.0 % of incident solar radiation and emitting 91.9 % of absorbed heat radiation, thereby achieving a theoretical radiant cooling power of 111.46 W/m2 on sunlit days. Leveraging the controllable and scalable attributes of micro-extrusion foaming, the porous fiber is primed for practical deployment and expansion into diverse wearable applications.

Valenced tactile information is evoked by neutral visual cues following emotional learning

Abstract Learning which stimuli in our environment co-occur with painful or pleasurable events is critical for survival. Previous research has established the basic neural and behavioral mechanisms of aversive and appetitive conditioning; however, it is unclear precisely what information content is learned. Here we examined the degree to which aspects of the unconditioned stimulus (US)—sensory information versus affective salience—are transferred to the conditioned stimulus (CS). To decode what stimuli features (e.g., valence vs. discriminative somatosensation) are represented in patterns of brain activation elicited during appetitive (soft touch) and aversive (painful touch) conditioning to faces, a novel approach to using modeling with representational similarity analysis (RSA) based on theoretically driven representational patterns of interest (POIs) was applied to fMRI data. Once associations were learned through conditioning, globally, the CS reactivated US representational patterns showing conditioning-dependent reactivation in specific high-order brain regions: In the dorsal anterior cingulate cortex, the CS reactivated patterns associated with the affective salience of the US—suggesting that, with affective conditioning, these regions carry forward the affective associations of the experience.

A perspective on mechanoluminescence and multipiezo in ferroelectric materials

The discovery of innovative mechanoluminescence materials of SrAl2O4 and ZnS, which emit repeatable light [repeatable mechanoluminescence (ML), hereafter simply ML] even by soft touch, has trigged intense research interest in material/device/system development for applications across various fields. This perspective presents an overview of the crystal structures, mechanisms, and ML behaviors of most promising systems, namely, SrAl2O4-, ZnS-, LiNbO3-, and Sr3Sn2O7-based ferroelectric materials. These multipiezo materials, which simultaneously exhibit intrinsic piezoluminescence (true elastic deformation induced ML and no friction effect) and piezoelectricity, show distinct and valuable characteristics by integrating mechanical force, electric field, and light for stress sensing and other applications. Recent studies indicated the critical role of crystal structure, doping, and piezoelectric properties in achieving robust and reliable ML performance. These findings suggest that ML materials hold substantial promise for applications in stress/force sensing, structural health monitoring, mechanically activated lighting, and advanced imaging techniques. Further investigation and advancement of multipiezo materials could yield breakthroughs, further augmenting their usefulness across various industries and scientific domains. Exploring ferroelectric ML materials offer new prospects for developing advanced materials with unique electro-mechano-optical properties.

High Tech and Soft Touch: Mind-Body Medicine and Technology Can Be Co-Evolutionary Forces.

High Tech and Soft Touch: Mind-Body Medicine and Technology Can Be Co-Evolutionary Forces.

A Review on Soft Ionic Touch Point Sensors

A touch sensor is an essential component in meeting the growing demand for human‐machine interfaces. These sensors have been developed in wearable, attachable, and even implantable forms to acquire a wide range of information from humans. To be applied to the human body, sensors are required to be biocompatible and not restrict the natural movement of the body. Ionic materials are a promising candidate for soft touch sensors due to their outstanding properties, which include high stretchability, transparency, ionic conductivity, and biocompatibility. Here, this review discusses the unique features of soft ionic touch point sensors, focusing on the ionic material and its key role in the sensor. The touch sensing mechanisms include piezocapacitive, piezoresistive, surface capacitive, piezoelectric, and triboelectric and triboresistive sensing. This review analyzes the implementation hurdles and future research directions of the soft ionic touch sensors for their transformative potential.

Ionic Liquid Enabled Transparent Heterogeneous Elastomers for Soft Electronics

AbstractDielectric elastomer (DE), as an electrically active soft material, has enabled stretchable electronics, electronic skins, artificial muscles, biomimetic soft robots, and non‐magnetic motors. High permittivity is urgently desired for increasing the sensitivity of DE sensors and lowering the driving voltage of DE actuators. However, existing efforts for significantly enhanced permittivity is usually achieved at the expense of transparency of the DE by compositing external fillers, which limits the applications in optoelectronics, such as displays, touch screens, artificial eyes, etc. Here, by utilizing of transparent functional filler, ionic liquid micro‐droplet, and precise matching the refractive index with polydimethylsiloxane (PDMS) elastomer matrix, heterogeneous composites with high transparency and high permittivity are obtained simultaneously. The composites are transparent in the visible range (transmittance, 80%–95%). The permittivity reaches up to 22, which is more than seven times higher than the original value of the elastomer matrix. Moreover, the arbitrary deformability of ionic liquid filler endows the composites with better stretchability (300%) and much lower elastic modulus (0.5 MPa, about a quarter the value of PDMS), which is beneficial for soft electronics. Based on the as‐prepared high‐performance composites, high sensitivity and transparent soft sensors and touch panels have been realized, as well as wireless transmission of sensing signals.

A soft touch with electron beams: Digging out structural information of nanomaterials with advanced scanning low energy electron microscopy coupled with deep learning

Nanostructured materials continue to find applications in various electronic and sensing devices, chromatography, separations, drug delivery, renewable energy, and catalysis. While major advancements on the synthesis and characterization of these materials have already been made, getting information about their structures at sub-nanometer resolution remains challenging. It is also unfortunate to find that many emerging or already available powerful analytical methods take time to be fully adopted for characterization of various nanomaterials. The scanning low energy electron microscopy (SLEEM) is a good example to this. In this report, we show how clearer structural and surface information at nanoscale can be obtained by SLEEM, coupled with deep learning. The method is demonstrated using Au nanoparticles-loaded mesoporous silica as a model system. Moreover, unlike conventional scanning electron microscopy (SEM), SLEEM does not require the samples to be coated with conductive films for analysis; thus, not only it is convenient to use but it also does not give artifacts. The results further reveal that SLEEM and deep learning can serve as great tools to analyze materials at nanoscale well. The biggest advantage of the presented method is its availability, as most modern SEMs are able to operate at low energies and deep learning methods are already being widely used in many fields.

Soft Actuator with Biomass Porous Electrode: A Strategy for Lowering Voltage and Enhancing Durability.

Electroactive artificial muscles with deformability have attracted widespread interest in the field of soft robotics. However, the design of artificial muscles with low-driven voltage and operational durability remains challenging. Herein, novel biomass porous carbon (BPC) electrodes are proposed. The nanoporous BPC enables the electrode to provide exposed active surfaces for charge transfer and unimpeded channels for ion migration, thus decreasing the driving voltage, enhancing time durability, and maintaining the actuation performances simultaneously. The proposed actuator exhibits a high displacement of 13.6 mm (bending strain of 0.54%) under 0.5 V and long-term durability of 99.3% retention after 550,000 cycles (∼13 days) without breaks. Further, the actuators are integrated to perform soft touch on a smartphone and demonstrated as bioinspired robots, including a bionic butterfly and a crawling robot (moving speed = 0.08 BL s-1). This strategy provides new insight into the design and fabrication of high-performance electroactive soft actuators with great application potential.

Development of Fabric Surface Texture and Design Natural Dyed Hand-Woven Patterns in the Northern Regio

This article aims to 1) Study the potential production, structure and consumer demand of hand-woven products with natural dyed fabric. 2) Develop the surface texture of fabric and design patterns of hand-woven fabrics that are suitable for textile manufacturing and meet the lifestyle of consumers. 3) Produce the prototypes of hand-woven fabrics which developed surface texture and pattern. 4) Assess consumer satisfaction with prototype product. The target group of this study is entrepreneurs of hand-woven fabrics using natural dyes in the northern region, there are 5 groups with 110 people in total, including the Ampan cotton group, Dao Mang Hemp Fabric Community Enterprise Group, Ban Pa Ngiu Karen Weaving Group, Ban Na Hang Karen Weaving Group, and Ban Huai Ta Community Enterprise Group. The research methods utilized in this study were focus groups, questionnaires, and collaboration with community entrepreneurs in developing and producing woven fabrics. The results show that the 15 woven fabrics developed by the researcher had better surface textures, with a soft touch and good recovery against wrinkles. Additionally, the new weaving structures resulted in new patterns. The researchers designed and produced 21 styles of contemporary casual wear, folk costume, and dress, which meet the requirements of consumers who value eco-friendliness, culture, healthy lifestyles, and minimalism. Furthermore, textile products such as bags, satchels, and hats were also designed and produced, emphasizing the fineness of sewing and the community product standards. Finally, the satisfaction of consumers with the prototype products was assessed, with an average satisfaction level of 4.84 out of 5.

Additive manufacturing of thermoplastic elastomer structures using dual material core-shell filaments

Filament-based flexible material extrusion additive manufacturing is highly desirable yet faces critical challenges such as limited print resolution and repeatability. To enhance printability of a thermoplastic elastomer (TPE), a series of core-shell filaments comprising a TPE shell (Shore hardness 75 A) and a rigid ABS core are fabricated, with the ABS volume fraction varying from 11% to 78%. The presence of an ABS core imparts rigidity to the filament to inhibit buckling and allow for successful high-fidelity 3D printing. Rheological characterizations of TPE and ABS using capillary and parallel-plate viscometry point to the optimized extrusion parameters suitable for filament coextrusion, printability, and wettability between the print interfaces. Complex benchmark geometries are printed to verify the print resolution. Printed specimens with less than 20% ABS preserve the shore hardness of 75 A, providing flexibility and a soft touch to the printed structures. Izod impact, 3-point bending, and tensile tests reveal tunable mechanical properties of parts printed in z-direction with ABS+TPE filaments. Lower ABS content exhibits higher flexibility and impact resistance, while higher ABS imparts higher stiffness and tensile strength. Notably, the parts printed with 30–40% ABS exhibit higher toughness and impact strength than specimens composed of ABS or TPE alone. Lastly, a coil spring printed with a ABS+TPE filament exhibits reversible extension up to 120 mm, at least twice the reversible extension of an ABS-printed coil spring.

Monitoring Soft Shape Surface Deformation via Optical Images for the Distinction of Contact State

The deformability of elastomer surfaces offers the opportunity to capture multimodal physical information, which opens up possibilities for applications in intelligent interactive systems and flexible electronics. Accurately identifying the surface deformation of elastomers has been a key issue for understanding the contact state in a soft touch. However, effective monitoring of the deformed surface topography during soft‐touch processes is difficult due to the complexity of interfacial deformation. Herein, the optical detection method based on an ideal diffuse reflection model is proposed to monitor the deformation of the elastomer, enabling the acquisition of a spatially continuous deformation of the surface in a soft touch. This optical system with the parallel incident light can distinguish the elastomers’ surface deformation field by constructing the correlation between the reflected light irradiance and the surface deformation angle. This method allows for the perception of the contact area. Through the deep learning method, the recognition rate can reach more than 84.24% when there are slight differences in the contact of objects with different geometric shapes. The design offers valuable insights for contact state detection tasks and facilitates soft‐touch sensing functions through the high precision of optical signal acquisition.

Long-Term Sensory Function 3 years after Minimally Invasive Repair of Pectus Excavatum with Cryoablation

IntroductionMinimally invasive repair of pectus excavatum (MIRPE) with intercostal nerve cryoablation (Cryo) decreases length of hospitalization and opioid use, but long-term recovery of sensation has been poorly described. The purpose of this study was to quantify long-term hypoesthesia and neuropathic pain after MIRPE with Cryo. MethodsA prospective cohort study was conducted single-institution of patients ≤21 years who presented for bar removal. Consented patients underwent chest wall sensory testing and completed neuropathic pain screening. Chest wall hypoesthesia to cold, soft touch, and pinprick were measured as the percent of the treated anterior chest wall surface area (TACWSA); neuropathic pain was evaluated by questionnaire. ResultsThe study enrolled 47 patients; 87% male; median age 18.4 years. The median bar dwell time was 2.9 years. A median of 2 bars were placed; 80.9% were secured with pericostal sutures. At enrollment, 46.8% of patients had identifiable chest wall hypoesthesia. The mean percentage of TACWSA with hypoesthesia was 4.7 ± 9.3% (cold), 3.9 ± 7.7% (soft touch), and 5.9 ± 11.8% (pinprick). Hypoesthesia to cold was found in 0 dermatomes in 62%, 1 dermatome in 11%, 2 dermatomes in 17% and ≥3 dermatomes in 11%. T5 was the most common dermatome with hypoesthesia. Neuropathic symptoms were identified by 13% of patients; none required treatment. ConclusionIn long-term follow up after MIRPE with Cryo, 46.8% of patients experienced some chest wall hypoesthesia; the average TACWSA with hypoesthesia was 4–6%. Hypoesthesia was mostly limited to 1–2 dermatomes, most commonly T5. Chronic symptomatic neuropathic pain was rare. Level of evidenceLevel IV.

Air Preheater Performance Analysis: Installation of Soft Seal Material to Improve Air Preheater Leakage

Air preheaters are used in thermal power plants to preheat combustion air before it enters the furnace by recovering and using waste heat from the flue gas that is supposed to be exhausted at the stack to reduce the work needed by the furnace to combust fuel and improve the boiler efficiency. Air preheater leakage is the bypassing of the cooler ambient air into the flue gas side, reducing the temperature needed to heat the heating elements which transfers the heat into the air side. This negatively impacts the heat transfer effectiveness of the air preheater and the overall thermal efficiency of the plant. This paper aims to review the effectiveness of the soft touch seals applied in a Ljungstrom Type Regenerative Air Preheater installed in a 455 MW (net) Coal-Fired Thermal Power Plant situated in Mauban, Quezon Province in the Philippines in reducing the air preheater leakage through calculations and analysis in compliance with the ASME Performance Test Code to ensure accuracy and repeatability.

Improving the Uniform Distribution of Nano-Ag in Al-Doped ZnO Film to Enhance Its Application in Soft Touch Sensing Electrodes

Improving the Uniform Distribution of Nano-Ag in Al-Doped ZnO Film to Enhance Its Application in Soft Touch Sensing Electrodes

A soft tactile sensing array with high sensitivity based on MWCNTs-PDMS composite of hierarchically porous structure

The advancement of wearable tactile sensors that involves with high sensitivity under ultra-low pressures is crucial for varieties of human-machine interactive applications, like smart phones, healthcare monitoring, and electronic skins. Here in this paper, a soft capacitive tactile sensing array is introduced based on hierarchically porous multi-walled carbon nanotubes (MWCNTs)-polydimethylsiloxane composite, which leads to sensitivity improvement attributing to a synergistic effect of the hierarchically porous elastomer and conductive MWCNTs supplements. The proposed device exhibits superior pressure-sensing performances, with high sensitivity (3.58 kPa−1) under small mechanical stimuli (<80 Pa), broad measuring range (0–265 kPa), fast response time (<45 ms), good repeatability, minimum limit of detection (<10 Pa), as well as low-hysteresis, allowing efficient sensing of pressure from all types of sources, from vulnerable signals such as human breathing, artery and venous pulses, and soft human finger touch to possible brutal variations such as sudden change of object weight or prompt collide. Moreover, extensive body attached experiments confirm that the soft tactile sensing array is fully human compatible and capable for a variety of human-machine interfaces and health monitoring applications.

Highly Sensitive Soft Pressure Sensors for Wearable Applications Based on Composite Films with Curved 3D Carbon Nanotube Structures.

Soft pressure sensors based on 3D microstructures exhibit high sensitivity in the low-pressure range, which is crucial for various wearable and soft touch applications. However, it is still a challenge to manufacture soft pressure sensors with sufficient sensitivity under small mechanical stimuli for wearable applications. This work presents a novel strategy for extremely sensitive pressure sensors based on the composite film with local changes in curved 3D carbon nanotube (CNT) structure via expandable microspheres. The sensitivity is significantly enhanced by the synergetic effects of heterogeneous contact of the microdome structure and changes of percolation network within the curved 3D CNT structure. The finite-element method simulation is used to comprehend the relationships between the sensitivity and mechanical/electrical behavior of microdome structure under the applied pressure. The sensor shows an excellent sensitivity (571.64 kPa-1 ) with fast response time (85ms), great repeatability, and long-term stability. Using the developed sensor, a wireless wearable health monitoring system to avoid carpel tunnel syndrome is built, and a multi-array pressure sensor for realizing a variety of movements in real-time is demonstrated.

Implementation of Massage Efflaurage Method To Reduce Labor Pain During The Active Phase I

Childbirth is normal in every pregnant woman, but many pregnant women cannot bear the pain during normal labor. Severe labor pain if not treated immediately can endanger the mother because it can cause the mother's condition to become unstable so that it can cause labor complications. Many methods can be done to reduce labor pain, one of which is the massage effleurage method, this method is very easy to apply, does not require expensive costs and can be done directly by mothers who give birth or family. How to do this method is by giving massage or soft touch on the mother's abdomen above the symplysis until it goes to the fundus and the right and left sides of the mother's abdomen are done repeatedly when contractions come. This community service implementation activity is carried out to increase the knowledge of pregnant women in preparing for childbirth, especially in overcoming labor pain when I. The activity was carried out in March 2023 at the obstetrics polyclinic of Granmed Lubuk Pakam Hospital, the participants of the activity were all pregnant women who visited ANC at Grandmed Hospital as many as 27 people, before being given implementation the majority of participants did not know about the massage effleurage method and after being given 100% implementation (27 people) participants could do massage effleurage. It is hoped that with the holding of this community service activity, pregnant women can have a more mature preparation to carry out normal labor and it is recommended that they can apply it during normal labor, especially during labor.

Modulation of Piezo1 influences human skin architecture and oxytocin expression.

Throughout our existence, the skin senses and analyses the mechanical forces imposed by the environment. In response to these environmental forces, skin can deform itself and achieve a biological response. The subsequent cutaneous plasticity emerges from mechanical properties arising from the collective action of the skin cells, particularly keratinocytes, that govern the tensile strength via cell-to-cell adhesions and via cell-matrix adhesion structures. In addition to serving as force-bearing entities, keratinocytes respond to forces by activating signalling pathways to control their own fate and function. To detect and adapt to mechanical signals, keratinocytes possess a panel of sensory receptors and junctional intercellular structures. Mechanically activated ion channel Piezo1 has been described as a force sensor and as being involved in pleasant touch perception. In this study, relationships between Piezo1 modulation and oxytocin synthesis were investigated. The expression of Piezo1 in the skin was studied and compared with the expression of TRPV1. Dooku1 antagonist and Jedi1 agonist were used to modulate Piezo1. The level of E-cadherin and oxytocin was monitored in ex vivo skin biopsies by immunodetection. Taken together, our results illustrate the major role of mechanosensitive ion channel Piezo1 in skin barrier integrity, and in peripheral oxytocin synthesis in the skin. In conclusion, this study highlights the relationships between pleasant touch, soft touch and local oxytocin synthesis.

Dorsal Column Bedside Examination Test: Tips for the Neurosurgical Resident.

The dorsal column medial lemniscus (DCML) system is a sensory pathway of the central nervous system; it carries sensations of soft touch, vibration, proprioception, two-point discrimination, and pressure from the skin and joints. The clinical signs of the DCML pathway lesions include loss of soft touch, vibratory sense, proprioception, discrimination sense, and a positive Rhomberg test. Diseases that affect this pathway are usually degenerative, for example, spinal cord degeneration due to vitamin B12 deficiency; it can also be affected by trauma or infarction of the posterior spinal artery causing posterior cord syndrome. This video manuscript provides a step-by-step examination technique of the dorsal column examination, specially catered for Malaysian medical students and trainees. A series of videos show the techniques for soft touch sensation examination, examination of the vibratory sense, examination of the joint position sense, examination of two-point discrimination and the Rhomberg test. We hope that students can adhere to these techniques and apply them in their daily neurological assessments.

Bullet-titling in twenty-first century China: bullet-like tactility, soft touch and diachronic simultaneity

This article studies the popular bullet-titling practice in contemporary China – typing and sending a layer of horizontally scrolling comments superimposed onto moving images. It first explicates bullet-titling practice as a retaliatory action against the tactile effects of moving images, reconceptualizing cinema’s tactile quality and recovering its association with bullet-like intensity through the notion of tacti(ca)lity. Tracing the changed perception of touch in relation to the emergence of the touchscreen interface, the author then delineates the transformation of bullet-titles from offensive weapons against the optical attacks of moving images to a venue for real-time conversation and communication among spectator-cum-bullet-titlers. The article ends with a discussion of bullet-titles’ construction of pseudo-real time, which constitutes a viewing community of ‘diachronic simultaneity’ that assimilates all temporally and geographically dispersed spectators into the unfolding ‘now’ of video playback. This ‘nowness’ reconciles contemporary media consumption’s contradictory demands for globalized simultaneity and individualized flexibility, obliterating us anew.