Electronic skins are essential for real-time health monitoring and tactile perception in robots. Although the use of soft elastomers and microstructures have improved the sensitivity and ...pressure-sensing range of tactile sensors, the intrinsic viscoelasticity of soft polymeric materials remains a long-standing challenge resulting in cyclic hysteresis. This causes sensor data variations between contact events that negatively impact the accuracy and reliability. Here, we introduce the Tactile Resistive Annularly Cracked E-Skin (TRACE) sensor to address the inherent trade-off between sensitivity and hysteresis in tactile sensors when using soft materials. We discovered that piezoresistive sensors made using an array of three-dimensional (3D) metallic annular cracks on polymeric microstructures possess high sensitivities (> 10⁷ Ω · kPa−1), low hysteresis (2.99 ± 1.37%) over a wide pressure range (0–20 kPa), and fast response (400 Hz). We demonstrate that TRACE sensors can accurately detect and measure the pulse wave velocity (PWV) when skin mounted. Moreover, we show that these tactile sensors when arrayed enabled fast reliable one-touch surface texture classification with neuromorphic encoding and deep learning algorithms.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
Abstract
Human skin is a self-healing mechanosensory system that detects various mechanical contact forces efficiently through three-dimensional innervations. Here, we propose a biomimetic ...artificially innervated foam by embedding three-dimensional electrodes within a new low-modulus self-healing foam material. The foam material is synthesized from a one-step self-foaming process. By tuning the concentration of conductive metal particles in the foam at near-percolation, we demonstrate that it can operate as a piezo-impedance sensor in both piezoresistive and piezocapacitive sensing modes without the need for an encapsulation layer. The sensor is sensitive to an object’s contact force directions as well as to human proximity. Moreover, the foam material self-heals autonomously with immediate function restoration despite mechanical damage. It further recovers from mechanical bifurcations with gentle heating (70 °C). We anticipate that this material will be useful as damage robust human-machine interfaces.
•A 3-DOF end-effector module is developed for industrial finishing tasks.•The position controlled bandwidth is beyond 100 Hz.•Position based compliance control is implemented for environmental ...interactions.•Experimental results meet industrial requirements.
A strategy to improve industrial finishing applications using commercial robotic arms is presented in this paper. An end-effector is designed and prototyped as the mini manipulator, and is mounted at the end-point of a commercial robotic arm to form a macro-mini manipulator system. The developed end-effector has properties of fast response and high resolution in position control and force control. Position based force/impedance control algorithms of the end-effector are introduced, targeting on applications of polishing and deburring. Experiments are conducted by employing the integrated macro-mini manipulator system and the results are presented.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPUK, ZRSKP
Stretchable electronics have advanced rapidly and many applications require high repeatability and robustness under various mechanical deformations. It has been described here that how a highly ...stretchable and reliable conductor composite made from helical copper wires and a soft elastomer, named eHelix, can provide mechanically robust and strain‐insensitive electronic conductivity for wearable devices. The reversibility of the mechanical behavior of the metal‐elastomer system has been studied using finite element modeling methods. Optimal design parameters of such helical metal‐elastomer structures are found. The scaling of multiple copper wires into such helical shapes to form a Multi‐eHelix system is further shown. With the same elastomer volume, Multi‐eHelix has more conductive paths and a higher current density than the single‐eHelix. Integrations of these eHelix stretchable conductors with fabrics showed wearable displays that can survive machine‐washes and hundreds of mechanical loading cycles. The integration of the eHelix developed by us with a wearable optical heart rate sensor enabled a wearable health monitoring system that can display measured heart rates on clothing. Furthermore, Multi‐eHelix conductors are used to connect flexible printed circuit boards and piezoresistive sensors on a tactile sensing glove for the emerging sensorized prosthetics.
A multi‐wire highly stretchable and mechanically robust conductor composite, named Multi‐eHelixes, is introduced to provide mechanical robustness and strain‐insensitive electronic conductivity. The stretchable conductor system is made from helical copper wires embedded within soft elastomers with optimal design parameters. These stretchable conductors can serve as reliable interconnects for various wearable healthcare devices and robotic applications.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The development of modern robotics has triggered increasing interest in developing artificial tactile sensory systems. However, the tactile mechanism in the design process has been highly limited to ...experimental tests that are expensive and time-consuming. This work is concerned with the development of using virtual tests for tactile sensory response prediction and design, which includes numerical simulation settings, database creation, response regression and interpolation, and sensor sensitivity designs. Experimental verifications and numerical demonstrations are performed based on the NUS NeuTouch sensors. The potential of using virtual tests to design new tactile sensors to improve response linearity is illustrated.
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•Tactile response prediction and design using virtual tests is proposed with demonstration on NUS NeuTouch sensors.•The framework consists of numerical simulations, database creation, response regression and interpolation.•The potential of using virtual tests to design new tactile sensors for improving response linearity is illustrated.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPUK, ZAGLJ, ZRSKP
We examined the associations of gestational diabetes mellitus (GDM) and women's weight status from pre-pregnancy through post-delivery with the risk of developing dysglycaemia impaired fasting ...glucose, impaired glucose tolerance, and type 2 diabetes (T2D) 4-6 years post-delivery. Using Poisson regression with confounder adjustments, we assessed associations of standard categorisations of prospectively ascertained pre-pregnancy overweight and obesity (OWOB), gestational weight gain (GWG) and substantial post-delivery weight retention (PDWR) with post-delivery dysglycaemia (n = 692). Women with GDM had a higher risk of later T2D relative risk (95% CI) 12.07 (4.55, 32.02) and dysglycaemia 3.02 (2.19, 4.16) compared with non-GDM women. Independent of GDM, women with pre-pregnancy OWOB also had a higher risk of post-delivery dysglycaemia. Women with GDM who were OWOB pre-pregnancy and had subsequent PDWR (≥ 5 kg) had 2.38 times (1.29, 4.41) the risk of post-delivery dysglycaemia compared with pre-pregnancy lean GDM women without PDWR. No consistent associations were observed between GWG and later dysglycaemia risk. In conclusion, women with GDM have a higher risk of T2D 4-6 years after the index pregnancy. Pre-pregnancy OWOB and PDWR exacerbate the risk of post-delivery dysglycaemia. Weight management during preconception and post-delivery represent early windows of opportunity for improving long-term health, especially in those with GDM.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Humans display the remarkable ability to sense the world through tools and other held objects. For example, we are able to pinpoint impact locations on a held rod and tell apart different textures ...using a rigid probe. In this work, we consider how we can enable robots to have a similar capacity, i.e., to embody tools and extend perception using standard grasped objects. We propose that vibro-tactile sensing using dynamic tactile sensors on the robot fingers, along with machine learning models, enables robots to decipher contact information that is transmitted as vibrations along rigid objects. This paper reports on extensive experiments using the BioTac micro-vibration sensor and a new event dynamic sensor, the NUSkin, capable of multi-taxel sensing at 4 kHz. We demonstrate that fine localization on a held rod is possible using our approach (with errors less than 1 cm on a 20 cm rod). Next, we show that vibro-tactile perception can lead to reasonable grasp stability prediction during object handover, and accurate food identification using a standard fork. We find that multi-taxel vibro-tactile sensing at a sufficiently high sampling rate (above 2 kHz) led to the best performance across the various tasks and objects. Taken together, our results provide both evidence and guidelines for using vibro-tactile perception to extend tactile perception, which we believe will lead to enhanced competency with tools and better physical human-robot interaction.
This work presents the simple and rapid fabrication of a polymer-based microfluidic prototype manufactured by rolling up thin films of polymer. The thin films were fabricated via a casting method and ...rolled up around a center core with the aid of plasma activation to create a three-dimensional (3D) spiral microchannel, hence reducing the time and cost of manufacture. In this work, rolled-up devices with single or dual fluidic networks fabricated from a single or two films were demonstrated for heat sink or heat exchanger applications, respectively. The experimental results show good heat transfer in the rolled-up system at various flow rates for both heat sink and heat exchanger devices, without any leakages. The rolled-up microfluidic system creates multiple curved channels, allowing for the generation of Dean vortices, which in turn lead to an enhancement of heat and mass transfer and prevention of fouling formation. These benefits enable the devices to be employed for many diverse applications, such as heat-transfer devices, micromixers, and sorters. To our knowledge, this work would be the first report on a microfluidic prototype of 3D spiral microchannel made from rolled-up polymeric thin film. This novel fabrication approach may represent the first step towards the development of a pioneering prototype for roll-to-roll processing, permitting the mass production of polymer-based microchannels from single or multiple thin films.
Vitamin D deficiency is common in pregnant women. There is scarce information in the Asia-Pacific region on the understanding of vitamin D screening and supplementation in pregnancy among health care ...professionals.
We performed a cross-sectional study among health care professionals who are part of the Integrated Platform for Research in Advancing Metabolic Health outcomes of Women and Children (IPRMAHO) international study group on their understanding and perception of Vitamin D screening and supplementation in pregnancy. The cross-sectional survey comprised 4 main sections: demographics, existing policies, nutrient supplementation in pregnancy and various practices on screening, treatment and perceptions, with a total of 22 questions. A total of 15 responses were obtained from attendees from distinct health facilities across eleven participating Asia-Pacific countries.
Majority of the surveyed hospitals (11/15, 78.6 %) did not have a national policy or regional guideline regarding Vitamin D screening and supplementation in pregnancy. More than half of respondents were (9/14, 64.3 %) were unsure of the percentage of women seen with Vitamin D deficiencies each year and were unsure of Vitamin D dosage prescribed to pregnant women with (8/15, 53.3 %) or without (6/14, 42.9 %) Vitamin D deficiency. Vitamin D was rarely prescribed in pregnancy when compared to other nutrient supplements such as folic acid and iron. Majority of respondents (9/11, 72.7 %) indicated that their hospital did not screen for Vitamin D deficiencies in pregnancy, even amongst high risk pregnant women. Nevertheless, majority of respondents indicated a need (12/15, 80.0 %) for a guideline or consensus regarding Vitamin D screening and supplementation in pregnancy.
While majority of the surveyed hospitals did not have a national policy or regional guideline regarding Vitamin D screening and supplementation in pregnancy, majority of respondents indicated a need for the policy or guideline. There were varying clinical knowledge gaps and different perceptions on Vitamin D screening and supplementation in pregnancy among healthcare professionals.
•Lack of screening for vitamin D deficiency in pregnancy, especially high-risk pregnancies.•General consensus regarding need for policy regarding vitamin D screening and supplementation.•Vitamin D was rarely prescribed in pregnancy when compared to other nutrient supplements such as folic acid and iron.•Supplementation is generally preferred for those with low serum vitamin D and high risk profile.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPUK, ZAGLJ, ZRSKP
Background: Women with a history of gestational diabetes mellitus (GDM) have a 7-fold increased risk for subsequent development of type 2 diabetes mellitus (T2DM). Continuous glucose monitoring ...systems (CGMS) and exercise trackers have not been thoroughly explored in any Asian postpartum diabetes prevention studies. Objective: The Integrated Hyperglycaemia Incentivised Postnatal Surveillance (I-HIPS) study aims to investigate the efficacy of a personalized lifestyle intervention programme using wearables along with physical activity (PA) and diet modification to achieve healthy weight loss in postpartum women with history of GDM.
Methods: Women were randomized to receive the intervention or standard medical care. The intervention group received a CGM sensor and exercise tracker, along with nutrition, exercise and personalized goal-setting workshops. Anthropometric measures (weight, BMI and waist circumference (WC)) and PA assessed using the International Physical Activity Questionnaire were examined between the two arms at the 6-month follow-up. Changes in dietary behaviors in the intervention group were assessed using a validated 6P tool.
Results: Twenty-six recruited women had completed the 6-month follow-up. At 6-month, compared with the controls, women receiving intervention achieved a mean difference in the reduction of weight by 0.5 kg, BMI by 0.2 kg/m2 and WC by 0.8cm (p>0.05). The intervention group had increased PA (mean difference: +990 MET mins/week), compared to the controls (mean difference: +298 MET mins/week) (p>0.05) at 6-month. Between baseline and 6-month, women in the intervention group showed a reduction in the frequency of snack and beverage intakes (p=0.01).
Conclusion: Preliminary findings suggest a trend toward better health outcomes in the intervention group with improved dietary behaviour.
Disclosure
P.Quah: None. N.Razali: None. S.M.H.Chai: None. F.Fadzully: None. L.W.K.Ryan: None. C.Ku: None. S.Loy: None. K.Tan: None.
Funding
National Medical Research Council of Singapore (MOH-000504-03)
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