Ravinder S. Dahiya

University of Glasgow | UofG · James Watt School of Engineering

Transfer printing has been reported recently as a viable route for electronics on flexible substrates. The method involves transferring micro-/macrostructures such as wires or ultra-thin chips from Si (silicon) wafers to the flexible substrates by using elastomeric transfer substrates such as poly(dimethylsiloxane) (PDMS). A major challenge in this...

Printing sensors and electronics over flexible substrates are an area of significant interest due to low-cost fabrication and possibility of obtaining multifunctional electronics over large areas. Over the years, a number of printing technologies have been developed to pattern a wide range of electronic materials on diverse substrates. As further e...

Starting from human ??sense of touch,?? this paper reviews the state of tactile sensing in robotics. The physiology, coding, and transferring tactile data and perceptual importance of the ??sense of touch?? in humans are discussed. Following this, a number of design hints derived for robotic tactile sensing are presented. Various technologies and t...

Email Print Request Permissions Save to Project This paper presents ultra-thin silicon chips (flex-chips) on flexible foils, realized through post-processing steps such as wafer thinning, dicing, and transferring the thinned chips to flexible polyimide foils. The cost effective chemical etching is adopted for wafer thinning and the transfer pri...

A wide variety of tactile (touch) sensors exist today for robotics and related applications. They make use of various transduction methods, smart materials and engineered structures, complex electronics, and sophisticated data processing. While highly useful in themselves, effective utilization of tactile sensors in robotics applications has been s...

Nano/microstructures of compound semiconductors such as gallium arsenide (GaAs) demonstrate enormous potential for advanced photonic technologies as they provide realistic means for miniaturization of optoelectronic devices that feature better performance and low power consumption. However, intimately integrating them onto flexible substrates is ch...

Touch is a complex sensing modality owing to large number of receptors (mechano, thermal, pain) nonuniformly embedded in the soft skin all over the body. These receptors can gather and encode the large tactile data, allowing us to feel and perceive the real world. This efficient somatosensation far outperforms the touch-sensing capability of most o...

An electronic skin (e-skin) for the next generation of robots is expected to have biological skin-like multimodal sensing, signal encoding, and preprocessing. To this end, it is imperative to have high-quality, uniformly responding electronic devices distributed over large areas and capable of delivering synaptic behavior with long- and short-term...

Strain sensors with wide‐range stretchability, good sensitivity, high gauge factor, and reliability are needed for several applications. Herein, stretchable strain sensors capable of operating over multi‐strain range and having an excellent gauge factor are presented. The systematic study, carried out with different combinations of elastomer, condu...

The current state of the art in cognitive robotics, covering the challenges of building AI-powered intelligent robots inspired by natural cognitive systems. A novel approach to building AI-powered intelligent robots takes inspiration from the way natural cognitive systems—in humans, animals, and biological systems—develop intelligence by exploiting...

Accurate object pose estimation using multi-modal perception such as visual and tactile sensing have been used for autonomous robotic manipulators in literature. Due to variation in density of visual and tactile data, we previously proposed a novel probabilistic Bayesian filter-based approach termed translation-invariant Quaternion filter (TIQF) fo...

Three-dimensional (3D) object recognition is crucial for intelligent autonomous agents such as autonomous vehicles and robots alike to operate effectively in unstructured environments. Most state-of-art approaches rely on relatively dense point clouds and performance drops significantly for sparse point clouds. Unsupervised domain adaption allows t...

High‐performance flexible electronics developed with resource efficient printing route will transform the way future electronics is manufactured and used to advance applications such as healthcare, Internet of Things, wearables, consumer electronics, etc. Herein, an innovative approach is presented that involves, for the first time, the in‐tandem u...

This work presents a novel active visuo-tactile based framework for robotic systems to accurately estimate pose of objects in dense cluttered environments. The scene representation is derived using a novel declutter graph (DG) which describes the relationship among objects in the scene for decluttering by leveraging semantic segmentation and grasp...

Innovative methods to fabricate and integrate biodegradable high‐grade electronics on green substrates are needed for the next generation of robust high‐performance transient electronics. This is also needed to alleviate the growing problem of electronic waste (e‐waste). Herein, the authors present the n‐channel silicon (Si) nanoribbons‐based high‐...

This work presents a novel active visuo-tactile based framework for robotic systems to accurately estimate pose of objects in dense cluttered environments. The scene representation is derived using a novel declutter graph (DG) which describes the relationship among objects in the scene for decluttering by leveraging semantic segmentation and grasp...

Easy to use multifunctional wearable devices, with no wires hanging around, are needed for real time health monitoring at user's comfort. Herein, an inductor‐capacitor (LC) resonant tank‐based wireless pressure sensor, screen‐printed on an electrospun Poly‐L‐lactide (PLLA) nanofibers‐based flexible, biocompatible, and piezoelectric substrate is pre...

In recent years, efficient energy storage devices that exhibit superior power and energy densities have attracted major attention to meet the demands of emerging applications such as wearable systems. In this regard, supercapacitors (SCs) in various forms offer attractive solutions. The performance of SCs is highly dependent on the synthesis route...

Highly sensitive capacitive pressure sensors with wide detection range are needed for applications such as humanmachine interfaces, electronic skin in robotics, and health monitoring. However, it is challenging to achieve high sensitivity and wide detection range at the same time. Herein, we present an innovative approach to obtain a highly sensiti...

This paper presents ISFET array based pH-sensing system-on-ultra-thin-chip (SoUTC) designed and fabricated in 350 nm CMOS technology. The SoUTC with the proposed current-mode active-pixel ISFET circuit array is desined to operate at 2V and consumes 6.28 W per-pixel. The presented SoUTC exhibits low sensitivity to process, voltage, temperature and s...

This paper presents ultrathin chips (UTCs) based flexible tactile sensing system for dynamic contact pressure measurement. The device comprises of an AlN piezocapacitor based UTCs tightly coupled with another UTCs having metal-oxide-semiconductor field-effect transistors (MOSFETs). In this arrangement the AlN piezocapacitor forms the extended gate...

Estimation of pH is vital to assess the biochemical and biological processes in a wide variety of applications ranging from water to soil, health, and environment monitoring. This work reports a screen-printed flexible and disposable pH sensor using the impedimetric method. The pH sensor was fabricated by screen printing Graphene-Carbon modified Zi...

Stretchable electronics is one of the transformative pillars of future flexible electronics. As a result, the research on new passive and active materials, novel designs, and engineering approaches has attracted significant interest. Recent studies have highlighted the importance of new approaches that enable the integration of high-performance mat...

“Heterogeneous Integration” is a promising approach for high-performance hybrid flexible electronics that combine printed electronics and silicon technology. Despite significant progresses made by integrating rigid silicon chips on flexible substrates, the integration of flexible ultra-thin chips (UTCs) on flexible foils remains a challenge as they...

The ion‐sensitive field effect transistors (ISFETs), proposed little over 50 years ago, today make the most promising devices for lab‐on‐a‐chip, implantable, and point‐of‐care (POC) diagnostics. Their compatibility with CMOS (Complementary Metal Oxide Semiconductor) technology and the low cost through mass production have been the driving factors s...

lexible electronics with high-performance devices is crucial for transformative advances in several emerging and traditional applications. To address this need, herein we present p-type silicon (Si) nanoribbons (NR)-based high-performance field-effect transistors (FETs) developed using innovative Direct Roll Transfer Stamping (DRTS) process. First,...

Transfer printing of high mobility inorganic nanostructures, using an elastomeric transfer stamp, is a potential route for high-performance printed electronics. Using this method to transfer nanostructures with high yield, uniformity and excellent registration over large area remain a challenge. Herein, we present the ‘direct roll transfer’ as a si...

Triboelectric nanogenerators (TENGs) are flexible, efficient, and cost-effective energy harvesters. Here, we develop high-performance ferroelectric-assisted TENGs using electrospun fibrous surfaces based on P(VDF-TrFE) with dispersed BaTiO3 (BTO) nanofillers in either cubic (CBTO) or tetragonal (TBTO) form. TENGs with three types of tribo-negative...

Printing is a promising method for the large-scale, high-throughput, and low-cost fabrication of electronics. Specifically, the contact printing approach shows great potential for realizing high-performance electronics with aligned quasi-1D materials. Despite being known for more than a decade, reports on a precisely controlled system to carry out...

Single-crystalline inorganic semiconducting nanowires (NWs) of technologically important materials such as Si, Ge, GaAs, ZnO and so on. have attracted significant attention in providing sustainable energy solutions (generation/storage) due to their attractive physical and chemical properties. Currently, the production processes of these devices is...

[This corrects the article DOI: 10.1038/s41378-021-00314-6.].

Printed devices on flexible and disposable substrates are receiving considerable interest for the realization of low-cost electronic and sensing systems. As a result, new methods such as resource-efficient printing and multimaterial additive manufacturing have been explored to develop a wide range of easily deployable systems such as displays, sens...

With rapid advances in the field of autonomous vehicles (AVs), the ways in which human–vehicle interaction (HVI) will take place inside the vehicle have attracted major interest and, as a result, intelligent interiors are being explored to improve the user experience, acceptance, and trust. This is also fueled by parallel research in areas such as...

The increasing number of devices needed by wearable systems to bring radical advances in healthcare, robotics, and human–machine interfaces is a threat to their growth if the integration and energy-related challenges are not managed. A natural solution is to reduce the number of devices while retaining the functionality or simply using multifunctio...

Multimaterial 3D printing in electronics is expanding due to the ability to realize geometrically complex systems with simplified processes compared with conventional printed circuit board. Herein, the feasibility of using a copper-based filament to realize 3D circuits with planar and vertical interconnections is presented. The resistivity of the t...

Wearable human machine interfaces (HMI) such as smart gloves have attracted considerable interest in recent years. The quality of the interactive experience with the real and virtual world using wearable HMI technologies depends on the intuitive two-way haptic interfaces they offer and the real-time touch-based information they send and receive. He...

Wearable UV photodetectors (PDs) have attracted interest recently for detection of excess exposure of the skin to the UV radiation. Despite numerous advances made in this direction, many challenges remain, particularly in terms of device reliability under extreme mechanical deformations simultaneously and self-powering, etc. Herein, a self-powered...

The continuous operation of wearable electronics demands reliable sources of energy, currently met through Li‐ion batteries and various energy harvesters. These solutions are being used out of necessity despite potential safety issues and unsustainable environmental impact. Safe and sustainable energy sources can boost the use of wearables systems...

The ability to display virtual objects midair that can be seen without special headwear is an attractive proposition for the virtual reality systems of the near future. Volumetric display technologies have demonstrated this concept, allowing users to view virtual objects with real dimensions in 3D space while enabling some forms of interaction. Dev...

Stimulus-responsive soft structures, with biological organs like intrinsic sensing, are needed to enable controlled movements and hence bring the transformative advances in soft robotics. Herein, bioinspired inchworm- and earthworm-like soft structures with intrinsic strain sensing achieved by seamless embedding of a graphite-paste-based sensor mat...

With rapid advances in the field of autonomous vehicles (AVs), the ways in which human-vehicle interaction (HVI) will take place inside the vehicle has attracted major interest and, as a result, intelligent interiors are being explored to improve the user experience, acceptance, and trust. This is also fueled by parallel research in areas such as p...

This paper presents a smart sensor patch with flexible strain sensor and a printed temperature sensor integrated with a Near Field Communication (NFC) tag to detect strain or temperature in a semi-quantitative way. The strain sensor is fabricated using conductive polymer poly (3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) in a polym...