This article presents a new algorithm for searching odour sources across large search spaces with groups of mobile robots. The proposed algorithm is inspired in the particle swarm optimization (PSO) method. In this method, the search space is sampled by dynamic particles that use their knowledge about the previous sampled space and share this knowledge with other neighbour searching particles allowing the emergence of efficient local searching behaviours. In this case, chemical searching cues about the potential existence of upwind odour sources are exchanged. By default, the agents tend to avoid each other, leading to the emergence of exploration behaviours when no chemical cue exists in the neighbourhood. This behaviour improves the global searching performance.The article explains the relevance of searching odour sources with autonomous agents and identifies the main difficulties for solving this problem. A major difficulty is related with the chaotic nature of the odour transport in the atmosphere due to turbulent phenomena. The characteristics of this problem are described in detail and a simulation framework for testing and analysing different odour searching algorithms was constructed. The proposed PSO-based searching algorithm and modified versions of gradient-based searching and biased random walk-based searching strategies were tested in different environmental conditions and

Integration of solid-state microchips into soft-matter, and stretchable printed electronics has been the biggest challenge against their scalable fabrication. We introduce, Pol-Gel, a simple technique for self-soldering, self-encapsulation, and self-healing, that allows low cost, scalable, and rapid fabrication of hybrid microchip-integrated ultra-stretchable circuits. After digitally printing the circuit, and placing the microchips, we trigger a Polymer-Gel transition in physically cross-linked block copolymers substrate, and silver liquid metal composite ink, by exposing the circuits to the solvent vapor. Once in the gel state, microchips penetrate to the ink and the substrate (Self-Soldering), and the ink penetrates to the substrate (Self-encapsulation). Maximum strain tolerance of ~1200% for printed stretchable traces, and >500% for chip-integrated soft circuits is achieved, which is 5x higher than the previous works. We demonstrate condensed soft-matter patches and e-textiles with integrated sensors, processors, and wireless communication, and repairing of a fully cut circuits through Pol-Gel.

E‐waste is rapidly turning into another man‐made disaster. It is proposed that a paradigm shift toward a more sustainable future can be made through soft‐matter electronics that are resilient, repairable if damaged, and recyclable (3R), provided that they achieve the same level of maturity as industrial electronics. This includes high‐resolution patterning, multilayer implementation, microchip integration, and automated fabrication. Herein, a novel architecture of materials and methods for microchip‐integrated condensed soft‐matter 3R electronics is demonstrated. The 3R function is enabled by a biphasic liquid metal‐based composite, a block copolymer with nonpermanent physical crosslinks, and an electrochemical technique for material recycling. In addition, an autonomous laser‐patterning method for scalable circuit patterning with an exceptional resolution of <30 µm in seconds is developed. The phase‐shifting property of the BCPs is utilized for vapor‐assisted “soldering” circuit repairing and recycling. The process is performed entirely at room temperature, thereby opening the door for a wide range of heat‐sensitive and biodegradable polymers for the next generation of green electronics. The implementation and recycling of sophisticated skin‐mounted patches with embedded sensors, electrodes, antennas, and microchips that build a digital fingerprint of the human electrophysiological signals is demonstrated by collecting mechanical, electrical, optical, and thermal data from the epidermis.

Autonomous search of odour sources is a problem that once solved can bring large improvements to tasks like: humnnitarian demining, airportpatmlling, and hazardous chemical leaks detection. The main obstacles to the research in this area are the properties of current gas sensors (slow, weakly selective and poorly sensitive) and the dificulty to estimate the physical characteristics of natural odour plumes due to the "disturbances" caused by turbulence, namely meandering and intermittence. This paper presents an active olfactory sensing system that intends to be applicable to search for odour sources in outdoor environments. Three modular intelligent modules compose this olfactory system: two gas sensing nostrils and a directional ihermal anemometer The informntion coming from the sensing modules isfused with the spatio-temporal localization of a mobile mbot in order to estimate the localization of a specific odour source. The mobile robot is controlled by a state-based odour-searching algorithm. Each sensing module self-adjust its characteristics (sensibilify, selectivify and lime-response) in order to optimise the information perceived during each searching state. The paper describes the sensing modules and presents results gathered with them. A special emphasis is given to the wavelet-based signal processing, implemented for the fast identification of odour puffs.

Despite the rapid progress on soft and stretchable batteries, current fabrication techniques involve manual disposition and stencil/screen printing. Here, for the first time, a 3D-printed Ag-Ga battery is introduced through subsequent printing of four sinter-free composites: a stretchable Liquid Metal (LM) EGaIn-Ag-Styrene-isoprene block copolymers (SIS), and Carbon-SIS current collectors; Ag 2 O-SIS cathode; and a novel Ga-C-SIS anode. Being sinter-free results in faster printing, and compatibility with heat-sensitive substrates. Although the Ga-C-SIS is solid-like and nonsmearing after printing, it creates a liquid interface after contacting with the electrolyte. This results in a self-feeding and self-aggregation mechanism that brings more gallium to the surface and delays the formation of the dead surface. The recordbreaking areal capacity of ≈19.4 mAh cm −2 , along with excellent stretchability (>130% Max. strain), makes the Ag-Ga battery an excellent alternative to Ag-Zn batteries. Surprisingly, digital printing results in 3x higher areal capacity compared to stencil printing, due to greater gallium exposure at the surface. The desired voltage and current output can be customized by printing several battery cells and interconnect them in series/parallel. Also, printing of sensors, electrodes, batteries, and interconnects on a biomonitoring e-textile for simultaneous monitoring of electrocardiography, body temperature, and respiration is demonstrated.

This paper proposes an olfaction based methodology to automatically cover an unknown area enabling the decoupled cooperation of a group of floor cleaning mobile robots. This method is based on the utilisation of low cost chemical sensors in cleaning mobile robots, in order to differentiate clean from dirty areas. The experimental results show that the use of olfactory capabilities allows to efficiently cover and clean a certain area, and demonstrate the possibility of coordinating several mobile robots without the need of expensive sensing capabilities, map building or complex algorithms for task scheduling.

This paper describes a prototype of an inertial navigation system for use in mobile land vehicles, such as cars or mobile robots. The complete system is composed by sensors, their mechanical mount and cabling, these connect to a PC card with local processing and memory. based on a lniel 80Cl96KC micro-controller.The sensors used were a piezoelectric vibrating gyroscope, two silicon accelerometers, two clitionieters and ulso a magnetic flux-gate compass acting as uti independent sourcc for drvt compensation. The workinx principle of the vurious sensors are presented.The experimental setup used for testing is based on a robot ann controlled in real time to move the sensors along a known trajectory (velocity control).

This article is concerned with the simulation of pursuit. The article describes one solution for the problem of pursuit of objects moving on a plane by using a mobile robot and an active vision system. The solution deals with the interaction of different control systems using visual feedback and it is accomplished by the implementation of a visual gaze holding process interacting cooperatively with the control of the trajectory of a mobile robot. These two systems are integrated to follow a moving object at constant distance and orientation with respect to the mobile robot. The orientation and the position of the active vision system running a gaze holding process give the feedback signals to the control used to pursuit the target in real-time. The paper addresses the problems of visual fixation, visual smooth pursuit, navigation using visual feedback and compensation for system's movements. The algorithms for visual processing and control are described in the article. The mechanisms of cooperation between the different control and visual algorithms are also described. The final solution is a system able to operate at approximately human walking rates as the experimental results show at the end of the article.