A Novel Concept for the Study of Heterogeneous Robotic Swarms warm robotics systems are characterized by decentralized control, limited communication between robots, use of local information, and emergence of global behavior. Such systems have shown their potential for flexibility and robustness [1]-[3]. However, existing swarm robotics systems are by and large still limited to displaying simple proof-of-concept behaviors under laboratory conditions. It is our contention that one of the factors holding back swarm robotics research is the almost universal insistence on homogeneous system components. We believe that swarm robotics designers must embrace heterogeneity if they ever want swarm robotics systems to approach the complexity required of real-world systems. To date, swarm robotics systems have almost exclusively comprised physically and behaviorally undifferentiated agents. This design decision has its roots in ethological models of self-organizing natural systems. These models serve as inspiration for swarm robotics system designers, but are often highly abstract simplifications of natural systems and, to date, have largely assumed homogeneous agents. Selected dynamics of the systems under study are shown to emerge from the interactions of identical system components, ignoring the heterogeneities (physical, spatial, functional, and informational) that one can find in almost any natural system. The field of swarm robotics currently lacks methods and tools with which to study and leverage the heterogeneity that is present in natural systems. To remedy this deficiency, we propose swarmanoid, an innovative swarm robotics system composed of three different robot types with complementary skills: foot-bots are small autonomous robots specialized in moving on both even and uneven terrains, capable of self-assembling and of transporting objects or other robots; hand-bots are autonomous robots capable of climbing some vertical surfaces and manipulating small objects; and eye-bots are autonomous flying robots that can attach to an indoor ceiling, capable of analyzing the environment from a privileged position to S

Clear, vitreous films of boron nitride up to 6000Aå thick have been deposited on a variety of substrates at 600 °–1000 °C by a reaction between diborane and ammonia in hydrogen or inert carrier gas. Deposition rate may be readily adjusted to 50–1000 Aå/min. Most samples were made at either 600° or 800°, with some attendant variation in film properties. The 600° material contains some residual B‐H bonding. The film is essentially amorphous to electron diffraction. The refractive index is 1.7–1.8, the 1 MHz dielectric constant ∼ 3 1/2, the dielectric strength ∼5×106 normalv/normalcm , and the 25°Cnormalresistivity≥1014 normalohm‐normalcm The band gap is 3.8 ev and the phonon temperature in the neighborhood of 2000°K. For semiconductor junction protection boron nitride has no advantage over silicon nitride. 600° deposition directly on Si has produced surface charges as low as 4×l011/cm2 , but there are room‐temperature drifts, and high‐field conduction also. BN deposited at 800° on Si is electrically similar to silicon nitride. Etching of BN film also presents the same problems as does silicon nitride. BN is not as good a barrier against sodium ion permeation. Attack by atmospheric moisture over a long period has varied from insignificant to extensive conversion to orthoboric acid.BN film on Si dopes the substrate with boron at temperatures above 900 °C in inert ambient. Uniform junction depths are produced. D‐C conductivity in 500–4000Aå films has been studied from room temperature to 270 °C. With fields ≥ 106 v/cm BN film shows stable, nonohmic conductivity which is independent of polarity. The 25 °C d‐c conduction is describable over at least seven decades of current by J∝En , normaln=13–15 , where J=normalcurrent density , E=normalfield strength . The 600°‐deposited BN is the more conductive and can carry 0.1 normalamp/cm2 indefinitely. normalLogJnormalvs.E1/2 normalat 25° is linear, and the slope of the curve is in good agreement with the theoretical value for a Frenkel‐Poole conduction mechanism. Possible use of BN as a thin film varistor is discussed.

Abstract-Flying has an advantage when compared to ground based locomotion, as it simplifies the task of overcoming obstacles and allows for rapid coverage of an area while also providing a birds-eye-view of the environment. One of the key challenges that has prevented engineers from coming up with convincing aerial solutions for indoor exploration is the energetic cost of flying. This paper presents a way of mitigating the energy problem regarding aerial exploration within indoor environments. This is achieved by means of a model to estimate the endurance of a hover-capable flying robot and by using ceiling attachment as a means of preserving energy while maintaining a birds-eye-view. The proposed model for endurance estimation has been extensively tested using a custom-developed quadrotor and autonomous ceiling attachment system. I. CHALLENGES AND STATE OF THE ARTThe idea of using flying robots to explore indoor environments has become popular within the robotic community in recent times1 2 . Flying has an advantage when compared to ground based locomotion, as it simplifies the task of overcoming obstacles and allows for rapid coverage of an area while also providing a birds-eyeview of the environment. One of the key challenges that has prevented engineers from coming up with convincing aerial solutions for indoor exploration is the energetic cost of flying, which is orders of magnitude higher than that of terrestrial locomotion.Imagine a robot that can fly around indoors, its task is to search a building for a pre-defined target, for example an injured human. It flies into a room and uses its onboard thermal vision sensors to scan the room for the injured human. After finding no positive matches the robot flies into the next room. The robot searches three rooms in this manner and locates the injured human in the last room. The robot has a limited amount of energy. If the robot was required to search more than these three rooms, then it is likely that its limit is reached before finding its target. If the robot could attach to the ceiling while it is searching the room, instead of remaining airborne, the search could be extended from minutes to hours, which could make all the difference in such a situation.Valenti and collaborators have developed a health management system to aid online mission planning for swarms of hovering Unmanned Air Vehicles (UAV) [6]. They have found that it is possible to estimate the remaining flight endurance by comparing the platforms battery voltage and This paper tackles the energy problem of aerial exploration within indoor environments, first by using ceiling attachment as a means for preserving energy, while still maintaining the birds-eye-view and second by providing an estimation model to estimate the endurance of a hover-capable flying robot. The proposed model for endurance estimation has been extensively tested using a custom-developed quadrotor and ceiling attachment system (Fig. 1). The ceiling attachment feature has been successfully demonstrated by autonomously flying ...

Abstract-In the growing field of collective robotics, spatial co-ordination between robots is often critical and usually achieved via local relative positioning sensors. We believe that range and bearing sensing, based on infrared technology, has the potential to fulfil the strict requirements of real-world collective robots. These requirements include: small size, light weight, large range, high refresh rate, immunity against tilting and misalignment, immunity against ambient light changes, and good range and bearing accuracy. Currently, there are no range and bearing systems that have been designed to cope with such strict requirements. This paper presents a custom range and bearing system, based on a novel cascaded filtering technology, complemented by hybrid infrared/Radio Frequency (RF) communication, which has been designed specifically to meet all these expectations. The system has been characterised and tested, proving its viability.

Silicon oxynitride films from the NO‐NH3‐SiH4 reaction in nitrogen at 850°C are clear, adherent, amorphous dielectrics whose composition may be varied over the entire range between SiO2 and Si3N4 by controlling the NH3/NO ratio employed. The refractive index is a convenient and accurate measure of the composition. Over much of the nitrogen‐rich range, the Si content is about 2% ower than stoichiometric, and the hypothesis is made that one nitrogen in three is bonded to only two other skeletal atoms instead of three, and that some of these nitrogens bear bonded hydrogen. The N‒H groups are believed to play a role similar to that of O‒H in silicas. Compositions near Si2ON2 are highly resistant to ionizing radiation under bias, and are excellent Na+ barriers at 300°C and 106 V/cm. However, they are not better barriers to Na+ thermal diffusion at 600°C than SiO2 . With appropriate pre‐ and post‐deposition chemical treatments, oxynitride films give low Si surface charge and small nonionicshifts in flatband voltage with bias‐temperature aging. Other properties investigated for various compositions include etch rate, i.r. spectrum, film stress,and cathodoluminescence spectra. Films from the NO‐SiH4 and NO‐NH3‐SiH4 processes are compared.

Swarms of indoor flying robots are promising for many applications, including searching tasks in collapsing buildings, or mobile surveillance and monitoring tasks in complex man-made structures. For tasks that employ several flying robots, spatial-coordination between robots is essential for achieving collective operation. However, there is a lack of on-board sensors capable of sensing the highlydynamic 3-D trajectories required for spatial-coordination of small indoor flying robots. Existing sensing methods typically utilise complex SLAM based approaches, or absolute positioning obtained from off-board tracking sensors, which is not practical for real-world operation. This paper presents an adaptable, embedded infrared based 3-D relative positioning sensor that also operates as a proximity sensor, which is designed to enable inter-robot spatial-coordination and goal-directed flight. This practical approach is robust to varying indoor environmental illumination conditions and is computationally simple.Keywords Relative positioning sensing · Indoor flying robots · Collective operation · 3D sensor · Spatial-coordination · Proximity sensing J.F.R. developed the concept of relative positioning sensing for enabling goal-directed flight on indoor collective flying robots, wrote the manuscript, developed the sensor hardware/firmware, developed the calibration tools and characterised the sensor. T.S. extensively contributed to the sensor firmware and characterisation. J.-C.Z. and D.F. conceived and directed the project sponsoring the work described in the article. They also provided continue support and feedback towards reaching the attained results.

Abstract-Swarms of flying robots are promising in many applications due to rapid terrain coverage. However, there are numerous challenges in realising autonomous operation in unknown indoor environments. A new autonomous flight methodology is presented using relative positioning sensors in reference to nearby static robots. The entirely decentralised approach relies solely on local sensing without requiring absolute positioning, environment maps, powerful computation or longrange communication. The swarm deploys as a robotic network facilitating navigation and goal directed flight. Initial validation tests with quadrotors demonstrated autonomous flight within a confined indoor environment, indicating that they could traverse a large network of static robots across expansive environments.

When thin-film platinum and single-crystal silicon are interdiffused, [inverted lazy s] 100 Å of SiO2 is found at the PtSi surface. The silica protects the silicide from attack by the aqua regia commonly used to remove unreacted Pt. If the silica is stripped, PtSi on Si will dissolve in aqua regia even faster than Pt. These findings are applicable to contact technology for silicon devices and integrated circuits.