A surface cleaning apparatus comprises a body including a rear compartment, a forward compartment and an intermediate compartment arranged between the rear and forward compartments. An elongate rotatable brush arrangement is positioned within and extends across the forward compartment. An electric motor is positioned in the rear compartment, and drive means extends between the rotatable brush arrangement and the electric motor.

Surface cleaning apparatus

Soft robotics and its related technologies enable robot abilities in several robotics domains including, but not exclusively related to, manipulation, manufacturing, human–robot interaction and locomotion. Although field applications have emerged for soft manipulation and human–robot interaction, mobile soft robots appear to remain in the research stage, involving the somehow conflictual goals of having a deformable body and exerting forces on the environment to achieve locomotion. This paper aims to provide a reference guide for researchers approaching mobile soft robotics, to describe the underlying principles of soft robot locomotion with its pros and cons, and to envisage applications and further developments for mobile soft robotics.

https://royalsocietypublishing.org/doi/pdf/10.1098/rsif.2017.0101

Fundamentals of soft robot locomotion.

A review of modelling and analysis of morphing wings

Butterflies display extreme variation in wing shape associated with tremendous ecological diversity. Disentangling the role of neutral versus adaptive processes in wing shape diversification remains a challenge for evolutionary biologists. Ascertaining how natural selection influences wing shape evolution requires both functional studies linking morphology to flight performance, and ecological investigations linking performance in the wild with fitness. However, direct links between morphological variation and fitness have rarely been established. The functional morphology of butterfly flight has been investigated but selective forces acting on flight behaviour and associated wing shape have received less attention. Here, we attempt to estimate the ecological relevance of morpho-functional links established through biomechanical studies in order to understand the evolution of butterfly wing morphology. We survey the evidence for natural and sexual selection driving wing shape evolution in butterflies, and discuss how our functional knowledge may allow identification of the selective forces involved, at both the macro- and micro-evolutionary scales. Our review shows that although correlations between wing shape variation and ecological factors have been established at the macro-evolutionary level, the underlying selective pressures often remain unclear. We identify the need to investigate flight behaviour in relevant ecological contexts to detect variation in fitness-related traits. Identifying the selective regime then should guide experimental studies towards the relevant estimates of flight performance. Habitat, predators and sex-specific behaviours are likely to be major selective forces acting on wing shape evolution in butterflies. Some striking cases of morphological divergence driven by contrasting ecology involve both wing and body morphology, indicating that their interactions should be included in future studies investigating co-evolution between morphology and flight behaviour.

/pdf/adaptive-evolution-of-butterfly-wing-shape-from-morphology-386cai5e3q.pdf

Adaptive evolution of butterfly wing shape: from morphology to behaviour

Owls are an order of birds of prey that are known for the development of a silent flight. We review here the morphological adaptations of owls leading to silent flight and discuss also aerodynamic properties of owl wings. We start with early observations (until 2005), and then turn to recent advances. The large wings of these birds, resulting in low wing loading and a low aspect ratio, contribute to noise reduction by allowing slow flight. The serrations on the leading edge of the wing and the velvet-like surface have an effect on noise reduction and also lead to an improvement of aerodynamic performance. The fringes at the inner feather vanes reduce noise by gliding into the grooves at the lower wing surface that are formed by barb shafts. The fringed trailing edge of the wing has been shown to reduce trailing edge noise. These adaptations to silent flight have been an inspiration for biologists and engineers for the development of devices with reduced noise production. Today several biomimetic applications such as a serrated pantograph or a fringed ventilator are available. Finally, we discuss unresolved questions and possible future directions.

https://royalsocietypublishing.org/doi/pdf/10.1098/rsfs.2016.0078

Features of owl wings that promote silent flight.

Aerial robots capable of locomotion in both air and water would enable novel mission profiles in complex environments, such as water sampling after floods or underwater structural inspections. The design of such a vehicle is challenging because it implies significant propulsive and structural design trade-offs for operation in both fluids. In this paper, we present a unique Aquatic Micro Air Vehicle (AquaMAV), which uses a reconfigurable wing to dive into the water from flight, inspired by the plunge diving strategy of water diving birds in the family Sulidae. The vehicle's performance is investigated in wind and water tunnel experiments, from which we develop a planar trajectory model. This model is used to predict the dive behaviour of the AquaMAV, and investigate the efficacy of passive dives initiated by wing folding as a means of water entry. The paper also includes first field tests of the AquaMAV prototype where the folding wings are used to initiate a plunge dive.

https://royalsocietypublishing.org/doi/pdf/10.1098/rsfs.2016.0085

Wind and water tunnel testing of a morphing aquatic micro air vehicle.

Many insects are well adapted to long-distance migration despite the larger energetic costs of flight for small body sizes. To optimize wing design for next-generation flying micro-robots, we analyse butterfly wing shapes and wing orientations at full scale using numerical simulations and in a low-speed wind tunnel at 2, 3.5 and 5 m s−1. The results indicate that wing orientations which maximize wing span lead to the highest glide performance, with lift to drag ratios up to 6.28, while spreading the fore-wings forward can increase the maximum lift produced and thus improve versatility. We discuss the implications for flying micro-robots and how the results assist in understanding the behaviour of the butterfly species tested.

https://royalsocietypublishing.org/doi/pdf/10.1098/rsfs.2016.0087

Aerodynamic evaluation of wing shape and wing orientation in four butterfly species using numerical simulations and a low-speed wind tunnel, and its implications for the design of flying micro-robots.

Despite significant research progress on small-scale aerial–aquatic robots, most existing prototypes are still constrained by short operation times and limited performance in different fluids. The main challenge is to design a vehicle that satisfies the partially conflicting design requirements for aerial and aquatic operations. In this letter we present a new class of aerial–aquatic robot, the sailing micro air vehicle, “SailMAV.” Thanks to a three-part folding wing design, the SailMAV is capable of both flying and sailing. The robot design permits long and targeted missions at the water interface by leveraging the wind as movement vector. It simultaneously offers the flexibility of flight for rapidly reaching a designated area, overcoming obstacles, and moving from one body of water to another, which can be very useful for water sampling in areas with many obstacles. With a total wingspan of 0.96 m, the SailMAV employs the same wing and actuation surfaces for sailing as for flying. It is capable of water surface locomotion as well as takeoff and flight at a cruising speed of 10.8 m
 $\cdot$ 
s
 $^{-1}$ 
. The main contributions of this letter are new solutions to the challenges of combined aerial and aquatic locomotions, the design of a novel hybrid concept, the development of the required control laws, and the demonstration of the vehicle successfully sailing and taking off from the water. This letter can inform the design of hybrid vehicles that adapt their morphology to move effectively.

/pdf/sailmav-design-and-implementation-of-a-novel-multi-modal-ir04dwngrf.pdf

SailMAV: Design and Implementation of a Novel Multi-Modal Flying Sailing Robot

A vacuum cleaner having a vac-motor and a dust separator for separating out dust particles entrained in an airflow drawn through the separator by the vac-motor. The separator is a multi-stage separator incorporating a cyclonic primary separation stage, a non-cyclonic secondary separation stage which is downstream of the primary separation stage and a cyclonic tertiary stage which is downstream of the secondary stage. In accordance with the invention, the secondary stage includes a flow bend for changing the direction of the airflow thereby to separate out dust particles entrained in the airflow. The vacuum cleaner also includes a primary dust collector for collecting dust particles separated out by the primary separation stage, a secondary dust collector for collecting the dust particles separated out by the flow bend and a tertiary dust collector for collecting dust separated out by the tertiary separation stage.

Separating apparatus in a vacuum cleaner

Aerial–aquatic robotic vehicles show great potential in assisting in disaster response and environmental monitoring. However, to undertake these missions, they need to overcome the challenges of power requirements for takeoff and the difficulty of transitioning reliably between the air and water media. The use of superhydrophobic surfaces offers solutions to these challenges by reducing the wetted surface area of such robotic vehicles. In this article, a range of superhydrophobic surfaces is analyzed for wettability and robustness performance to ascertain their benefits as a design feature for drag reduction in aerial–aquatic robotic vehicles. The silicon dioxide nanoparticle spray coating show the most superhydrophobicity measuring a static water contact angle of 174.8°. The coating's robustness tests yield a similar performance to that of laser‐engraved brass with 200 μm groove separation, displaying a contact angle of 133.0° after ten finger strokes. The silicon dioxide nanoparticle spray is then used for drag reduction testing due to its ease of coating complex 3D geometries among the techniques explored in this study. The spray is applied to the hull of a sailing–flying robot, which resulted in the robot's drag reduction averaging 40% in the hydroplaning regime.

/pdf/use-of-superhydrophobic-surfaces-for-performance-enhancement-3cbengyk.pdf

Alejandro Ortega Ancel

Papers

Wind and water tunnel testing of a morphing aquatic micro air vehicle.

Aerodynamic evaluation of wing shape and wing orientation in four butterfly species using numerical simulations and a low-speed wind tunnel, and its implications for the design of flying micro-robots.

SailMAV: Design and Implementation of a Novel Multi-Modal Flying Sailing Robot

Separating apparatus in a vacuum cleaner

Use of Superhydrophobic Surfaces for Performance Enhancement of Aerial–Aquatic Vehicles