Optimal trajectory generation for time-to-contact based aerial robotic perching
Many biological organisms (e.g. insects, birds, and mammals) rely on the perception of an
informational variable called time-to-contact (TTC) to control their motion for various tasks such
as avoiding obstacles, landing, or interception. TTC, defined as the required time to contact an
object if the current velocity is maintained, has been recently leveraged for robot motion control
in various tasks. However, most existing robotic applications of TTC simply control the TTC to be
constant or constantly decreasing, without fully exploring the applicability for TTC. In this paper,
we propose two-stage TTC based strategie...
Source: Bioinspiration and Biomimetics - November 27, 2018 Category: Science Authors: Haijie Zhang, Bo Cheng and Jianguo Zhao Source Type: research
Training bioinspired sensors to classify flows
We consider the inverse problem of classifying flow patterns from local sensory measurements. This
problem is inspired by the ability of various aquatic organisms to respond to ambient flow signals,
and is relevant for translating these abilities to underwater robotic vehicles. In Colvert, Alsalman
and Kanso, B&B (2018), we trained neural networks to classify vortical flows by relying on a single
flow sensor that measures a ‘time history’ of the local vorticity. Here, we systematically
investigate the effects of distinct types of sensors on the accuracy of flow classification. We
consider four types of sensors â€...
Source: Bioinspiration and Biomimetics - November 27, 2018 Category: Science Authors: Mohamad Alsalman, Brendan Colvert and Eva Kanso Source Type: research
Mosquitoes modulate leg dynamics at takeoff to accommodate surface roughness
Insects perform takeoffs from a nearly unquantifiable number of surface permutations and many use
their legs to initiate upward movement prior to the onset of wingbeats, including the mosquito. In
this study we examine the unprovoked pre-takeoff mechanics of Aedes aegypti mosquitoes from two
surfaces of contrasting roughness, one with roughness similar to polished glass and the other
comparable to the human forearm. Using high-speed videography, we find mosquitos exhibit two
distinct leg actions prior to takeoff, the widely observed push and a previously undocumented
leg-strike, where one of the rearmost legs is rais...
Source: Bioinspiration and Biomimetics - November 27, 2018 Category: Science Authors: Nicholas M Smith, Grace V Clayton, Hiba A Khan and Andrew K Dickerson Source Type: research
From healing wounds to resorbable electronics, levan can fill bioadhesive roles in scores of markets
Levan is a fructose homopolysaccharide which gained attention recently for its unusual combination
of properties distinguishing it from other natural biodegradable polysaccharides like chitosan,
cellulose or starch. Among the strongest bioadhesives, film-forming levan is garnering interest for
its role in some simple solutions to difficult problems. One of these is illustrated by the elegant
research using laser-based techniques to construct levan films for healing wounds and burned tissue.
Another is the development of bioresorbable electronic implants. Levan has been found in habitats as
diverse as salterns and the...
Source: Bioinspiration and Biomimetics - November 20, 2018 Category: Science Authors: Joan Combie and Ebru Toksoy Öner Source Type: research
Luminescence light collection technology in the aragonite of stone corals
Stone corals do not use calcium carbonate in the form of calcite, which has a calculated energy gap
of 3.93  eV, but in the form of aragonite, which has a calculated energy gap of 2.88 eV (here
experimentally determined to amount to 2.46  eV) as a building material. This enables the coral to
harvest blue light, which is penetrating and filtering deep into the surface water of the ocean.
White luminescence, which is composed of different wave lengths, is generated, and then conducted
and redistributed within the aragonite structure to be supplied to the symbiotic photosynthetic
algae. This mechanism of light con...
Source: Bioinspiration and Biomimetics - October 9, 2018 Category: Science Authors: N Neumann-Micheau and H Tributsch Source Type: research
Effect of toe joint stiffness and toe shape on walking biomechanics
During typical human walking, the metatarsophalangeal joints undergo extension/flexion, which we
term toe joint articulation. This toe joint articulation impacts locomotor performance, as evidenced
by prior studies on prostheses, footwear, sports and humanoid robots. However, a knowledge gap
exists in our understanding of how individual toe properties (e.g. shape, joint stiffness) affect
bipedal locomotion. To address this gap, we designed and built a pair of adjustable foot prostheses
that enabled us to independently vary different toe properties, across a broad range of
physiological and non-physiological values. W...
Source: Bioinspiration and Biomimetics - October 9, 2018 Category: Science Authors: Eric C Honert, Gerasimos Bastas and Karl E Zelik Source Type: research
Control of a muscle-like soft actuator via a bioinspired approach
Soft actuators have played an indispensable role in generating compliant motions of soft robots.
Among the various soft actuators explored for soft robotic applications, dielectric elastomer
actuators (DEAs) have caught the eye with their intriguing attributes similar to biological muscles.
However, the control challenge of DEAs due to their strong nonlinear behaviors has hindered the
development of DEA-based soft robots. To overcome the control challenge, this paper proposes a
bioinspired control approach of DEAs. A three-dimensional muscle-like DEA, capable of large forces
and giant deformation, is fabricated and a...
Source: Bioinspiration and Biomimetics - October 8, 2018 Category: Science Authors: Jiawei Cao, Wenyu Liang, Jian Zhu and Qinyuan Ren Source Type: research
Critical roughness in animal hairy adhesive pads: a numerical modeling approach
General understanding of adhesion failure of setal attachment pads at some particular substrate
roughness is important for construction of biologically active adhesive and anti-adhesive surfaces.
Here we present a numerical model which is capable of explaining experimentally found effects of the
adhesion drop on the level of an individual adhesive spatula. The model incorporates the interaction
of an elastic spatula with a rough substrate in 2D. The contact area and the work of adhesion have
been determined for two different types of the model substrates. The surfaces were either composed
of particles of different si...
Source: Bioinspiration and Biomimetics - September 20, 2018 Category: Science Authors: Alexander Kovalev, Alexander E Filippov and Stanislav N Gorb Source Type: research
Thrust force characterization of free-swimming soft robotic jellyfish
Five unique soft robotic jellyfish were manufactured with eight pneumatic network tentacle actuators
extending radially from their centers. These jellyfish robots were able to freely swim untethered in
the ocean, to steer from side to side, and to swim through orifices more narrow than the nominal
diameter of the jellyfish. Each of the five jellyfish robots were manufactured with a different
composition of body and tentacle actuator Shore hardness. A three-factor study was performed with
these five jellyfish robots to determine the impact that actuator material Shore hardness, actuation
frequency, and tentacle stroke...
Source: Bioinspiration and Biomimetics - September 17, 2018 Category: Science Authors: Jennifer Frame, Nick Lopez, Oscar Curet and Erik D Engeberg Source Type: research
A bio-inspired model for bidirectional polarisation detection
This study investigated a novel polarisation detection model based on the microstructure of rhabdom
in mantis shrimp eyes, in which a single unit can detect two directions of orthogonal polarisation.
The bionic model incorporated multi-layered orthogonal Si wire grids, and the finite-difference
time-domain method was used to simulate light absorption. A single-layer Si wire grid was simulated
to study the effects of thickness and duty cycle on extinction ratios. A multi-layer orthogonal wire
grid was simulated to study the effects of distance between adjacent layers. The simulations
revealed that the bionic model can...
Source: Bioinspiration and Biomimetics - September 13, 2018 Category: Science Authors: Qifan Zhu, Yuegang Fu and Zhiying Liu Source Type: research
Wing –wake interaction: comparison of 2D and 3D flapping wings in hover flight
The wing –wake interaction of flapping wings while hovering has been investigated, with the focus on
the difference in wing –wake interaction between 2D and 3D flapping wings. Numerical simulations are
conducted at a Reynolds number of 100, and the flapping configurations are divided into the 2D,
quasi-3D and 3D categories. Variations of the aspect ratio and Rossby number allow the flapping
configuration to morph gradually between categories. The wing –wake interaction mechanisms are
identified and the effect of three-dimensionality on these mechanisms is discussed.
Three-dimensionality affects wing –wake int...
Source: Bioinspiration and Biomimetics - September 13, 2018 Category: Science Authors: Y J Lee and K B Lua Source Type: research
Effect of shear stress on the reduction of bacterial adhesion to antifouling polymers
In this work, two antifouling polymer brushes were tested at different shear stress conditions to
evaluate their performance in reducing the initial adhesion of Escherichia coli . Assays were
performed using a parallel plate flow chamber and a shear stress range between 0.005 and 0.056 Pa.
These shear stress values are found in different locations in the human body where biomedical
devices are placed. The poly(MeOEGMA) and poly(HPMA) brushes were characterized and it was shown
that they can reduce initial adhesion up to 90% when compared to glass. Importantly, the performance
of these surfaces was not affected by the...
Source: Bioinspiration and Biomimetics - September 13, 2018 Category: Science Authors: Betina Lopez-Mila, Patr Ãcia Alves, Tomáš Riedel, Barbara Dittrich, Filipe Mergulhão and Cesar Rodriguez-Emmenegger Source Type: research
Walking with perturbations: a guide for biped humans and robots
This paper provides an update on the neural control of bipedal walking in relation to bioinspired
models and robots. It is argued that most current models or robots are based on the construct of a
symmetrical central pattern generator (CPG). However, new evidence suggests that CPG functioning is
basically asymmetrical with its flexor half linked more tightly to the rhythm generator. The
stability of bipedal gait, which is an important problem for robots and biological systems, is also
addressed. While it is not possible to determine how biological biped systems guarantee stability,
robot solutions can be useful to pr...
Source: Bioinspiration and Biomimetics - September 3, 2018 Category: Science Authors: Jacques Duysens and Arturo Forner-Cordero Source Type: research
Bio-inspired upper limb soft exoskeleton to reduce stroke-induced complications
Stroke has become the leading cause of disability and the second-leading cause of mortality
worldwide. Dyskinesia complications are the major reason of these high death and disability rates.
As a tool for rapid motion function recovery in stroke patients, exoskeleton robots can reduce
complications and thereby decrease stroke mortality rates. However, existing exoskeleton robots
interfere with the wearer ’s natural motion and damage joints and muscles due to poor human-machine
coupling. In this paper, a novel ergonomic soft bionic exoskeleton robot with 7  degrees of freedom
was proposed to address these problems...
Source: Bioinspiration and Biomimetics - August 23, 2018 Category: Science Authors: Ning Li, Tie Yang, Peng Yu, Junling Chang, Liang Zhao, Xingang Zhao, Imad H Elhajj, Ning Xi and Lianqing Liu Source Type: research
Corrigendum: An analytical model and scaling of chordwise flexible flapping wings in forward flight
(2016 Bioinspir. Biomim . 12 [http://doi.org/10.1088/1748-3190/12/1/016006] 016006
[http://doi.org/10.1088/1748-3190/12/1/016006] )
Description unavailable (Source: Bioinspiration and Biomimetics)
Source: Bioinspiration and Biomimetics - August 20, 2018 Category: Science Authors: Deepa Kodali and Chang-Kwon Kang Source Type: research
