Geckos are nature's elite climbers. Their remarkable climbing feats have been attributed to specialized feet with hairy toes that uncurl and peel in milliseconds. Here, we report the secret gecko's arboreal acrobatics includes an active tail. We examine tail's role during rapid climbing, aerial descent, gliding. show a tail functions as emergency fifth leg prevent falling climbing. A response initiated by slipping causes tip push against vertical surface, thereby preventing pitch-back of...

The state of a collection phase-locked oscillators is determined by single phase variable or cyclic coordinate. This paper presents computational method, Phaser, for estimating the from limited amounts multivariate data in presence noise and measurement errors. Measurements are assumed to be multidimensional time series. Each series consists several cycles same similar systems. within each system not identical. Using measurements covariance input, individual combined reduce variance...

In nature, cockroaches run rapidly over complex terrain such as leaf litter. These substrates are rarely rigid, and frequently very compliant. Whether how compliant surfaces change the dynamics of rapid insect locomotion has not been investigated to date largely due experimental limitations. We tested hypothesis that a running can maintain average forward speed an extremely soft elastic surface (10 N m(-1)) equal 2/3 its virtual leg stiffness (15 m(-1)). Cockroaches Blaberus discoidalis were...

Dynamic mode decomposition (DMD) is a powerful tool for extracting spatial and temporal patterns from multi-dimensional time series, it has been used successfully in wide range of fields, including fluid mechanics, robotics neuroscience. Two the main challenges remaining DMD research are noise sensitivity issues related to Krylov space closure when modelling nonlinear systems. Here, we investigate combination nonlinearity controlled setting, by studying class systems with linear latent...

Dynamical systems with asymptotically stable periodic orbits are generic models for rhythmic processes in dissipative physical systems. This paper presents a method reconstructing the dynamics near orbit from multivariate time-series data. It is used to test theories about control of legged locomotion, context which time series short when compared previous work nonlinear analysis. The presented here identifies appropriate dimensions reduced order deterministic portion dynamics. also...

We show that, near periodic orbits, a class of hybrid models can be reduced to or approximated by smooth continuous-time dynamical systems. Specifically, an exponentially stable orbit undergoing isolated transitions in system, nearby executions generically contract super constant-dimensional subsystem. Under non-degeneracy condition on the rank deficiency associated Poincaré map, contraction occurs finite time regardless stability properties orbit. Hybrid may removed from resulting subsystem...

Running is an essential mode of human locomotion, during which ballistic aerial phases alternate with when a single foot contacts the ground. The spring-loaded inverted pendulum (SLIP) provides starting point for modelling running, and generates ground reaction forces that resemble those centre mass (CoM) runner. Here, we show while SLIP reproduces within-step kinematics CoM in three dimensions, it fails to reproduce stability predict future motions. We construct control models using...

We studied the Thermal Performance Curves (TPCs) of 87 species rainforest ants and found support for both Adaptation Phosphorus-Tolerance hypotheses. TPCs relate a fitness proxy (here, worker speed) to environmental temperature. posits that thermal generalists (ants with flatter, broader TPCs) are favored in hotter, more variable tropical canopy compared cooler, less litter below. As predicted, nesting forest 1) had running speeds sensitive temperature; 2) ran over greater range...

Data-driven models of robot motion constructed using principles from Geometric Mechanics have been shown to produce useful predictions for a variety robots. For robots with number DoF, these geometric mechanics can only be in the neighborhood gait. Here we show how Gaussian Mixture Models (GMM) used as form manifold learning that learns structure "motility map" and demonstrate: [i] sizable improvement prediction quality when compared previously published methods; [ii] method applied any...

Legged animals utilize gait selection to move effectively and must re-cover from environmental perturbations. We show that on rough terrain domestic dogs, Canis lupus familiaris, spend more time in longitudinal quasi-statically stable patterns of movement. Here refers the rostro-caudal, axis. used an existing model literature quantify quasi-static stability gaits neighbouring walk, found trot-like are stable. thus hypothesized when perturbed, rate return a would depend direction...

We study a class of discontinuous vector fields brought to our attention by multilegged animal locomotion. Such arise not only in biomechanics, but also robotics, neuroscience, and electrical engineering, name few domains application. Under the conditions that (i) field's discontinuities are locally confined finite number smooth submanifolds (ii) field is transverse these surfaces an appropriate sense, it known yields well--defined flow Lipschitz continuous. extend results showing this...

We describe a mobile modular robot system that can generate foam to make structural elements. The platform itself is built of CKBot modules and carries extra along with generation device. demonstrate the synthesizing new morphologies: snake-like legged robot. also use structures encapsulate pick-up objects modify environment by blocking door. Our presentation describes issues arose in implementing using this technique.

We study global properties of the (center-)stable manifold a normally attracting invariant (NAIM), special case hyperbolic (NHIM) with empty unstable bundle. restrict our attention to continuous-time dynamical systems, or flows. show that stable foliation NAIM has structure topological disk bundle, and similar statements hold for inflowing NAIMs general compact NHIMs. Furthermore, Ck bundle if local is assumed Ck. then dynamics restricted are globally topologically conjugate linearized...

Home oxygen therapy (HOT) is a medical treatment for patients suffering from severe lung diseases. Although walking outdoors recommended to maintain physical strength, always have carry portable supplier which not sufficiently light weight this purpose. Our ultimate goal develop mobile robot an tank and follow patient in urban outdoor environment. We proposed with tether interface detect the relative position of foregoing patient. In paper, we improve platform mechanisms active wheels...

When the Poincaré map associated with a periodic orbit of hybrid dynamical system has constant-rank iterates, we demonstrate existence constant-dimensional invariant subsystem near which attracts all nearby trajectories in finite time. This result shows that long-term behavior model large number degrees-of-freedom may be governed by low-dimensional smooth system. The appearance such simplified models enables translation analytical tools from systems—such as Floquet theory—to setting and...

Legged movement is ubiquitous in nature and of increasing interest for robotics. Most legged animals routinely encounter foot slipping, yet detailed modeling multiple contacts with slipping exceeds current simulation capacity. Here we present a principle that unifies multilegged walking (including involving slipping) slithering Stokesian (low Reynolds number) swimming. We generated data-driven principally kinematic models locomotion low-slip (Argentine ant, 4.7% slip ratio to total motion)...

SUMMARY The fields of modular reconfigurable robotics and programmable matter study how to compose functionally useful systems from configurations modules. In addition the external shape a module configuration, internal arrangement modules bonds between them can greatly impact relevant mechanical properties such as load bearing ability. A fast method evaluate property aids search for an achieving desired space possible grows combinatorially. We present approximate where are represented with...

In this article, we present plate and reinforced flexure (PARF) fabrication, an inexpensive, rapid fabrication technique for robot mechanisms inspired by the smart composite manufacturing (SCM) used in VelociRoACH RoboBee designs. PARF extends SCM to larger sizes at low costs. We develop a meter-scale hexapedal robot, BigANT, design made publicly available. Manufacture of BigANT requires minimal tooling-foam board, tape, saw blade, knife; chassis costs <; US$20 materials, encouraging its use...