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In the paper, we are going to show how robotics is undergoing a shift in a bionic direction after a period of emphasis on artificial intelligence and increasing computational efficiency, which included isolation and extreme specialization. We assemble these new developments under the label of the morphological paradigm. The change in its paradigms and the development of alternatives to the principles that dominated robotics for a long time contains a more general epistemological significance. The role of body, material, environment, interaction and the paradigmatic status of biological and evolutionary systems for the principles of control are crucial here. Our focus will be on the introduction of the morphological paradigm in a new type of robotics and to contrast the interests behind this development with the interests shaping former models. The article aims to give a clear account of the changes in principles of orientation and control as well as concluding general observation in terms of historical epistemology, suggesting further political-epistemological analysis. [ABSTRACT FROM AUTHOR]

For robots to navigate successfully in the real world, unstructured environment adaptability is a prerequisite. Although this is typically implemented within the control layer, there have been recent proposals of adaptation through a morphing of the body. However, the successful demonstration of this approach has mostly been theoretical and in simulations thus far. In this work we present an underwater hopping robot that features a deformable body implemented as a deployable structure that is covered by a soft skin for which it is possible to manually change the body size without altering any other property (e.g. buoyancy or weight). For such a system, we show that it is possible to induce a stable hopping behavior instead of a fall, by just increasing the body size. We provide a mathematical model that describes the hopping behavior of the robot under the influence of shape-dependent underwater contributions (drag, buoyancy, and added mass) in order to analyze and compare the results obtained. Moreover, we show that for certain conditions, a stable hopping behavior can only be obtained through changing the morphology of the robot as the controller (i.e. actuator) would already be working at maximum capacity. The presented work demonstrates that, through the exploitation of shape-dependent forces, the dynamics of a system can be modified through altering the morphology of the body to induce a desirable behavior and, thus, a morphological change can be an effective alternative to the classic control. [ABSTRACT FROM AUTHOR]

Abstract Biological systems are outperforming machines in legged locomoting under almost any conditions. This is partly due to their capability of learning from failure and adapting their control approach and morphological features. This paper proposes an approach that extends the spring-loaded inverted pendulum (SLIP) model with the capability to adapt its attack angle (control) and stiffness (morphology) based on previous locomotion attempts. A set of different update rules, i.e., how this experience is used to adapt, are systematically investigated. The results suggest that modifying either attack angle, or stiffness, or both is beneficial with respect to achieve stable locomotion. Particularly, if the current system configuration (control and morphology) outperforms the previous one, the results suggest that increasing the angle and decreasing the stiffness of the system leads to more stable solutions. Consequently, the basic SLIP model extended by the proposed learning capabilities is able to reach stable locomotion over a much wider range of parameter combinations simply through trial and error. [ABSTRACT FROM AUTHOR]

An introduction to the journal is presented in which the editor discusses various reports within the issue on topics including formalization of the concept of morphological computation, the influence of morphology on locomotion, and the link of emotions with changes in morphology.

The generation of robust periodic movements of complex nonlinear robotic systems is inherently difficult, especially, if parts of the robots are compliant. It has previously been proposed that complex nonlinear features of a robot, similarly as in biological organisms, might possibly facilitate its control. This bold hypothesis, commonly referred to as morphological computation, has recently received some theoretical support by Hauser et al. (Biol Cybern 105:355-370, doi:, ). We show in this article that this theoretical support can be extended to cover not only the case of fading memory responses to external signals, but also the essential case of autonomous generation of adaptive periodic patterns, as, e.g., needed for locomotion. The theory predicts that feedback into the morphological computing system is necessary and sufficient for such tasks, for which a fading memory is insufficient. We demonstrate the viability of this theoretical analysis through computer simulations of complex nonlinear mass-spring systems that are trained to generate a large diversity of periodic movements by adapting the weights of a simple linear feedback device. Hence, the results of this article substantially enlarge the theoretically tractable application domain of morphological computation in robotics, and also provide new paradigms for understanding control principles of biological organisms. [ABSTRACT FROM AUTHOR]

The control of compliant robots is, due to their often nonlinear and complex dynamics, inherently difficult. The vision of morphological computation proposes to view these aspects not only as problems, but rather also as parts of the solution. Non-rigid body parts are not seen anymore as imperfect realizations of rigid body parts, but rather as potential computational resources. The applicability of this vision has already been demonstrated for a variety of complex robot control problems. Nevertheless, a theoretical basis for understanding the capabilities and limitations of morphological computation has been missing so far. We present a model for morphological computation with compliant bodies, where a precise mathematical characterization of the potential computational contribution of a complex physical body is feasible. The theory suggests that complexity and nonlinearity, typically unwanted properties of robots, are desired features in order to provide computational power. We demonstrate that simple generic models of physical bodies, based on mass-spring systems, can be used to implement complex nonlinear operators. By adding a simple readout (which is static and linear) to the morphology such devices are able to emulate complex mappings of input to output streams in continuous time. Hence, by outsourcing parts of the computation to the physical body, the difficult problem of learning to control a complex body, could be reduced to a simple and perspicuous learning task, which can not get stuck in local minima of an error function. [ABSTRACT FROM AUTHOR]

Despite many efforts, balance control of humanoid robots in the presence of unforeseen external or internal forces has remained an unsolved problem. The difficulty of this problem is a consequence of the high dimensionality of the action space of a humanoid robot, due to its large number of degrees of freedom (joints), and of non-linearities in its kinematic chains. Biped biological organisms face similar difficulties, but have nevertheless solved this problem. Experimental data reveal that many biological organisms reduce the high dimensionality of their action space by generating movements through linear superposition of a rather small number of stereotypical combinations of simultaneous movements of many joints, to which we refer as kinematic synergies in this paper. We show that by constructing two suitable non-linear kinematic synergies for the lower part of the body of a humanoid robot, balance control can in fact be reduced to a linear control problem, at least in the case of relatively slow movements. We demonstrate for a variety of tasks that the humanoid robot HOAP-2 acquires through this approach the capability to balance dynamically against unforeseen disturbances that may arise from external forces or from manipulating unknown loads. [ABSTRACT FROM AUTHOR]

Abstract: Echo state networks (ESNs) are a novel approach to recurrent neural network training with the advantage of a very simple and linear learning algorithm. It has been demonstrated that ESNs outperform other methods on a number of benchmark tasks. Although the approach is appealing, there are still some inherent limitations in the original formulation. Here we suggest two enhancements of this network model. First, the previously proposed idea of filters in neurons is extended to arbitrary infinite impulse response (IIR) filter neurons. This enables such networks to learn multiple attractors and signals at different timescales, which is especially important for modeling real-world time series. Second, a delay&sum readout is introduced, which adds trainable delays in the synaptic connections of output neurons and therefore vastly improves the memory capacity of echo state networks. It is shown in commonly used benchmark tasks and real-world examples, that this new structure is able to significantly outperform standard ESNs and other state-of-the-art models for nonlinear dynamical system modeling. [Copyright &y& Elsevier]

Presents the three-dimensional crystal structure of rabbit sterol carrier protein 2 determined at 1.8 A resolution. Alpha/beta fold; Five-stranded antiparallel beta-sheet flanked by five helices; C-terminal segment forming a hydrophobic tunnel; Similarity in the structure of sterol carrier protein 2 and nonspecific lipid transfer proteins.

Presents information on a study which showed that scavenger receptor class B type I is present in the small-intestine brush border membrane when it facilitates the uptake of dietary cholesterol from either bile salt micelles or phospholipid vesicles. Experimental procedures; Results; Discussion.

Mitochondrial aspartate aminotransferase was selectively labeled with various maleimide-linked nitroxide spin labels at the conformationally sensitive Cys166. The mobility of the spin group was found to increase with increasing length of the spacer between the nitroxide and maleimide moiety. The label with the ethylcarbamoyl group, a spacer of intermediate length, responded sensitively to conformational changes of aspartate aminotransferase. The modification with this label decreased the enzymic activity to 30% of its initial value and increased the affinity for various substrates and inhibitors 5-10-fold. Identical ESR spectra were obtained for the pyridoxal and pyridoxamine form of the enzyme. These spectra are complex, consisting of an isotropic and at least two anisotropic components. The spectral complexity is attributed to different modes of interaction of the spin label with its local protein environment giving rise to different motional states. The same changes in the ESR spectra have been observed upon formation of the adsorption complex of the pyridoxal form with a competitive inhibitor and on formation of covalent intermediates of the transamination reaction. Essentially, the isotropic component is converted to a new anisotropic one as the local environment changes due to a conformational adaptation of aspartate aminotransferase. The ESR data are consistent with an equilibrium between two conformational states of the enzyme but inconsistent with individual protein conformations of the various intermediates of the transamination reaction. The two contormational states may be assigned to the open and closed conformations as defined by X-ray crystallography. In the adsorption complex of the pyridoxal enzyme, and in the covalent intermediates, the two-state equilibrium appears to be shifted towards the closed conformation in which the spin label is more rigidly bound, as also suggested by molecular dynamic simulations of the label modelled into aspartate aminotransferase. In contrast the formation of adsorption complexes between the pyridoxamine form and aspartate or maleate was not accompanied by the same shift of the conformational equilibrium. [ABSTRACT FROM AUTHOR]

The binding of Ca2+ to monolayers and bilayers of phosphatidylserine has been investigated as a function of pH, ionic strength (NaCl concentration) and Ca2+ concentration using surface and colloid chemical techniques. The molar ratio of lipid to bound calcium decreases to 2 as the Ca2+ concentration is increased to about 0.1 mM. At [Ca2+] > 0.1 mM a 1:1 complex is formed. The apparent binding constant Ka ranges from about 106-104 l/mol depending on the Ca2+ concentration. After allowing for electrostatic effects and neighbour group interactions, the intrinsic binding constant Ki of the phosphorylserine polar group at pH 7 (I = 0.0I M), where it carries a net negative charge of one, is ≈ 104 l/mol; consistent values for Ki were obtained using several independent approaches. Ka for Ca2+ binding decreases with increasing NaCl concentration because the monovalent cations compete with Ca2+ for the same binding site. Na + and K+ are equally effective in displacing 45Ca2+ adsorbed to monolayers of phosphatidylserine, both with respect to the kinetics and the equilibrium of the displacement. Ka for the reaction between phosphatidylserine and monovalent cations is about 103-fold smaller than that of Ca2+. An investigation of the binding of Mn2+ to phosphatidylserine by both surface chemical and nuclear magnetic resonance methods shows that this cation has a similar binding constant to that of Ca2+. The Ca2+-binding capabilities of monolayers containing only carboxyl groups (i.e. arachidic acid) and phosphodiester groups (i.e. dicetyl phosphate) have also been determined ; the apparent pK for the—COOH group in monolayers is [This symbol cannot be presented in ASCII format] 9 and that for the phosphodiester group is < 4. Since these groups do not retain the same pK values when they are in close proximity in the phosphorylserine group, the relative contributions of the two groups to the binding of Ca2+ to phosphatidylserine is not obvious. [ABSTRACT FROM AUTHOR]

Surface chemical and nuclear magnetic resonance (NMR) techniques have been used to study the interaction of Ca2+ and lanthanides with lecithins. With both methods positive reactions were detected at metal concentrations > 0.1 mM. ¹H and 31P high-resolution NMR spectra obtained with single bilayer vesicles of lecithin were invariant up to Ca2+ concentrations of 0.1 M indicating that there is only a loose association between Ca2+ and the phospholipid. The weak interaction between Ca2+ and lecithin is confirmed by both surface chemical and NMR techniques showing that the packing of egg lecithin molecules present in bilayers does not change up to Ca2+ concentrations of about 0.1 M. The packing was also independent of pH between 1-10. Contradictory results have been reported in the literature concerning the question of Ca2+ binding to lecithins. The conflicting results are shown to have arisen from differences in the experimental conditions and differences in the sensitivity of the physical methods used by various authors to study Ca2+-lecithin interactions. An estimate of the strength of binding and molecular details of the interaction were derived using paramagnetic lanthanides as isomorphous replacements for Ca2+. From the changes in chemical shifts induced in the presence of lanthanides an apparent binding constant KA ≈ 30 l/mol was calculated at lanthanide concentrations > 10 mM. Using surface chemical methods it was shown that this KA is up to 10 times larger than that for Ca2+ binding. The complete assignment of the ¹H NMR spectrum of lecithin, including the resonances from the relatively immobilized glycerol group, was determined to derive molecular details of the cationlecithin interaction. From spin-lattice relaxation-time measurements and line broadening in the presence of GdCl3 it is concluded that the cations are bound to the phosphate group and that this is the only binding site. The absolute proton shifts induced by paramagnetic lanthanides depended on the nature of the ion, but the shift ratios standardised to the shift of the O3POCH2 (choline) signal were invariant throughout the lanthanide series indicating that the shifts are purely pseudocontact. In contrast the 31P shifts were found to contain significant contact contributions. These findings are consistent with a weak interaction and with the phosphate group being the binding site. The absolute shifts but not the shift ratios depended on the anion present indicating that the cation binding may be accompanied by binding of anions. Contrary to negatively charged phospholipids the interaction of lanthanides with lecithins was enhanced as the ionic strength was increased by adding NaCl. This was explained in terms of stearic hindrance due to the extended conformation of the lecithin polar group. [ABSTRACT FROM AUTHOR]

The morphology and structure of lipoprotein complexes reconstituted from apoprotein from porcine high-density lipoprotein and dimyristoyl lecithin have been studied by a range of physical techniques. At pH 5.6 and ionic strength I ... 0.1. disc-shaped particles are observed with a radius of 4.0-4.5 nm and a thickness of 4.36 ± 0.07 nm. the latter value being in good agreement with that of the average lipid bilayer thickness. The values for the number. weight and Z-average particle weights are Mn = 227000 daltons < Mw = 325000 daltons < Mz = 410000 daltons, respectively. and indicate the polydispersity of these complexes. The number-average particle weight is in good agreement with that of 236000 daltons determined from sedimentation and diffusion experiments. The latter particle weight is also consistent with the particle volume. determined from the dimensions of the disc. and the experimental partial specific volume of the complex. V25 = 0.917 ml/g. At the point inhere all the apoprotein is complexed the average lipid/protein molar ratio is 100 ± 6. Particle size and weight analysis indicate that each lipoprotein disc of radius 4.0-4.5 nm consists of 200 lipid and 2 apoprotein molecules. If lecithin is present in excess of the complex described above, all the lipid may interact with apoprotein up to molar lipid 'protein ratios of 200: 1 depending on the sonication conditions used. The lipoprotein discs undergo an ionic-strength-dependent monomer-dimer equilibrium with low ionic strength leading to the side-by-side aggregation of discs. At an ionic strength I ≈ 0.01 the disc radius is about twice that observed at I ≥ 0.1. The results with dimyristoyl lecithin — apoprotein complexes arc compared with those obtained with dilauroyl and dipalmitoyl lecithin — apoprotein complexes. Lecithin and apoprotein interact to form a loose. disc-shaped complex in which the apoprotein is oriented at the lipid-water (hydrophobic-hydrophilic) interface such that all the polar groups of both lipid and protein are readily accessible to the aqueous medium. Most of the lipid is present as a bilayer, however the cooperative motion of the lipid is significantly reduced due to the interaction with apoprotein. The latter shows a significant increase in α helical content from 50% to about 60-65% when complexed with lecithin. The dispersing (solubilizing) effect which the apoprotein has on unsonicated multilayers of lecithin is explained in terms of its surface activity and conformational properties which magi allow for the regional separation (accumulation) of opposite charges. [ABSTRACT FROM AUTHOR]

Soft machines have recently gained prominence due to their inherent softness and the resulting safety and resilience in applications. However, these machines also have disadvantages, as they respond with complex body dynamics when stimulated. These dynamics exhibit a variety of properties, including nonlinearity, memory, and potentially infinitely many degrees of freedom, which are often difficult to control. Here, we demonstrate that these seemingly undesirable properties can in fact be assets that can be exploited for real-time computation. Using body dynamics generated from a soft silicone arm, we show that they can be employed to emulate desired nonlinear dynamical systems. First, by using benchmark tasks, we demonstrate that the nonlinearity and memory within the body dynamics can increase the computational performance. Second, we characterize our system's computational capability by comparing its task performance with a standard machine learning technique and identify its range of validity and limitation. Our results suggest that soft bodies are not only impressive in their deformability and flexibility but can also be potentially used as computational resources on top and for free. [ABSTRACT FROM AUTHOR]

This paper proposes a new method for real-time terrain recognition-based navigation for mobile robots. Mobile robots performing tasks in unstructured environments need to adapt their trajectories in real-time to achieve safe and efficient navigation in complex terrains. However, current methods largely depend on visual and IMU (inertial measurement units) that demand high computational resources for real-time applications. In this paper, a real-time terrain identification-based navigation method is proposed using an on-board tapered whisker-based reservoir computing system. The nonlinear dynamic response of the tapered whisker was investigated in various analytical and Finite Element Analysis frameworks to demonstrate its reservoir computing capabilities. Numerical simulations and experiments were cross-checked with each other to verify that whisker sensors can separate different frequency signals directly in the time domain and demonstrate the computational superiority of the proposed system, and that different whisker axis locations and motion velocities provide variable dynamical response information. Terrain surface-following experiments demonstrated that our system could accurately identify changes in the terrain in real-time and adjust its trajectory to stay on specific terrain. [ABSTRACT FROM AUTHOR]

The intestinal brush-border membrane contains one or several membrane proteins that mediate fusion and/or aggregation of small unilamellar egg phosphatidylcholine vesicles. The fusion is accompanied by a partial loss of vesicle contents. Proteolytic treatment of the brush-border membrane with proteinase K abolishes the fusogenic property. This finding suggests that the fusogenic activity is associated with a membrane protein exposed on the external or luminal side of the brush-border membrane. Activation of intrinsic proteinases of the brush-border membrane liberates water-soluble proteins (supernate proteins). These proteins behave in an analogous way to intact brush-border membrane vesicles; they induce fusion of egg phosphatidylcholine vesicles and render the egg phosphatidylcholine bilayer permeable to ions and small molecules (Mr < 5000). Furthermore, supernate proteins mediate phosphatidylcholine and cholesterol exchange between two populations of small, unilamellar phospholipid vesicles. Supernate proteins are fractionated on Sephadex G-75 SF yielding three protein peaks of apparent Mr ≥ 70000, Mr = 22000 and Mr = 11500. All three protein fractions show similar phosphatidylcholine-exchange activity, but they differ in their effects on the stability of egg phosphatidylcholine vesicles. The protein fraction with an apparent Mr > 70000 has the highest fusogenic activity while the protein fraction of apparent Mr = 11500 appears to be most effective in rendering the egg phosphatidylcholine bilayer permeable. [ABSTRACT FROM AUTHOR]

A reliable, accurate, and yet simple dynamic model is important to analyzing, designing, and controlling hybrid rigid–continuum robots. Such models should be fast, as simple as possible, and user-friendly to be widely accepted by the ever-growing robotics research community. In this study, we introduce two new modeling methods for continuum manipulators: a general reduced-order model (ROM) and a discretized model with absolute states and Euler–Bernoulli beam segments (EBA). In addition, a new formulation is presented for a recently introduced discretized model based on Euler–Bernoulli beam segments and relative states (EBR). We implement these models in a Matlab software package, named TMTDyn, to develop a modeling tool for hybrid rigid–continuum systems. The package features a new high-level language (HLL) text-based interface, a CAD-file import module, automatic formation of the system equation of motion (EOM) for different modeling and control tasks, implementing Matlab C-mex functionality for improved performance, and modules for static and linear modal analysis of a hybrid system. The underlying theory and software package are validated for modeling experimental results for (i) dynamics of a continuum appendage, and (ii) general deformation of a fabric sleeve worn by a rigid link pendulum. A comparison shows higher simulation accuracy (8–14% normalized error) and numerical robustness of the ROM model for a system with a small number of states, and computational efficiency of the EBA model with near real-time performances that makes it suitable for large systems. The challenges and necessary modules to further automate the design and analysis of hybrid systems with a large number of states are briefly discussed. [ABSTRACT FROM AUTHOR]

Morphological computation can be loosely defined as the exploitation of the shape, material properties, and physical dynamics of a physical system to improve the efficiency of a computation. Morphological control is the application of morphological computing to a control task. In its theoretical part, this article sharpens and extends these definitions by suggesting new formalized definitions and identifying areas in which the definitions we propose are still inadequate. We go on to describe three ongoing studies, in which we are applying morphological control to problems in medicine and in chemistry. The first involves an inflatable support system for patients with impaired movement, and is based on macroscopic physics and concepts already tested in robotics. The two other case studies (self- assembly of chemical microreactors; models of induced cell repair in radio-oncology) describe processes and devices on the micrometer scale, in which the emergent dynamics of the underlying physical system (e.g., phase transitions) are dominated by stochastic processes such as diffusion. [ABSTRACT FROM AUTHOR]

Abstract: We compared cholesterol uptake into brush border membrane vesicles (BBMV) made from the small intestines of either wild-type or Niemann–Pick C1-like 1 (NPC1L1) knockout mice to elucidate the contribution of NPC1L1 to facilitated uptake; this uptake involves cholesterol transport from lipid donor particles into the BBM of enterocytes. The lack of NPC1L1 in the BBM of the knockout mice had no effect on the rate of cholesterol uptake. It follows that NPC1L1 cannot be the putative high-affinity, ezetimibe-sensitive cholesterol transporter in the brush border membrane (BBM) as has been proposed by others. The following findings substantiate this conclusion: (I) NPC1L1 is not a brush border membrane protein but very likely localized to intracellular membranes; (II) the cholesterol absorption inhibitor ezetimibe and its analogues reduce cholesterol uptake to the same extent in wild-type and NPC1L1 knockout mouse BBMV. These findings indicate that the prevailing belief that NPC1L1 facilitates intestinal cholesterol uptake into the BBM and its interaction with ezetimibe is responsible for the inhibition of this process can no longer be sustained. [Copyright &y& Elsevier]

There is now a general consensus that the intestinal absorption of water-insoluble, dietary lipids is protein-mediated, but the assignment of protein(s) to this function is still a matter of debate. To address this issue, we measured β-carotene and cholesterol absorption in wild-type and SR-BI knockout mice and the uptake of these lipids in vitro using brush border membrane (BBM) vesicles. From the comparison of the in vivo and in vitro results we conclude that both BBM-resident class B scavenger receptors, SR-BI and CD36, can facilitate the absorption of β-carotene and cholesterol. SR-BI is essential for β-carotene absorption, at least in mice on a high fat diet. This is due to the fact that the absorption of β-carotene is restricted to the duodenum and SR-BI is the predominant receptor in the mouse duodenum. In contrast, SR-BI may be involved but is not essential for cholesterol absorption in the small intestine. The question of whether SR-BI contributes to cholesterol absorption in vivo is still unresolved. Transfection of COS-7 cells with SR-BI or CD36 confers on these cells lipid uptake properties closely resembling those of enterocytes and BBM vesicles. Both scavenger receptors facilitate the uptake of dietary lipids such as fl-carotene, free and esterified cholesterol, phospholipids, and fatty acids into COS-7 cells. This lipid uptake is effected from three different lipid donor particles: mixed bile salt micelles, phospholipid small unilamellar vesicles, and trioleoylglycerol emulsions which are all likely to be present in the small intestine. Ezetimibe, a representative of a new class of drugs that inhibit intestinal cholesterol absorption, blocks SR-BI- and CD36-facilitated uptake of cholesterol into COS-7 cells. [ABSTRACT FROM AUTHOR]

Investigates the mechanism of long-chain fatty acid in lecithin. Identification of lipid phase; Indication of biological membranes; Steps of fatty acid translocation.

Studies the role of scavenger receptors SR-BI and CD36 in selective sterol uptake in the small intestine. Effect of the lipid composition of high-density lippoprotein (HDL) in cholesterol transfer from reconstituted HDL to brush border membrane vesicles (BBM); Inhibitors of cholesterol and lipid uptake; Composition of scavenger receptors present in the BBM.

Compares the cholesterol and sitosterol uptake in different brush border membranes. Lipid absorption measurements; Occurrence of uptake discrimination; Involvement of esterification into lipoprotein particles; Correlation of uptake to the sterol content of donor; Effect of large quantities of sitosterol in the diet.

The detailed molecular structure of the complex formed by the apoprotein from porcine high density lipoprotein and dimyristoyl phosphatidylcholine (lecithin) has been investigated by a range of physical techniques. The complex, an oblate ellipsoid with major axis 11.0 nm and minor axis 5.5 nm (see the accompanying paper), is comprised of a section of lecithin bilayer with apoprotein at the surface. The main site of interaction between protein and lipid is in the lipid glycerophosphorytcholine group region; as with native high density lipoprotein the surface of the particle consists of a mosaic of lecithin polar groups and protein. The formation of this mosaic reduces the cooperativity of the lecithin chain motions and changes the curvature of the lipid-water interface, as compared to a bilayer. Otherwise, there are no major changes in lecithin motions indicating that no strong binding of lipid to protein occurs. The interaction involves the intercalation of amphipathic, 60 % α-helical, apoprotein molecules among the lecithin molecules so that the protein resides at the lipid-water interface. The apoprotein has a high affinity for the lipid-water interface but specific lipid-protein interactions are not involved. [ABSTRACT FROM AUTHOR]

• Simple kinematic principles lead to emerging behaviours for hyper-redundant robots. • Primal behaviours can be managed by motion strategies to create high-level controls. • A unified framework gathers the underlying kinematics of highly-articulated systems. The purpose of this work consists of finding a simple and general method to control hyper-redundant manipulators. By definition, hyper-redundant robots have a large number of degrees of freedom which makes it difficult to find fast and stable solutions. In the case of growing robots, where the number of degrees of freedom can even increase, the problem is exacerbated. This work proposes a new approach. By modifying and reinterpreting the three basic variables needed for operation in a three-dimensional space, our framework gives rise to a number of novel, decentralized control behaviours. These behaviours were not designed but rather emerged as a result of cyclical, incremental and uniform movements in the robot body. They include different modes of attraction, repulsion, surrounding, straightening, folding and circumnutations. As opposed to traditional control approaches which are typically programmed for one specific application, this framework provides a set of general behaviours that can be combined using different motion strategies for a wide number of applications. We demonstrate the usefulness of this approach in a number of scenarios for hyper-redundant and growing robots. [ABSTRACT FROM AUTHOR]