Active deformability

Low number of surfaces (6) for the complete range of wavefront control functions field stabilization, active focusing and centering, actively deformable surfaces, dual conjugates adaptive optics ... 

Jones CH, Unruh JR, Sonder LJ (1996) The role of gravitational potential energy in active deformation in the southwestern United States. Nature 381(6577) 37-41... 

Surface Carbonate, Nitrate and Borate Species As already reported (Table 3.5), free carbonate, nitrate and borate ions, as a result of their trigonal D31, symmetry, have one characteristic strong IR vibration (V3 asymmetric XO stretch) found near 1480 cm for borates, 1415 cm" for carbonates and near 1380 cm" for nitrates, together with two lower frequency IR-active deformation modes. 

An alternative model is shown schematically in Fig. 10. Just as for the craze tip, the strain-softened polymer being actively deformed at the bulk polymer interface is idealized as a thin layer of non-Newtonion fluid. The velocity v of plastic advance of the craze interface depends on the gradient in hydrostatic tension Van as... 

Active deformability. If the capability to squeeze through tissues is an important step for most metastatic cells, then a selection based on the ability of cells to cross filter holes about ten times smaller than their cellular diameter should theoretically yield cells with a higher metastatic capability (Tullberg and Burger, 1985). The selection procedure is deseribed in Chapter 6. 

Fig. 1. Convection of material into a stable craze fibril through an active deformation layer.

Fig. 8. Matrix porosity versus permeability reduction in faults. The upper trend describes the range of permeabilities observed within actively deforming cataclastic deformation bands. Permeabilities ate enhanced at low porosities, and slightly reduced at high porosities. The lower trend describes how inactive faults after burial show highly reduced permeability relative to the matrix. This permeability reduction gets more significant with increasing matrix porosity.

Capaldi, F. M., Boyce, M. C., and Rutledge, G. C. (2002) Enhanced mobility accompanies the active deformation of a glassy amorphous polymer, Phys. Rev. Lett, 89,175505 (1-4). 

Fig. 13.23 Calculated contours of iso-strain rate in the shoulder region of a plastically stretching bar, as an analog of the actively deforming base of a craze fibril. The central zone of thickness ad having the highest plastic-strain rate and the highest steady-state content of liquid-like material acts as a preferential conduit for the penetration of plasticizing diluent (from Argon (1999) courtesy of Wiley).

Under the continuous earthquake activities, deformation was ongoing and the hypergene fissures developed more quickly. When the tensile fractures in the scarp deepened later on to a certain depth, the stress accumulation around the locked patches brought this part of the rock into an accelerated creep stage. After a strong earthquake, the still intact patches were broken along the sliding plane, which led to the development of the landslide. 

What is the fundamental problem essential to deformable machines consisting of actively deformable material It is organized into two major problems, which originate from activeness and deformability of the machines. 

Major problems of deformable machines consisting of actively deformable... 

Actively deformable materials work imder their dynamical laws, which should help to solve the degrees of freedom problem of deformable machines. Here, the relationship between deformability problem and activeness problem is suggested. 

The best way to discover concrete methods is to prototype machines from existing material. Real things tell us many things. Constitutive approach was taken for solving the above problems. Deformable robots were experimentally developed made entirely of electroactive polymer gel, hereafter called, gel robots . The purpose of gel robots is to discover fundamental principles for designing and controlling deformable machine made of actively deformable materials. Ideas are explored which solve the major problems of activeness and deformability. 

There are two directions of machines with actively deformable materials. One is to replace conventional actuators to muscle-like bundles that shrink or stretch. Another direction is to build machine with distributed muscle like structures. The latter is not an extension of conventional machines, and requires methodology to solve major problems. The latter direction is focused on in this study. 

With these policies described above, we selected materials to build deformable machines. Prom among variety of actively deformable materials, we selected electroactive pol3rmer gel, Poly (2-acrylamido-2-methylpropane sulfonic acid) gel (PAMPS gel) [61, 128] which is capable of large deformations although the response speed is not so fast. The main advantage of this material is that transformation can be halted if required. In order to remove the effects of wires and to focus on the major problems, gel robots were controlled by electric fields. 

There didn t exist deformable machine made entirely of actively deformable material. This is the reason why the design stage was required. Model enabled me to design innovative mechanisms. There are two advantages for modelling based... 

Purpose of chapter 2 is to understand the characteristics of actively deformable materials through modelling. Since electroactive polymer gel is dealt with, its activeness comes from the electrochemical property. It has been believed that electrochemical reaction must be modeled thoroughly to predict the process precisely. This common sense stated in this chapter is challenged. 

Chapter 6 deals with shape design of deformable machines. Manufacturing process is developed to form actively deformable materials as desired. Previous approach to design deformable machine was to divide the stiff element into small pieces and add controllable or passive joints[162, 163]. The reversed approach was taken. 

This chapter proposes a model for predicting deformation response of deformable machines consisting of actively deformable materials. This is an attempt to im-derstand activeness and deformability through description. The performance measure of the trial is simplicity and outlook of the model. We try to make up strategy to convert uncontrollable material into controllable mechanism. 

It has been proposed numerous models to describe actively deformable materials, especially electroactive polymers. Novel model is proposed because of the characteristics of the previous one. 

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