Fig. 1 Schematics of positive- and negative-stiffness mechanisms in which the solid lines represent the system in a released state while the dotted lines represent the system in a compressed state. Step 1: Compressed from points c to a; Step 2: Released from points a to b; Step 3: Released from po... More about this image found in Schematics of positive- and negative-stiffness mechanisms in which the soli...

Fig. 2 Working principle of the conventional Linear DEAs: ( a ) Initial dimensions of the elastomer; ( b ) pre-stretched state of a constant load linear DEA; ( c ) powered-on state of a constant load linear DEA; ( d ) pre-stretched state of a linear DEA using positive-stiffness compression spring;... More about this image found in Working principle of the conventional Linear DEAs: ( a ) Initial dimensions...

Fig. 3 Force analysis of linear DEAs with three different types of tensioning mechanism More about this image found in Force analysis of linear DEAs with three different types of tensioning mech...

Fig. 4 Schematics and characterization of butterfly-shaped linear DEA: ( a ) conceptual design and ( b ) CAD model of the butterfly-shaped system; ( c ) details of the revolute joint used in the butterfly-shaped linear DEA; ( d ) force–length relationship of silicone film-M1; (the force data of si... More about this image found in Schematics and characterization of butterfly-shaped linear DEA: ( a ) conce...

Fig. 5 Schematics and characterization of X-shaped linear DEA: ( a ) CAD model of the X-shaped tensioning mechanism (M2); ( b ) CAD model of the X-shaped linear DEA; ( c ) exploded view of X-shaped linear DEA; ( d ) details of the torsional spring position on inclined links in X-shaped tensioning ... More about this image found in Schematics and characterization of X-shaped linear DEA: ( a ) CAD model of ...

Fig. 6 Fabrication of the dielectric layer (silicone film and electrode): ( a ) silicone film strip; ( b ) Uniaxial stretching mechanism CAD model and photograph; ( c ) fixing the silicone film onto stretching mechanism; ( d ) pre-stretching the silicone film; ( e ) put the mask onto the silicone ... More about this image found in Fabrication of the dielectric layer (silicone film and electrode): ( a ) si...

Fig. 7 Key steps for the fabrication of a butterfly-shaped linear DEA: ( a ) the silicone film; ( b ) details of the tensioning mechanism; ( c ) force–length relationship of the tensioning mechanism (solid line) and the silicone film (dotted line); ( d ) the pre-assembly condition of the silicone ... More about this image found in Key steps for the fabrication of a butterfly-shaped linear DEA: ( a ) the s...

Fig. 8 Linear DEA prototypes: ( a ) butterfly-shaped linear DEA; ( b ) X-shaped linear DEA; ( c ) positive-stiffness mechanism linear DEA; ( d ) constant load linear DEAs with (1) single and (2) double layer of elastomers More about this image found in Linear DEA prototypes: ( a ) butterfly-shaped linear DEA; ( b ) X-shaped li...

Fig. 9 Details of the analytical model for the new class of ASL-DEAs: ( a ) schematics of the dynamic model of the ASL-DEAs; ( b ) dimensions of the elastomer after being stretched; ( c ) schematics of the butterfly-shaped tensioning mechanism; ( d ) schematics of the X-shaped tensioning mechanism... More about this image found in Details of the analytical model for the new class of ASL-DEAs: ( a ) schema...

Fig. 10 Experimental setup for assessing the linear DEA performances: ( a ) the setup used to measure the stroke; ( b ) the setup to measure the output force More about this image found in Experimental setup for assessing the linear DEA performances: ( a ) the set...

Fig. 11 ( a ) The comparison of the experimental stroke and output force of the butterfly-shaped, X-shaped, constant-load, and positive-stiffness linear DEAs, with the error bars showing the standard deviation over five cycles; ( b ) the comparison of the experimental peak stroke for the X-shaped ... More about this image found in ( a ) The comparison of the experimental stroke and output force of the but...

Fig. 12 The dynamical response comparison between the theoretical and experimental data of the butterfly- and X-shaped linear DEA: ( a ) actuation signal I; ( b ) Actuation signal II; ( c ) stroke–time curve of the butterfly-shaped linear DEA in actuation signal I; ( d ) stroke–time curve of the b... More about this image found in The dynamical response comparison between the theoretical and experimental ...