German firm Festo put out this cool visualization of a robotic tentacle arm; it would be actuated by air pressure rather than the usual servomechanisms.
(Robotic 'Handling Assistant')
H.G. Wells was the first one to paint this picture in fiction (as far as I know); readers recall the steel tentacles from his 1898 novel War of the Worlds:
Seen nearer, the Thing was incredibly strange, for it was no mere insensate machine driving on its way. Machine it was, with a ringing metallic pace, and long, flexible, glittering tentacles (one of which gripped a young pine tree) swinging and rattling about its strange body.
Wearable Artificial Fabric Muscles
'It is remarkable that the long leverages of their machines are in most cases actuated by a sort of sham musculature...' HG Wells, 1898.
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