The new planar technology for manufacturing fluidic drives and kinematics was therefore ideally suited for actively moving miniature catheters and endoscopes. However, the forces achievable with planar film drives, which operate at a working pressure of 0.5-1 bar, were too low for the construction of an artificial hand. To generate higher grasping forces, a correspondingly higher working pressure had to act in the fluidic drives. For Fluidhand 2, “artificial muscles” based on thin silicone hoses were therefore used, which were sheathed with a flexurally flexible, stretch-resistant fabric made of polyamide.

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The tubes of the Fluidhand 2 were unfolded in the finger joints. When subjected to an overpressure of up to 4 bar, the joints expanded unilaterally and realized a curvature in the opposite joint direction. Each finger of the hand has two pneumatic muscles, the thumb has three, the wrist has four. The extension is done by a rubber band. The joint and support structure in the fingers, thumb and hand, was made of fiber-reinforced composite material. The artificial hand scored with its consistently soft and compliant structure, very fast movements and pronounced adaptability when grasping. The grasping forces achieved were around 2.5 N per finger. Objects heavier than 500 g could not yet be grasped with this hand. As in Fluidhand 1, the hand was driven by compressed air, which meant that a powerful compressor was required to operate the hand.