Early robotic hands were developed in part to mimic human grasping, but mostly to function in industrial environments where speed and force of operation were primary objectives.
More recently, some robot hand R&D has focused on closely emulating the human ability to pick up; manipulate; and move small, delicate objects in unstructured environments outside the factory safety cage. Many of these robots are being developed for use with humans, either in industrial environments, or as service robots for the elderly or disabled.
This requires robots that are smaller, safer, and human-aware at some level. Engineers developing the newer generation of robotic hands have re-thought the approach to hand design. Many have started with a higher-level view that attempts to emulate multiple integrated human biological systems, not only motor movements. The newer generation of robotic hands closely models the human hand's kinematics with a similar form factor, tactile and sometimes optical sensors, and high degrees of freedom (DOF) counts. Many have industry-standard interfaces and can be used as a tele-operation tool or mounted on a range of robot arms as part of a robot system. Some are commercially available, some were developed as proof-of-concept, and some are still in R&D.
Click on the image below to see 11 of these robots.
Based on the DLR Hand II, the German Aerospace Center (DLR) and the Harbin Institute of Technology (HIT) jointly developed the DLR/HIT Hand II as a medium-cost multisensory robotic hand. The DLR/HIT Hand II has five fingers, each with three actuators, that are identical except that one of them has an additional drive to make it work as an opposing thumb. To fully emulate human fingers' motor functions, each finger has four joints, not three, and each joint has force and position sensors. The DLR/HIT Hand II has a total of 15 degrees of freedom (DOF), compared to 13 in the original DLR Hand II. Fingers are equipped with slip-resistant gripper surfaces. Integration of drives and electronics within the hand itself is intended to make it easier to mount on a wide variety of robot arms.
(Source: German Aerospace Center (DLR))