Shadow Hand
Encyclopedia
Humanoid
A humanoid is something that has an appearance resembling a human being. The term first appeared in 1912 to refer to fossils which were morphologically similar to, but not identical with, those of the human skeleton. Although this usage was common in the sciences for much of the 20th century, it...
robot
Robot
A robot is a mechanical or virtual intelligent agent that can perform tasks automatically or with guidance, typically by remote control. In practice a robot is usually an electro-mechanical machine that is guided by computer and electronic programming. Robots can be autonomous, semi-autonomous or...
hand
Hand
A hand is a prehensile, multi-fingered extremity located at the end of an arm or forelimb of primates such as humans, chimpanzees, monkeys, and lemurs...
system developed by The Shadow Robot Company in London
London
London is the capital city of :England and the :United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located on the River Thames, London has been a major settlement for two millennia, its history going back to its...
. The hand is comparable to a human hand in size and shape, and reproduces all of its degrees of freedom. The Hand is commercially available and currently used by NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
, Bielefeld University
Bielefeld University
Bielefeld University is a university in Bielefeld, Germany. Founded in 1969, it is one of the country's newer universities, and considers itself a "reform" university, following a different style of organization and teaching than the established universities...
and Carnegie Mellon University
Carnegie Mellon University
Carnegie Mellon University is a private research university in Pittsburgh, Pennsylvania, United States....
.
Form factor
The Shadow Dexterous Hand has been designed to be as similar as possible to the average hand of the human male. The forearm structure is comparable in length to the human forearm, although at the base it widens to 146 mm.Degrees of freedom
The Shadow Dexterous Hand has been designed to have a range of movement equivalent to that of a typical human being.The four fingers of the hand contain two one-axis joints connecting the distal phalanx
Phalanx bones
In anatomy, phalanx bones are those that form the fingers and toes. In primates such as humans and monkeys, the thumb and big toe have two phalanges, while the other fingers and toes consist of three. Phalanges are classified as long bones.The phalanges do not have individual names...
, middle phalanx and proximal phalanx and one universal joint
Universal joint
A universal joint, universal coupling, U joint, Cardan joint, Hardy-Spicer joint, or Hooke's joint is a joint or coupling in a rigid rod that allows the rod to 'bend' in any direction, and is commonly used in shafts that transmit rotary motion...
connecting the finger to the metacarpal.
The little finger has an extra one-axis joint on the metacarpal to provide the Hand with a palm curl movement.
The thumb contains one one-axis joint connecting the distal phalanx to the proximal phalanx, one universal joint connecting the thumb to the metacarpal and one one-axis joint on the bottom of the metacarpal to provide a palm curl movement.
The wrist contains two joints, providing flex/extend and adduct/abduct.
This means that the Shadow Dexterous hand has 24 joints all together, with 20 degrees of freedom.
Actuation
The movements of the hand are powered by a set of 40 Air MusclesPneumatic artificial muscles
Pneumatic artificial muscles are contractile or extensional devices operated by pressurized air filling a pneumatic bladder. In a vague approximation of human muscles, PAMs are usually grouped in pairs: one agonist and one antagonist....
in the forearm. The flow of air into and out of each muscle is controlled by eighty valve
Valve
A valve is a device that regulates, directs or controls the flow of a fluid by opening, closing, or partially obstructing various passageways. Valves are technically pipe fittings, but are usually discussed as a separate category...
s, also in the forearm. This is done based on the information gathered from the joint sensors.
History
The Shadow Dexterous Robot Hand is the first commercially available robot hand from the company, and follows a series of prototypePrototype
A prototype is an early sample or model built to test a concept or process or to act as a thing to be replicated or learned from.The word prototype derives from the Greek πρωτότυπον , "primitive form", neutral of πρωτότυπος , "original, primitive", from πρῶτος , "first" and τύπος ,...
humanoid hand and arm systems.
Further reading
Transformation of Shadow Dextrous Hand and Shadow Finger Test Unit from Prototype to Product for Intelligent Manipulation and Grasping, Marco Reichel, The Shadow Robot Company, Intelligent Manipulation and Grasping, International Conference, July 1–2, 2004, Genova - ItalyItaly
Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...