Spherical dexterous hand for object grasping and within-hand manipulation
View Patent ↗Structural designs and operational methods for object grasping and within-hand manipulation of an object is provided using rolling structures. The use of rolling structures reduces the need of finger gaiting, which is the periodic relocation of fingers on the object while maintaining a grasp, during manipulation. Embodiments of the invention provide a more efficient method of in-hand manipulation and grasping. In one example, two degrees of freedom rollers allow the object being manipulated in any direction in 3D space while remaining contact with the object.
1 . A robotic hand, comprising:
a plurality of fingers each with a distal end and a proximal end,
wherein at the distal end,
of each of the plurality of fingers a rolling structure is connected, wherein the rolling structure is capable of rotating about a first axis with respect to the distal end of the respective finger,
wherein the rolling structure is further capable of rotating about a second axis with respect to the distal end of the respective finger,
wherein the first axis and the second axis are coupled axes and substantially orthogonal to each other,
wherein the first axis and the second axis are each actuated independently from each other with an actuator, and
wherein the plurality of fingers are spaced and orientated with respect to each other such that the rolling structures are capable of manipulating an object.
2 . The robotic hand as set forth in claim 1 , wherein at the proximal end each finger of the plurality of fingers is capable of rotating around a third axis, wherein rotation around the third axis creates a grasping degree of freedom for each of the fingers, wherein the rotation around the third axis is actuated independently for each of the plurality of fingers, and wherein the rotation around the third axis enables the plurality of fingers to grasp objects of various sizes and shapes.
3 . The robotic hand as set forth in claim 2 , wherein the third axis is substantially orthogonal to either the first axis or the second axis.
4 . The robotic hand as set forth in claim 1 , wherein the rotation around the first axis enables what is referred to as a steering motion and the rotation around the second axis enables what is referred to as a rolling motion, therewith together capable of rolling and steering the object when held in between the rolling structures of the plurality of fingers.
5 . The robotic hand as set forth in claim 1 , wherein each rolling structure is a spherical rolling structure or a cylindrical rolling structure.
6 . The robotic hand as set forth in claim 1 , wherein the rolling structure spherical, or cylindrical.
7 . The robotic hand as set forth in claim 1 , wherein the plurality of fingers is two or more fingers.
8 . The robotic hand as set forth in claim 1 , wherein at least one of the plurality of fingers is an articulated multi-segmented finger.
9 . The robotic hand as set forth in claim 1 , wherein the rolling structure comprises tactile sensors either on a surface of each rolling structure, embedded in each rolling structure, or a combination thereof.
10 . A method of grasping and manipulating an object, comprising:
(a) having a robotic hand with a plurality of fingers each with a distal end and a proximal end,
wherein at the distal end
of each of the plurality of fingers a rolling structure is connected, wherein the rolling structure is capable of rotating about a first axis with respect to the distal end of the respective finger,
wherein the rolling structure is further capable of rotating about a second axis with respect to the distal end of the respective finger,
wherein the first axis and the second axis are coupled axes and substantially orthogonal from each other,
wherein the first axis and the second axis are each actuated independently from each other with an actuator;
(b) manipulating the object by independently controlling the one or more of the first axis, second axis and the third axis associated with the one or more of the plurality of fingers.