Joint assemblies with cross-axis flexural pivots
The embodiments described herein can be used in a variety of grasping, cutting, and manipulating operations. In some embodiments, an apparatus includes a first joint member, a second joint member, and a flexure. The first joint member includes a first connection portion and a contact surface. The second joint member including a second connection portion. A first end portion of the flexure is coupled to the first connection portion, and a second end portion of the flexure is coupled to the second connection portion. The flexure is configured to deform elastically when the first joint member and the second joint member move from a first configuration to a second configuration. When in the first configuration, the central portion of the flexure is spaced apart from the contact portion. When in the second configuration, the central portion of the flexure contacting the contact portion.
1. An apparatus, comprising:
a first joint member;
a second joint member;
a third joint member between the first joint member and the second joint member;
a first flexure comprising a first end portion and a second end portion, the first end portion of the first flexure being coupled to the first joint member, the second end portion of the first flexure being coupled to the third joint member, and the first flexure being configured to deform elastically when the second joint member rotates relative to the first joint member about a first axis of rotation; and
a second flexure comprising a first end portion and a second end portion, the first end portion of the second flexure being coupled to the second joint member, the second end portion of the second flexure being coupled to the third joint member, the second flexure being configured to deform elastically when the second joint member rotates relative to the first joint member about a second axis of rotation, and the second axis of rotation intersects and is nonparallel to the first axis of rotation,
at least one of the first joint member and the third joint member comprises a contact surface;
the first flexure comprises a central portion between the first end portion of the first flexure and the second end portion of the first flexure;
the first flexure is configured to transition between a first configuration and a second configuration when the second joint member rotates relative to the first joint member about the first axis of rotation,
the central portion of the first flexure is spaced apart from the contact surface when the first flexure is in the first configuration, and
the central portion of the first flexure is in contact with the contact surface when the first flexure is in the second configuration.
2. The apparatus of claim 1 , wherein:
the first joint member, the second joint member, and the third joint member define a longitudinal axis when the first joint member, the second joint member, and the third joint member are in a first configuration; and
the first axis of rotation and the second axis of rotation are each normal to the longitudinal axis.
3. The apparatus of claim 1 , wherein:
the first joint member comprises a connection portion;
the third joint member comprises a connection portion;
the first end portion of the first flexure is coupled to the connection portion of the first joint member;
the second end portion of the second flexure is coupled to the connection portion of the third joint member; and
a plane defined by the connection portion of the first joint member is substantially coplanar with a plane defined by the connection portion of the third joint member.
4. The apparatus of claim 1 , wherein the first joint member, the first flexure, and the third joint member are monolithically formed.
5. An apparatus, comprising:
a first joint member;
a second joint member;
a third joint member between the first joint member and the second joint member;
a first flexure comprising a first end portion and a second end portion, the first end portion of the first flexure being coupled to the first joint member, the second end portion of the first flexure being coupled to the third joint member, and the first flexure being configured to deform elastically when the second joint member rotates relative to the first joint member about a first axis of rotation; and
a second flexure comprising a first end portion and a second end portion, the first end portion of the second flexure being coupled to the second joint member, the second end portion of the second flexure being coupled to the third joint member, the second flexure being configured to deform elastically when the second joint member rotates relative to the first joint member about a second axis of rotation, and the second axis of rotation intersects and is nonparallel to the first axis of rotation,
at least one of the second joint member and the third joint member comprises a contact surface;
the second flexure comprises a central portion between the first end portion of the second flexure and the second end portion of the second flexure,
the second flexure is configured to transition between a first configuration and a second configuration when the second joint member rotates relative to the first joint member about the second axis of rotation,
the central portion of the second flexure is spaced apart from the contact surface when the second flexure is in the first configuration, and
the central portion of the second flexure is in contact with the contact surface when the second flexure is in the second configuration.
6. The apparatus of claim 5 , wherein:
the first joint member, the second joint member, and the third joint member define a longitudinal axis when the first joint member, the second joint member, and the third joint member are in a first configuration; and
the first axis of rotation and the second axis of rotation are each normal to the longitudinal axis.
7. The apparatus of claim 5 , wherein:
the first joint member comprises a connection portion;
the third joint member comprises a connection portion;
the first end portion of the first flexure is coupled to the connection portion of the first joint member;
the second end portion of the second flexure is coupled to the connection portion of the third joint member; and
a plane defined by the connection portion of the first joint member is substantially coplanar with a plane defined by the connection portion of the third joint member.
8. The apparatus of claim 5 , wherein the first joint member, the first flexure, and the third joint member are monolithically formed.