Device and method of fabrication for dexterous continuum tensegrity manipulator
View Patent ↗A continuum manipulator that comprises an assembly of ‘vertebra’-like modules fabricated using two curved links and twelve strings and actuated using Motor-Tendon Actuators. The modules being modeled as tensegrity structures having a polyhedron shape. The vertices and edges of the tensegrity structure polyhedron correspond to the holes and strings or links of the structure. Furthermore, a mobile continuum manipulator that includes a control unit and wheels or mobile legs.
1 . A manipulator comprising a plurality of modules interlocked to form a linear arrangement of modules, wherein a module comprises:
two rigid elements each defining a plurality of connection holes, wherein the two rigid elements do not touch, wherein each of the two rigid elements comprises an assembly connector, whereby the plurality of modules are coupled by interlocking assembly connectors of respective modules; and
a single continuous string or cord routed through the plurality of connection holes of the two rigid elements to form a plurality of tension-compliant elements extending between the two rigid elements.
2 . The manipulator of claim 1 , wherein at least one of the two rigid elements comprises a two-dimensional shape forming a half-circle and the assembly connector is oriented radially.
3 . The manipulator of claim 1 , wherein the single continuous string or cord is a prestressed string or cord.
4 . The manipulator of claim 1 , wherein the module comprises a polyhedron shape, wherein edges and vertices of the polyhedron shape are formed by the plurality of tension-compliant elements and the plurality of connection holes of the two rigid elements.
5 . The manipulator of claim 1 , wherein the plurality of modules are rigidly coupled by interlocking the assembly connector of respective modules.
6 . The manipulator of claim 1 , wherein the plurality of tension-compliant elements are secured to the two rigid elements with a rigid assembly, wherein the rigid assembly prevents movement between a tension compliant element and a rigid element.
7 . The manipulator of claim 1 , wherein the module further comprises a first tendon connector and a second tendon connector each oriented radially and equally spaced on either side of the assembly connector, the first and second tendon connectors each comprising a tendon attachment, wherein each tendon attachment comprises a hole through which a tendon is positioned.
8 . The manipulator of claim 7 , further comprising a plurality of actuators positioned at a proximal end of the manipulator, a plurality of tendons connecting the plurality of actuators and the plurality of modules, and a means for gripping at a distal end of the manipulator, wherein a number of tendons and number of actuators are the same.
9 . The manipulator of claim 8 , wherein the plurality of actuators comprises motor-tendon actuators.
10 . The manipulator of claim 8 , comprising ten modules, four tendons, and four actuators, wherein each module comprises twelve tension-compliant elements formed by the single continuous string or cord and four holes in each of the two rigid elements.
11 . A device comprising a plurality of manipulators of claim 10 .
12 . The device of claim 11 , further comprising a base plate, wherein the base plate is positioned above the plurality of actuators and below a first module from the proximal end of the plurality of manipulators.
13 . The device of claim 11 , further comprising a base housing, wherein the base housing encases the plurality of actuators and a control unit, and wherein a plurality of wheels and mounts are coupled to the base housing.
14 . The manipulator of claim 8 , further comprising a base plate, wherein the base plate is positioned above the plurality of actuators and below a first module from the proximal end of the manipulator.
15 . The manipulator of claim 14 , further comprising a base housing, wherein the base housing encases the plurality of actuators, and a control unit.
16 . The manipulator of claim 15 , wherein a plurality of wheels or a plurality of mobile legs are coupled to the base housing.
17 . The manipulator of claim 8 , wherein one or more sensors are coupled to the modules of the manipulator.
18 . The manipulator of claim 1 , wherein the two rigid elements of the module comprises a first rigid element and a second rigid element oriented at a 90-degree angle to the first rigid element relative to a longitudinal axis of the linear arrangement of modules.
19 . The manipulator of claim 1 , wherein the module is a first module comprising a first rigid element and a second rigid element, wherein the assembly connector of the first rigid element projects from the first rigid element to interlock and overlap with at least a portion of an assembly connector of a third rigid element of a second module.
20 . The manipulator of claim 1 , further comprising one or more pinch points disposed in at least one of the plurality of connection holes, the one or more pinch points being adjustable to adjust tension in the single continuous string or cord.