Shape-memory effector systems
An effector system includes: a plurality of effector assemblies configured to engage a target object; a base having a plurality of mounting surfaces for movably supporting the effector assemblies; a plurality of actuators coupled to the base, each actuator including: an actuator housing defining a conduit having a first end and a second end; an output member slidable within the conduit; a first shape-memory transducer affixed between the first end and the output member; a second shape-memory transducer affixed between the second end and the output member; an electrical subassembly configured to control each actuator to cause the output member to slide towards a selected one of the first end and the second end; and a plurality of linkages between respective output members and effector assemblies, each linkage configured to move a corresponding effector assembly relative to the base in response to sliding of the respective output member.
1. An effector system, comprising:
a plurality of effector assemblies configured to engage a target object;
a base having a plurality of mounting surfaces for movably supporting the effector assemblies;
a plurality of actuators coupled to the base, each actuator including:
an actuator housing defining a conduit having a first end and a second end;
an output member slidable within the conduit;
a first shape-memory transducer affixed between the first end and the output member;
a second shape-memory transducer affixed between the second end and the output member;
an electrical subassembly configured to control each actuator to cause the output member to slide towards a selected one of the first end and the second end; and
a plurality of linkages between respective output members and effector assemblies, each linkage configured to move a corresponding effector assembly relative to the base in response to sliding of the respective output member.
2. The effector system of claim 1 , wherein the electrical subassembly is configured to control each actuator by:
selectively supplying current to (i) bias the first shape-memory transducer to a first memory state and bias the second shape-memory transducer to a second deformed state, for sliding the output member in a first direction, or (ii) bias the second shape-memory transducer to a second memory state and bias the first shape-memory transducer to a first deformed state, for sliding the output member in a second direction.
3. The effector system of claim 1 , wherein the base includes a front surface, and wherein each mounting surface includes a joint socket defined in the front surface.
4. The effector system of claim 3 , wherein the base includes a rear surface carrying at least one of the actuators.
5. The effector system of claim 4 , wherein the base includes a first rear surface carrying a first subset of the actuators, and a second rear surface carrying a second subset of the actuators.
6. The effector system of claim 1 , wherein the plurality of actuators is equal in number to the plurality of effector assemblies.
7. The effector system of claim 1 , wherein the base further comprises:
an inlet;
an outlet at one of the mounting surfaces; and
a conduit extending through the base from the inlet to the outlet.
8. The effector system of claim 7 , wherein the base further comprises:
respective outlets at each mounting surface;
a first conduit extending into the base from the inlet; and
respective second conduits extending from each outlet to the first conduit.
9. The effector system of claim 7 , further comprising:
a vacuum source configured to apply a vacuum to the inlet for transmission of the vacuum to the outlet via the conduit;
wherein each effector assembly defines an additional conduit in communication with the conduit, and terminating at a distal effector outlet for applying the vacuum to the target object.
10. The effector system of claim 1 , wherein the plurality of linkages includes, for each actuator:
a first linkage between the output member and a first side of a corresponding effector assembly; and
a second linkage between the output member and a second side of the corresponding effector assembly.
11. The effector system of claim 1 , wherein
the output member of each actuator electrically isolates the first shape-memory transducer from the second shape-memory transducer, and includes a conductive outer surface; and
an inner surface of the actuator housing is conductive.
12. The effector system of claim 11 , wherein each actuator further comprises:
a first electrical connection at the first end for applying a current to the first shape-memory transducer;
a second electrical connection at the second end for applying a current to the second shape-memory transducer; and
a ground connection to the conductive inner surface of the actuator housing, between the first end and the second end.
13. A base assembly for an effector system, the base assembly comprising:
a base having a plurality of mounting surfaces for movably supporting corresponding effector assemblies; and
a plurality of actuators coupled to the base, each actuator including:
an actuator housing defining a conduit having a first end and a second end;
an output member slidable within the conduit;
a first shape-memory transducer affixed between the first end and the output member;
a second shape-memory transducer affixed between the second end and the output member.
14. The base assembly of claim 13 , further comprising a plurality of linkages between respective output members and effector assemblies, each linkage configured to move a corresponding effector assembly relative to the base in response to sliding of the respective output member.
15. The base assembly of claim 13 , wherein the base includes a forward surface, and wherein each mounting surface includes a joint socket defined in the forward surface.
16. The effector system of claim 15 , wherein the base includes a rear surface carrying at least one of the actuators.
17. The effector system of claim 16 , wherein the base includes a first rear surface carrying a first subset of the actuators, and a second rear surface carrying a second subset of the actuators.
18. The effector system of claim 13 , wherein the base further comprises:
an inlet;
an outlet at one of the mounting surfaces; and
a conduit extending through the base from the inlet to the outlet.
19. The effector system of claim 18 , wherein the base further comprises:
respective outlets at each mounting surface;
a first conduit extending into the base from the inlet; and
respective second conduits extending from each outlet to the first conduit.