Abstract: A flexible unit-cell actuator includes a shape memory alloy sheet having a fold between adjacent legs in one state and a heat source that upon activation concentrates heating of the shape memory alloy sheet at the fold relative to the legs to change the fold between one state and another state. The heat source may include resistive heating due to an electric current passing through the shape memory alloy sheet. The fold typically includes a reduced cross-sectional area and may include slits to increase electrical resistance at the fold relative to the adjacent legs. An actuator array includes a plurality of flexible unit-cell actuators formed in a sheet, each unit-cell actuator mechanically coupled to at least one other unit-cell actuator at a coupling region. Plural unit-cell actuators may be mechanically coupled in series, in parallel, or both, may be electrically connected in series, and may move along a defined curve or surface.

Abstract: A robotic finger that includes multiple phalanges, each phalange configured to be compliantly actuated. The robotic finger also includes compliant touch sensors that, in combination with the compliant actuation, provides the robotic finger with two levels of compliance. The two levels of compliance enable the robotic finger to gently conform to and manipulate objects.

Abstract: A robotic finger that includes multiple phalanges, each phalange configured to be compliantly actuated. The robotic finger also includes compliant touch sensors that, in combination with the compliant actuation, provides the robotic finger with two levels of compliance. The two levels of compliance enable the robotic finger to gently conform to and manipulate objects.

Abstract: A flexible unit-cell actuator includes a shape memory alloy sheet having a fold between adjacent legs in one state and a heat source that upon activation concentrates heating of the shape memory alloy sheet at the fold relative to the legs to change the fold between one state and another state. The heat source may include resistive heating due to an electric current passing through the shape memory alloy sheet. The fold typically includes a reduced cross-sectional area and may include slits to increase electrical resistance at the fold relative to the adjacent legs. An actuator array includes a plurality of flexible unit-cell actuators formed in a sheet, each unit-cell actuator mechanically coupled to at least one other unit-cell actuator at a coupling region. Plural unit-cell actuators may be mechanically coupled in series, in parallel, or both, may be electrically connected in series, and may move along a defined curve or surface.