Robotic finger exoskeleton
The present disclosure includes a finger exoskeleton including a plurality of joints and a plurality of sensors configured to measure rotation of at least some of the plurality of joints of the finger exoskeleton. The finger exoskeleton also includes a series elastic actuator comprising a spring element, the series elastic actuator configured to rotate at least one of the plurality of joints. The finger exoskeleton also includes a computing device configured to control operation of the series elastic actuator based on a torque of the at least one of the plurality of joints, the torque determined at least based on the spring element and rotation of the at least one of the plurality of joints. The present disclosure also includes associated methods and hand exoskeletons.
1. A finger exoskeleton comprising:
a plurality of joints;
a plurality of sensors configured to measure rotation of at least some of the plurality of joints of the finger exoskeleton;
a first series elastic actuator comprising a spring element, the first series elastic actuator configured to rotate at least one of the plurality of joints;
a sliding joint configured to translate one or more lateral forces applied to the at least one of the plurality of joints into a normal reaction force, the one or more lateral forces causing the sliding joint to slide; and
a computing device configured to control operation of the first series elastic actuator based on a torque of the at least one of the plurality of joints, the torque determined at least based on the spring element and rotation of the at least one of the plurality of joints.
2. The finger exoskeleton of claim 1 , wherein the first series elastic actuator further comprises Bowden cables.
3. The finger exoskeleton of claim 2 , wherein a sheath of the Bowden cable is fixed to the spring element.
4. The finger exoskeleton of claim 2 , wherein an inner cable of the Bowden cable is fixed to the spring element.
5. The finger exoskeleton of claim 1 , wherein at least one of the plurality of joints are manufactured with additive manufacturing techniques.
6. The finger exoskeleton of claim 1 , further comprising a second series elastic actuator independently operable from the first series elastic actuator.
7. The finger exoskeleton of claim 1 , wherein at least one of the plurality of joints allows for passive motion.
8. The finger exoskeleton of claim 1 , wherein the torque is determined by the equation:
τ joint =K spring (θ joint −θ actuator )
9. The finger exoskeleton of claim 1 , the first series elastic actuator further comprising a motor.
10. The finger exoskeleton of claim 1 , wherein the finger exoskeleton operates in a force-control mode of operation.
11. The finger exoskeleton of claim 1 , further comprising an attachment connecting the finger exoskeleton to a metacarpal bone of a thumb of a user and configured to maintain contact with the thumb while the thumb is in motion.
12. The finger exoskeleton of claim 1 , wherein at least one of the plurality of joints is configured to be rotated by a plurality of series elastic actuators.
13. A method comprising:
measuring a first rotation of a joint of a robotic finger exoskeleton;
detecting a second rotation of a motor coupled to a series elastic actuator;
translating one or more lateral forces applied to the joint of the robotic finger into a normal reaction force;
determining a torque of the joint of the robotic finger exoskeleton based at least on the first rotation and a spring element of the series elastic actuator; and
modifying an operation of the series elastic actuator based on the torque.
14. The method of claim 13 , further comprising providing an assistive force to a user of the robotic finger exoskeleton.
15. The method of claim 13 , wherein modifying the operation of the series elastic actuator comprises ceasing a rotation of the joint of the robotic finger exoskeleton contrary to a previous planned motion.
16. A hand exoskeleton comprising:
a plurality of finger exoskeletons, each finger exoskeleton comprising:
a plurality of joints;
a plurality of sensors configured to measure rotation of at least some of the plurality of joints of the finger exoskeleton; and
a series elastic actuator comprising a spring element, the series elastic actuator configured to rotate at least one of the plurality of joints;
a sliding joint configured to translate one or more lateral forces applied to the at least one of the plurality of joints into a normal reaction force, the one or more lateral forces causing the sliding joint to slide; and
a computing device configured to control operation of the series elastic actuator based on a torque of the at least one of the plurality of joints, the torque determined at least based on the spring element and a rotation of the at least one of the plurality of joints.
17. The hand exoskeleton of claim 16 , wherein the series elastic actuator further comprises Bowden cables.
18. The hand exoskeleton of claim 16 , wherein a sheath of the Bowden cables is fixed to the spring element.
19. The hand exoskeleton of claim 16 , wherein an inner cable of the Bowden cable is fixed to the spring element.