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Torsional Ratcheting Actuator

The Torsional Ratcheting Actuator (TRA)

The TRA uses a rotationally vibrating (oscillating) inner frame to ratchet its surrounding ring gear. Charging and discharging the inner interdigitated comb fingers causes this vibration.

Angle View

Visible in this image: the outer ring gear along with (front to back):a pointer that indicates the degrees of oscillation of the inner frame, the electrical interconnect that supplies power to the engine, and a clip that holds the ring in place.

Force Testing Mechanism

A spring scale after it has been distorted by the force produced by the TRA.

Force Testing Mechanism

This is a close-up view of the linear rack that delivers the TRA's force to the spring scale so that it can be measured.

Ratchet Pawl

In this image, one of the TRA's ratchet pawls is visible. The pawls convert the small oscillations of the inside frame into a continuous rotation of the surrounding gear.

Gear Constraint

This is a close-up of one of the clips that hold the outer ring gear in plane.

Electrical Interconnect

The arm, or beam, in the center of this image is an electrical interconnect that delivers electrical signals which power the TRA.

Electrical Interconnect

This is another view of the electric interconnect.

Angle Indicator

This pointer indicates the number of degrees of oscillation of the inner frame.

Anti-reverse Mechanism

This anti-reverse mechanism ensures that the ring gear can rotate in only one direction.

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