A hypodermic syringe uncapping device includes a housing enclosing two opposed, pivotal arms adapted to grip a cap protecting a hypodermic syringe needle. Upon insertion through a hole in the housing, the capped needle is forced against a movable plunger whose lower end engages one of a number of pins extending from the surface of a rotatable cam located between the arms. Rotation of the cam thus induced allows the arms to pivot toward each other under the urging of an arm-connecting spring, causing the arms to grasp the cap and thereby allow subsequent withdrawal of the needle. When the needle is reinserted in the cap and the cap is again pushed against the plunger, the cam is rotated still further, forcing the arms apart and permitting the cap to be withdrawn from the device.
A collet end effector comprises two jaws pivotably mounted in a housing for movement between an open and a closed position. A collet sleeve surrounds the jaws and is slidably mounted in the housing for movement along the jaws toward and away from a gripping end of the jaws. Each of the jaws has a cam surface; the collet sleeve has collet bearings for riding along the cam surface. The cam surface has a ramp region configured such that as the collet sleeve moves toward the jaws gripping end while the collet bearings ride along the ramp region, the jaws move toward the jaws closed position. The cam surface also has a dwell region extending from the ramp region toward the jaw gripping end configured such that as the collet sleeve moves toward the jaw gripping end while the collet bearings ride along the dwell region, the jaws are maintained in the jaw closed position. After the jaws have clamped a gripping fixture, this "overtravel" region of the sleeve allows mating of in electrical connector on the sleeve with an interface.
