Abstract: A 3D printing system comprises a pressure system to provide a negative pressure and a hopper having a first opening to receive powder to be used for printing, wherein the powder is received in an open state of the first opening. The hopper has a second opening to guide air from outside the hopper to inside the hopper and has a third opening connected to the pressure system so as to provide for a negative pressure inside the hopper, the negative pressure to overcompensate for the air receive through the second opening such that a pressure being lower when compared to an ambient pressure of the hopper is generated inside the hopper.

Abstract: Disclosed herein is a leg exoskeleton configured to aid motion (e.g., walking) of a user in need thereof. In particular, the exoskeleton includes a belt configured to attach the exoskeleton to the waist of a user. The exoskeleton further includes a leg frame configured to attach to at least one leg of the user through a hip attachment mechanism on the belt. Finally, the exoskeleton includes an energy storage subsystem that is configured to store and release energy as the user walks, particularly aiding the user in the forward motion of the leg when walking. Methods of using the leg exoskeleton are also provided.

Abstract: Disclosed herein is a leg exoskeleton configured to aid motion (e.g., walking) of a user in need thereof. In particular, the exoskeleton includes a belt configured to attach the exoskeleton to the waist of a user. The exoskeleton further includes a leg frame configured to attach to at least one leg of the user through a hip attachment mechanism on the belt. Finally, the exoskeleton includes an energy storage subsystem that is configured to store and release energy as the user walks, particularly aiding the user in the forward motion of the leg when walking. Methods of using the leg exoskeleton are also provided.