A liquid shim includes a bag (24) defining a closed inner volume and having sealed openings spaced inwardly from a periphery of the bag. The sealed openings are sealed from the closed inner volume and delimit holes extending through the bag. A liquid shim material (22) is flowable through the closed inner volume around the sealed openings and is curable to form a solid. The liquid shim material has a liquid shim material volume being less than the closed inner volume of the bag. A method of creating a liquid shim, and a method of shimming a gap between components, is also disclosed.

A liquid shim includes a bag (24) defining a closed inner volume and having sealed openings spaced inwardly from a periphery of the bag. The sealed openings are sealed from the closed inner volume and delimit holes extending through the bag. A liquid shim material (22) is flowable through the closed inner volume around the sealed openings and is curable to form a solid. The liquid shim material has a liquid shim material volume being less than the closed inner volume of the bag. A method of creating a liquid shim, and a method of shimming a gap between components, is also disclosed.

A gas turbine engine is provided. The gas turbine engine includes a turbomachine having a low speed spool and a high speed spool; a rotor assembly coupled to the low speed spool; an electric machine rotatable with the low speed spool for extracting power from the low speed spool, for adding power to the low speed spool, or both; and an inter-spool clutch positioned between the low speed spool and the high speed spool for selectively coupling the low speed spool to the high speed spool.

A gas turbine engine is provided. The gas turbine engine includes a turbomachine having a low speed spool and a high speed spool; a rotor assembly coupled to the low speed spool; an electric machine rotatable with the low speed spool for extracting power from the low speed spool, for adding power to the low speed spool, or both; and an inter-spool clutch positioned between the low speed spool and the high speed spool for selectively coupling the low speed spool to the high speed spool.

Aerogels comprising a hydrophobic polyimide moiety, including hydrophobic polyimide aerogels, as well as methods of manufacture and applications thereof, are generally described.

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Aerogels comprising a hydrophobic polyimide moiety, including hydrophobic polyimide aerogels, as well as methods of manufacture and applications thereof, are generally described.

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Methods and apparatuses for performing automated operations using a high-density robotic cell. An apparatus comprises a first plurality of robotic devices; a second plurality of robotic devices; and a control system. Each of the second plurality of robotic devices is coupled to a single function end effector. The control system controls the second plurality of robotic devices to concurrently perform tasks at a plurality of locations on an assembly, while the first plurality of robotic devices independently maintain a clamp-up at each of the plurality of locations.

A quick attach bracket includes a first portion and a second portion aligned substantially perpendicular with the first portion, a retaining ridge disposed across the first portion and extending in the direction of the second portion, and a hub disposed on the second portion and extending in the direction of the first portion. The retaining ridge is configured to receive a flange of a structure. The hub includes a sidewall that extends from the second portion in the direction of the first portion, a façade aligned with the second portion, and a rounded portion connecting the sidewall and the façade to assist with installation of the hub into a recess or through-hole of the structure. The quick attach bracket is installable by hand via hooking of the retaining ridge on the flange and insertion of the hub into the recess or through-hole.

A quick attach bracket includes a first portion and a second portion aligned substantially perpendicular with the first portion, a retaining ridge disposed across the first portion and extending in the direction of the second portion, and a hub disposed on the second portion and extending in the direction of the first portion. The retaining ridge is configured to receive a flange of a structure. The hub includes a sidewall that extends from the second portion in the direction of the first portion, a façade aligned with the second portion, and a rounded portion connecting the sidewall and the façade to assist with installation of the hub into a recess or through-hole of the structure. The quick attach bracket is installable by hand via hooking of the retaining ridge on the flange and insertion of the hub into the recess or through-hole.

The invention discloses a system for hole making for an aircraft skin by normal positioning and locking. The hole-making system includes a posture adjustment part, a normal positioning and locking part and a hole-making execution part. This system solves the problems that the device in the prior art has high complexity and cumbersome positioning and does not adapt to complex curved surfaces, thereby failing to satisfy the needs of efficient hole making in different space states. In the present invention, the expansion of an outer expansion sleeve in a bottom sleeve locks a normal direction for hole making, thereby ensuring the positioning accuracy of the normal direction. An axial position is locked by the mutual cooperation of an axial positioning groove of the bottom sleeve and an axial positioning rib of the outer expansion sleeve. A hole-making auxiliary cylinder contracts to counteract part of an axial force for hole making.