A sandwich structure includes a first skin, a second skin, a first hinge member, and a second hinge member. The first hinge member may be movably coupled to the first skin and a first skin joint. The second hinge member may be movably coupled to the second skin and second skin joint. The first hinge member and the second member may be movably coupled to one another and a member joint located between the first and second skin joint.

An assembly and a method of joining a first part with a second part at an attachment area that includes a localized area on the first part. The localized area is cleaned and activated by a plasma jet. An organosilicon composition is applied by plasma-enhanced chemical vapor deposition to the localized area. An adhesive is applied to the localized area and the second part is mechanically fastened to the first part in the localized area.

Example implementations of a synthetic turf system comprise a turf tray and a turf element. The turf tray is rigid and planar, and has a lattice structure extending within the lateral perimeter. The turf element includes a backing portion and a blade portion. The blade portion is defined by a plurality of blades of artificial grass affixed to the backing portion, the backing portion is placed secured engagement with the upper side by way of, for example, adhesive or screws. The turf trays may include perimeter and auxiliary adhesive tracks, and an array of screw retention bosses. The system may include a sprinkler assembly mountable in the turf trays for washing down the turf elements. The sprinkler assembly may include mounting flanges configurable to accommodate mounting of various sprinklers. The system may include height-adjustable pedestals or joists to support the turf trays at a distance above the local horizontal surface.