Assertion: arm | /r/CapableOf | support the projection head
Facets:
Source sentences:
text: This is conventionally accomplished by providing a rack gear on the post and a pinion gear attached to an arm which supports the projection head.
text: In order to produce and maintain a satisfactory image at the screen it is necessary that the arm supporting the projection head be firmly positioned relative to the base and free of movement in any direction other than perpendicular to the plane of the projector stage.