摘要 |
A vessel which is self-righting and stable without the need for a weighted base is comprised of a planar base and sides whose cross section is an arc of an involute defined by a circle inside the cup. The most extended point on the involute is at or adjacent to the rim of the cup while the least extended point is the point where the side joins the planar base. In preferred embodiments, the vessel includes both a cup portion and a lid which retains liquids in the cup portion such that the overall center of gravity remains on the side of the reaction force vector at the point of contact between the cup and the surface on which it is placed, toward the center of the vessel. |