An unmanned aerial vehicle (1400, 1500, 1600, 1700) comprising: a frame (1404, 1504, 1604,1704) comprising: a first uni-body frame comprising a hub, four motor arms extending from the hub, four motor mounts (1411, 1511), each on a respective motor arm, and three support arms extending between each motor mount and a perimeter protective barrier (1414, 1514, 1614, 1714), the perimeter protective barrier forming a perimeter of the frame and comprising a vertical component, the vertical component extending substantially downward from the support arms, and a horizontal component that extends outward, with respect to the hub, from the vertical component; and a second, matching, uni-body frame stacked on and coupled to the first uni-body frame; four motors (1416,1516,1616) each mounted to an inner side of a respective motor mount (1411, 1511) of the first uni-body frame; four motors (1416, 1516, 1616) each mounted to an inner side of a respective motor mount of the second uni-body frame; and a plurality of propellers (1418, 1518, 1618, 1718), each propeller coupled to a motor of the motors (1416, 1516, 1616), wherein the vertical component extends approximately perpendicular to an axis of rotation of the propellers (1418, 1518, 1618, 1718), wherein the perimeter protective barrier (1414, 1514, 1614, 1714) of each uni-body frame extends around the perimeter of the propellers, wherein the motor arms and support arms of each uni-body frame are on an outer side of their respective motors so that each motor and corresponding propeller is within the frame, and wherein the perimeter protective barrier of the first uni-body frame and the perimeter protective barrier of the second uni-body frame are joined around their respective horizontal components such that the horizontal component of the perimeter protective barrier of the first uni-body frame and the horizontal component of the perimeter protective barrier of the second uni-body frame are in contact with one another along their complete circumference. a frame (1404, 1504, 1604,1704) comprising: a first uni-body frame comprising a hub, four motor arms extending from the hub, four motor mounts (1411, 1511), each on a respective motor arm, and three support arms extending between each motor mount and a perimeter protective barrier (1414, 1514, 1614, 1714), the perimeter protective barrier forming a perimeter of the frame and comprising a vertical component, the vertical component extending substantially downward from the support arms, and a horizontal component that extends outward, with respect to the hub, from the vertical component; and a second, matching, uni-body frame stacked on and coupled to the first uni-body frame; a first uni-body frame comprising a hub, four motor arms extending from the hub, four motor mounts (1411, 1511), each on a respective motor arm, and three support arms extending between each motor mount and a perimeter protective barrier (1414, 1514, 1614, 1714), the perimeter protective barrier forming a perimeter of the frame and comprising a vertical component, the vertical component extending substantially downward from the support arms, and a horizontal component that extends outward, with respect to the hub, from the vertical component; and a second, matching, uni-body frame stacked on and coupled to the first uni-body frame; four motors (1416,1516,1616) each mounted to an inner side of a respective motor mount (1411, 1511) of the first uni-body frame; four motors (1416, 1516, 1616) each mounted to an inner side of a respective motor mount of the second uni-body frame; and a plurality of propellers (1418, 1518, 1618, 1718), each propeller coupled to a motor of the motors (1416, 1516, 1616), wherein the vertical component extends approximately perpendicular to an axis of rotation of the propellers (1418, 1518, 1618, 1718), wherein the perimeter protective barrier (1414, 1514, 1614, 1714) of each uni-body frame extends around the perimeter of the propellers, wherein the motor arms and support arms of each uni-body frame are on an outer side of their respective motors so that each motor and corresponding propeller is within the frame, and wherein the perimeter protective barrier of the first uni-body frame and the perimeter protective barrier of the second uni-body frame are joined around their respective horizontal components such that the horizontal component of the perimeter protective barrier of the first uni-body frame and the horizontal component of the perimeter protective barrier of the second uni-body frame are in contact with one another along their complete circumference.