Patent ID: 7214000

Claim:
An on-grade unobtrusive barrier for controlling access of vehicles by guiding below grade at least part of an unauthorized vehicle attempting to enter while providing safe on-grade passage for at least one adult pedestrian even when set to deny passage of said vehicles, comprising: at least one controller, wherein said controller automates operation of said barrier; a trench described by a length, width and depth and having end and side walls, said end walls described by said width and said depth; at least one unobtrusive plate affixed by at least one biased hinge to the top of a first said end wall, said hinge biased by at least one spring; at least one tab affixed to the top of a second said end wall that is opposite said first end wall; wherein said biased hinge holds the free end of said plate against the bottom of said tab thus assuring said plate does not rise above grade; slidable support for said free end of said plate, wherein said vehicle is permitted to pass by sliding said slidable support under said free end; at least one first actuator in operable communication with said controller and said slidable support, wherein the operation of said actuator is automated via operation of said controller, and wherein should said vehicle attempt to pass without authorization, said support is disabled and at least a portion of said vehicle slides into said trench; and means for lifting a vehicle from said trench, said means for lifting in operable communication with said controller.