204 that is affixed to post 219 by weldmounts 202 the computer board 200 is supported above the chain support plate 203 by standoffs 201 that control the operation of the motor 211 that is mounted to the post 219 by means of the post mounting plate 208 and motor mounting plate 209 the traveling roller assembly 214 is connected to the spool 217 by a connecting cable 207 and swivel connector 206 that rotates around the shaft 218 the motor 211 drives shaft 218 by means of gear box 210 that is held in place by bearings 212 216 and the revolution sprocket wheel 215 as the spool 217 rotates the traveling roller assembly 214 is raised or lowered resulting in the raising or lowering of the flexible barrier 213 fig7 shows a second alternative embodiment the motor 305 is located at the top of the invention and is directly linked to a windlass knobbed spool 306 by means of gear box 304 that actively raises and lowers the flexible barrier 307 and allows the excess barrier to drop freely to the bottom of post 309 the motor 305 and gear box 304 are supported by the mounting flange 303 and affixed to post 309 by means of the motor assembly chassis plate 302 also attached to the post 309 is the circuit board 301.