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Video and pictures from the flame shooting RFID enabled trampoline at the Maker Faire! See Dale catch some air! - "The High-Lighter is a trampoline based flame effect. The installation involves a volunteer from the audience jumping on a unmodified trampoline. An ultrasonic sensor placed below the trampoline measures the changes in the height of the trampoline canvas as the user jumps up and down. A microcontroller notes the changes reported by the sensor and triggers a single solenoid valve to open and close. Based upon on the amount of force being applied to the trampoline the solenoid valve will behave differently. The harder someone jumps on a trampoline the longer the solenoid valve will stay open, illuminating a cylindrical metal tube with stenciled designs. LP-Gas will be released through the solenoid valve while it is open and ignited by a nearby pilot light covered in steel wool. A RFID reader is included used to prevent the trampoline from being used without proper authority present." - Link.