Abstract: A caterpillar track shoe including a shoe having a plurality of screw holes in the sole; a caterpillar track type driving mechanism fastened to the screw holes of the shoe and controlled to move the shoe on a piece of land through a toe-controlled switch in the shoe and a selector switch on the base frame of the driving mechanism, the driving mechanism including a DC motor, a battery power supply, a caterpillar track assembly, and a gear box coupled between the DC motor and the drive wheel of the caterpillar track assembly.

Abstract: An inflatable safety air curtain device for vehicles includes an air curtain device mounted in the car in front and above the driver or the passengers and an infrared detecting device. The air curtain device consists of an inflatable air curtain furled on a shaft within a housing or compressed and folded up within the housing. The infrared detecting device is mounted at a farthest front end of the car and may, upon detecting any car or object within a critical range of the car, actuate an electromagnetic valve on the air curtain device to cause compressed air within the cylinder to flow into the air curtain to inflate the same so that the air curtain swells instantly downwardly to form a protective curtain for the driver or the passenger.