A kind of rail-mounted electric transportation vehicle in the factory. First of all, it is a track-type transportation vehicle that needs to be laid on the ground. The track is generally an I-shaped surface contacting the track; secondly, it is an electric drive vehicle, which is decelerated by the motor. Driven by the machine, it runs automatically. Once again, it is a flatbed truck with a flat table without a cover. In special cases, it can also be non-planar but without a cover. The car body has no steering wheel and only moves forward and backward (even when turning, it turns on the track).
