Using Feynman ratchet principle, it is possible to rectify the random motion into directed flow of particles in a nonequilibrium environment. In this work, an experimental setup for a dusty plasma metal straight ratchet is designed to create an asymmetric plasma environment along the ratchet channel, achieving controllable rectification of micron-sized dust particles. Monodispersed dust particles can form a directional flow in the ratchet channel, and the transport direction can be precisely controlled by adjusting the discharge power and the gas pressure. Research on the transport of dust particles with varying sizes proves that the rectification effect is universal. To reveal the rectification mechanism of dust particles, a fluid model of plasma is adopted to calculate the two-dimensional distribution of plasma parameters within the ratchet channel. Further research through Langevin simulation shows that dust particles experience ratchet potentials with different asymmetric orientations at different suspension heights within the ratchet channel, leading to different transport directions. The results of this work lays a theoretical and experimental foundation for further realizing the separation of bi-disperse particles in dusty plasma metal straight ratchets.