Earth-Mars cycler concept by Maciej Rebisz

Earth-Mars cycler is a specialized orbital trajectory designed to shuttle spacecraft between Earth and Mars on a regular, repeating schedule. When the cycler flies past Earth, it is caught by one or several small taxi vehicles, delivering crew and cargo aboard the cycler: The cycler in Rebisz's concept is designed to generate 0.38G strong artificial gravity (equivalent to gravity on Mars) in the rotating habitat modules:

Source: humanmars.net