Friction drives offer certain advantages over gears. In particular, they generally run more quietly and are easier to manufacture than geared units. The friction drives used in revolving stages call for a large driving radius in order to reduce friction force. In traditional friction drives, the two friction wheels (driving and driven) must be highly and precisely circular. This makes the manufacture of the driven wheel difficult and uneconomical. In this paper, a floating and self-actuating friction drive device was developed with the use of a swinging gearbox. In this device, the driving wheel is floatable, so the driven wheel is permitted to have certain deviation of roundness in the make and certain eccentricity in the installation. This avoids the difficulties in making and installing the driven wheel. This is a strong point in the applications of the revolving stage and other large-scale revolving devices. Meanwhile, this configuration can adaptively generate a normal torque on demand by using a swinging gearbox. This relieves the friction wheels of a continuous and high-stress load, thus prolonging their workability. Also, this paper described the working principles of this new friction drive device and presented a force analysis.