Axel is a rover currently under development through a joint collaboration between the Jet Propulsion Laboratory and the California Institute of Technology.

A primary goal of the Axel system design is minimal complexity and mass. It is fundamentally a two-wheeled rover with a symmetrical body and a trailing link. Axel uses only three actuators to control its wheels, trailing link, and tether.

Mounted from a host platform such as the Mars Science Laboratory, Axel is designed for steep terrain excursions and sampling on planetary surfaces. Specifically, Axel is ideally suited to travel into craters on the Moon or Mars.