Grouser

Grousers are devices intended to increase the traction of continuous tracks, especially in loose material such as soil or snow.

This is done by increasing contact with the ground with protrusions, similar to conventional tire treads, and analogous to athletes' cleated shoes.

These include strakes, where material is removed from the surface of the wheel to achieve protrusion; cleats, with spikes instead of straight bars; and lugs with raised rubber on a tire tread.

While grousers are usually straight, they may have more complex shapes, including spikes[4] and involute curves, depending on the type of terrain and the performance requirements of the vehicle.

[5] Grousers are typically made of metal, such as forged steel, and are not designed for use on paved roads.

Grousers have been used in such exotic environments as the deep sea floor, and the surfaces of the Moon and Mars.

[6] Protrusions molded into rubber tractor tire treads are known as lugs, as are cleats for round wheels,[citation needed] which perform a similar function.

Unlike metal grousers, these rubber tire treads or crawler-track shoes/pads may be more suitable for driving on roads.