A rocking sensor device includes a primary bracket (1), a rotating shaft (2), rollers (3), magnets (4) and a magnetic induction sensor (5). The primary bracket (1) is rockably connected to the rotating shaft (2). The rollers (3) and the magnets (4) are mounted on both ends of the primary bracket (1) and their positions are symmetrical about the rotating shaft (2). The magnetic induction sensor (5) is mounted on the perimeter of the primary bracket (1) at a position such that it can sense rocking of the magnet (4) on any end with the primary bracket (1). The rocking sensor device is wear and corrosion resistant, and can be self-cleaning.