An autonomous vehicle roof top sensor module includes a shell attached to a roof of an autonomous vehicle. The shell includes a top panel, a bottom panel, and a front panel, which are connected together to define an interior, in which an internal sensor bracket is arranged to support a front middle portion of the top panel and provides a structure for mounting a sensor. The sensor is mounted on the sensor bracket and detects a characteristic of the autonomous vehicle or a characteristic of an environment surrounding the autonomous vehicle. The sensor bracket connects the front middle portion of the top panel to the bottom panel, and thus inhibits sagging of the top panel, and also provides a structure for mounting sensors in the shell.