Belt conveyors play an important role in the transportation of dry bulk material in different industries. The inspection of its components, such as idlers, is a fundamental task to guarantee the conveyor belt proper functioning. Traditionally, operators perform inspections based on sound, vision, and smell. This work proposes a robotic device, composed by a mobile platform, a robotic arm and a set of sensors for idlers inspection. The proposed system removes the operator from risk areas, provides more accurate information and does not require any modification of the existing BC structures. Proof of concept tests were performed in real scenarios to confirm the system's capabilities under different operating conditions.