Robotic lawnmower system

A robotic lawnmower system comprising:

• a robotic lawnmower comprising
• a chassis provided with a set of wheels and at least one propulsion motor for propelling the robotic lawnmower via the set of wheels, the chassis enclosing the propulsion motor and a controller configured to control the operation of the at least one propulsion motor;
• and
• an outer shell defining an exterior face of the robotic lawnmower, the outer shell at least partly enclosing the chassis at a distance from the chassis, wherein the robotic lawnmower system further comprises:
• a sensor module comprising a sensor and a sensor module housing enclosing the sensor, wherein the sensor module comprises a chassis connection interface for mechanically connecting the sensor module to a module connection interface on an outer face of the chassis, inside the outer shell, thereby enabling the sensor module to be carried by the robotic lawnmower, wherein
• the sensor is configured to transmit and/or receive electromagnetic radiation along a transmission path,
• the sensor module housing comprises an air outlet and a first air inlet, and
• the sensor module comprises a fan configured to move air along an air guide from said first air inlet to the air outlet,
• wherein one of the air outlet and said first air inlet defines a sensing aperture positioned along the transmission path.

A robotic lawnmower comprising:

• a chassis provided with a set of wheels and at least one propulsion motor for propelling the robotic lawnmower via the set of wheels, the chassis enclosing the propulsion motor and a controller configured to control the operation of the at least one propulsion motor;
• and
• an outer shell defining an exterior face of the robotic lawnmower, the outer shell comprising a skirt at least partly enclosing the chassis at a distance from the chassis, and
• a radar module positioned between the chassis and the skirt, wherein the skirt comprises a skirt aperture in register with the radar module, and
• a sensor module comprising a sensor and a sensor module housing enclosing the sensor, wherein the sensor module comprises a chassis connection interface for mechanically connecting the sensor module to a module connection interface on an outer face of the chassis, thereby enabling the sensor module to be carried by the robotic lawnmower, wherein, when the sensor module is connected to the chassis, the sensor module holds the sensor outside a vertical projection of the chassis, between the chassis and the skirt,
• wherein the module connection interface is located on a top face of the chassis, and the sensor module housing extends downwards to a position vertically lower than the module connection interface.