A robotic vacuum cleaner may include a housing, a displaceable bumper, an emitter/detector pair, and at least one divider. The displaceable bumper may be moveably coupled to the housing and may be configured to be displaced along at least one axis. The emitter/detector pair may have an emitter and a detector, wherein the emitter is configured to emit light through at least a portion of the displaceable bumper. The at least one divider may be disposed between the emitter and the detector of the emitter/detector pair.