An example virtual reality (VR) system includes a VR headset, a plurality of monitoring stations, and an image processing device. Each of the monitoring stations includes an image sensor to capture images of the VR headset and an environment in which the VR headset is used. The image processing device is to process the images captured by the monitoring stations to detect an object in the environment, and to transmit, to the VR headset, information that includes notification of the object detected.