Jehad Abdullah Alfaleh
King Abdulaziz Secondary School, Zulfi, Saudi Arabia
Children safety is extremely important. This engineered invention is designed to allow for monitoring of children and alarming the house when children go through the main doors of the house.
The main idea of this invention lies in the design of the locations of the sensors. Two pairs of infra red sensors are located on the sides of the doors at different heights (low and high).
It was assumed that the average height of a walking child is 100 cm. The low pair of sensors are aligned and mounted on opposite sides of inner door frame at a height of 10 cm from floor. The second pair of sensors is mounted at a height of 110 cm.
When a child (with height of 100 cm or less) goes through the door the first pair of sensors activates an alarm circuit through a relay. The relay contacts also activate a video camera and transmit a video stream to the house main TV screen.
When an adult person (with height of 110 cm or more) goes through the door, both the low-level sensors and the high-level sensors are activated. Therefore, both relays are activated. The circuit is wired so that when both relays are activated, no alarm is initiated.
The alarm circuit can be configured to have audible or visible alarms or both. The audio alarm can be changed from normal siren to a short pre-recorded voice message using an announciator.