My first ever project in university was a remote-controlled detection system. The remote sends the command and the IR sensor receives, either enabling or disabling the system. If enabled, the Arduino can detect any “intruders” and begin sounding an alarm as demonstrated in the video below. This was my first exposure to EE and it set me on a trajectory to the actual EE classes.
RC Ultrasonic Detection Alarm System Demonstration Video
Bryan Lew | Electrical Engineering Student 