This video shows how to build a model mass driver, also called a coilgun, controlled by an Arduino. Mass drivers could be used to launch payloads into space with electromagnets instead of chemical rockets. There are many variables you can change in your mass driver for a science or engineering project, like the power supply, coil geometry, or drive electronics. Written instructions, including a materials list, circuit diagram, and working example code are available on the Science Buddies website: https://www.sciencebuddies.org/science-fair-projects/project-ideas/Elec_p094/electricity-electronics/arduino-mass-driver