This isn’t a terribly complicated circuit but more so using basic laws to maximize resources available and knowing which ones to use.
We had a “dumpster dive” competition last semester and my team won the racing/speed portion with our racer “The Unicorn”. More info for the event and setup can be found on my friends YT channel here. The circuit is simply AA batteries soldered in series driving directly to a DC motor. We tried to make a branch of LEDs which were lighting before the race but sadly disconnected right before. The CD rainbow mohawk was for added aerodynamic speed. The body is an old scanner, the chassis a printer mount, DC motors came from another printer, and the wheels from pizza boxes that were brought to the event and then hot glued for traction.
boydo.tech 