John2019

I tried the dental floss but no luck, let me try the fishing line. Thanks for the tip.

Thanks for your response. I tried that that by tying a string to front and back axels to wind up around axles based on direction of the vehicle but the problems that I am facing are it's very hard to keep the string knot tight and if it's tight then string is breaking. Do you recommend any specific string?

Dear Friends: As a part of my middle school science Olympiad competition I built a battery buggy using Lego pieces like axels, gears, motor, battery etc but this project requires motorized vehicle to stop automatically after going for certain distance (9 to 12 meters) and I am unable to make any progress on stopping part. Does you guys have recommendations please? Thanks, John D