Gears and Geartrains




In Lego Robotics class our teacher Mr. Wright taught us about adding gears and creating gear chains on our robots. He told us that lego gears had multiples of eight for the amounts of teeth on them. This can help greatly becuse it is easier to create ratios stating the relationship of the number of spins of the gearswhen we create gear trains. If you put a sixteen-tooth onto the motor and connect it to an eight-tooth gear with an axel and wheels attached to it the wheels will turn twice for every one time the motor spins once. That example sped up the robot but if you switched the two gears around the wheels would turn once for everytime the motor spins twice. In these examples the ratios of the spins of the motor-gear to the wheel-gears where 1:2 in the faster gear chain and 2:1 on the slower gear train. When a robot moves slower it has more strength but if it moves faster it has less strength. Also, the size of the wheels that you use afects speed. A larger wheel will travel faster than a smaller wheel so you can use gears to alter this slightly or greatly. Make sure that you do not make your robot too fast or it will be so weak it will tear itself apart near the motors but if it's too slow it isn't so reliable either.