Lego Technic 2 Speed Auto Car Ramp Challenge - Part 2
A lego technic 2 speed automatic gearbox is put to the test by incorporating it into a lego 2 speed automatic car. This lego 2 speed automatic gearbox implements a number of design principles aimed at improving the gearbox performance - namely of placing the torque detector on a separate path to the main gearing power path to reduce torque and power losses in the lego gearbox, and using gear disengagement to switch gears instead of gear engagement.
A simple derivation is presented of the physics involved in driving up a ramp in order to determine the amount of additional torque required at the motor output to be able to overcome the gravity and the corresponding potential energy.
The torque of the large lego power function motor is measured by measuring the output axle speed using a laser tachometer and relating that to the linear torque/speed relationship of the motor. These measurements are demonstrated for the car without any loading and with simple horizontal motion.
Finally the car is put to the test by attempting to drive up a 40 degree ramp.
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