This video presents a revised version of an earlier Lego Technic Powered Up 3 speed automatic gearbox that I created. The previous gearbox used a differential for torque measurement and used a powered up large motor to convert the differential rotation into a torque measurement. However as many viewers have pointed out, it is possible to simply use the main motor speed measurement to infer the torque on that motor simply through the inverse linear relationship between the motor speed and it's load or torque. This saves the entire torque measurement portion of the gearbox resulting in a more compact and robust design. I also discuss the optimal gear switching points based on the gearing ratio R between the higher and lower gear. Thanks to philo (https://www.philohome.com/) for the torque vs speed graphs for the powered up motors.

 

 

Good work!

I'd be quite interested in seeing some screenshots of the code you used for this transmission!