This video presents a lego technic two speed automatic gearbox using two motors and the Powered Up (PU) lego technic control system. Each motor uses a pivoting gear to either connect to it's gear to the left when rotating in the forward direction or to the gear to the right when reversing. Th...read more

Here I present my design for a compact and powerful Lego Technic 2 speed automatic gearbox.

The gearbox uses the Lego Technic Powered Up functions to detect speed and deduce torque from that to make gear switching decisions. The gearbox switches between a high gear of 1 to 4, to a low gea...read more

The Lego Technic set 42140 App-Controlled Transformation Vehicle introduces two new gears - a flat version of the 12 tooth bevel gear and a flat version of the 20 tooth bevel gear. These gears are designed to have less friction.

In this video I measure the difference in gearing efficiency...read more

Here I present a Pi Day special Lego Technic machine that produces a gearing ratio of Pi/8 using a 56mm wheel driving a 13x13 square wheel.

The correctness of the ratio is confirmed by matching it with output of a 2 differential gearing system that produces a ratio of 355/9...read more

This video describes a method for measuring the efficiency of a gearbox using the Lego Technic Powered Up hub. Gearbox efficiency is defined as the ratio of the output power to the input power and here I show how to measure each of these values to allow you to calculate the overall efficiency.read more

The lego technic Powered Up motors and functions have been used to create a lego technic 3 speed automatic gearbox. With the lego Powered Up functions you can accurately control motor speed and motor position, as well as being able to measure the angular position of a motor. These new possibiliti...read more

A lego technic 2 speed automatic gearbox is presented. The point of difference of this automatic 2 speed gearbox is a secondary booster motor is activated once the torque detector senses a large enough torque on the output of the automatic gearbox.

The second motor is turned on by a pole ...read more

This video applies lego technic gearbox, torque, and gearing ratio theory to design a prototype lego 2 speed automatic gearbox. First I describe the main components of an automatic gearbox, namely a gearing ratio selector and a torque detector. The ideal gear switch over torque point is described...read more

This video presents a lego technic 3 speed automatic gearbox design that failed to work as expected. This design is based on an earlier design of a 2 speed automatic gearbox with smooth transmission that worked very well.  That technic gearbox was extended by adding another speed to the oran...read more

This video presents my latest compact and smoothly switching 2 speed automatic gearbox made out of Lego Technic.  It is both smoothly switching and compact.

The MOC gearbox automatically switches down in gearing ratio when the load on the output is sufficiently high by using a new te...read more