Powered Up 3 Speed Automatic Gearbox
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 possibilities have been used to create a three speed automatic gearbox. One motor is used to measure the torque at the output of the gearbox by detecting the rotation of an output differential; another motor is used to accurately set the position of an orange rotary catch controlling the switching between three forward gears, and finally one large powered up motor is used to drive the gearbox. The gearbox implements 3 forward speeds at gearing ratios of 1 to 1, 1 to 0.6 and 1 to 0.2 as well as one manual reverse gear. The Lego Powered Up app has been used to program the gearbox controller on an iphone. Thanks to @racingbrick (racingbrick.com) for providing a great guide to all of the available programming blocks.
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Lego Technic Powered Up 3 Speed Automatic gearbox 2
This video presents a revised version of an earlier Lego Technic Powered Up 3 speed automatic gearbox. 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 it turns out ...read more
Lego Technic 3 Speed Automatic Gearbox - FAIL!
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
Lego Technic 3 Speed Automatic Gearbox
Here a Lego Technic 3 speed automatic gearbox is presented. The gearbox automatically switches between one of 3 gear ratios, namely a ratio of 1, 1/3rd and 1/9th depending on the load on the output. It uses two 2 speed automatic transmissions in series to create the three speed automatic ge...read more
Lego Technic Powered Up 3 Speed Automatic Car
This video presents a new lego technic 3 speed automatic RC car. The gearbox uses the lego technic powered up hub and 3 motors to drive, steer and switch gears. The car's 3 speed automatic gearbox has 3 forward speeds with gear ratios 1:1, 3:5 and 1:5 and has been programmed us...read more
Lego Technic Servo Driven 3 Speed Automatic Gearbox
A lego technic 3 speed automatic gearbox is presented using a lego technic power function servo motor to drive the gear change mechanism. The servo motor is driven by a lego electric switch which in turn is driven by a torque detector using a differential at the output.
The technic automa...read more
Lego Technic Gearbox Theory Applied - how to apply theory to help design 2 speed automatic gearboxes
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
Lego Technic smoothly switching 2 speed automatic gearbox evolution with instructions
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
New Flat 12/20 Gear Friction
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
Lego Technic Pi Day Machine
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
Lego Technic Powered Up Tutorial 2 - Speed Control
This is my second Lego Technic Powered Up Tutorial that focusses on Lego Technic motor speed control using the Powered Up hub and Powered Up programming interface. The Lego Powered Up App is run on a Samsung Android tablet. I demonstrate how to set and control the power level applied to a motor.<...read more