Lego Technic Automatic Reversing Gearbox MOC with Instructions
This lego technic gearbox has been designed to automatically reverse if there is a high load on the output. For example you may have a car that drives into a barrier and it will start driving backwards to avoid it. The MOC gearbox works by using a differential to react to the torque on the output. The differential drives a two state switch to select the reverse or forward direction in the gearbox. Forward and reverse are selected with a rotary catch component (introduced in the lego technic Bugatti Chiron Set) which selects the gearing ratios to create the forward or reverse directions.
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Lego Technic Two Degrees of Freedom 2 speed Automatic Gearbox
This lego technic 2 speed automatic gearbox implements it's second gear by using a two degrees of freedom configuration and blocking and unblocking the lower gearing ratio path by using a switch and rotary catch. The rotary catch is driven by a torque detector and once enough load is detected...read more
Lego Technic torque in practice - how to work with torque in automatic gearbox design
n this video I present a ten level Lego Technic torque creation gadget for testing lego power function motors and automatic gear switching mechanisms. The effect of torque on a large lego PF motor is tested against the theoretical power curve to compare the optimal gear switching point in practic...read more
Lego 2 speed automatic car. Part 1
This video explores the use of the lego technic "smoothly switching 2 speed automatic gearbox" inside of a test car to see how well it works to climb up a ramp.
The gearing ratio of the 2nd gear of the 2 speed automatic gearbox can be set using a manual 4 speed gearbox to choose...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
Lego Technic Powerful 2 Speed Auto Gearbox
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
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 2 Speed Automatic Gearbox with Booster Motor
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
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 pa...read more
Lego Technic 2 Speed Auto Gearbox - a new hope - with build instructions
This Lego technic 2 speed automatic gearbox design uses a worm gear for torque detection and gear switching combined. Previous Lego 2 speed automatic gearboxes have used a Lego differential for torque detection to drive an orange rotary catch to switch gears using a switch component.
The ...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