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 it is possible to simply use the main motor (Lego Techni powered up XL 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.
The Lego Powered Up app was used on an iphone to program the automatic gear switching points using a calculation based on an electric motor power curve and the gearing ratio between the current gear and the gear being switched down to.
The final lego technic 3 speed automatic gearbox using the Powered Up components is demonstrated at the end of the video.
More to explore
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
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 possibiliti...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
Spirograph Machine
Here I present a Lego Technic Spirograph machine programmed using Powered Up. The powered up controller is used to maintain the desired gearing ratio between the turn table and the inner gear to draw a spirograph that replicates the real original spirograph drawing toy.
...read moreLego 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 New 12/20 Gear High Speed Friction Test
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 follow up video I measure the high speed difference ...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
Gearing Ratio Calculator Tool Help
Measuring Gearbox Efficiency
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
Lego Technic Gearing Ratio Calculator Tool
Here I present my new Lego Technic Gearing Ratio Calculator tool. This tool allows you to upload your Lego Technic .ldr (Lego Draw) file and it will simulate the gearing system and visualize it as well as showing the gearing ratios relative to the input component.
The tool can be accessed...read more