[MOC] Lego Technic Single Motor Tank V2.0

[TechnicBrickPower]

Hi Everyone. Here I present my second new and improved version of a tank that is driven by a single power functions motor. In this version the gearing mechanism has been optimized and far fewer gears are used to create the four different track direction combinations, namely both forward, both reverse, one forward & one reverse (turn left), and the opposite to turn right. Also the motor has been upgraded to an XL power functions motor instead of the large power functions motor. This gives an extra 0.5 watts of peak power. The tank can be controlled remotely using a single remote channel and driven forwards, backwards, and steered left and right. These functions are implemented by exploiting the direction of rotation of the motor to either drive the tank or select one the four track functions. This is done by a swinging liftarm with a gear that connects the motor output to one of two separate axles - one for driving the tank and one for selecting the track functions. The track functions are built using 2 orange rotary catches to switch a gearbox design that allows both tracks to be selected to drive forwards or backwards or to drive in either of the two opposite directions for steering. The track function selector uses a 90 degree stepper and a knobbed wheel to drive the rotary catches.

Enjoy.

 

[Horologist]

Great model, it fixed most of the flaws of the previous one. It also looks a lot cooler . I can't shake the feeling that there's a simpler way to do it with a differential, though... perhaps something like this would work? I don't have the parts to build it irl, but the concept seems to be there.

Edited May 10, 2021 by Horologist

[teetertater]

Super cool! Very nice execution of the concept and a great application of a binary counter irl 

[lmdesigner42]

Great proof of concept model! It definitely has a better and simpler drivetrain than version 1. Would it be possible to apply the same principle to a single motor RC car? i.e. the gearbox selects between 6 combinations of forward/reverse and left/right/straight.

[SUPER Max Black]

This mechanism, the explosion of the brain.

Or is it a very scary thing.

Edited May 13, 2021 by SUPER Max Black

[msk6003]

On 5/13/2021 at 10:09 AM, lmdesigner42 said:

Great proof of concept model! It definitely has a better and simpler drivetrain than version 1. Would it be possible to apply the same principle to a single motor RC car? i.e. the gearbox selects between 6 combinations of forward/reverse and left/right/straight.

Little harder to build but possable. I made twin motor wheeled excavator which has 6 function but work with only 2 L motor.