A project log for 350KG RC TANK - PROGRAM : CHAROGNARD

Design and construction of a 350KG (700lbs) RC TANK, from scratch

rc-ordnanceRC ORDNANCE 11/14/2020 at 20:360 Comments


(continued from log "Gearbox Mk1")

Since I was going to face major problems with the Mk1 gearbox, I anticipated the construction of Mk2, featuring :

-Sprocket tensioners

-Full metal shifting forks

-Additional shaft, allowing to dismount the gearbox more easily.

It features 4 reversible gears.

There are no synchronizers, jus basic dog clutches. The dog clutches are motioned by 9kg RC servos, from an arduino.

It is a semi-automated gearbox : when pushing "shift up" or "shift down", the algorithm does all the necessary steps to change gear.

It is a semi-intelligent gearbox that detects when errors occure (e.g. blocked mechanism) and acts accordingly.

The first trial turned to be pretty succesful and quite promissing :

From CAD....
... to reality


New metal forks

Switch detecting dog clutch position


Arduino + radio module


The concept proves working pretty well (including at high speed) without load.
We'll have to test it again with the rest of the transmission, (double differential + steering system) ; under load once the chassis is done ; and under full load once the turret is complete...