ok ok I know that the cannon is a bit small. There was no blueprints so i had to use a digital art drawing.

Wookieeepedia:
The AV-7 Antivehicle Cannon, also known as the AV-7 Mobile Cannon, the Republic Artillery Gun, the heavy cannon, or the Clone Artillery Cannon, was a self-propelled artillery unit used by the Galactic Republic during the Clone Wars. The vehicle could be operated by one clone tank gunner in a seat on the side of the gun, and had a chamber for refilling plasma shells to the side of the lower chassis.

The vehicle would be moved with its built in repulsorlifts until it reached a suitable firing position and then entrench itself on the ground, using four metallic feet for support.

Its artillery shells created a fairly large blast radius, able to take out both vehicles and surrounding droids in a single shot.

Production information::
Manufacturer:
Taim & Bak
Model:
AV-7
Type:
Antivehicle Artillery Cannon
Cost:
14,000 credits (8,000 used)
Technical specifications::
Length:
15.38 meters[1]
Armament:
Artillery shells
Crew:
1 gunner[2]
Usage::
Role(s):
Self-propelled artillery
Affiliation:
Galactic Republic[2]