The output of the custom gearboxes were distributed among the 8 wheels using a chain system to create an 8WD system. All chains are automatically tensioned using a spring loaded idler system
An exploded view of one side of the drivetrain.
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8 Wheeled Robot Base

I designed a drivetrain for a robot using 8 wheels to handle harsh terrain

Lander Holsinger
FIRST FTC7244 Out of the Box Robotics Melbourne, FL