Servo - January 2016

SERVO 01.2016 25

Six or More Wheel Drive

Six-wheel drive systems are much like four-wheel drive systems, though they tend to be used in a layout that has a relatively long wheel base relative to the track width. This results in a system that has high scrub, good tracking, and high stability.

One common tweak to the basic six-wheel drive system is to have the middle wheels lowered slightly. This results in a robot that rocks under acceleration, but greatly improves turning by reducing the effective wheel base relative to the track width.

Machines using this configuration are typically using the six-wheel drive configuration primarily to either provide more consistent traction on inconsistent surfaces or to provide additional redundant contact points with the ground to improve the chances of both sides of the drive system staying functional after receiving damage.

Tracked Drive

Tracked drive systems continue the trend of increased scrub, tracking, Scrub is at its maximum, tracking is very good, and stability is at its maximum.

When considering the wheel base of a tracked system, it can be measured from the front most contact point to the rear most contact point when the system is operating normally.

Variants to the basic tracked system include the addition of a suspension system to deal with rough terrain and the use of a dropped roller similar to the 6+ wheel drive systems.

With many events having flat floors, tracks are fairly uncommon as many of the biggest benefits to a long contact patch don’t come into play on flat surfaces.

Shuffler Drive

Shuffle drive systems occupy an unusual space in the drive system’s realm. When they were first introduced to the robot combat world, they were considered a form of walking mechanism, and most events gave a 100% weight bonus for walkers. This was quickly and brutally exploited, and resulted in the redefinition of a walking mechanism in most events rules. Now, there is a classification for novel non-walking drive systems in the rules that covers shuffle drive systems.

For some events, this doesn’t result in any weight bonus. For other events, robots that have drive systems that fit within the novel non-wheeled classification will receive a 50% weight bonus. This weight bonus