I am curious to know what gave that idea? From the photos, any linkage or cyclinders are hidden. You must be telepathic or a real sharp observer!!
Actually, the center wheel is allowed to pull up into the chasis when on the ramp. That lowers our center of gravity a little and helps keep at leat 3 wheels planted when we might have to approach on an angle. We force the wheels down when not on the ramp to improve manuverability. Without that center wheel, turning is impossible!! The Mountainboard tires have a tad more traction than the conveyor belt rubber does! Also, 6 wheelers as well as tank tread bots will teeter when at the crest of the ramp unless you pull the center up. Making for some ample oppurtunity to get tipped off the ramp!!!
